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Re: [hreg] Solar Air Conditioners

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  • ChasMauch@aol.com
    I did a search under geo thermal air conditioners and come up with 880 listings. Most are for local shops all over the country etc but Enertran seems to be a
    Message 1 of 28 , Aug 31, 2001
      I did a search under "geo thermal air conditioners" and come up with 880
      listings. Most are for local shops all over the country etc but Enertran
      seems to be a big operator in the geo thermal field. They have a lot of
      general info on their web site at:

      http://www.attcanada.ca/~newave/geo.html      

      I'm sure there are a lot more. There are 43 pages of "air conditioning
      contractors" in the Houston yellow pages and I note that 3 or 4 specifically
      mention geo thermal in their ads. In fact one outfit's name is "Geo Thermal &
      A C Systems." Surely we could check with some of these guys to get more info
      on costs, problems, etc.

      Charlie
    • Polly Ledvina
      The website for the Geothermal Heat Pump Consortium is also a quite good: http://www.ghpc.org/home.htm Polly ... From: ChasMauch@aol.com To:
      Message 2 of 28 , Aug 31, 2001
        The website for the Geothermal Heat Pump Consortium is also a quite good:  http://www.ghpc.org/home.htm
         
        Polly
         
         
        ----- Original Message -----
        Sent: Friday, August 31, 2001 7:56 PM
        Subject: Re: [hreg] Solar Air Conditioners

        I did a search under "geo thermal air conditioners" and come up with 880
        listings. Most are for local shops all over the country etc but Enertran
        seems to be a big operator in the geo thermal field. They have a lot of
        general info on their web site at:

        http://www.attcanada.ca/~newave/geo.html      

        I'm sure there are a lot more. There are 43 pages of "air conditioning
        contractors" in the Houston yellow pages and I note that 3 or 4 specifically
        mention geo thermal in their ads. In fact one outfit's name is "Geo Thermal &
        A C Systems." Surely we could check with some of these guys to get more info
        on costs, problems, etc.

        Charlie


        Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
      • Robert Johnston
        I had exactly the same experience! I had been researching geothermal on a very casual basis. Then my A/C went out. I called some of the vendors I d learned
        Message 3 of 28 , Aug 31, 2001
          I had exactly the same experience! I had been researching geothermal on a
          very
          casual basis. Then my A/C went out. I called some of the vendors I'd
          learned
          about, and none of them could even start working on it for a couple weeks,
          and
          then the cost was very high, and they couldn't give me any reliable
          information
          about what my cost savings would be on electricity, or whether the mold
          issue in
          this area was real or not, etc.

          I agree with you on the marketing problem. Spec home builders aren't going
          to do
          this.

          However, I think that there really is a dearth of information from sources
          that
          people trust. Maybe if the vendors were the majors (Carrier, Goodman, etc.)
          then
          people would have more confidence in the product and would invest in it.

          If the payback is there, and if the data really support the efficiency
          improvements
          over time (e.g., not just when new, before pipes scum up and lose heat
          transfer,
          etc.) then it would be interesting for an innovative company to offer
          consumers
          a replacement unit with guaranteed cost savings, backed by a major bank.
          E.g.,
          suppose your replacement Carrier was going to set you back $1500 and this
          unit
          costs $5000. If the energy payback time is 4 years, then they could arrange
          for
          you to pay $1500 and get a $3500 loan that is paid back by the cost savings
          on
          your electricity bill, and if the savings don't happen, then the vendor eats
          it.

          I'm obviously not a businessman; this probably wouldn't fly. But somehow
          people
          have got to be made to believe in it if it really works. Of course, if it
          doesn't,
          then people need to know that, and the sooner the better.

          Robert

          -----Original Message-----
          From: B ridget Jensen [mailto:blj2@...]
          Sent: Friday, August 31, 2001 6:55 PM
          To: hreg@yahoogroups.com
          Subject: Re: [hreg] Solar Air Conditioners


          I was interested in the geothermal heat pump form of air conditioning.
          Where space is limited and holes must be drilled rather than simply
          trenching and burying the pipe over a large area, the cost does go up
          considerably I've been told. Nonetheless, I was still keen on putting in
          such a system. That is, until my existing system went totally out in the
          middle of summer and I wanted a/c asap. If most consumers are like me, they
          won't replace something that's still working. But then, when it does go
          out, there's no time to wait for installation of the geothermal heat pump,
          not to mention securing the loans that may be needed to pay for it.

          With that said, I think the target market would be new home builders. As
          builders of spec homes are usually trying to keep their costs low, at least
          for things that are invisible, such as air conditioning, I don't see any of
          the big homebuilders taking up this technology. Only someone who is
          involved in the design of their own home would probably employ an
          alternative a/c system.

          Bridget Jensen

          > From: "Robert Johnston" <rjohnsto@...>
          > Reply-To: hreg@yahoogroups.com
          > Date: Fri, 31 Aug 2001 18:14:18 -0500
          > To: <hreg@yahoogroups.com>
          > Subject: [hreg] Solar Air Conditioners
          >
          > Between the Nigerian Scams and the Environmental Spams, the good stuff is
          > hard to find here! However, there wasn't much comment on this note from
          > Billy Bell except Kevin pointing out the inefficiencies of thermoelectric
          > cooling (especially if tied to a solar cell!).
          >
          > However, it is an extremely interesting question and one I'd love to see
          > more discussion on. This is obviously one of the main barriers to this
          area
          > ever achieving the kind of renewable energy freedom that some other parts
          of
          > the country can do. The use of water as an evaporative coolant OK in
          > Arizona but not Houston--too humid already! In any case, even in a closed
          > system it wouldn't make a good medium for an efficient A/C.
          >
          > Anybody want to comment on what they think has the greatest potential in
          our
          > area?
          > Things that come to mind for me (besides ceiling fans, insulation, etc.)
          > are:
          >
          > 1. Dessicators. I know that natural gas fired units are now used for
          > commercial buildings in some locations. I don't know if any efficient
          solar
          > units have been designed. But if you could dry out the air, that would
          help
          > a lot. And then you might even be able to put a little cool water back in
          > as evaporative coolant as in Arizona.
          >
          > 2. Geothermal units. I'm puzzled why these haven't taken off, unless it
          is
          > their installation expense. Why are they so expensive? Are they not
          good?
          > A local A/C guy told me there are lots of problems with mold and odor in
          the
          > heat pump part of the installation. I don't know if that is true. He is
          > death on heat pumps **period** for that reason, and prefers straight
          A/C's.
          > But there is still something appealing to me of trying to cool compressed
          > gas with ground temperature rather than air temperature medium. I've seen
          > some of the numbers posted on the web (very high S.E.E.R.), but there is a
          > lot of hype by vendors. Since these aren't that popular, is it because
          they
          > don't work that well in practice, or is it just the cost of installation?
          > What is the payback period in this area, then? These are some questions
          I'd
          > like to see discussed.
          >
          > As far as ammonia goes, Billy--I know it is not nice stuff, but it used to
          > be used in refrigerators long ago, so with proper engineering I guess it
          was
          > managed OK. (Before my time, so I have no first hand experience). I also
          > know that TDC put some ammonia cooling systems on a couple of new warden's
          > homes at the prison farm south of Lake Jackson on the corner of
          > FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
          > optimally sloping roofs aimed towards the sun, and then on the rooftops
          were
          > solar collectors. They may have had solar hot water too--I don't
          > recall--but I remember reading in the newspaper when they built them about
          > their ammonia cooling systems. This would have been around 1981-85
          > timeframe. I also know that the collectors are now gone, but I don't know
          > why. It could just be that TDC didn't want to fuss with them--e.g., it
          may
          > have been environmentally "cool" (pun intended) to use solar on state
          > institutions at that time, but the maintenance expense for handling such
          an
          > unusual system that was different than all the other onsite A/C's might
          have
          > caused rethinking of the project down the road. Or, it may be that the
          > units just didn't hold up to use. I don't know, but I assume you could
          find
          > out more by asking around, or writing TDC.
          >
          > In any case, if any of you have some thoughts on the subject of solar or
          > just more efficient air conditioning/cooling, why don't we see if we can
          get
          > a discussion going on this subject and enlighten ourselves?
          >
          > Robert Johnston
          >
          > -----Original Message-----
          > From: William M. Bell, Jr. [mailto:wmb@...]
          > Sent: Wednesday, August 29, 2001 9:23 AM
          > To: hreg@yahoogroups.com
          > Subject: Re: [hreg] Digest Number 281
          >
          >
          >> Wow! What an email regarding the livestock industry and the whales. Who
          > are
          >> they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much for
          > me.
          >>
          >> Steve Stelzer
          >
          > I thought that livestock produced methane, which was a renewable? Just
          > Kidding ; ) Although I appreciate information of this sort, I am more
          > concerned that this discussion group stays on target.
          >
          > By the way, I have been doing a great deal of looking around in my spare
          > time (which is not much) at solar air conditioners. There a number of
          > alternatives out there. It sounds strange until you view solar as an
          energy
          > source (heat). Most solar air conditioners work by a process called
          > adsorption. An efficient, economical solar a/c system, that could be used
          in
          > residential cooling would be an important contribution to renewable
          energy.
          > Think of the amount of heat generated in this city by a/c and the amount
          of
          > electricity that is wasted producing this heat.
          >
          > The adsorption units that I have looked at use either ammonia
          (refrigerant)
          > and calcium chloride (absorber) (or some other chemical) or water and
          silica
          > gel. The water and silica gel seems most promising to me. Ammonia is too
          > dangerous to have inside my house and it makes it difficult to work out a
          > system in which I can keep it outside. Water, however, is safe and when it
          > evaporates, absorbs a great deal of heat.
          >
          > There is also a solid state alternative that I have not had much
          opportunity
          > to explore. They use solid state refrigerators in small outdoor coolers.
          > When you pass a 12V current through the diode, one side gets hot and the
          > other side gets cool. Perhaps, we could use the hot side to pre-heat our
          > water to the hot water heater and the cold side to chill water that could
          be
          > used to cool the house, if needed. The unit could be attached to solar
          > panels that produce the 12V current. The hotter it is outside, the harder
          > the unit works. I like that!
          >
          > Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
          > http://www.adsorptionchiller.com/
          >
          > Billy Bell
          > PO Box 926
          > Fulshear, Texas 77441-0926
          >
          > 713-439-1115 Telephone
          > 281-346-0994 Fax
          > wmb@...
          >
          >
          >
          >
          >
          > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
          >
          >
          >
          >
          >
          >
          >
          >
          > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
          >
          >





          Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
        • Robert Johnston
          I hadn t noticed the weblinks in my quick read before. Adsorption/absorption chillers are not new. We have one in the building where I work. They are
          Message 4 of 28 , Aug 31, 2001
            I hadn't noticed the weblinks in my quick read before.
            Adsorption/absorption chillers
            are not new. We have one in the building where I work. They are efficient
            on an
            industrial scale. I don't know what factors have kept them from scaling
            down to
            home use, but it would be interesting if they could.

            Actually, I suppose you could consider this a variant on the dessicant drier
            tech
            I mentioned, since silica after all is a dessicant.

            The Krum link is to Houston; anyone know these people? They appear just to
            be
            distributors, but maybe they might have some idea of the factors that limit
            downsizing.

            These units are industrial size, of course. Wonder if scaledown is even
            practical.
            These units are 6' x 9' x 9' and the input hot water flow is around 10 cubic
            feet/min.
            That is a little fast for most solar hot water heaters to produce! They
            seem better
            suited to cogeneration in industrial systems that generate heat.

            Anybody else have some thoughts on this?

            Robert

            -----Original Message-----
            From: William M. Bell, Jr. [mailto:wmb@...]
            Sent: Friday, August 31, 2001 6:50 PM
            To: hreg@yahoogroups.com
            Subject: Re: [hreg] Solar Air Conditioners


            Robert:

            Thanks for the interest. I am not opposed to ammonia. It simply makes life a
            little more complicated.

            I "designed" a system that used chilled water to cool and heated water to
            heat. The main problem was that it required a rather large, insulated
            holding tank. I proposed to use a concrete tank and bury it.

            I found a simpler design that used silica gel and water. It uses
            solar-heated water to squeeze the water out of the silica gel. If you looked
            at the web site that I listed, you can see a commercial application of such
            a system. It has much going for it: few moving parts; no corrosive
            chemicals; no excessive pressures or temperatures; and simple. The only
            problem is that I can't find any residential applications and information is
            scarce.

            Geothermal is cool, no pun intended. The main problem that I have
            encountered is that it is expensive to drill several wells and there is also
            a fear that you could contaminate your drinking water. That is geothermal
            that uses water wells. I have also heard of geothermal that circulated water
            through pipes located 10+ feet below ground. A friend of mine worked with a
            company that uses directional drilling to dig the lines for fiber optic
            cable and conduit. He thought that it would be an easy matter to use their
            machine to drill the circulating lines. My biggest obstacle, is that I have
            no idea how much line, etc that I would need. Lack of knowledge has stopped
            me once again. My thought was that I could put a coil in my air conditioner
            blower, before it got to the a/c coil, so that I could pre-cool my air. The
            idea was that if it worked well enough, the a/c would not need to kick in. I
            wanted to find a small circulating pump (again, I had no idea what size) and
            have it run by a solar panel. The hotter it is outside, the more it pumps. I
            have a friend in Lake Jackson who drilled several wells and used it to cool
            his house. It worked OK for a while, but then he had problems with his
            wells.

            Anyway, I think that this is an interesting area and we would all benefit
            from sharing our knowledge.

            ----- Original Message -----
            From: "Robert Johnston" <rjohnsto@...>
            To: <hreg@yahoogroups.com>
            Sent: Friday, August 31, 2001 6:14 PM
            Subject: [hreg] Solar Air Conditioners


            > Between the Nigerian Scams and the Environmental Spams, the good stuff is
            > hard to find here! However, there wasn't much comment on this note from
            > Billy Bell except Kevin pointing out the inefficiencies of thermoelectric
            > cooling (especially if tied to a solar cell!).
            >
            > However, it is an extremely interesting question and one I'd love to see
            > more discussion on. This is obviously one of the main barriers to this
            area
            > ever achieving the kind of renewable energy freedom that some other parts
            of
            > the country can do. The use of water as an evaporative coolant OK in
            > Arizona but not Houston--too humid already! In any case, even in a closed
            > system it wouldn't make a good medium for an efficient A/C.
            >
            > Anybody want to comment on what they think has the greatest potential in
            our
            > area?
            > Things that come to mind for me (besides ceiling fans, insulation, etc.)
            > are:
            >
            > 1. Dessicators. I know that natural gas fired units are now used for
            > commercial buildings in some locations. I don't know if any efficient
            solar
            > units have been designed. But if you could dry out the air, that would
            help
            > a lot. And then you might even be able to put a little cool water back in
            > as evaporative coolant as in Arizona.
            >
            > 2. Geothermal units. I'm puzzled why these haven't taken off, unless it
            is
            > their installation expense. Why are they so expensive? Are they not
            good?
            > A local A/C guy told me there are lots of problems with mold and odor in
            the
            > heat pump part of the installation. I don't know if that is true. He is
            > death on heat pumps **period** for that reason, and prefers straight
            A/C's.
            > But there is still something appealing to me of trying to cool compressed
            > gas with ground temperature rather than air temperature medium. I've seen
            > some of the numbers posted on the web (very high S.E.E.R.), but there is a
            > lot of hype by vendors. Since these aren't that popular, is it because
            they
            > don't work that well in practice, or is it just the cost of installation?
            > What is the payback period in this area, then? These are some questions
            I'd
            > like to see discussed.
            >
            > As far as ammonia goes, Billy--I know it is not nice stuff, but it used to
            > be used in refrigerators long ago, so with proper engineering I guess it
            was
            > managed OK. (Before my time, so I have no first hand experience). I also
            > know that TDC put some ammonia cooling systems on a couple of new warden's
            > homes at the prison farm south of Lake Jackson on the corner of
            > FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
            > optimally sloping roofs aimed towards the sun, and then on the rooftops
            were
            > solar collectors. They may have had solar hot water too--I don't
            > recall--but I remember reading in the newspaper when they built them about
            > their ammonia cooling systems. This would have been around 1981-85
            > timeframe. I also know that the collectors are now gone, but I don't know
            > why. It could just be that TDC didn't want to fuss with them--e.g., it
            may
            > have been environmentally "cool" (pun intended) to use solar on state
            > institutions at that time, but the maintenance expense for handling such
            an
            > unusual system that was different than all the other onsite A/C's might
            have
            > caused rethinking of the project down the road. Or, it may be that the
            > units just didn't hold up to use. I don't know, but I assume you could
            find
            > out more by asking around, or writing TDC.
            >
            > In any case, if any of you have some thoughts on the subject of solar or
            > just more efficient air conditioning/cooling, why don't we see if we can
            get
            > a discussion going on this subject and enlighten ourselves?
            >
            > Robert Johnston
            >
            > -----Original Message-----
            > From: William M. Bell, Jr. [mailto:wmb@...]
            > Sent: Wednesday, August 29, 2001 9:23 AM
            > To: hreg@yahoogroups.com
            > Subject: Re: [hreg] Digest Number 281
            >
            >
            > > Wow! What an email regarding the livestock industry and the whales. Who
            > are
            > > they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much for
            > me.
            > >
            > > Steve Stelzer
            >
            > I thought that livestock produced methane, which was a renewable? Just
            > Kidding ; ) Although I appreciate information of this sort, I am more
            > concerned that this discussion group stays on target.
            >
            > By the way, I have been doing a great deal of looking around in my spare
            > time (which is not much) at solar air conditioners. There a number of
            > alternatives out there. It sounds strange until you view solar as an
            energy
            > source (heat). Most solar air conditioners work by a process called
            > adsorption. An efficient, economical solar a/c system, that could be used
            in
            > residential cooling would be an important contribution to renewable
            energy.
            > Think of the amount of heat generated in this city by a/c and the amount
            of
            > electricity that is wasted producing this heat.
            >
            > The adsorption units that I have looked at use either ammonia
            (refrigerant)
            > and calcium chloride (absorber) (or some other chemical) or water and
            silica
            > gel. The water and silica gel seems most promising to me. Ammonia is too
            > dangerous to have inside my house and it makes it difficult to work out a
            > system in which I can keep it outside. Water, however, is safe and when it
            > evaporates, absorbs a great deal of heat.
            >
            > There is also a solid state alternative that I have not had much
            opportunity
            > to explore. They use solid state refrigerators in small outdoor coolers.
            > When you pass a 12V current through the diode, one side gets hot and the
            > other side gets cool. Perhaps, we could use the hot side to pre-heat our
            > water to the hot water heater and the cold side to chill water that could
            be
            > used to cool the house, if needed. The unit could be attached to solar
            > panels that produce the 12V current. The hotter it is outside, the harder
            > the unit works. I like that!
            >
            > Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
            > http://www.adsorptionchiller.com/
            >
            > Billy Bell
            > PO Box 926
            > Fulshear, Texas 77441-0926
            >
            > 713-439-1115 Telephone
            > 281-346-0994 Fax
            > wmb@...
            >
            >
            >
            >
            >
            > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
            >
            >
            >
            >
            >
            >
            >
            >
            > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
            >
            >





            Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
          • dans1
            Air Conditioning and other things. One of the major reasons that Biomass A?c has not taken off in the Houston area has to do with the water table around here.
            Message 5 of 28 , Aug 31, 2001
              Air Conditioning and other things.

              One of the major reasons that Biomass A?c has not taken off in the Houston
              area has to do with the water table around here. It would be very difficult
              for you to build one that didn't have problems with water seapage. This
              then brings up the problem with Mold and mildew. These two problems by them
              selves can be solved with proper designed de-humidifier systems in houses.
              Unfortunally the builders in the Houston area don't know thier head for a
              hold in the ground when it comes to building a house that uses the current
              style of air conditioners correctly. I recently moved out of a two story
              house that was a nightmare to heat and cool and the electrictiy bills were
              sky high. When the upstairs was cool the down stairs was hot and vice
              versa. Also the de-humidifier was way too small for the house which
              resulted in mold buildup inside the walls in areas like the bathrooms and
              closets. This mold resulted in severe health problems for my wife and her
              asama. Since moving to a new place, that was a well designed A/C system,
              all these problems have been eliminated.

              I see that the major problem with A/C in Houston is not the units them
              selves but how the houses are designed and built. I think that the Home
              builders need to go back to school and take a loot at historical houses in
              Texas and learn how to build a house that will last for over a hundred years
              and one that uses the natural enviroment to help heat and cool the house. I
              have been in some old 100 year plus houses in texas in the full heat of the
              summer that do not have A/C and they are cool inside. Thats becuse the
              builder knew how to build a house to make use of air flow and shading from
              large covered porches and cross ventalation from the placement of the
              windows.

              But when you have a home builder that is only concerened with making as much
              money as possible and cramming as many houses on a peice of land as
              possible, it would almost be impossible to build a enviromentaly passive
              house. Take my brother's house for an example. The lot is so small and the
              neighbors houses are so close that you can walk between them and streach out
              both arms to your side and you would touch both his house and his neighbors.
              6 feet people. I you wanted to put solar panels on the roof to generate any
              amount of electricity, it wouldn't do you any good since the two story
              houses around it would block the panels for half of the day. And as for as
              installing a Cistern to store rain water for water the grass, thats out
              cause the back yard is so small that there is not enough space to install a
              leach field.

              Until the builders change the way they build in Houston and texas, about the
              best you can do to use most of the available enviromentally friendly items
              out there, is to insulate, insulate, use double pane windows and to change
              to CF lights and energy efficent appliances.

              This is just my two cents worth.
              Dan

              ----- Original Message -----
              From: "Robert Johnston" <rjohnsto@...>
              To: <hreg@yahoogroups.com>
              Sent: Friday, August 31, 2001 6:14 PM
              Subject: [hreg] Solar Air Conditioners


              > Between the Nigerian Scams and the Environmental Spams, the good stuff is
              > hard to find here! However, there wasn't much comment on this note from
              > Billy Bell except Kevin pointing out the inefficiencies of thermoelectric
              > cooling (especially if tied to a solar cell!).
              >
              > However, it is an extremely interesting question and one I'd love to see
              > more discussion on. This is obviously one of the main barriers to this
              area
              > ever achieving the kind of renewable energy freedom that some other parts
              of
              > the country can do. The use of water as an evaporative coolant OK in
              > Arizona but not Houston--too humid already! In any case, even in a closed
              > system it wouldn't make a good medium for an efficient A/C.
              >
              > Anybody want to comment on what they think has the greatest potential in
              our
              > area?
              > Things that come to mind for me (besides ceiling fans, insulation, etc.)
              > are:
              >
              > 1. Dessicators. I know that natural gas fired units are now used for
              > commercial buildings in some locations. I don't know if any efficient
              solar
              > units have been designed. But if you could dry out the air, that would
              help
              > a lot. And then you might even be able to put a little cool water back in
              > as evaporative coolant as in Arizona.
              >
              > 2. Geothermal units. I'm puzzled why these haven't taken off, unless it
              is
              > their installation expense. Why are they so expensive? Are they not
              good?
              > A local A/C guy told me there are lots of problems with mold and odor in
              the
              > heat pump part of the installation. I don't know if that is true. He is
              > death on heat pumps **period** for that reason, and prefers straight
              A/C's.
              > But there is still something appealing to me of trying to cool compressed
              > gas with ground temperature rather than air temperature medium. I've seen
              > some of the numbers posted on the web (very high S.E.E.R.), but there is a
              > lot of hype by vendors. Since these aren't that popular, is it because
              they
              > don't work that well in practice, or is it just the cost of installation?
              > What is the payback period in this area, then? These are some questions
              I'd
              > like to see discussed.
              >
              > As far as ammonia goes, Billy--I know it is not nice stuff, but it used to
              > be used in refrigerators long ago, so with proper engineering I guess it
              was
              > managed OK. (Before my time, so I have no first hand experience). I also
              > know that TDC put some ammonia cooling systems on a couple of new warden's
              > homes at the prison farm south of Lake Jackson on the corner of
              > FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
              > optimally sloping roofs aimed towards the sun, and then on the rooftops
              were
              > solar collectors. They may have had solar hot water too--I don't
              > recall--but I remember reading in the newspaper when they built them about
              > their ammonia cooling systems. This would have been around 1981-85
              > timeframe. I also know that the collectors are now gone, but I don't know
              > why. It could just be that TDC didn't want to fuss with them--e.g., it
              may
              > have been environmentally "cool" (pun intended) to use solar on state
              > institutions at that time, but the maintenance expense for handling such
              an
              > unusual system that was different than all the other onsite A/C's might
              have
              > caused rethinking of the project down the road. Or, it may be that the
              > units just didn't hold up to use. I don't know, but I assume you could
              find
              > out more by asking around, or writing TDC.
              >
              > In any case, if any of you have some thoughts on the subject of solar or
              > just more efficient air conditioning/cooling, why don't we see if we can
              get
              > a discussion going on this subject and enlighten ourselves?
              >
              > Robert Johnston
              >
              > -----Original Message-----
              > From: William M. Bell, Jr. [mailto:wmb@...]
              > Sent: Wednesday, August 29, 2001 9:23 AM
              > To: hreg@yahoogroups.com
              > Subject: Re: [hreg] Digest Number 281
              >
              >
              > > Wow! What an email regarding the livestock industry and the whales. Who
              > are
              > > they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much for
              > me.
              > >
              > > Steve Stelzer
              >
              > I thought that livestock produced methane, which was a renewable? Just
              > Kidding ; ) Although I appreciate information of this sort, I am more
              > concerned that this discussion group stays on target.
              >
              > By the way, I have been doing a great deal of looking around in my spare
              > time (which is not much) at solar air conditioners. There a number of
              > alternatives out there. It sounds strange until you view solar as an
              energy
              > source (heat). Most solar air conditioners work by a process called
              > adsorption. An efficient, economical solar a/c system, that could be used
              in
              > residential cooling would be an important contribution to renewable
              energy.
              > Think of the amount of heat generated in this city by a/c and the amount
              of
              > electricity that is wasted producing this heat.
              >
              > The adsorption units that I have looked at use either ammonia
              (refrigerant)
              > and calcium chloride (absorber) (or some other chemical) or water and
              silica
              > gel. The water and silica gel seems most promising to me. Ammonia is too
              > dangerous to have inside my house and it makes it difficult to work out a
              > system in which I can keep it outside. Water, however, is safe and when it
              > evaporates, absorbs a great deal of heat.
              >
              > There is also a solid state alternative that I have not had much
              opportunity
              > to explore. They use solid state refrigerators in small outdoor coolers.
              > When you pass a 12V current through the diode, one side gets hot and the
              > other side gets cool. Perhaps, we could use the hot side to pre-heat our
              > water to the hot water heater and the cold side to chill water that could
              be
              > used to cool the house, if needed. The unit could be attached to solar
              > panels that produce the 12V current. The hotter it is outside, the harder
              > the unit works. I like that!
              >
              > Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
              > http://www.adsorptionchiller.com/
              >
              > Billy Bell
              > PO Box 926
              > Fulshear, Texas 77441-0926
              >
              > 713-439-1115 Telephone
              > 281-346-0994 Fax
              > wmb@...
              >
              >
              >
              >
              >
              > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
              >
              >
              >
              >
              >
              >
              >
              >
              > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
              >
              >
            • Kim & Garth Travis
              Hi, I am planning using cooled water to cool a 1000 sq. ft. building. My circulating pump is from a 15 diameter swimming pool. I installed my pipe under a
              Message 6 of 28 , Sep 1, 2001
                Hi,
                I am planning using cooled water to cool a 1000 sq. ft. building. My
                circulating pump is from a 15' diameter swimming pool. I installed my
                pipe under a raised garden bed that is filled with plants that like wet
                feet. In the testing we have done on the garden bed water, we seem to
                be washing the heat away. The plans call for the cooling pipe to be
                installed at the 8' level on the walls as well as in the floor.
                Kim

                William M. Bell, Jr. wrote:

                > Robert:
                >
                > Thanks for the interest. I am not opposed to ammonia. It simply makes life a
                > little more complicated.
                >
                > I "designed" a system that used chilled water to cool and heated water to
                > heat. The main problem was that it required a rather large, insulated
                > holding tank. I proposed to use a concrete tank and bury it.
                >
                > I found a simpler design that used silica gel and water. It uses
                > solar-heated water to squeeze the water out of the silica gel. If you looked
                > at the web site that I listed, you can see a commercial application of such
                > a system. It has much going for it: few moving parts; no corrosive
                > chemicals; no excessive pressures or temperatures; and simple. The only
                > problem is that I can't find any residential applications and information is
                > scarce.
                >
                > Geothermal is cool, no pun intended. The main problem that I have
                > encountered is that it is expensive to drill several wells and there is also
                > a fear that you could contaminate your drinking water. That is geothermal
                > that uses water wells. I have also heard of geothermal that circulated water
                > through pipes located 10+ feet below ground. A friend of mine worked with a
                > company that uses directional drilling to dig the lines for fiber optic
                > cable and conduit. He thought that it would be an easy matter to use their
                > machine to drill the circulating lines. My biggest obstacle, is that I have
                > no idea how much line, etc that I would need. Lack of knowledge has stopped
                > me once again. My thought was that I could put a coil in my air conditioner
                > blower, before it got to the a/c coil, so that I could pre-cool my air. The
                > idea was that if it worked well enough, the a/c would not need to kick in. I
                > wanted to find a small circulating pump (again, I had no idea what size) and
                > have it run by a solar panel. The hotter it is outside, the more it pumps. I
                > have a friend in Lake Jackson who drilled several wells and used it to cool
                > his house. It worked OK for a while, but then he had problems with his
                > wells.
                >
                > Anyway, I think that this is an interesting area and we would all benefit
                > from sharing our knowledge.
                >
                > ----- Original Message -----
                > From: "Robert Johnston" <rjohnsto@...>
                > To: <hreg@yahoogroups.com>
                > Sent: Friday, August 31, 2001 6:14 PM
                > Subject: [hreg] Solar Air Conditioners
                >
                >
                >
                >> Between the Nigerian Scams and the Environmental Spams, the good stuff is
                >> hard to find here! However, there wasn't much comment on this note from
                >> Billy Bell except Kevin pointing out the inefficiencies of thermoelectric
                >> cooling (especially if tied to a solar cell!).
                >>
                >> However, it is an extremely interesting question and one I'd love to see
                >> more discussion on. This is obviously one of the main barriers to this
                >
                > area
                >
                >> ever achieving the kind of renewable energy freedom that some other parts
                >
                > of
                >
                >> the country can do. The use of water as an evaporative coolant OK in
                >> Arizona but not Houston--too humid already! In any case, even in a closed
                >> system it wouldn't make a good medium for an efficient A/C.
                >>
                >> Anybody want to comment on what they think has the greatest potential in
                >
                > our
                >
                >> area?
                >> Things that come to mind for me (besides ceiling fans, insulation, etc.)
                >> are:
                >>
                >> 1. Dessicators. I know that natural gas fired units are now used for
                >> commercial buildings in some locations. I don't know if any efficient
                >
                > solar
                >
                >> units have been designed. But if you could dry out the air, that would
                >
                > help
                >
                >> a lot. And then you might even be able to put a little cool water back in
                >> as evaporative coolant as in Arizona.
                >>
                >> 2. Geothermal units. I'm puzzled why these haven't taken off, unless it
                >
                > is
                >
                >> their installation expense. Why are they so expensive? Are they not
                >
                > good?
                >
                >> A local A/C guy told me there are lots of problems with mold and odor in
                >
                > the
                >
                >> heat pump part of the installation. I don't know if that is true. He is
                >> death on heat pumps **period** for that reason, and prefers straight
                >
                > A/C's.
                >
                >> But there is still something appealing to me of trying to cool compressed
                >> gas with ground temperature rather than air temperature medium. I've seen
                >> some of the numbers posted on the web (very high S.E.E.R.), but there is a
                >> lot of hype by vendors. Since these aren't that popular, is it because
                >
                > they
                >
                >> don't work that well in practice, or is it just the cost of installation?
                >> What is the payback period in this area, then? These are some questions
                >
                > I'd
                >
                >> like to see discussed.
                >>
                >> As far as ammonia goes, Billy--I know it is not nice stuff, but it used to
                >> be used in refrigerators long ago, so with proper engineering I guess it
                >
                > was
                >
                >> managed OK. (Before my time, so I have no first hand experience). I also
                >> know that TDC put some ammonia cooling systems on a couple of new warden's
                >> homes at the prison farm south of Lake Jackson on the corner of
                >> FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                >> optimally sloping roofs aimed towards the sun, and then on the rooftops
                >
                > were
                >
                >> solar collectors. They may have had solar hot water too--I don't
                >> recall--but I remember reading in the newspaper when they built them about
                >> their ammonia cooling systems. This would have been around 1981-85
                >> timeframe. I also know that the collectors are now gone, but I don't know
                >> why. It could just be that TDC didn't want to fuss with them--e.g., it
                >
                > may
                >
                >> have been environmentally "cool" (pun intended) to use solar on state
                >> institutions at that time, but the maintenance expense for handling such
                >
                > an
                >
                >> unusual system that was different than all the other onsite A/C's might
                >
                > have
                >
                >> caused rethinking of the project down the road. Or, it may be that the
                >> units just didn't hold up to use. I don't know, but I assume you could
                >
                > find
                >
                >> out more by asking around, or writing TDC.
                >>
                >> In any case, if any of you have some thoughts on the subject of solar or
                >> just more efficient air conditioning/cooling, why don't we see if we can
                >
                > get
                >
                >> a discussion going on this subject and enlighten ourselves?
                >>
                >> Robert Johnston
                >>
                >> -----Original Message-----
                >> From: William M. Bell, Jr. [mailto:wmb@...]
                >> Sent: Wednesday, August 29, 2001 9:23 AM
                >> To: hreg@yahoogroups.com
                >> Subject: Re: [hreg] Digest Number 281
                >>
                >>
                >>
                >>> Wow! What an email regarding the livestock industry and the whales. Who
                >>
                >> are
                >>
                >>> they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much for
                >>
                >> me.
                >>
                >>> Steve Stelzer
                >>
                >> I thought that livestock produced methane, which was a renewable? Just
                >> Kidding ; ) Although I appreciate information of this sort, I am more
                >> concerned that this discussion group stays on target.
                >>
                >> By the way, I have been doing a great deal of looking around in my spare
                >> time (which is not much) at solar air conditioners. There a number of
                >> alternatives out there. It sounds strange until you view solar as an
                >
                > energy
                >
                >> source (heat). Most solar air conditioners work by a process called
                >> adsorption. An efficient, economical solar a/c system, that could be used
                >
                > in
                >
                >> residential cooling would be an important contribution to renewable
                >
                > energy.
                >
                >> Think of the amount of heat generated in this city by a/c and the amount
                >
                > of
                >
                >> electricity that is wasted producing this heat.
                >>
                >> The adsorption units that I have looked at use either ammonia
                >
                > (refrigerant)
                >
                >> and calcium chloride (absorber) (or some other chemical) or water and
                >
                > silica
                >
                >> gel. The water and silica gel seems most promising to me. Ammonia is too
                >> dangerous to have inside my house and it makes it difficult to work out a
                >> system in which I can keep it outside. Water, however, is safe and when it
                >> evaporates, absorbs a great deal of heat.
                >>
                >> There is also a solid state alternative that I have not had much
                >
                > opportunity
                >
                >> to explore. They use solid state refrigerators in small outdoor coolers.
                >> When you pass a 12V current through the diode, one side gets hot and the
                >> other side gets cool. Perhaps, we could use the hot side to pre-heat our
                >> water to the hot water heater and the cold side to chill water that could
                >
                > be
                >
                >> used to cool the house, if needed. The unit could be attached to solar
                >> panels that produce the 12V current. The hotter it is outside, the harder
                >> the unit works. I like that!
                >>
                >> Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                >> http://www.adsorptionchiller.com/
                >>
                >> Billy Bell
                >> PO Box 926
                >> Fulshear, Texas 77441-0926
                >>
                >> 713-439-1115 Telephone
                >> 281-346-0994 Fax
                >> wmb@...
                >>
                >>
                >>
                >>
                >>
                >> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                >>
                >>
                >>
                >>
                >>
                >>
                >>
                >>
                >> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                >>
                >>
                >
                >
                >
                >
                >
                >
                > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
              • Kevin L. Conlin
                Hi Robert, I believe that the biggest reason the solar/absorption chillers don t work well with solar is the reason you stated, the high flow rate, plus most
                Message 7 of 28 , Sep 1, 2001
                  Hi Robert, I believe that the biggest reason the solar/absorption chillers
                  don't work well with solar is the reason you stated, the high flow rate,
                  plus most solar thermal water heaters are not very efficient in the
                  temperature range these units need to run efficiently, typically around
                  boiling, 200 degrees plus. Although evacuated tube absorbers can reach this
                  range comfortably, they do not work well in Houston because of the
                  relatively low insolation levels. A large array is required. When I was in
                  the solar thermal business we did a feasibility to use solar AC at Moody
                  Gardens. The evacuated tube solar array was huge, as were the insulated
                  storage tanks, and the system was very expensive. Typically these
                  absorption units are designed to run on low grade steam left over from
                  manufacturing. I have seen large industrial systems like you mentioned that
                  have been running for decades with little maintenance and few problems, so
                  the technology is sound and proven, just not real compatible with most solar
                  thermal technologies.

                  To answer your earlier question, I believe the best prospect for splar AC is
                  the combination of efficient/traditional/passive solar home design, a
                  geothermal heat pump with a a ground loop. The reality is that if you build
                  a good passive solar/energy efficient home with a high SEER AC/heating unit,
                  your utility bills will be reasonable enough that a solar electric system is
                  no longer needed, but certainly a lot more practical. A few texas
                  architects, such as Mac Holder, Pliny Fisk, Laverne Williams and Bob Batho
                  have mastered the Texas climate with these combinations and their homes use
                  only a fraction of what your and my home use. As for builders getting it,
                  forget it! These architects are laying the technical groundwork for future
                  builders, not today's. As observed earlier, most are too stupid and greedy
                  to care about the people actually living in their homes. Sorry for the long
                  reply, but this topic sure has generated some interest. Best Regards,
                  kevin
                  ----- Original Message -----
                  From: "Robert Johnston" <rjohnsto@...>
                  To: <hreg@yahoogroups.com>
                  Sent: Friday, August 31, 2001 8:58 PM
                  Subject: RE: [hreg] Solar Air Conditioners


                  > I hadn't noticed the weblinks in my quick read before.
                  > Adsorption/absorption chillers
                  > are not new. We have one in the building where I work. They are
                  efficient
                  > on an
                  > industrial scale. I don't know what factors have kept them from scaling
                  > down to
                  > home use, but it would be interesting if they could.
                  >
                  > Actually, I suppose you could consider this a variant on the dessicant
                  drier
                  > tech
                  > I mentioned, since silica after all is a dessicant.
                  >
                  > The Krum link is to Houston; anyone know these people? They appear just
                  to
                  > be
                  > distributors, but maybe they might have some idea of the factors that
                  limit
                  > downsizing.
                  >
                  > These units are industrial size, of course. Wonder if scaledown is even
                  > practical.
                  > These units are 6' x 9' x 9' and the input hot water flow is around 10
                  cubic
                  > feet/min.
                  > That is a little fast for most solar hot water heaters to produce! They
                  > seem better
                  > suited to cogeneration in industrial systems that generate heat.
                  >
                  > Anybody else have some thoughts on this?
                  >
                  > Robert
                  >
                  > -----Original Message-----
                  > From: William M. Bell, Jr. [mailto:wmb@...]
                  > Sent: Friday, August 31, 2001 6:50 PM
                  > To: hreg@yahoogroups.com
                  > Subject: Re: [hreg] Solar Air Conditioners
                  >
                  >
                  > Robert:
                  >
                  > Thanks for the interest. I am not opposed to ammonia. It simply makes life
                  a
                  > little more complicated.
                  >
                  > I "designed" a system that used chilled water to cool and heated water to
                  > heat. The main problem was that it required a rather large, insulated
                  > holding tank. I proposed to use a concrete tank and bury it.
                  >
                  > I found a simpler design that used silica gel and water. It uses
                  > solar-heated water to squeeze the water out of the silica gel. If you
                  looked
                  > at the web site that I listed, you can see a commercial application of
                  such
                  > a system. It has much going for it: few moving parts; no corrosive
                  > chemicals; no excessive pressures or temperatures; and simple. The only
                  > problem is that I can't find any residential applications and information
                  is
                  > scarce.
                  >
                  > Geothermal is cool, no pun intended. The main problem that I have
                  > encountered is that it is expensive to drill several wells and there is
                  also
                  > a fear that you could contaminate your drinking water. That is geothermal
                  > that uses water wells. I have also heard of geothermal that circulated
                  water
                  > through pipes located 10+ feet below ground. A friend of mine worked with
                  a
                  > company that uses directional drilling to dig the lines for fiber optic
                  > cable and conduit. He thought that it would be an easy matter to use their
                  > machine to drill the circulating lines. My biggest obstacle, is that I
                  have
                  > no idea how much line, etc that I would need. Lack of knowledge has
                  stopped
                  > me once again. My thought was that I could put a coil in my air
                  conditioner
                  > blower, before it got to the a/c coil, so that I could pre-cool my air.
                  The
                  > idea was that if it worked well enough, the a/c would not need to kick in.
                  I
                  > wanted to find a small circulating pump (again, I had no idea what size)
                  and
                  > have it run by a solar panel. The hotter it is outside, the more it pumps.
                  I
                  > have a friend in Lake Jackson who drilled several wells and used it to
                  cool
                  > his house. It worked OK for a while, but then he had problems with his
                  > wells.
                  >
                  > Anyway, I think that this is an interesting area and we would all benefit
                  > from sharing our knowledge.
                  >
                  > ----- Original Message -----
                  > From: "Robert Johnston" <rjohnsto@...>
                  > To: <hreg@yahoogroups.com>
                  > Sent: Friday, August 31, 2001 6:14 PM
                  > Subject: [hreg] Solar Air Conditioners
                  >
                  >
                  > > Between the Nigerian Scams and the Environmental Spams, the good stuff
                  is
                  > > hard to find here! However, there wasn't much comment on this note from
                  > > Billy Bell except Kevin pointing out the inefficiencies of
                  thermoelectric
                  > > cooling (especially if tied to a solar cell!).
                  > >
                  > > However, it is an extremely interesting question and one I'd love to see
                  > > more discussion on. This is obviously one of the main barriers to this
                  > area
                  > > ever achieving the kind of renewable energy freedom that some other
                  parts
                  > of
                  > > the country can do. The use of water as an evaporative coolant OK in
                  > > Arizona but not Houston--too humid already! In any case, even in a
                  closed
                  > > system it wouldn't make a good medium for an efficient A/C.
                  > >
                  > > Anybody want to comment on what they think has the greatest potential in
                  > our
                  > > area?
                  > > Things that come to mind for me (besides ceiling fans, insulation, etc.)
                  > > are:
                  > >
                  > > 1. Dessicators. I know that natural gas fired units are now used for
                  > > commercial buildings in some locations. I don't know if any efficient
                  > solar
                  > > units have been designed. But if you could dry out the air, that would
                  > help
                  > > a lot. And then you might even be able to put a little cool water back
                  in
                  > > as evaporative coolant as in Arizona.
                  > >
                  > > 2. Geothermal units. I'm puzzled why these haven't taken off, unless
                  it
                  > is
                  > > their installation expense. Why are they so expensive? Are they not
                  > good?
                  > > A local A/C guy told me there are lots of problems with mold and odor in
                  > the
                  > > heat pump part of the installation. I don't know if that is true. He
                  is
                  > > death on heat pumps **period** for that reason, and prefers straight
                  > A/C's.
                  > > But there is still something appealing to me of trying to cool
                  compressed
                  > > gas with ground temperature rather than air temperature medium. I've
                  seen
                  > > some of the numbers posted on the web (very high S.E.E.R.), but there is
                  a
                  > > lot of hype by vendors. Since these aren't that popular, is it because
                  > they
                  > > don't work that well in practice, or is it just the cost of
                  installation?
                  > > What is the payback period in this area, then? These are some questions
                  > I'd
                  > > like to see discussed.
                  > >
                  > > As far as ammonia goes, Billy--I know it is not nice stuff, but it used
                  to
                  > > be used in refrigerators long ago, so with proper engineering I guess it
                  > was
                  > > managed OK. (Before my time, so I have no first hand experience). I
                  also
                  > > know that TDC put some ammonia cooling systems on a couple of new
                  warden's
                  > > homes at the prison farm south of Lake Jackson on the corner of
                  > > FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                  > > optimally sloping roofs aimed towards the sun, and then on the rooftops
                  > were
                  > > solar collectors. They may have had solar hot water too--I don't
                  > > recall--but I remember reading in the newspaper when they built them
                  about
                  > > their ammonia cooling systems. This would have been around 1981-85
                  > > timeframe. I also know that the collectors are now gone, but I don't
                  know
                  > > why. It could just be that TDC didn't want to fuss with them--e.g., it
                  > may
                  > > have been environmentally "cool" (pun intended) to use solar on state
                  > > institutions at that time, but the maintenance expense for handling such
                  > an
                  > > unusual system that was different than all the other onsite A/C's might
                  > have
                  > > caused rethinking of the project down the road. Or, it may be that the
                  > > units just didn't hold up to use. I don't know, but I assume you could
                  > find
                  > > out more by asking around, or writing TDC.
                  > >
                  > > In any case, if any of you have some thoughts on the subject of solar or
                  > > just more efficient air conditioning/cooling, why don't we see if we can
                  > get
                  > > a discussion going on this subject and enlighten ourselves?
                  > >
                  > > Robert Johnston
                  > >
                  > > -----Original Message-----
                  > > From: William M. Bell, Jr. [mailto:wmb@...]
                  > > Sent: Wednesday, August 29, 2001 9:23 AM
                  > > To: hreg@yahoogroups.com
                  > > Subject: Re: [hreg] Digest Number 281
                  > >
                  > >
                  > > > Wow! What an email regarding the livestock industry and the whales.
                  Who
                  > > are
                  > > > they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much
                  for
                  > > me.
                  > > >
                  > > > Steve Stelzer
                  > >
                  > > I thought that livestock produced methane, which was a renewable? Just
                  > > Kidding ; ) Although I appreciate information of this sort, I am more
                  > > concerned that this discussion group stays on target.
                  > >
                  > > By the way, I have been doing a great deal of looking around in my spare
                  > > time (which is not much) at solar air conditioners. There a number of
                  > > alternatives out there. It sounds strange until you view solar as an
                  > energy
                  > > source (heat). Most solar air conditioners work by a process called
                  > > adsorption. An efficient, economical solar a/c system, that could be
                  used
                  > in
                  > > residential cooling would be an important contribution to renewable
                  > energy.
                  > > Think of the amount of heat generated in this city by a/c and the amount
                  > of
                  > > electricity that is wasted producing this heat.
                  > >
                  > > The adsorption units that I have looked at use either ammonia
                  > (refrigerant)
                  > > and calcium chloride (absorber) (or some other chemical) or water and
                  > silica
                  > > gel. The water and silica gel seems most promising to me. Ammonia is too
                  > > dangerous to have inside my house and it makes it difficult to work out
                  a
                  > > system in which I can keep it outside. Water, however, is safe and when
                  it
                  > > evaporates, absorbs a great deal of heat.
                  > >
                  > > There is also a solid state alternative that I have not had much
                  > opportunity
                  > > to explore. They use solid state refrigerators in small outdoor coolers.
                  > > When you pass a 12V current through the diode, one side gets hot and the
                  > > other side gets cool. Perhaps, we could use the hot side to pre-heat our
                  > > water to the hot water heater and the cold side to chill water that
                  could
                  > be
                  > > used to cool the house, if needed. The unit could be attached to solar
                  > > panels that produce the 12V current. The hotter it is outside, the
                  harder
                  > > the unit works. I like that!
                  > >
                  > > Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                  > > http://www.adsorptionchiller.com/
                  > >
                  > > Billy Bell
                  > > PO Box 926
                  > > Fulshear, Texas 77441-0926
                  > >
                  > > 713-439-1115 Telephone
                  > > 281-346-0994 Fax
                  > > wmb@...
                  > >
                  > >
                  > >
                  > >
                  > >
                  > > Your use of Yahoo! Groups is subject to
                  http://docs.yahoo.com/info/terms/
                  > >
                  > >
                  > >
                  > >
                  > >
                  > >
                  > >
                  > >
                  > > Your use of Yahoo! Groups is subject to
                  http://docs.yahoo.com/info/terms/
                  > >
                  > >
                  >
                  >
                  >
                  >
                  >
                  > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  >
                  >
                  >
                • Mike Ewert
                  I think the reason absorption hasn t scaled down well is maintenance. Also, solar absorption works, but you need concentrating collectors which cost more.
                  Message 8 of 28 , Sep 1, 2001
                    I think the reason absorption hasn't scaled down well is maintenance. Also,
                    solar absorption works, but you need concentrating collectors which cost
                    more. Good flat plate collectors can do it, but it is marginal. Given a
                    little more engineering development and mass production, I have no doubt
                    they could compete. But, there is the bootstrap problem of getting to that
                    point.

                    -----Original Message-----
                    From: Robert Johnston [mailto:rjohnsto@...]
                    Sent: Friday, August 31, 2001 8:58 PM
                    To: hreg@yahoogroups.com
                    Subject: RE: [hreg] Solar Air Conditioners


                    I hadn't noticed the weblinks in my quick read before.
                    Adsorption/absorption chillers
                    are not new. We have one in the building where I work. They are efficient
                    on an
                    industrial scale. I don't know what factors have kept them from scaling
                    down to
                    home use, but it would be interesting if they could.

                    Actually, I suppose you could consider this a variant on the dessicant drier
                    tech
                    I mentioned, since silica after all is a dessicant.

                    The Krum link is to Houston; anyone know these people? They appear just to
                    be
                    distributors, but maybe they might have some idea of the factors that limit
                    downsizing.

                    These units are industrial size, of course. Wonder if scaledown is even
                    practical.
                    These units are 6' x 9' x 9' and the input hot water flow is around 10 cubic
                    feet/min.
                    That is a little fast for most solar hot water heaters to produce! They
                    seem better
                    suited to cogeneration in industrial systems that generate heat.

                    Anybody else have some thoughts on this?

                    Robert

                    -----Original Message-----
                    From: William M. Bell, Jr. [mailto:wmb@...]
                    Sent: Friday, August 31, 2001 6:50 PM
                    To: hreg@yahoogroups.com
                    Subject: Re: [hreg] Solar Air Conditioners


                    Robert:

                    Thanks for the interest. I am not opposed to ammonia. It simply makes life a
                    little more complicated.

                    I "designed" a system that used chilled water to cool and heated water to
                    heat. The main problem was that it required a rather large, insulated
                    holding tank. I proposed to use a concrete tank and bury it.

                    I found a simpler design that used silica gel and water. It uses
                    solar-heated water to squeeze the water out of the silica gel. If you looked
                    at the web site that I listed, you can see a commercial application of such
                    a system. It has much going for it: few moving parts; no corrosive
                    chemicals; no excessive pressures or temperatures; and simple. The only
                    problem is that I can't find any residential applications and information is
                    scarce.

                    Geothermal is cool, no pun intended. The main problem that I have
                    encountered is that it is expensive to drill several wells and there is also
                    a fear that you could contaminate your drinking water. That is geothermal
                    that uses water wells. I have also heard of geothermal that circulated water
                    through pipes located 10+ feet below ground. A friend of mine worked with a
                    company that uses directional drilling to dig the lines for fiber optic
                    cable and conduit. He thought that it would be an easy matter to use their
                    machine to drill the circulating lines. My biggest obstacle, is that I have
                    no idea how much line, etc that I would need. Lack of knowledge has stopped
                    me once again. My thought was that I could put a coil in my air conditioner
                    blower, before it got to the a/c coil, so that I could pre-cool my air. The
                    idea was that if it worked well enough, the a/c would not need to kick in. I
                    wanted to find a small circulating pump (again, I had no idea what size) and
                    have it run by a solar panel. The hotter it is outside, the more it pumps. I
                    have a friend in Lake Jackson who drilled several wells and used it to cool
                    his house. It worked OK for a while, but then he had problems with his
                    wells.

                    Anyway, I think that this is an interesting area and we would all benefit
                    from sharing our knowledge.

                    ----- Original Message -----
                    From: "Robert Johnston" <rjohnsto@...>
                    To: <hreg@yahoogroups.com>
                    Sent: Friday, August 31, 2001 6:14 PM
                    Subject: [hreg] Solar Air Conditioners


                    > Between the Nigerian Scams and the Environmental Spams, the good stuff is
                    > hard to find here! However, there wasn't much comment on this note from
                    > Billy Bell except Kevin pointing out the inefficiencies of thermoelectric
                    > cooling (especially if tied to a solar cell!).
                    >
                    > However, it is an extremely interesting question and one I'd love to see
                    > more discussion on. This is obviously one of the main barriers to this
                    area
                    > ever achieving the kind of renewable energy freedom that some other parts
                    of
                    > the country can do. The use of water as an evaporative coolant OK in
                    > Arizona but not Houston--too humid already! In any case, even in a closed
                    > system it wouldn't make a good medium for an efficient A/C.
                    >
                    > Anybody want to comment on what they think has the greatest potential in
                    our
                    > area?
                    > Things that come to mind for me (besides ceiling fans, insulation, etc.)
                    > are:
                    >
                    > 1. Dessicators. I know that natural gas fired units are now used for
                    > commercial buildings in some locations. I don't know if any efficient
                    solar
                    > units have been designed. But if you could dry out the air, that would
                    help
                    > a lot. And then you might even be able to put a little cool water back in
                    > as evaporative coolant as in Arizona.
                    >
                    > 2. Geothermal units. I'm puzzled why these haven't taken off, unless it
                    is
                    > their installation expense. Why are they so expensive? Are they not
                    good?
                    > A local A/C guy told me there are lots of problems with mold and odor in
                    the
                    > heat pump part of the installation. I don't know if that is true. He is
                    > death on heat pumps **period** for that reason, and prefers straight
                    A/C's.
                    > But there is still something appealing to me of trying to cool compressed
                    > gas with ground temperature rather than air temperature medium. I've seen
                    > some of the numbers posted on the web (very high S.E.E.R.), but there is a
                    > lot of hype by vendors. Since these aren't that popular, is it because
                    they
                    > don't work that well in practice, or is it just the cost of installation?
                    > What is the payback period in this area, then? These are some questions
                    I'd
                    > like to see discussed.
                    >
                    > As far as ammonia goes, Billy--I know it is not nice stuff, but it used to
                    > be used in refrigerators long ago, so with proper engineering I guess it
                    was
                    > managed OK. (Before my time, so I have no first hand experience). I also
                    > know that TDC put some ammonia cooling systems on a couple of new warden's
                    > homes at the prison farm south of Lake Jackson on the corner of
                    > FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                    > optimally sloping roofs aimed towards the sun, and then on the rooftops
                    were
                    > solar collectors. They may have had solar hot water too--I don't
                    > recall--but I remember reading in the newspaper when they built them about
                    > their ammonia cooling systems. This would have been around 1981-85
                    > timeframe. I also know that the collectors are now gone, but I don't know
                    > why. It could just be that TDC didn't want to fuss with them--e.g., it
                    may
                    > have been environmentally "cool" (pun intended) to use solar on state
                    > institutions at that time, but the maintenance expense for handling such
                    an
                    > unusual system that was different than all the other onsite A/C's might
                    have
                    > caused rethinking of the project down the road. Or, it may be that the
                    > units just didn't hold up to use. I don't know, but I assume you could
                    find
                    > out more by asking around, or writing TDC.
                    >
                    > In any case, if any of you have some thoughts on the subject of solar or
                    > just more efficient air conditioning/cooling, why don't we see if we can
                    get
                    > a discussion going on this subject and enlighten ourselves?
                    >
                    > Robert Johnston
                    >
                    > -----Original Message-----
                    > From: William M. Bell, Jr. [mailto:wmb@...]
                    > Sent: Wednesday, August 29, 2001 9:23 AM
                    > To: hreg@yahoogroups.com
                    > Subject: Re: [hreg] Digest Number 281
                    >
                    >
                    > > Wow! What an email regarding the livestock industry and the whales. Who
                    > are
                    > > they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much for
                    > me.
                    > >
                    > > Steve Stelzer
                    >
                    > I thought that livestock produced methane, which was a renewable? Just
                    > Kidding ; ) Although I appreciate information of this sort, I am more
                    > concerned that this discussion group stays on target.
                    >
                    > By the way, I have been doing a great deal of looking around in my spare
                    > time (which is not much) at solar air conditioners. There a number of
                    > alternatives out there. It sounds strange until you view solar as an
                    energy
                    > source (heat). Most solar air conditioners work by a process called
                    > adsorption. An efficient, economical solar a/c system, that could be used
                    in
                    > residential cooling would be an important contribution to renewable
                    energy.
                    > Think of the amount of heat generated in this city by a/c and the amount
                    of
                    > electricity that is wasted producing this heat.
                    >
                    > The adsorption units that I have looked at use either ammonia
                    (refrigerant)
                    > and calcium chloride (absorber) (or some other chemical) or water and
                    silica
                    > gel. The water and silica gel seems most promising to me. Ammonia is too
                    > dangerous to have inside my house and it makes it difficult to work out a
                    > system in which I can keep it outside. Water, however, is safe and when it
                    > evaporates, absorbs a great deal of heat.
                    >
                    > There is also a solid state alternative that I have not had much
                    opportunity
                    > to explore. They use solid state refrigerators in small outdoor coolers.
                    > When you pass a 12V current through the diode, one side gets hot and the
                    > other side gets cool. Perhaps, we could use the hot side to pre-heat our
                    > water to the hot water heater and the cold side to chill water that could
                    be
                    > used to cool the house, if needed. The unit could be attached to solar
                    > panels that produce the 12V current. The hotter it is outside, the harder
                    > the unit works. I like that!
                    >
                    > Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                    > http://www.adsorptionchiller.com/
                    >
                    > Billy Bell
                    > PO Box 926
                    > Fulshear, Texas 77441-0926
                    >
                    > 713-439-1115 Telephone
                    > 281-346-0994 Fax
                    > wmb@...
                    >
                    >
                    >
                    >
                    >
                    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                    >
                    >





                    Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/








                    Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  • Claude Foster
                    Kim, I will do some calculations for you if you will contact me directly. ccfoster@lan-inc.com
                    Message 9 of 28 , Sep 4, 2001
                      Kim,

                      I will do some calculations for you if you will contact me directly.

                      ccfoster@...



                      > -----Original Message-----
                      > From: Kim & Garth Travis [SMTP:gartht@...]
                      > Sent: Saturday, September 01, 2001 7:16 AM
                      > To: hreg@yahoogroups.com
                      > Subject: Re: [hreg] Solar Air Conditioners
                      >
                      > Hi,
                      > I am planning using cooled water to cool a 1000 sq. ft. building. My
                      > circulating pump is from a 15' diameter swimming pool. I installed my
                      > pipe under a raised garden bed that is filled with plants that like wet
                      > feet. In the testing we have done on the garden bed water, we seem to
                      > be washing the heat away. The plans call for the cooling pipe to be
                      > installed at the 8' level on the walls as well as in the floor.
                      > Kim
                      >
                      > William M. Bell, Jr. wrote:
                      >
                      > > Robert:
                      > >
                      > > Thanks for the interest. I am not opposed to ammonia. It simply makes
                      > life a
                      > > little more complicated.
                      > >
                      > > I "designed" a system that used chilled water to cool and heated water
                      > to
                      > > heat. The main problem was that it required a rather large, insulated
                      > > holding tank. I proposed to use a concrete tank and bury it.
                      > >
                      > > I found a simpler design that used silica gel and water. It uses
                      > > solar-heated water to squeeze the water out of the silica gel. If you
                      > looked
                      > > at the web site that I listed, you can see a commercial application of
                      > such
                      > > a system. It has much going for it: few moving parts; no corrosive
                      > > chemicals; no excessive pressures or temperatures; and simple. The only
                      > > problem is that I can't find any residential applications and
                      > information is
                      > > scarce.
                      > >
                      > > Geothermal is cool, no pun intended. The main problem that I have
                      > > encountered is that it is expensive to drill several wells and there is
                      > also
                      > > a fear that you could contaminate your drinking water. That is
                      > geothermal
                      > > that uses water wells. I have also heard of geothermal that circulated
                      > water
                      > > through pipes located 10+ feet below ground. A friend of mine worked
                      > with a
                      > > company that uses directional drilling to dig the lines for fiber optic
                      > > cable and conduit. He thought that it would be an easy matter to use
                      > their
                      > > machine to drill the circulating lines. My biggest obstacle, is that I
                      > have
                      > > no idea how much line, etc that I would need. Lack of knowledge has
                      > stopped
                      > > me once again. My thought was that I could put a coil in my air
                      > conditioner
                      > > blower, before it got to the a/c coil, so that I could pre-cool my air.
                      > The
                      > > idea was that if it worked well enough, the a/c would not need to kick
                      > in. I
                      > > wanted to find a small circulating pump (again, I had no idea what size)
                      > and
                      > > have it run by a solar panel. The hotter it is outside, the more it
                      > pumps. I
                      > > have a friend in Lake Jackson who drilled several wells and used it to
                      > cool
                      > > his house. It worked OK for a while, but then he had problems with his
                      > > wells.
                      > >
                      > > Anyway, I think that this is an interesting area and we would all
                      > benefit
                      > > from sharing our knowledge.
                      > >
                      > > ----- Original Message -----
                      > > From: "Robert Johnston" <rjohnsto@...>
                      > > To: <hreg@yahoogroups.com>
                      > > Sent: Friday, August 31, 2001 6:14 PM
                      > > Subject: [hreg] Solar Air Conditioners
                      > >
                      > >
                      > >
                      > >> Between the Nigerian Scams and the Environmental Spams, the good stuff
                      > is
                      > >> hard to find here! However, there wasn't much comment on this note
                      > from
                      > >> Billy Bell except Kevin pointing out the inefficiencies of
                      > thermoelectric
                      > >> cooling (especially if tied to a solar cell!).
                      > >>
                      > >> However, it is an extremely interesting question and one I'd love to
                      > see
                      > >> more discussion on. This is obviously one of the main barriers to this
                      > >
                      > > area
                      > >
                      > >> ever achieving the kind of renewable energy freedom that some other
                      > parts
                      > >
                      > > of
                      > >
                      > >> the country can do. The use of water as an evaporative coolant OK in
                      > >> Arizona but not Houston--too humid already! In any case, even in a
                      > closed
                      > >> system it wouldn't make a good medium for an efficient A/C.
                      > >>
                      > >> Anybody want to comment on what they think has the greatest potential
                      > in
                      > >
                      > > our
                      > >
                      > >> area?
                      > >> Things that come to mind for me (besides ceiling fans, insulation,
                      > etc.)
                      > >> are:
                      > >>
                      > >> 1. Dessicators. I know that natural gas fired units are now used for
                      > >> commercial buildings in some locations. I don't know if any efficient
                      > >
                      > > solar
                      > >
                      > >> units have been designed. But if you could dry out the air, that would
                      > >
                      > > help
                      > >
                      > >> a lot. And then you might even be able to put a little cool water back
                      > in
                      > >> as evaporative coolant as in Arizona.
                      > >>
                      > >> 2. Geothermal units. I'm puzzled why these haven't taken off, unless
                      > it
                      > >
                      > > is
                      > >
                      > >> their installation expense. Why are they so expensive? Are they not
                      > >
                      > > good?
                      > >
                      > >> A local A/C guy told me there are lots of problems with mold and odor
                      > in
                      > >
                      > > the
                      > >
                      > >> heat pump part of the installation. I don't know if that is true. He
                      > is
                      > >> death on heat pumps **period** for that reason, and prefers straight
                      > >
                      > > A/C's.
                      > >
                      > >> But there is still something appealing to me of trying to cool
                      > compressed
                      > >> gas with ground temperature rather than air temperature medium. I've
                      > seen
                      > >> some of the numbers posted on the web (very high S.E.E.R.), but there
                      > is a
                      > >> lot of hype by vendors. Since these aren't that popular, is it because
                      > >
                      > > they
                      > >
                      > >> don't work that well in practice, or is it just the cost of
                      > installation?
                      > >> What is the payback period in this area, then? These are some
                      > questions
                      > >
                      > > I'd
                      > >
                      > >> like to see discussed.
                      > >>
                      > >> As far as ammonia goes, Billy--I know it is not nice stuff, but it used
                      > to
                      > >> be used in refrigerators long ago, so with proper engineering I guess
                      > it
                      > >
                      > > was
                      > >
                      > >> managed OK. (Before my time, so I have no first hand experience). I
                      > also
                      > >> know that TDC put some ammonia cooling systems on a couple of new
                      > warden's
                      > >> homes at the prison farm south of Lake Jackson on the corner of
                      > >> FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                      > >> optimally sloping roofs aimed towards the sun, and then on the rooftops
                      > >
                      > > were
                      > >
                      > >> solar collectors. They may have had solar hot water too--I don't
                      > >> recall--but I remember reading in the newspaper when they built them
                      > about
                      > >> their ammonia cooling systems. This would have been around 1981-85
                      > >> timeframe. I also know that the collectors are now gone, but I don't
                      > know
                      > >> why. It could just be that TDC didn't want to fuss with them--e.g., it
                      > >
                      > > may
                      > >
                      > >> have been environmentally "cool" (pun intended) to use solar on state
                      > >> institutions at that time, but the maintenance expense for handling
                      > such
                      > >
                      > > an
                      > >
                      > >> unusual system that was different than all the other onsite A/C's might
                      > >
                      > > have
                      > >
                      > >> caused rethinking of the project down the road. Or, it may be that the
                      > >> units just didn't hold up to use. I don't know, but I assume you could
                      > >
                      > > find
                      > >
                      > >> out more by asking around, or writing TDC.
                      > >>
                      > >> In any case, if any of you have some thoughts on the subject of solar
                      > or
                      > >> just more efficient air conditioning/cooling, why don't we see if we
                      > can
                      > >
                      > > get
                      > >
                      > >> a discussion going on this subject and enlighten ourselves?
                      > >>
                      > >> Robert Johnston
                      > >>
                      > >> -----Original Message-----
                      > >> From: William M. Bell, Jr. [mailto:wmb@...]
                      > >> Sent: Wednesday, August 29, 2001 9:23 AM
                      > >> To: hreg@yahoogroups.com
                      > >> Subject: Re: [hreg] Digest Number 281
                      > >>
                      > >>
                      > >>
                      > >>> Wow! What an email regarding the livestock industry and the whales.
                      > Who
                      > >>
                      > >> are
                      > >>
                      > >>> they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much
                      > for
                      > >>
                      > >> me.
                      > >>
                      > >>> Steve Stelzer
                      > >>
                      > >> I thought that livestock produced methane, which was a renewable? Just
                      > >> Kidding ; ) Although I appreciate information of this sort, I am more
                      > >> concerned that this discussion group stays on target.
                      > >>
                      > >> By the way, I have been doing a great deal of looking around in my
                      > spare
                      > >> time (which is not much) at solar air conditioners. There a number of
                      > >> alternatives out there. It sounds strange until you view solar as an
                      > >
                      > > energy
                      > >
                      > >> source (heat). Most solar air conditioners work by a process called
                      > >> adsorption. An efficient, economical solar a/c system, that could be
                      > used
                      > >
                      > > in
                      > >
                      > >> residential cooling would be an important contribution to renewable
                      > >
                      > > energy.
                      > >
                      > >> Think of the amount of heat generated in this city by a/c and the
                      > amount
                      > >
                      > > of
                      > >
                      > >> electricity that is wasted producing this heat.
                      > >>
                      > >> The adsorption units that I have looked at use either ammonia
                      > >
                      > > (refrigerant)
                      > >
                      > >> and calcium chloride (absorber) (or some other chemical) or water and
                      > >
                      > > silica
                      > >
                      > >> gel. The water and silica gel seems most promising to me. Ammonia is
                      > too
                      > >> dangerous to have inside my house and it makes it difficult to work out
                      > a
                      > >> system in which I can keep it outside. Water, however, is safe and when
                      > it
                      > >> evaporates, absorbs a great deal of heat.
                      > >>
                      > >> There is also a solid state alternative that I have not had much
                      > >
                      > > opportunity
                      > >
                      > >> to explore. They use solid state refrigerators in small outdoor
                      > coolers.
                      > >> When you pass a 12V current through the diode, one side gets hot and
                      > the
                      > >> other side gets cool. Perhaps, we could use the hot side to pre-heat
                      > our
                      > >> water to the hot water heater and the cold side to chill water that
                      > could
                      > >
                      > > be
                      > >
                      > >> used to cool the house, if needed. The unit could be attached to solar
                      > >> panels that produce the 12V current. The hotter it is outside, the
                      > harder
                      > >> the unit works. I like that!
                      > >>
                      > >> Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                      > >> http://www.adsorptionchiller.com/
                      > >>
                      > >> Billy Bell
                      > >> PO Box 926
                      > >> Fulshear, Texas 77441-0926
                      > >>
                      > >> 713-439-1115 Telephone
                      > >> 281-346-0994 Fax
                      > >> wmb@...
                      > >>
                      > >>
                      > >>
                      > >>
                      > >>
                      > >> Your use of Yahoo! Groups is subject to
                      > http://docs.yahoo.com/info/terms/
                      > >>
                      > >>
                      > >>
                      > >>
                      > >>
                      > >>
                      > >>
                      > >>
                      > >> Your use of Yahoo! Groups is subject to
                      > http://docs.yahoo.com/info/terms/
                      > >>
                      > >>
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > Your use of Yahoo! Groups is subject to
                      > http://docs.yahoo.com/info/terms/
                      >
                      >
                      >
                      >
                      >
                      > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                      >
                    • Mike Ewert
                      Here is a review paper I did a while back on solar AC and heat pumps. ... From: Robert Johnston [mailto:rjohnsto@brazosport.cc.tx.us] Sent: Friday, August 31,
                      Message 10 of 28 , Sep 4, 2001
                        Here is a review paper I did a while back on solar AC and heat pumps.


                        -----Original Message-----
                        From: Robert Johnston [mailto:rjohnsto@...]
                        Sent: Friday, August 31, 2001 6:14 PM
                        To: hreg@yahoogroups.com
                        Subject: [hreg] Solar Air Conditioners


                        Between the Nigerian Scams and the Environmental Spams, the good stuff is
                        hard to find here! However, there wasn't much comment on this note from
                        Billy Bell except Kevin pointing out the inefficiencies of thermoelectric
                        cooling (especially if tied to a solar cell!).

                        However, it is an extremely interesting question and one I'd love to see
                        more discussion on. This is obviously one of the main barriers to this area
                        ever achieving the kind of renewable energy freedom that some other parts of
                        the country can do. The use of water as an evaporative coolant OK in
                        Arizona but not Houston--too humid already! In any case, even in a closed
                        system it wouldn't make a good medium for an efficient A/C.

                        Anybody want to comment on what they think has the greatest potential in our
                        area?
                        Things that come to mind for me (besides ceiling fans, insulation, etc.)
                        are:

                        1. Dessicators. I know that natural gas fired units are now used for
                        commercial buildings in some locations. I don't know if any efficient solar
                        units have been designed. But if you could dry out the air, that would help
                        a lot. And then you might even be able to put a little cool water back in
                        as evaporative coolant as in Arizona.

                        2. Geothermal units. I'm puzzled why these haven't taken off, unless it is
                        their installation expense. Why are they so expensive? Are they not good?
                        A local A/C guy told me there are lots of problems with mold and odor in the
                        heat pump part of the installation. I don't know if that is true. He is
                        death on heat pumps **period** for that reason, and prefers straight A/C's.
                        But there is still something appealing to me of trying to cool compressed
                        gas with ground temperature rather than air temperature medium. I've seen
                        some of the numbers posted on the web (very high S.E.E.R.), but there is a
                        lot of hype by vendors. Since these aren't that popular, is it because they
                        don't work that well in practice, or is it just the cost of installation?
                        What is the payback period in this area, then? These are some questions I'd
                        like to see discussed.

                        As far as ammonia goes, Billy--I know it is not nice stuff, but it used to
                        be used in refrigerators long ago, so with proper engineering I guess it was
                        managed OK. (Before my time, so I have no first hand experience). I also
                        know that TDC put some ammonia cooling systems on a couple of new warden's
                        homes at the prison farm south of Lake Jackson on the corner of
                        FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                        optimally sloping roofs aimed towards the sun, and then on the rooftops were
                        solar collectors. They may have had solar hot water too--I don't
                        recall--but I remember reading in the newspaper when they built them about
                        their ammonia cooling systems. This would have been around 1981-85
                        timeframe. I also know that the collectors are now gone, but I don't know
                        why. It could just be that TDC didn't want to fuss with them--e.g., it may
                        have been environmentally "cool" (pun intended) to use solar on state
                        institutions at that time, but the maintenance expense for handling such an
                        unusual system that was different than all the other onsite A/C's might have
                        caused rethinking of the project down the road. Or, it may be that the
                        units just didn't hold up to use. I don't know, but I assume you could find
                        out more by asking around, or writing TDC.

                        In any case, if any of you have some thoughts on the subject of solar or
                        just more efficient air conditioning/cooling, why don't we see if we can get
                        a discussion going on this subject and enlighten ourselves?

                        Robert Johnston

                        -----Original Message-----
                        From: William M. Bell, Jr. [mailto:wmb@...]
                        Sent: Wednesday, August 29, 2001 9:23 AM
                        To: hreg@yahoogroups.com
                        Subject: Re: [hreg] Digest Number 281


                        > Wow! What an email regarding the livestock industry and the whales. Who
                        are
                        > they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much for
                        me.
                        >
                        > Steve Stelzer

                        I thought that livestock produced methane, which was a renewable? Just
                        Kidding ; ) Although I appreciate information of this sort, I am more
                        concerned that this discussion group stays on target.

                        By the way, I have been doing a great deal of looking around in my spare
                        time (which is not much) at solar air conditioners. There a number of
                        alternatives out there. It sounds strange until you view solar as an energy
                        source (heat). Most solar air conditioners work by a process called
                        adsorption. An efficient, economical solar a/c system, that could be used in
                        residential cooling would be an important contribution to renewable energy.
                        Think of the amount of heat generated in this city by a/c and the amount of
                        electricity that is wasted producing this heat.

                        The adsorption units that I have looked at use either ammonia (refrigerant)
                        and calcium chloride (absorber) (or some other chemical) or water and silica
                        gel. The water and silica gel seems most promising to me. Ammonia is too
                        dangerous to have inside my house and it makes it difficult to work out a
                        system in which I can keep it outside. Water, however, is safe and when it
                        evaporates, absorbs a great deal of heat.

                        There is also a solid state alternative that I have not had much opportunity
                        to explore. They use solid state refrigerators in small outdoor coolers.
                        When you pass a 12V current through the diode, one side gets hot and the
                        other side gets cool. Perhaps, we could use the hot side to pre-heat our
                        water to the hot water heater and the cold side to chill water that could be
                        used to cool the house, if needed. The unit could be attached to solar
                        panels that produce the 12V current. The hotter it is outside, the harder
                        the unit works. I like that!

                        Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                        http://www.adsorptionchiller.com/

                        Billy Bell
                        PO Box 926
                        Fulshear, Texas 77441-0926

                        713-439-1115 Telephone
                        281-346-0994 Fax
                        wmb@...





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                        Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                      • Robert Johnston
                        At a tradeshow in Houston a few years ago I met and chatted briefly with LaVerne Williams. I asked his opinion about cool tubes --those buried PVC pipes that
                        Message 11 of 28 , Sep 5, 2001
                          At a tradeshow in Houston a few years ago I met and chatted briefly with
                          LaVerne
                          Williams. I asked his opinion about "cool tubes"--those buried PVC pipes
                          that run
                          for a length underground and allow you to bring outside air into the home
                          after
                          letting it cool in indirect contact with the earth. My recollection of his
                          comment
                          was that it was an ideal breeding ground for Legionnaire's Disease, and he
                          wouldn't
                          recommend it. Since I had seen such a solution recommended for our area in
                          the
                          "Earthship" books, his comment made quite an impression on me and left me
                          wondering
                          what kind of cooling WOULD work, and that ongoing question is why I started
                          this
                          thread.

                          I'm wondering what kind of cooling Kim has in mind. In particular, I'm
                          wondering,
                          If you live in a hot humid area, is ANY kind of cooling based on bringing
                          cold air
                          or water into the house WITHOUT also having dehumidificatio built into the
                          cooling
                          system setting oneself up for mold, mildew and perhaps Legionnaire's
                          Disease? e.g.,
                          suppose you could use water pipes or any other technology to cool the walls
                          and floor
                          of your home to a pleasant 70?C and keep it there day and night. While in
                          West Texas
                          that would do quite nicely, would it fail miserably in Houston because there
                          would
                          be lots of condensation on the walls and floor, with lots of mold and mildew
                          on and
                          in the walls? (A vapor barrier would be meaningless if you are not drying
                          the air
                          inside).

                          LaVerne Williams, are you reading this? Did I summarize your comments
                          accurately?
                          Would you care to comment on the futility of ANY approaches to cooling a
                          house here
                          without simultaneously providing dehumidification? As long as the house
                          stays near
                          ambient temperature I would think things would be OK, but the concern is
                          that you
                          might cool the house below ambient in a humid environment. Care to comment
                          on what
                          appears to be Kim's plan to cool a building with cold water pipes?

                          Robert

                          -----Original Message-----
                          From: Claude Foster [mailto:ccfoster@...]
                          Sent: Tuesday, September 04, 2001 7:51 AM
                          To: 'hreg@yahoogroups.com'
                          Subject: RE: [hreg] Solar Air Conditioners


                          Kim,

                          I will do some calculations for you if you will contact me directly.

                          ccfoster@...



                          > -----Original Message-----
                          > From: Kim & Garth Travis [SMTP:gartht@...]
                          > Sent: Saturday, September 01, 2001 7:16 AM
                          > To: hreg@yahoogroups.com
                          > Subject: Re: [hreg] Solar Air Conditioners
                          >
                          > Hi,
                          > I am planning using cooled water to cool a 1000 sq. ft. building. My
                          > circulating pump is from a 15' diameter swimming pool. I installed my
                          > pipe under a raised garden bed that is filled with plants that like wet
                          > feet. In the testing we have done on the garden bed water, we seem to
                          > be washing the heat away. The plans call for the cooling pipe to be
                          > installed at the 8' level on the walls as well as in the floor.
                          > Kim
                          >
                          > William M. Bell, Jr. wrote:
                          >
                          > > Robert:
                          > >
                          > > Thanks for the interest. I am not opposed to ammonia. It simply makes
                          > life a
                          > > little more complicated.
                          > >
                          > > I "designed" a system that used chilled water to cool and heated water
                          > to
                          > > heat. The main problem was that it required a rather large, insulated
                          > > holding tank. I proposed to use a concrete tank and bury it.
                          > >
                          > > I found a simpler design that used silica gel and water. It uses
                          > > solar-heated water to squeeze the water out of the silica gel. If you
                          > looked
                          > > at the web site that I listed, you can see a commercial application of
                          > such
                          > > a system. It has much going for it: few moving parts; no corrosive
                          > > chemicals; no excessive pressures or temperatures; and simple. The only
                          > > problem is that I can't find any residential applications and
                          > information is
                          > > scarce.
                          > >
                          > > Geothermal is cool, no pun intended. The main problem that I have
                          > > encountered is that it is expensive to drill several wells and there is
                          > also
                          > > a fear that you could contaminate your drinking water. That is
                          > geothermal
                          > > that uses water wells. I have also heard of geothermal that circulated
                          > water
                          > > through pipes located 10+ feet below ground. A friend of mine worked
                          > with a
                          > > company that uses directional drilling to dig the lines for fiber optic
                          > > cable and conduit. He thought that it would be an easy matter to use
                          > their
                          > > machine to drill the circulating lines. My biggest obstacle, is that I
                          > have
                          > > no idea how much line, etc that I would need. Lack of knowledge has
                          > stopped
                          > > me once again. My thought was that I could put a coil in my air
                          > conditioner
                          > > blower, before it got to the a/c coil, so that I could pre-cool my air.
                          > The
                          > > idea was that if it worked well enough, the a/c would not need to kick
                          > in. I
                          > > wanted to find a small circulating pump (again, I had no idea what size)
                          > and
                          > > have it run by a solar panel. The hotter it is outside, the more it
                          > pumps. I
                          > > have a friend in Lake Jackson who drilled several wells and used it to
                          > cool
                          > > his house. It worked OK for a while, but then he had problems with his
                          > > wells.
                          > >
                          > > Anyway, I think that this is an interesting area and we would all
                          > benefit
                          > > from sharing our knowledge.
                          > >
                          > > ----- Original Message -----
                          > > From: "Robert Johnston" <rjohnsto@...>
                          > > To: <hreg@yahoogroups.com>
                          > > Sent: Friday, August 31, 2001 6:14 PM
                          > > Subject: [hreg] Solar Air Conditioners
                          > >
                          > >
                          > >
                          > >> Between the Nigerian Scams and the Environmental Spams, the good stuff
                          > is
                          > >> hard to find here! However, there wasn't much comment on this note
                          > from
                          > >> Billy Bell except Kevin pointing out the inefficiencies of
                          > thermoelectric
                          > >> cooling (especially if tied to a solar cell!).
                          > >>
                          > >> However, it is an extremely interesting question and one I'd love to
                          > see
                          > >> more discussion on. This is obviously one of the main barriers to this
                          > >
                          > > area
                          > >
                          > >> ever achieving the kind of renewable energy freedom that some other
                          > parts
                          > >
                          > > of
                          > >
                          > >> the country can do. The use of water as an evaporative coolant OK in
                          > >> Arizona but not Houston--too humid already! In any case, even in a
                          > closed
                          > >> system it wouldn't make a good medium for an efficient A/C.
                          > >>
                          > >> Anybody want to comment on what they think has the greatest potential
                          > in
                          > >
                          > > our
                          > >
                          > >> area?
                          > >> Things that come to mind for me (besides ceiling fans, insulation,
                          > etc.)
                          > >> are:
                          > >>
                          > >> 1. Dessicators. I know that natural gas fired units are now used for
                          > >> commercial buildings in some locations. I don't know if any efficient
                          > >
                          > > solar
                          > >
                          > >> units have been designed. But if you could dry out the air, that would
                          > >
                          > > help
                          > >
                          > >> a lot. And then you might even be able to put a little cool water back
                          > in
                          > >> as evaporative coolant as in Arizona.
                          > >>
                          > >> 2. Geothermal units. I'm puzzled why these haven't taken off, unless
                          > it
                          > >
                          > > is
                          > >
                          > >> their installation expense. Why are they so expensive? Are they not
                          > >
                          > > good?
                          > >
                          > >> A local A/C guy told me there are lots of problems with mold and odor
                          > in
                          > >
                          > > the
                          > >
                          > >> heat pump part of the installation. I don't know if that is true. He
                          > is
                          > >> death on heat pumps **period** for that reason, and prefers straight
                          > >
                          > > A/C's.
                          > >
                          > >> But there is still something appealing to me of trying to cool
                          > compressed
                          > >> gas with ground temperature rather than air temperature medium. I've
                          > seen
                          > >> some of the numbers posted on the web (very high S.E.E.R.), but there
                          > is a
                          > >> lot of hype by vendors. Since these aren't that popular, is it because
                          > >
                          > > they
                          > >
                          > >> don't work that well in practice, or is it just the cost of
                          > installation?
                          > >> What is the payback period in this area, then? These are some
                          > questions
                          > >
                          > > I'd
                          > >
                          > >> like to see discussed.
                          > >>
                          > >> As far as ammonia goes, Billy--I know it is not nice stuff, but it used
                          > to
                          > >> be used in refrigerators long ago, so with proper engineering I guess
                          > it
                          > >
                          > > was
                          > >
                          > >> managed OK. (Before my time, so I have no first hand experience). I
                          > also
                          > >> know that TDC put some ammonia cooling systems on a couple of new
                          > warden's
                          > >> homes at the prison farm south of Lake Jackson on the corner of
                          > >> FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                          > >> optimally sloping roofs aimed towards the sun, and then on the rooftops
                          > >
                          > > were
                          > >
                          > >> solar collectors. They may have had solar hot water too--I don't
                          > >> recall--but I remember reading in the newspaper when they built them
                          > about
                          > >> their ammonia cooling systems. This would have been around 1981-85
                          > >> timeframe. I also know that the collectors are now gone, but I don't
                          > know
                          > >> why. It could just be that TDC didn't want to fuss with them--e.g., it
                          > >
                          > > may
                          > >
                          > >> have been environmentally "cool" (pun intended) to use solar on state
                          > >> institutions at that time, but the maintenance expense for handling
                          > such
                          > >
                          > > an
                          > >
                          > >> unusual system that was different than all the other onsite A/C's might
                          > >
                          > > have
                          > >
                          > >> caused rethinking of the project down the road. Or, it may be that the
                          > >> units just didn't hold up to use. I don't know, but I assume you could
                          > >
                          > > find
                          > >
                          > >> out more by asking around, or writing TDC.
                          > >>
                          > >> In any case, if any of you have some thoughts on the subject of solar
                          > or
                          > >> just more efficient air conditioning/cooling, why don't we see if we
                          > can
                          > >
                          > > get
                          > >
                          > >> a discussion going on this subject and enlighten ourselves?
                          > >>
                          > >> Robert Johnston
                          > >>
                          > >> -----Original Message-----
                          > >> From: William M. Bell, Jr. [mailto:wmb@...]
                          > >> Sent: Wednesday, August 29, 2001 9:23 AM
                          > >> To: hreg@yahoogroups.com
                          > >> Subject: Re: [hreg] Digest Number 281
                          > >>
                          > >>
                          > >>
                          > >>> Wow! What an email regarding the livestock industry and the whales.
                          > Who
                          > >>
                          > >> are
                          > >>
                          > >>> they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much
                          > for
                          > >>
                          > >> me.
                          > >>
                          > >>> Steve Stelzer
                          > >>
                          > >> I thought that livestock produced methane, which was a renewable? Just
                          > >> Kidding ; ) Although I appreciate information of this sort, I am more
                          > >> concerned that this discussion group stays on target.
                          > >>
                          > >> By the way, I have been doing a great deal of looking around in my
                          > spare
                          > >> time (which is not much) at solar air conditioners. There a number of
                          > >> alternatives out there. It sounds strange until you view solar as an
                          > >
                          > > energy
                          > >
                          > >> source (heat). Most solar air conditioners work by a process called
                          > >> adsorption. An efficient, economical solar a/c system, that could be
                          > used
                          > >
                          > > in
                          > >
                          > >> residential cooling would be an important contribution to renewable
                          > >
                          > > energy.
                          > >
                          > >> Think of the amount of heat generated in this city by a/c and the
                          > amount
                          > >
                          > > of
                          > >
                          > >> electricity that is wasted producing this heat.
                          > >>
                          > >> The adsorption units that I have looked at use either ammonia
                          > >
                          > > (refrigerant)
                          > >
                          > >> and calcium chloride (absorber) (or some other chemical) or water and
                          > >
                          > > silica
                          > >
                          > >> gel. The water and silica gel seems most promising to me. Ammonia is
                          > too
                          > >> dangerous to have inside my house and it makes it difficult to work out
                          > a
                          > >> system in which I can keep it outside. Water, however, is safe and when
                          > it
                          > >> evaporates, absorbs a great deal of heat.
                          > >>
                          > >> There is also a solid state alternative that I have not had much
                          > >
                          > > opportunity
                          > >
                          > >> to explore. They use solid state refrigerators in small outdoor
                          > coolers.
                          > >> When you pass a 12V current through the diode, one side gets hot and
                          > the
                          > >> other side gets cool. Perhaps, we could use the hot side to pre-heat
                          > our
                          > >> water to the hot water heater and the cold side to chill water that
                          > could
                          > >
                          > > be
                          > >
                          > >> used to cool the house, if needed. The unit could be attached to solar
                          > >> panels that produce the 12V current. The hotter it is outside, the
                          > harder
                          > >> the unit works. I like that!
                          > >>
                          > >> Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                          > >> http://www.adsorptionchiller.com/
                          > >>
                          > >> Billy Bell
                          > >> PO Box 926
                          > >> Fulshear, Texas 77441-0926
                          > >>
                          > >> 713-439-1115 Telephone
                          > >> 281-346-0994 Fax
                          > >> wmb@...
                          > >>
                          > >>
                          > >>
                          > >>
                          > >>
                          > >> Your use of Yahoo! Groups is subject to
                          > http://docs.yahoo.com/info/terms/
                          > >>
                          > >>
                          > >>
                          > >>
                          > >>
                          > >>
                          > >>
                          > >>
                          > >> Your use of Yahoo! Groups is subject to
                          > http://docs.yahoo.com/info/terms/
                          > >>
                          > >>
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > > Your use of Yahoo! Groups is subject to
                          > http://docs.yahoo.com/info/terms/
                          >
                          >
                          >
                          >
                          >
                          > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                          >




                          Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                        • Robert Johnston
                          Correction: Make that a pleasant 70?F ! ... From: Robert Johnston [mailto:rjohnsto@brazosport.cc.tx.us] Sent: Wednesday, September 05, 2001 7:01 AM To:
                          Message 12 of 28 , Sep 5, 2001
                            Correction: Make that "a pleasant 70?F"!

                            -----Original Message-----
                            From: Robert Johnston [mailto:rjohnsto@...]
                            Sent: Wednesday, September 05, 2001 7:01 AM
                            To: hreg@yahoogroups.com
                            Subject: RE: [hreg] Solar Air Conditioners (LaVerne Williams?)


                            At a tradeshow in Houston a few years ago I met and chatted briefly with
                            LaVerne
                            Williams. I asked his opinion about "cool tubes"--those buried PVC pipes
                            that run
                            for a length underground and allow you to bring outside air into the home
                            after
                            letting it cool in indirect contact with the earth. My recollection of his
                            comment
                            was that it was an ideal breeding ground for Legionnaire's Disease, and he
                            wouldn't
                            recommend it. Since I had seen such a solution recommended for our area in
                            the
                            "Earthship" books, his comment made quite an impression on me and left me
                            wondering
                            what kind of cooling WOULD work, and that ongoing question is why I started
                            this
                            thread.

                            I'm wondering what kind of cooling Kim has in mind. In particular, I'm
                            wondering,
                            If you live in a hot humid area, is ANY kind of cooling based on bringing
                            cold air
                            or water into the house WITHOUT also having dehumidificatio built into the
                            cooling
                            system setting oneself up for mold, mildew and perhaps Legionnaire's
                            Disease? e.g.,
                            suppose you could use water pipes or any other technology to cool the walls
                            and floor
                            of your home to a pleasant 70?C and keep it there day and night. While in
                            West Texas
                            that would do quite nicely, would it fail miserably in Houston because there
                            would
                            be lots of condensation on the walls and floor, with lots of mold and mildew
                            on and
                            in the walls? (A vapor barrier would be meaningless if you are not drying
                            the air
                            inside).

                            LaVerne Williams, are you reading this? Did I summarize your comments
                            accurately?
                            Would you care to comment on the futility of ANY approaches to cooling a
                            house here
                            without simultaneously providing dehumidification? As long as the house
                            stays near
                            ambient temperature I would think things would be OK, but the concern is
                            that you
                            might cool the house below ambient in a humid environment. Care to comment
                            on what
                            appears to be Kim's plan to cool a building with cold water pipes?

                            Robert

                            -----Original Message-----
                            From: Claude Foster [mailto:ccfoster@...]
                            Sent: Tuesday, September 04, 2001 7:51 AM
                            To: 'hreg@yahoogroups.com'
                            Subject: RE: [hreg] Solar Air Conditioners


                            Kim,

                            I will do some calculations for you if you will contact me directly.

                            ccfoster@...



                            > -----Original Message-----
                            > From: Kim & Garth Travis [SMTP:gartht@...]
                            > Sent: Saturday, September 01, 2001 7:16 AM
                            > To: hreg@yahoogroups.com
                            > Subject: Re: [hreg] Solar Air Conditioners
                            >
                            > Hi,
                            > I am planning using cooled water to cool a 1000 sq. ft. building. My
                            > circulating pump is from a 15' diameter swimming pool. I installed my
                            > pipe under a raised garden bed that is filled with plants that like wet
                            > feet. In the testing we have done on the garden bed water, we seem to
                            > be washing the heat away. The plans call for the cooling pipe to be
                            > installed at the 8' level on the walls as well as in the floor.
                            > Kim
                            >
                            > William M. Bell, Jr. wrote:
                            >
                            > > Robert:
                            > >
                            > > Thanks for the interest. I am not opposed to ammonia. It simply makes
                            > life a
                            > > little more complicated.
                            > >
                            > > I "designed" a system that used chilled water to cool and heated water
                            > to
                            > > heat. The main problem was that it required a rather large, insulated
                            > > holding tank. I proposed to use a concrete tank and bury it.
                            > >
                            > > I found a simpler design that used silica gel and water. It uses
                            > > solar-heated water to squeeze the water out of the silica gel. If you
                            > looked
                            > > at the web site that I listed, you can see a commercial application of
                            > such
                            > > a system. It has much going for it: few moving parts; no corrosive
                            > > chemicals; no excessive pressures or temperatures; and simple. The only
                            > > problem is that I can't find any residential applications and
                            > information is
                            > > scarce.
                            > >
                            > > Geothermal is cool, no pun intended. The main problem that I have
                            > > encountered is that it is expensive to drill several wells and there is
                            > also
                            > > a fear that you could contaminate your drinking water. That is
                            > geothermal
                            > > that uses water wells. I have also heard of geothermal that circulated
                            > water
                            > > through pipes located 10+ feet below ground. A friend of mine worked
                            > with a
                            > > company that uses directional drilling to dig the lines for fiber optic
                            > > cable and conduit. He thought that it would be an easy matter to use
                            > their
                            > > machine to drill the circulating lines. My biggest obstacle, is that I
                            > have
                            > > no idea how much line, etc that I would need. Lack of knowledge has
                            > stopped
                            > > me once again. My thought was that I could put a coil in my air
                            > conditioner
                            > > blower, before it got to the a/c coil, so that I could pre-cool my air.
                            > The
                            > > idea was that if it worked well enough, the a/c would not need to kick
                            > in. I
                            > > wanted to find a small circulating pump (again, I had no idea what size)
                            > and
                            > > have it run by a solar panel. The hotter it is outside, the more it
                            > pumps. I
                            > > have a friend in Lake Jackson who drilled several wells and used it to
                            > cool
                            > > his house. It worked OK for a while, but then he had problems with his
                            > > wells.
                            > >
                            > > Anyway, I think that this is an interesting area and we would all
                            > benefit
                            > > from sharing our knowledge.
                            > >
                            > > ----- Original Message -----
                            > > From: "Robert Johnston" <rjohnsto@...>
                            > > To: <hreg@yahoogroups.com>
                            > > Sent: Friday, August 31, 2001 6:14 PM
                            > > Subject: [hreg] Solar Air Conditioners
                            > >
                            > >
                            > >
                            > >> Between the Nigerian Scams and the Environmental Spams, the good stuff
                            > is
                            > >> hard to find here! However, there wasn't much comment on this note
                            > from
                            > >> Billy Bell except Kevin pointing out the inefficiencies of
                            > thermoelectric
                            > >> cooling (especially if tied to a solar cell!).
                            > >>
                            > >> However, it is an extremely interesting question and one I'd love to
                            > see
                            > >> more discussion on. This is obviously one of the main barriers to this
                            > >
                            > > area
                            > >
                            > >> ever achieving the kind of renewable energy freedom that some other
                            > parts
                            > >
                            > > of
                            > >
                            > >> the country can do. The use of water as an evaporative coolant OK in
                            > >> Arizona but not Houston--too humid already! In any case, even in a
                            > closed
                            > >> system it wouldn't make a good medium for an efficient A/C.
                            > >>
                            > >> Anybody want to comment on what they think has the greatest potential
                            > in
                            > >
                            > > our
                            > >
                            > >> area?
                            > >> Things that come to mind for me (besides ceiling fans, insulation,
                            > etc.)
                            > >> are:
                            > >>
                            > >> 1. Dessicators. I know that natural gas fired units are now used for
                            > >> commercial buildings in some locations. I don't know if any efficient
                            > >
                            > > solar
                            > >
                            > >> units have been designed. But if you could dry out the air, that would
                            > >
                            > > help
                            > >
                            > >> a lot. And then you might even be able to put a little cool water back
                            > in
                            > >> as evaporative coolant as in Arizona.
                            > >>
                            > >> 2. Geothermal units. I'm puzzled why these haven't taken off, unless
                            > it
                            > >
                            > > is
                            > >
                            > >> their installation expense. Why are they so expensive? Are they not
                            > >
                            > > good?
                            > >
                            > >> A local A/C guy told me there are lots of problems with mold and odor
                            > in
                            > >
                            > > the
                            > >
                            > >> heat pump part of the installation. I don't know if that is true. He
                            > is
                            > >> death on heat pumps **period** for that reason, and prefers straight
                            > >
                            > > A/C's.
                            > >
                            > >> But there is still something appealing to me of trying to cool
                            > compressed
                            > >> gas with ground temperature rather than air temperature medium. I've
                            > seen
                            > >> some of the numbers posted on the web (very high S.E.E.R.), but there
                            > is a
                            > >> lot of hype by vendors. Since these aren't that popular, is it because
                            > >
                            > > they
                            > >
                            > >> don't work that well in practice, or is it just the cost of
                            > installation?
                            > >> What is the payback period in this area, then? These are some
                            > questions
                            > >
                            > > I'd
                            > >
                            > >> like to see discussed.
                            > >>
                            > >> As far as ammonia goes, Billy--I know it is not nice stuff, but it used
                            > to
                            > >> be used in refrigerators long ago, so with proper engineering I guess
                            > it
                            > >
                            > > was
                            > >
                            > >> managed OK. (Before my time, so I have no first hand experience). I
                            > also
                            > >> know that TDC put some ammonia cooling systems on a couple of new
                            > warden's
                            > >> homes at the prison farm south of Lake Jackson on the corner of
                            > >> FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                            > >> optimally sloping roofs aimed towards the sun, and then on the rooftops
                            > >
                            > > were
                            > >
                            > >> solar collectors. They may have had solar hot water too--I don't
                            > >> recall--but I remember reading in the newspaper when they built them
                            > about
                            > >> their ammonia cooling systems. This would have been around 1981-85
                            > >> timeframe. I also know that the collectors are now gone, but I don't
                            > know
                            > >> why. It could just be that TDC didn't want to fuss with them--e.g., it
                            > >
                            > > may
                            > >
                            > >> have been environmentally "cool" (pun intended) to use solar on state
                            > >> institutions at that time, but the maintenance expense for handling
                            > such
                            > >
                            > > an
                            > >
                            > >> unusual system that was different than all the other onsite A/C's might
                            > >
                            > > have
                            > >
                            > >> caused rethinking of the project down the road. Or, it may be that the
                            > >> units just didn't hold up to use. I don't know, but I assume you could
                            > >
                            > > find
                            > >
                            > >> out more by asking around, or writing TDC.
                            > >>
                            > >> In any case, if any of you have some thoughts on the subject of solar
                            > or
                            > >> just more efficient air conditioning/cooling, why don't we see if we
                            > can
                            > >
                            > > get
                            > >
                            > >> a discussion going on this subject and enlighten ourselves?
                            > >>
                            > >> Robert Johnston
                            > >>
                            > >> -----Original Message-----
                            > >> From: William M. Bell, Jr. [mailto:wmb@...]
                            > >> Sent: Wednesday, August 29, 2001 9:23 AM
                            > >> To: hreg@yahoogroups.com
                            > >> Subject: Re: [hreg] Digest Number 281
                            > >>
                            > >>
                            > >>
                            > >>> Wow! What an email regarding the livestock industry and the whales.
                            > Who
                            > >>
                            > >> are
                            > >>
                            > >>> they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much
                            > for
                            > >>
                            > >> me.
                            > >>
                            > >>> Steve Stelzer
                            > >>
                            > >> I thought that livestock produced methane, which was a renewable? Just
                            > >> Kidding ; ) Although I appreciate information of this sort, I am more
                            > >> concerned that this discussion group stays on target.
                            > >>
                            > >> By the way, I have been doing a great deal of looking around in my
                            > spare
                            > >> time (which is not much) at solar air conditioners. There a number of
                            > >> alternatives out there. It sounds strange until you view solar as an
                            > >
                            > > energy
                            > >
                            > >> source (heat). Most solar air conditioners work by a process called
                            > >> adsorption. An efficient, economical solar a/c system, that could be
                            > used
                            > >
                            > > in
                            > >
                            > >> residential cooling would be an important contribution to renewable
                            > >
                            > > energy.
                            > >
                            > >> Think of the amount of heat generated in this city by a/c and the
                            > amount
                            > >
                            > > of
                            > >
                            > >> electricity that is wasted producing this heat.
                            > >>
                            > >> The adsorption units that I have looked at use either ammonia
                            > >
                            > > (refrigerant)
                            > >
                            > >> and calcium chloride (absorber) (or some other chemical) or water and
                            > >
                            > > silica
                            > >
                            > >> gel. The water and silica gel seems most promising to me. Ammonia is
                            > too
                            > >> dangerous to have inside my house and it makes it difficult to work out
                            > a
                            > >> system in which I can keep it outside. Water, however, is safe and when
                            > it
                            > >> evaporates, absorbs a great deal of heat.
                            > >>
                            > >> There is also a solid state alternative that I have not had much
                            > >
                            > > opportunity
                            > >
                            > >> to explore. They use solid state refrigerators in small outdoor
                            > coolers.
                            > >> When you pass a 12V current through the diode, one side gets hot and
                            > the
                            > >> other side gets cool. Perhaps, we could use the hot side to pre-heat
                            > our
                            > >> water to the hot water heater and the cold side to chill water that
                            > could
                            > >
                            > > be
                            > >
                            > >> used to cool the house, if needed. The unit could be attached to solar
                            > >> panels that produce the 12V current. The hotter it is outside, the
                            > harder
                            > >> the unit works. I like that!
                            > >>
                            > >> Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                            > >> http://www.adsorptionchiller.com/
                            > >>
                            > >> Billy Bell
                            > >> PO Box 926
                            > >> Fulshear, Texas 77441-0926
                            > >>
                            > >> 713-439-1115 Telephone
                            > >> 281-346-0994 Fax
                            > >> wmb@...
                            > >>
                            > >>
                            > >>
                            > >>
                            > >>
                            > >> Your use of Yahoo! Groups is subject to
                            > http://docs.yahoo.com/info/terms/
                            > >>
                            > >>
                            > >>
                            > >>
                            > >>
                            > >>
                            > >>
                            > >>
                            > >> Your use of Yahoo! Groups is subject to
                            > http://docs.yahoo.com/info/terms/
                            > >>
                            > >>
                            > >
                            > >
                            > >
                            > >
                            > >
                            > >
                            > > Your use of Yahoo! Groups is subject to
                            > http://docs.yahoo.com/info/terms/
                            >
                            >
                            >
                            >
                            >
                            > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                            >




                            Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/








                            Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                          • Kim & Garth Travis
                            Hi, ... I am using hydronics, an idea I got from Roth company on the web. PEX hose set in the floor and on the perimeter walls at the 8 height. Roth is
                            Message 13 of 28 , Sep 5, 2001
                              Hi,




                              > I'm wondering what kind of cooling Kim has in mind.

                              I am using hydronics, an idea I got from Roth company on the web. PEX
                              hose set in the floor and on the perimeter walls at the 8' height. Roth
                              is using such systems commercially and has an extensive web site. At
                              roth.com I think.

                              In particular, I'm
                              > wondering,
                              > If you live in a hot humid area,

                              I live 100 miles north-northwest of Houston.

                              is ANY kind of cooling based on bringing
                              > cold air
                              > or water into the house WITHOUT also having dehumidificatio built into the
                              > cooling
                              > system setting oneself up for mold, mildew and perhaps Legionnaire's
                              > Disease? e.g.,
                              > suppose you could use water pipes or any other technology to cool the walls
                              > and floor
                              > of your home to a pleasant 70?C and keep it there day and night.

                              We may need to bring in a dehumidifier, but I like my home at 50%
                              humidity. In Canada we used humidifiers to raise it this high.
                              Anything below this, we find uncomfortable. I am sorry, but I do not
                              find 70 degrees comfortable. The joy of living in Texas is I never need
                              to be cool or cold again. We are ranchers and work outside, a
                              temperature of 76 to 78 is comfortable to us. Our guest room has a
                              separate control so company can sleep in cooler temperatures. [We are
                              putting in a well screened sleeping porch for most of the year]

                              Our closets are 6" deeper than normal to allow air circulation. We do
                              not use wall to wall carpet, only area rugs. The big trick is to have a
                              super insulated building with wide porches, good ventilation and never
                              let it get hot. We first looked at the historical buildings in Texas and
                              how they kept them cool without electricity. Then we tried to design as
                              many of those ideas as possible into our buildings so our cooling
                              demands are not those of a normal tract home.

                              The temperature difference between the cooling and ambient temperatures
                              can not be too great, [say over 15 degrees] or you have a real problem.
                              The water we are using to cool is 65 degrees. The cool water comes in at
                              the wall, where it has a drip tray built under it, then circulates in
                              the floor before exiting.

                              If we ever let it get hot in the building, we would have to use some
                              window units or something to cool the building or wait a long time to
                              gradually lower the temperature. We have not built our main house yet,
                              we are working on our shops and installing all of our ideas there, first.


                              (A vapor barrier would be meaningless if you are not drying
                              > the air
                              > inside).

                              We do not use vapor barriers as our buildings are fibrous adobe.

                              >
                              > LaVerne Williams, are you reading this? Did I summarize your comments
                              > accurately?
                              > Would you care to comment on the futility of ANY approaches to cooling a
                              > house here
                              > without simultaneously providing dehumidification? As long as the house
                              > stays near
                              > ambient temperature I would think things would be OK, but the concern is
                              > that you
                              > might cool the house below ambient in a humid environment. Care to comment
                              > on what
                              > appears to be Kim's plan to cool a building with cold water pipes?
                              >
                              > Robert
                              >
                              > -----Original Message-----
                              > From: Claude Foster [mailto:ccfoster@...]
                              > Sent: Tuesday, September 04, 2001 7:51 AM
                              > To: 'hreg@yahoogroups.com'
                              > Subject: RE: [hreg] Solar Air Conditioners
                              >
                              >
                              > Kim,
                              >
                              > I will do some calculations for you if you will contact me directly.
                              >
                              > ccfoster@...
                              >
                              >
                              >
                              >
                              >> -----Original Message-----
                              >> From: Kim & Garth Travis [SMTP:gartht@...]
                              >> Sent: Saturday, September 01, 2001 7:16 AM
                              >> To: hreg@yahoogroups.com
                              >> Subject: Re: [hreg] Solar Air Conditioners
                              >>
                              >> Hi,
                              >> I am planning using cooled water to cool a 1000 sq. ft. building. My
                              >> circulating pump is from a 15' diameter swimming pool. I installed my
                              >> pipe under a raised garden bed that is filled with plants that like wet
                              >> feet. In the testing we have done on the garden bed water, we seem to
                              >> be washing the heat away. The plans call for the cooling pipe to be
                              >> installed at the 8' level on the walls as well as in the floor.
                              >> Kim
                              >>
                              >> William M. Bell, Jr. wrote:
                              >>
                              >>
                              >>> Robert:
                              >>>
                              >>> Thanks for the interest. I am not opposed to ammonia. It simply makes
                              >>
                              >> life a
                              >>
                              >>> little more complicated.
                              >>>
                              >>> I "designed" a system that used chilled water to cool and heated water
                              >>
                              >> to
                              >>
                              >>> heat. The main problem was that it required a rather large, insulated
                              >>> holding tank. I proposed to use a concrete tank and bury it.
                              >>>
                              >>> I found a simpler design that used silica gel and water. It uses
                              >>> solar-heated water to squeeze the water out of the silica gel. If you
                              >>
                              >> looked
                              >>
                              >>> at the web site that I listed, you can see a commercial application of
                              >>
                              >> such
                              >>
                              >>> a system. It has much going for it: few moving parts; no corrosive
                              >>> chemicals; no excessive pressures or temperatures; and simple. The only
                              >>> problem is that I can't find any residential applications and
                              >>
                              >> information is
                              >>
                              >>> scarce.
                              >>>
                              >>> Geothermal is cool, no pun intended. The main problem that I have
                              >>> encountered is that it is expensive to drill several wells and there is
                              >>
                              >> also
                              >>
                              >>> a fear that you could contaminate your drinking water. That is
                              >>
                              >> geothermal
                              >>
                              >>> that uses water wells. I have also heard of geothermal that circulated
                              >>
                              >> water
                              >>
                              >>> through pipes located 10+ feet below ground. A friend of mine worked
                              >>
                              >> with a
                              >>
                              >>> company that uses directional drilling to dig the lines for fiber optic
                              >>> cable and conduit. He thought that it would be an easy matter to use
                              >>
                              >> their
                              >>
                              >>> machine to drill the circulating lines. My biggest obstacle, is that I
                              >>
                              >> have
                              >>
                              >>> no idea how much line, etc that I would need. Lack of knowledge has
                              >>
                              >> stopped
                              >>
                              >>> me once again. My thought was that I could put a coil in my air
                              >>
                              >> conditioner
                              >>
                              >>> blower, before it got to the a/c coil, so that I could pre-cool my air.
                              >>
                              >> The
                              >>
                              >>> idea was that if it worked well enough, the a/c would not need to kick
                              >>
                              >> in. I
                              >>
                              >>> wanted to find a small circulating pump (again, I had no idea what size)
                              >>
                              >> and
                              >>
                              >>> have it run by a solar panel. The hotter it is outside, the more it
                              >>
                              >> pumps. I
                              >>
                              >>> have a friend in Lake Jackson who drilled several wells and used it to
                              >>
                              >> cool
                              >>
                              >>> his house. It worked OK for a while, but then he had problems with his
                              >>> wells.
                              >>>
                              >>> Anyway, I think that this is an interesting area and we would all
                              >>
                              >> benefit
                              >>
                              >>> from sharing our knowledge.
                              >>>
                              >>> ----- Original Message -----
                              >>> From: "Robert Johnston" <rjohnsto@...>
                              >>> To: <hreg@yahoogroups.com>
                              >>> Sent: Friday, August 31, 2001 6:14 PM
                              >>> Subject: [hreg] Solar Air Conditioners
                              >>>
                              >>>
                              >>>
                              >>>
                              >>>> Between the Nigerian Scams and the Environmental Spams, the good stuff
                              >>>
                              >> is
                              >>
                              >>>> hard to find here! However, there wasn't much comment on this note
                              >>>
                              >> from
                              >>
                              >>>> Billy Bell except Kevin pointing out the inefficiencies of
                              >>>
                              >> thermoelectric
                              >>
                              >>>> cooling (especially if tied to a solar cell!).
                              >>>>
                              >>>> However, it is an extremely interesting question and one I'd love to
                              >>>
                              >> see
                              >>
                              >>>> more discussion on. This is obviously one of the main barriers to this
                              >>>
                              >>> area
                              >>>
                              >>>
                              >>>> ever achieving the kind of renewable energy freedom that some other
                              >>>
                              >> parts
                              >>
                              >>> of
                              >>>
                              >>>
                              >>>> the country can do. The use of water as an evaporative coolant OK in
                              >>>> Arizona but not Houston--too humid already! In any case, even in a
                              >>>
                              >> closed
                              >>
                              >>>> system it wouldn't make a good medium for an efficient A/C.
                              >>>>
                              >>>> Anybody want to comment on what they think has the greatest potential
                              >>>
                              >> in
                              >>
                              >>> our
                              >>>
                              >>>
                              >>>> area?
                              >>>> Things that come to mind for me (besides ceiling fans, insulation,
                              >>>
                              >> etc.)
                              >>
                              >>>> are:
                              >>>>
                              >>>> 1. Dessicators. I know that natural gas fired units are now used for
                              >>>> commercial buildings in some locations. I don't know if any efficient
                              >>>
                              >>> solar
                              >>>
                              >>>
                              >>>> units have been designed. But if you could dry out the air, that would
                              >>>
                              >>> help
                              >>>
                              >>>
                              >>>> a lot. And then you might even be able to put a little cool water back
                              >>>
                              >> in
                              >>
                              >>>> as evaporative coolant as in Arizona.
                              >>>>
                              >>>> 2. Geothermal units. I'm puzzled why these haven't taken off, unless
                              >>>
                              >> it
                              >>
                              >>> is
                              >>>
                              >>>
                              >>>> their installation expense. Why are they so expensive? Are they not
                              >>>
                              >>> good?
                              >>>
                              >>>
                              >>>> A local A/C guy told me there are lots of problems with mold and odor
                              >>>
                              >> in
                              >>
                              >>> the
                              >>>
                              >>>
                              >>>> heat pump part of the installation. I don't know if that is true. He
                              >>>
                              >> is
                              >>
                              >>>> death on heat pumps **period** for that reason, and prefers straight
                              >>>
                              >>> A/C's.
                              >>>
                              >>>
                              >>>> But there is still something appealing to me of trying to cool
                              >>>
                              >> compressed
                              >>
                              >>>> gas with ground temperature rather than air temperature medium. I've
                              >>>
                              >> seen
                              >>
                              >>>> some of the numbers posted on the web (very high S.E.E.R.), but there
                              >>>
                              >> is a
                              >>
                              >>>> lot of hype by vendors. Since these aren't that popular, is it because
                              >>>
                              >>> they
                              >>>
                              >>>
                              >>>> don't work that well in practice, or is it just the cost of
                              >>>
                              >> installation?
                              >>
                              >>>> What is the payback period in this area, then? These are some
                              >>>
                              >> questions
                              >>
                              >>> I'd
                              >>>
                              >>>
                              >>>> like to see discussed.
                              >>>>
                              >>>> As far as ammonia goes, Billy--I know it is not nice stuff, but it used
                              >>>
                              >> to
                              >>
                              >>>> be used in refrigerators long ago, so with proper engineering I guess
                              >>>
                              >> it
                              >>
                              >>> was
                              >>>
                              >>>
                              >>>> managed OK. (Before my time, so I have no first hand experience). I
                              >>>
                              >> also
                              >>
                              >>>> know that TDC put some ammonia cooling systems on a couple of new
                              >>>
                              >> warden's
                              >>
                              >>>> homes at the prison farm south of Lake Jackson on the corner of
                              >>>> FM2004/FM2611 and State Hwy 36. It is a duplex unit. The houses have
                              >>>> optimally sloping roofs aimed towards the sun, and then on the rooftops
                              >>>
                              >>> were
                              >>>
                              >>>
                              >>>> solar collectors. They may have had solar hot water too--I don't
                              >>>> recall--but I remember reading in the newspaper when they built them
                              >>>
                              >> about
                              >>
                              >>>> their ammonia cooling systems. This would have been around 1981-85
                              >>>> timeframe. I also know that the collectors are now gone, but I don't
                              >>>
                              >> know
                              >>
                              >>>> why. It could just be that TDC didn't want to fuss with them--e.g., it
                              >>>
                              >>> may
                              >>>
                              >>>
                              >>>> have been environmentally "cool" (pun intended) to use solar on state
                              >>>> institutions at that time, but the maintenance expense for handling
                              >>>
                              >> such
                              >>
                              >>> an
                              >>>
                              >>>
                              >>>> unusual system that was different than all the other onsite A/C's might
                              >>>
                              >>> have
                              >>>
                              >>>
                              >>>> caused rethinking of the project down the road. Or, it may be that the
                              >>>> units just didn't hold up to use. I don't know, but I assume you could
                              >>>
                              >>> find
                              >>>
                              >>>
                              >>>> out more by asking around, or writing TDC.
                              >>>>
                              >>>> In any case, if any of you have some thoughts on the subject of solar
                              >>>
                              >> or
                              >>
                              >>>> just more efficient air conditioning/cooling, why don't we see if we
                              >>>
                              >> can
                              >>
                              >>> get
                              >>>
                              >>>
                              >>>> a discussion going on this subject and enlighten ourselves?
                              >>>>
                              >>>> Robert Johnston
                              >>>>
                              >>>> -----Original Message-----
                              >>>> From: William M. Bell, Jr. [mailto:wmb@...]
                              >>>> Sent: Wednesday, August 29, 2001 9:23 AM
                              >>>> To: hreg@yahoogroups.com
                              >>>> Subject: Re: [hreg] Digest Number 281
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>>> Wow! What an email regarding the livestock industry and the whales.
                              >>>>
                              >> Who
                              >>
                              >>>> are
                              >>>>
                              >>>>
                              >>>>> they from? tpwc---ENVIRO ALERT <envir_456@... doesn't do much
                              >>>>
                              >> for
                              >>
                              >>>> me.
                              >>>>
                              >>>>
                              >>>>> Steve Stelzer
                              >>>>
                              >>>> I thought that livestock produced methane, which was a renewable? Just
                              >>>> Kidding ; ) Although I appreciate information of this sort, I am more
                              >>>> concerned that this discussion group stays on target.
                              >>>>
                              >>>> By the way, I have been doing a great deal of looking around in my
                              >>>
                              >> spare
                              >>
                              >>>> time (which is not much) at solar air conditioners. There a number of
                              >>>> alternatives out there. It sounds strange until you view solar as an
                              >>>
                              >>> energy
                              >>>
                              >>>
                              >>>> source (heat). Most solar air conditioners work by a process called
                              >>>> adsorption. An efficient, economical solar a/c system, that could be
                              >>>
                              >> used
                              >>
                              >>> in
                              >>>
                              >>>
                              >>>> residential cooling would be an important contribution to renewable
                              >>>
                              >>> energy.
                              >>>
                              >>>
                              >>>> Think of the amount of heat generated in this city by a/c and the
                              >>>
                              >> amount
                              >>
                              >>> of
                              >>>
                              >>>
                              >>>> electricity that is wasted producing this heat.
                              >>>>
                              >>>> The adsorption units that I have looked at use either ammonia
                              >>>
                              >>> (refrigerant)
                              >>>
                              >>>
                              >>>> and calcium chloride (absorber) (or some other chemical) or water and
                              >>>
                              >>> silica
                              >>>
                              >>>
                              >>>> gel. The water and silica gel seems most promising to me. Ammonia is
                              >>>
                              >> too
                              >>
                              >>>> dangerous to have inside my house and it makes it difficult to work out
                              >>>
                              >> a
                              >>
                              >>>> system in which I can keep it outside. Water, however, is safe and when
                              >>>
                              >> it
                              >>
                              >>>> evaporates, absorbs a great deal of heat.
                              >>>>
                              >>>> There is also a solid state alternative that I have not had much
                              >>>
                              >>> opportunity
                              >>>
                              >>>
                              >>>> to explore. They use solid state refrigerators in small outdoor
                              >>>
                              >> coolers.
                              >>
                              >>>> When you pass a 12V current through the diode, one side gets hot and
                              >>>
                              >> the
                              >>
                              >>>> other side gets cool. Perhaps, we could use the hot side to pre-heat
                              >>>
                              >> our
                              >>
                              >>>> water to the hot water heater and the cold side to chill water that
                              >>>
                              >> could
                              >>
                              >>> be
                              >>>
                              >>>
                              >>>> used to cool the house, if needed. The unit could be attached to solar
                              >>>> panels that produce the 12V current. The hotter it is outside, the
                              >>>
                              >> harder
                              >>
                              >>>> the unit works. I like that!
                              >>>>
                              >>>> Some helpful web sites: http://www.caddet-ee.org/nl_html/001_02.htm
                              >>>> http://www.adsorptionchiller.com/
                              >>>>
                              >>>> Billy Bell
                              >>>> PO Box 926
                              >>>> Fulshear, Texas 77441-0926
                              >>>>
                              >>>> 713-439-1115 Telephone
                              >>>> 281-346-0994 Fax
                              >>>> wmb@...
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>> Your use of Yahoo! Groups is subject to
                              >>>
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                              >>
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>>
                              >>>> Your use of Yahoo! Groups is subject to
                              >>>
                              >> http://docs.yahoo.com/info/terms/
                              >>
                              >>>>
                              >>>
                              >>>
                              >>>
                              >>>
                              >>>
                              >>> Your use of Yahoo! Groups is subject to
                              >>
                              >> http://docs.yahoo.com/info/terms/
                              >>
                              >>
                              >>
                              >>
                              >>
                              >> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                              >>
                              >
                              >
                              >
                              >
                              >
                              > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                              >
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                              >
                              >
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                              > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                            • LaVerne Williams
                              Dear Kim & Garth & Robert Johnston: Robert: You have a good memory. I wish I could comment in detail but my current commitments are not leaving me much free
                              Message 14 of 28 , Sep 5, 2001
                                Dear Kim & Garth & Robert Johnston:
                                 
                                Robert:  You have a good memory.  I wish I could comment in detail but my current commitments are not leaving me much free time at all, but Kim is not talking about a "cool tube" concept, which would be a disaster health wise in probably most of Texas.  I think he is describing a system that is similar to a system being promoted from Dallas that has piping (metal. I think) that runs around a room with troughs below to catch the condensate to drain it.  I believe the McDermott Engineering building in West Houston used the system for a while but I believe they abandoned it.
                                 
                                Being only 100 miles from Houston, Kim & Garth, I wouldn't recommend such a system here or even in dessert areas.  They are having terrific mold problems in desert area homes.  I am not sure why because I am not currently working on any projects in such areas, but it may be a combination of tight homes and the use of "swamp type coolers".  Or it just may be tight homes with conventional HVAC systems and poor construction not having a drainage plane or oversized cooling systems.  Of course, compared to conditions that are set up to have mold growth in dessert areas means horrendous blossoming of mold growth in the humid Gulf Coast and Central Texas areas.
                                 
                                Anyway, mold will eventually form in the trough and if you could see what I am experiencing with people who have come to me because of very serious health problems they are having from mold in their houses, you would do everything possible to prevent mold from forming. (I'm working with a couple right now who decided to design and build their own house and now his wife has had around 17 strokes in her brain (MRI confirmed) primarily because of what mold  (and formaldehyde in common building materials)  can do.  They also have twins who are 5 years old who have only developed to that of 2 year olds, and one of them is not showing any signs of recovery.   I am helping them create a safe haven until we can do something more permanent for them).  I also have an Industrial Hygienist friend who is involved as an expert witness in over 1500 lawsuits because of mold growth and health problems with houses and buildings.  From what he has seen, the litigation concerning mold in buildings will dwarf what happened with asbestos in buildings
                                 
                                Hope this helps. 
                                 
                                To Everyone:  Molds kill.   Do everything you can to make your home mold free!!!  It is not something to take lightly.  Anytime and any place the relative humidity inside a home goes over 60% RH, mold grows!  (Aim for 50% RH or less year-round)  This woman was in such perfect health before they built their home 7 years ago that she worked out 2 hours a day!  Now she can barely care for herself and her twins.  They have had to abandon their house.
                                 
                                LaVerne A. Williams, AIA
                                laverne@...
                                Environment Associates, Architects & Consultants
                                5828 Langfield Road
                                Houston, TX 77092-1429
                                713.528.0000
                                 
                                 
                                 
                                 
                                ----- Original Message -----
                                From: "Kim & Garth Travis" <gartht@...>
                                Sent: Wednesday, September 05, 2001 8:22 AM
                                Subject: Re: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                > Hi,
                                >
                                >
                                 
                                >
                                >
                                > > I'm wondering what kind of cooling Kim has
                                in mind.
                                >
                                > I am using hydronics, an idea I got from Roth company
                                on the web.  PEX
                                > hose set in the floor and on the perimeter walls
                                at the 8' height.  Roth
                                > is using such systems commercially and has
                                an extensive web site.  At
                                > roth.com I think.
                                >
                                >
                                  In particular, I'm
                                > > wondering,
                                > > If you live in a
                                hot humid area,
                                >
                                > I live 100 miles north-northwest of
                                Houston.
                                >
                                > is ANY kind of cooling based on bringing
                                > >
                                cold air
                                > > or water into the house WITHOUT also having
                                dehumidificatio built into the
                                > > cooling
                                > > system setting
                                oneself up for mold, mildew and perhaps Legionnaire's
                                > >
                                Disease?  e.g.,
                                > > suppose you could use water pipes or any other
                                technology to cool the walls
                                > > and floor
                                > > of your home to
                                a pleasant 70?C and keep it there day and night. 
                                >
                                > We may
                                need to bring in a dehumidifier, but I like my home at 50%
                                >
                                humidity.  In Canada we used humidifiers to raise it this high.
                                >
                                Anything below this, we find uncomfortable.  I am sorry, but I do not
                                > find 70 degrees comfortable.  The joy of living in Texas is I
                                never need
                                > to be cool or cold again.  We are ranchers and work
                                outside, a
                                > temperature of 76 to 78 is comfortable to us.  Our
                                guest room has a
                                > separate control so company can sleep in cooler
                                temperatures.  [We are
                                > putting in a well screened sleeping porch
                                for most of the year]
                                >
                                > Our closets are 6" deeper than normal to
                                allow air circulation. We do
                                > not use wall to wall carpet, only area
                                rugs. The big trick is to have a
                                > super insulated building with wide
                                porches, good ventilation and never
                                > let it get hot. We first looked at
                                the historical buildings in Texas and
                                > how they kept them cool without
                                electricity.  Then we tried to design as
                                > many of those ideas as
                                possible into our buildings so our cooling
                                > demands are not those of a
                                normal tract home.
                                >
                                > The temperature difference between the
                                cooling and ambient temperatures
                                > can not be too great, [say over 15
                                degrees] or you have a real problem.
                                > The water we are using to cool is
                                65 degrees. The cool water comes in at
                                > the wall, where it has a drip
                                tray built under it, then circulates in
                                > the floor before
                                exiting.
                                >
                                > If we ever let it get hot in the building, we would
                                have to use some
                                > window units or something to cool the building or wait
                                a long time to
                                > gradually lower the temperature.  We have not built
                                our main house yet,
                                > we are working on our shops and installing all of
                                our ideas there, first.
                                >
                                >
                                >  (A vapor barrier would
                                be meaningless if you are not drying
                                > > the air
                                > >
                                inside).
                                >
                                > We do not use vapor barriers as our buildings are
                                fibrous adobe.
                                >
                                > >
                                > > LaVerne Williams, are you
                                reading this?  Did I summarize your comments
                                > >
                                accurately?
                                > > Would you care to comment on the futility of ANY
                                approaches to cooling a
                                > > house here
                                > > without
                                simultaneously providing dehumidification?  As long as the house
                                > > stays near
                                > > ambient temperature I would think things would be
                                OK, but the concern is
                                > > that you
                                > > might cool the house
                                below ambient in a humid environment.  Care to comment
                                > > on
                                what
                                > > appears to be Kim's plan to cool a building with cold water
                                pipes?
                                > >
                                > > Robert
                                > >
                                > >
                                -----Original Message-----
                                > > From: Claude Foster
                                [mailto:ccfoster@...]
                                > > Sent: Tuesday, September 04, 2001
                                7:51 AM
                                > > To:
                                size=2>'hreg@yahoogroups.com'
                                > > Subject: RE: [hreg] Solar Air Conditioners
                                > >
                                > >
                                > >
                                Kim,
                                > >
                                > > I will do some calculations for you if you will
                                contact me directly.
                                > >
                                > >
                                href="mailto:ccfoster@...">ccfoster@...
                                > >
                                > >
                                > >
                                > >
                                > >> -----Original Message-----
                                > >> From: Kim & Garth Travis [SMTP:gartht@...]
                                > >>
                                Sent: Saturday, September 01, 2001 7:16 AM
                                > >> To:
                                href="mailto:hreg@yahoogroups.com">hreg@yahoogroups.com
                                > >> Subject: Re: [hreg] Solar Air Conditioners
                                > >>
                                > >> Hi,
                                > >> I am planning using cooled water to cool a 1000 sq. ft. building. 
                                My
                                > >> circulating pump is from a 15' diameter swimming pool. 
                                I installed my
                                > >> pipe under a raised garden bed that is filled
                                with plants that like wet
                                > >> feet.  In the testing we have
                                done on the garden bed water, we seem to
                                > >> be washing the heat
                                away.  The plans call for the cooling pipe to be
                                > >> installed
                                at the 8' level on the walls as well as in the floor.
                                > >>
                                Kim
                                > >>
                                > >> William M. Bell, Jr. wrote:
                                > >>
                                > >>
                                > >>> Robert:
                                > >>>
                                > >>> Thanks for the interest. I am not opposed to ammonia. It
                                simply makes
                                > >>
                                > >> life a
                                > >>
                                > >>> little more complicated.
                                > >>>
                                > >>>
                                I "designed" a system that used chilled water to cool and heated water
                                > >>
                                > >> to
                                > >>
                                > >>> heat. The
                                main problem was that it required a rather large, insulated
                                > >>>
                                holding tank. I proposed to use a concrete tank and bury it.
                                > >>>
                                > >>> I found a simpler design that used silica gel
                                and water. It uses
                                > >>> solar-heated water to squeeze the water
                                out of the silica gel. If you
                                > >>
                                > >> looked
                                > >>
                                > >>> at the web site that I listed, you can see a
                                commercial application of
                                > >>
                                > >> such
                                > >>
                                > >>> a system. It has much going for it: few moving
                                parts; no corrosive
                                > >>> chemicals; no excessive pressures or
                                temperatures; and simple. The only
                                > >>> problem is that I can't
                                find any residential applications and
                                > >>
                                > >>
                                information is
                                > >>
                                > >>> scarce.
                                > >>>
                                > >>> Geothermal is cool, no pun intended. The main
                                problem that I have
                                > >>> encountered is that it is expensive to
                                drill several wells and there is
                                > >>
                                > >> also
                                > >>
                                > >>> a fear that you could contaminate your drinking
                                water. That is
                                > >>
                                > >> geothermal
                                > >>
                                > >>> that uses water wells. I have also heard of geothermal
                                that circulated
                                > >>
                                > >> water
                                > >>
                                > >>> through pipes located 10+ feet below ground. A friend of
                                mine worked
                                > >>
                                > >> with a
                                > >>
                                > >>> company that uses directional drilling to dig the lines for fiber
                                optic
                                > >>> cable and conduit. He thought that it would be an
                                easy matter to use
                                > >>
                                > >> their
                                > >>
                                > >>> machine to drill the circulating lines. My biggest
                                obstacle, is that I
                                > >>
                                > >> have
                                > >>
                                > >>> no idea how much line, etc that I would need. Lack of
                                knowledge has
                                > >>
                                > >> stopped
                                > >>
                                > >>> me once again. My thought was that I could put a coil in
                                my air
                                > >>
                                > >> conditioner
                                > >>
                                > >>> blower, before it got to the a/c coil, so that I could pre-cool my
                                air.
                                > >>
                                > >> The
                                > >>
                                > >>> idea was that if it worked well enough, the a/c would not need to
                                kick
                                > >>
                                > >> in. I
                                > >>
                                > >>> wanted to find a small circulating pump (again, I had no idea what
                                size)
                                > >>
                                > >> and
                                > >>
                                > >>> have it run by a solar panel. The hotter it is outside, the more
                                it
                                > >>
                                > >> pumps. I
                                > >>
                                > >>> have a friend in Lake Jackson who drilled several wells and used it
                                to
                                > >>
                                > >> cool
                                > >>
                                > >>> his house. It worked OK for a while, but then he had problems with
                                his
                                > >>> wells.
                                > >>>
                                > >>>
                                Anyway, I think that this is an interesting area and we would all
                                > >>
                                > >> benefit
                                > >>
                                > >>> from
                                sharing our knowledge.
                                > >>>
                                > >>> ----- Original
                                Message -----
                                > >>> From: "Robert Johnston" <
                                href="mailto:rjohnsto@...">rjohnsto@...>
                                > >>> To: <
                                size=2>hreg@yahoogroups.com>
                                > >>>
                                Sent: Friday, August 31, 2001 6:14 PM
                                > >>> Subject: [hreg] Solar
                                Air Conditioners
                                > >>>
                                > >>>
                                > >>>
                                > >>>
                                > >>>> Between the
                                Nigerian Scams and the Environmental Spams, the good stuff
                                > >>>
                                > >> is
                                > >>
                                > >>>> hard to find
                                here!  However, there wasn't much comment on this note
                                > >>>
                                > >> from
                                > >>
                                > >>>> Billy Bell
                                except Kevin pointing out the inefficiencies of
                                > >>>
                                > >> thermoelectric
                                > >>
                                > >>>> cooling
                                (especially if tied to a solar cell!).
                                > >>>>
                                > >>>> However, it is an extremely interesting question and one I'd
                                love to
                                > >>>
                                > >> see
                                > >>
                                > >>>> more discussion on.  This is obviously one of the main
                                barriers to this
                                > >>>
                                > >>> area
                                > >>>
                                > >>>
                                > >>>> ever achieving the
                                kind of renewable energy freedom that some other
                                > >>>
                                > >> parts
                                > >>
                                > >>> of
                                > >>>
                                > >>>
                                > >>>> the country can do.  The
                                use of water as an evaporative coolant OK in
                                > >>>> Arizona
                                but not Houston--too humid already!  In any case, even in a
                                > >>>
                                > >> closed
                                > >>
                                > >>>>
                                system it wouldn't make a good medium for an efficient A/C.
                                > >>>>
                                > >>>> Anybody want to comment on what they
                                think has the greatest potential
                                > >>>
                                > >>
                                in
                                > >>
                                > >>> our
                                > >>>
                                > >>>
                                > >>>> area?
                                > >>>> Things
                                that come to mind for me (besides ceiling fans, insulation,
                                > >>>
                                > >> etc.)
                                > >>
                                > >>>> are:
                                > >>>>
                                > >>>> 1.  Dessicators.  I know
                                that natural gas fired units are now used for
                                > >>>>
                                commercial buildings in some locations.  I don't know if any efficient
                                > >>>
                                > >>> solar
                                > >>>
                                > >>>
                                > >>>> units have been designed. 
                                But if you could dry out the air, that would
                                > >>>
                                > >>> help
                                > >>>
                                > >>>
                                > >>>> a lot.  And then you might even be able to put a little
                                cool water back
                                > >>>
                                > >> in
                                > >>
                                > >>>> as evaporative coolant as in Arizona.
                                > >>>>
                                > >>>> 2.  Geothermal units.  I'm
                                puzzled why these haven't taken off, unless
                                > >>>
                                > >> it
                                > >>
                                > >>> is
                                > >>>
                                > >>>
                                > >>>> their installation
                                expense.  Why are they so expensive?  Are they not
                                > >>>
                                > >>> good?
                                > >>>
                                > >>>
                                > >>>> A local A/C guy told me there are lots of
                                problems with mold and odor
                                > >>>
                                > >> in
                                > >>
                                > >>> the
                                > >>>
                                > >>>
                                > >>>> heat pump part of the installation.  I don't know
                                if that is true.  He
                                > >>>
                                > >> is
                                > >>
                                > >>>> death on heat pumps **period** for that
                                reason, and prefers straight
                                > >>>
                                > >>>
                                A/C's.
                                > >>>
                                > >>>
                                > >>>> But
                                there is still something appealing to me of trying to cool
                                > >>>
                                > >> compressed
                                > >>
                                > >>>> gas with
                                ground temperature rather than air temperature medium.  I've
                                > >>>
                                > >> seen
                                > >>
                                > >>>>
                                some of the numbers posted on the web (very high S.E.E.R.), but there
                                > >>>
                                > >> is a
                                > >>
                                > >>>>
                                lot of hype by vendors.  Since these aren't that popular, is it because
                                > >>>
                                > >>> they
                                > >>>
                                > >>>
                                > >>>> don't work that well in
                                practice, or is it just the cost of
                                > >>>
                                > >>
                                installation?
                                > >>
                                > >>>> What is the payback
                                period in this area, then?  These are some
                                > >>>
                                > >> questions
                                > >>
                                > >>> I'd
                                > >>>
                                > >>>
                                > >>>> like to see
                                discussed.
                                > >>>>
                                > >>>> As far as ammonia
                                goes, Billy--I know it is not nice stuff, but it used
                                > >>>
                                > >> to
                                > >>
                                > >>>> be used in
                                refrigerators long ago, so with proper engineering I guess
                                > >>>
                                > >> it
                                > >>
                                > >>> was
                                > >>>
                                > >>>
                                > >>>> managed OK. 
                                (Before my time, so I have no first hand experience).  I
                                > >>>
                                > >> also
                                > >>
                                > >>>>
                                know that TDC put some ammonia cooling systems on a couple of new
                                > >>>
                                > >> warden's
                                > >>
                                > >>>> homes at the prison farm south of Lake Jackson on the corner
                                of
                                > >>>> FM2004/FM2611 and State Hwy 36.  It is a duplex
                                unit.  The houses have
                                > >>>> optimally sloping roofs
                                aimed towards the sun, and then on the rooftops
                                > >>>
                                > >>> were
                                > >>>
                                > >>>
                                > >>>> solar collectors.  They may have had solar hot water
                                too--I don't
                                > >>>> recall--but I remember reading in the
                                newspaper when they built them
                                > >>>
                                > >>
                                about
                                > >>
                                > >>>> their ammonia cooling
                                systems.  This would have been around 1981-85
                                > >>>>
                                timeframe.  I also know that the collectors are now gone, but I don't
                                > >>>
                                > >> know
                                > >>
                                > >>>> why.  It could just be that TDC didn't want to fuss with
                                them--e.g., it
                                > >>>
                                > >>> may
                                > >>>
                                > >>>
                                > >>>> have been
                                environmentally "cool" (pun intended) to use solar on state
                                > >>>> institutions at that time, but the maintenance expense for
                                handling
                                > >>>
                                > >> such
                                > >>
                                > >>> an
                                > >>>
                                > >>>
                                > >>>> unusual system that was different than all the other onsite
                                A/C's might
                                > >>>
                                > >>> have
                                > >>>
                                > >>>
                                > >>>> caused rethinking of the project
                                down the road.  Or, it may be that the
                                > >>>> units just
                                didn't hold up to use.  I don't know, but I assume you could
                                > >>>
                                > >>> find
                                > >>>
                                > >>>
                                > >>>> out more by asking around, or writing
                                TDC.
                                > >>>>
                                > >>>> In any case, if any of
                                you have some thoughts on the subject of solar
                                > >>>
                                > >> or
                                > >>
                                > >>>> just more efficient air
                                conditioning/cooling, why don't we see if we
                                > >>>
                                > >> can
                                > >>
                                > >>> get
                                > >>>
                                > >>>
                                > >>>> a discussion going on this
                                subject and enlighten ourselves?
                                > >>>>
                                > >>>> Robert Johnston
                                > >>>>
                                > >>>> -----Original Message-----
                                > >>>> From:
                                William M. Bell, Jr. [mailto:wmb@...]
                                > >>>> Sent:
                                Wednesday, August 29, 2001 9:23 AM
                                > >>>> To:
                                href="mailto:hreg@yahoogroups.com">hreg@yahoogroups.com
                                > >>>> Subject: Re: [hreg] Digest Number 281
                                > >>>>
                                > >>>>
                                > >>>>
                                > >>>>
                                > >>>>> Wow! What an email regarding the livestock industry and the
                                whales.
                                > >>>>
                                > >> Who
                                > >>
                                > >>>> are
                                > >>>>
                                > >>>>
                                > >>>>> they from?  tpwc---ENVIRO ALERT <
                                href="mailto:envir_456@...">envir_456@... doesn't do much
                                > >>>>
                                > >> for
                                > >>
                                > >>>> me.
                                > >>>>
                                > >>>>
                                > >>>>> Steve Stelzer
                                > >>>>
                                > >>>> I thought that livestock produced methane, which was a
                                renewable? Just
                                > >>>> Kidding  ; )  Although I
                                appreciate information of this sort, I am more
                                > >>>>
                                concerned that this discussion group stays on target.
                                > >>>>
                                > >>>> By the way, I have been doing a great deal of looking
                                around in my
                                > >>>
                                > >> spare
                                > >>
                                > >>>> time (which is not much) at solar air conditioners.
                                There a number of
                                > >>>> alternatives out there. It sounds
                                strange until you view solar as an
                                > >>>
                                > >>>
                                energy
                                > >>>
                                > >>>
                                > >>>>
                                source (heat). Most solar air conditioners work by a process called
                                > >>>> adsorption. An efficient, economical solar a/c system, that
                                could be
                                > >>>
                                > >> used
                                > >>
                                > >>> in
                                > >>>
                                > >>>
                                > >>>> residential cooling would be an important contribution to
                                renewable
                                > >>>
                                > >>> energy.
                                > >>>
                                > >>>
                                > >>>> Think of the amount
                                of heat generated in this city by a/c and the
                                > >>>
                                > >> amount
                                > >>
                                > >>> of
                                > >>>
                                > >>>
                                > >>>> electricity that is wasted
                                producing this heat.
                                > >>>>
                                > >>>> The
                                adsorption units that I have looked at use either ammonia
                                > >>>
                                > >>> (refrigerant)
                                > >>>
                                > >>>
                                > >>>> and calcium chloride (absorber) (or some other
                                chemical) or water and
                                > >>>
                                > >>> silica
                                > >>>
                                > >>>
                                > >>>> gel. The water and
                                silica gel seems most promising to me. Ammonia is
                                > >>>
                                > >> too
                                > >>
                                > >>>> dangerous to have inside
                                my house and it makes it difficult to work out
                                > >>>
                                > >> a
                                > >>
                                > >>>> system in which I can keep
                                it outside. Water, however, is safe and when
                                > >>>
                                > >> it
                                > >>
                                > >>>> evaporates, absorbs a
                                great deal of heat.
                                > >>>>
                                > >>>> There is
                                also a solid state alternative that I have not had much
                                > >>>
                                > >>> opportunity
                                > >>>
                                > >>>
                                > >>>> to explore. They use solid state refrigerators in
                                small outdoor
                                > >>>
                                > >> coolers.
                                > >>
                                > >>>> When you pass a 12V current through the diode, one
                                side gets hot and
                                > >>>
                                > >> the
                                > >>
                                > >>>> other side gets cool. Perhaps, we could use the hot
                                side to pre-heat
                                > >>>
                                > >> our
                                > >>
                                > >>>> water to the hot water heater and the cold side to
                                chill water that
                                > >>>
                                > >> could
                                > >>
                                > >>> be
                                > >>>
                                > >>>
                                > >>>> used to cool the house, if needed. The unit could be attached
                                to solar
                                > >>>> panels that produce the 12V current. The
                                hotter it is outside, the
                                > >>>
                                > >> harder
                                > >>
                                > >>>> the unit works. I like that!
                                > >>>>
                                > >>>> Some helpful web sites:
                                href="http://www.caddet-ee.org/nl_html/001_02.htm">http://www.caddet-ee.org/nl_html/001_02.htm
                                > >>>> http://www.adsorptionchiller.com/
                                >
                                >>>>
                                > >>>> Billy Bell
                                > >>>>
                                PO Box 926
                                > >>>> Fulshear, Texas 77441-0926
                                > >>>>
                                > >>>> 713-439-1115 Telephone
                                > >>>> 281-346-0994 Fax
                                > >>>>
                                href="mailto:wmb@...">wmb@...
                                > >>>>
                                > >>>>
                                > >>>>
                                > >>>>
                                > >>>>
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                                > >>>
                                > >>
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                                >>
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                                > >>>
                                > >>
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                                >>
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                                > >>>
                                > >>>
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                                > >>>
                                > >>> Your use of Yahoo! Groups is subject to
                                > >>
                                > >>
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                              • Robert Johnston
                                Thanks Laverne for the clarification. I just remember that your comments were sufficiently sobering that I started looking for other avenues. Your new
                                Message 15 of 28 , Sep 5, 2001
                                  Thanks Laverne for the clarification.  I just remember that your comments were sufficiently sobering that
                                  I started looking for other avenues.  Your new comments only add to those concerns.  I think you are
                                  right about the mold and mildew liabilities.  It may be tougher for the class action lawyers since there isn't
                                  a single deep pocketed company like Johns Mansville, but I imagine there are enough major builders like
                                  U.S. Homes etc. that they can find enough targets to keep them in BMW's for a few years at least.
                                   
                                  Robert
                                  -----Original Message-----
                                  From: LaVerne Williams [mailto:wa@...]
                                  Sent: Wednesday, September 05, 2001 1:05 PM
                                  To: hreg@yahoogroups.com
                                  Subject: Re: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                  Dear Kim & Garth & Robert Johnston:
                                   
                                  Robert:  You have a good memory.  I wish I could comment in detail but my current commitments are not leaving me much free time at all, but Kim is not talking about a "cool tube" concept, which would be a disaster health wise in probably most of Texas.  I think he is describing a system that is similar to a system being promoted from Dallas that has piping (metal. I think) that runs around a room with troughs below to catch the condensate to drain it.  I believe the McDermott Engineering building in West Houston used the system for a while but I believe they abandoned it.
                                   
                                  Being only 100 miles from Houston, Kim & Garth, I wouldn't recommend such a system here or even in dessert areas.  They are having terrific mold problems in desert area homes.  I am not sure why because I am not currently working on any projects in such areas, but it may be a combination of tight homes and the use of "swamp type coolers".  Or it just may be tight homes with conventional HVAC systems and poor construction not having a drainage plane or oversized cooling systems.  Of course, compared to conditions that are set up to have mold growth in dessert areas means horrendous blossoming of mold growth in the humid Gulf Coast and Central Texas areas.
                                   
                                  Anyway, mold will eventually form in the trough and if you could see what I am experiencing with people who have come to me because of very serious health problems they are having from mold in their houses, you would do everything possible to prevent mold from forming. (I'm working with a couple right now who decided to design and build their own house and now his wife has had around 17 strokes in her brain (MRI confirmed) primarily because of what mold  (and formaldehyde in common building materials)  can do.  They also have twins who are 5 years old who have only developed to that of 2 year olds, and one of them is not showing any signs of recovery.   I am helping them create a safe haven until we can do something more permanent for them).  I also have an Industrial Hygienist friend who is involved as an expert witness in over 1500 lawsuits because of mold growth and health problems with houses and buildings.  From what he has seen, the litigation concerning mold in buildings will dwarf what happened with asbestos in buildings
                                   
                                  Hope this helps. 
                                   
                                  To Everyone:  Molds kill.   Do everything you can to make your home mold free!!!  It is not something to take lightly.  Anytime and any place the relative humidity inside a home goes over 60% RH, mold grows!  (Aim for 50% RH or less year-round)  This woman was in such perfect health before they built their home 7 years ago that she worked out 2 hours a day!  Now she can barely care for herself and her twins.  They have had to abandon their house.
                                   
                                  LaVerne A. Williams, AIA
                                  laverne@...
                                  Environment Associates, Architects & Consultants
                                  5828 Langfield Road
                                  Houston, TX 77092-1429
                                  713.528.0000
                                   
                                   
                                   
                                   
                                  ----- Original Message -----
                                  From: "Kim & Garth Travis" <gartht@...>
                                  Sent: Wednesday, September 05, 2001 8:22 AM
                                  Subject: Re: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                  > Hi,
                                  >
                                  >  
                                  >
                                  >
                                  > > I'm wondering what kind of cooling Kim has in mind.
                                  >
                                  > I am using hydronics, an idea I got from Roth company on the web.  PEX
                                  > hose set in the floor and on the perimeter walls at the 8' height.  Roth
                                  > is using such systems commercially and has an extensive web site.  At
                                  > roth.com I think.
                                  >
                                  >   In particular, I'm
                                  > > wondering,
                                  > > If you live in a hot humid area,
                                  >
                                  > I live 100 miles north-northwest of Houston.
                                  >
                                  > is ANY kind of cooling based on bringing
                                  > > cold air
                                  > > or water into the house WITHOUT also having dehumidificatio built into the
                                  > > cooling
                                  > > system setting oneself up for mold, mildew and perhaps Legionnaire's
                                  > > Disease?  e.g.,
                                  > > suppose you could use water pipes or any other technology to cool the walls
                                  > > and floor
                                  > > of your home to a pleasant 70?C and keep it there day and night. 
                                  >
                                  > We may need to bring in a dehumidifier, but I like my home at 50%
                                  > humidity.  In Canada we used humidifiers to raise it this high.
                                  > Anything below this, we find uncomfortable.  I am sorry, but I do not
                                  > find 70 degrees comfortable.  The joy of living in Texas is I never need
                                  > to be cool or cold again.  We are ranchers and work outside, a
                                  > temperature of 76 to 78 is comfortable to us.  Our guest room has a
                                  > separate control so company can sleep in cooler temperatures.  [We are
                                  > putting in a well screened sleeping porch for most of the year]
                                  >
                                  > Our closets are 6" deeper than normal to allow air circulation. We do
                                  > not use wall to wall carpet, only area rugs. The big trick is to have a
                                  > super insulated building with wide porches, good ventilation and never
                                  > let it get hot. We first looked at the historical buildings in Texas and
                                  > how they kept them cool without electricity.  Then we tried to design as
                                  > many of those ideas as possible into our buildings so our cooling
                                  > demands are not those of a normal tract home.
                                  >
                                  > The temperature difference between the cooling and ambient temperatures
                                  > can not be too great, [say over 15 degrees] or you have a real problem.
                                  > The water we are using to cool is 65 degrees. The cool water comes in at
                                  > the wall, where it has a drip tray built under it, then circulates in
                                  > the floor before exiting.
                                  >
                                  > If we ever let it get hot in the building, we would have to use some
                                  > window units or something to cool the building or wait a long time to
                                  > gradually lower the temperature.  We have not built our main house yet,
                                  > we are working on our shops and installing all of our ideas there, first.
                                  >
                                  >
                                  >  (A vapor barrier would be meaningless if you are not drying
                                  > > the air
                                  > > inside).
                                  >
                                  > We do not use vapor barriers as our buildings are fibrous adobe.
                                  >
                                  > >
                                  > > LaVerne Williams, are you reading this?  Did I summarize your comments
                                  > > accurately?
                                  > > Would you care to comment on the futility of ANY approaches to cooling a
                                  > > house here
                                  > > without simultaneously providing dehumidification?  As long as the house
                                  > > stays near
                                  > > ambient temperature I would think things would be OK, but the concern is
                                  > > that you
                                  > > might cool the house below ambient in a humid environment.  Care to comment
                                  > > on what
                                  > > appears to be Kim's plan to cool a building with cold water pipes?
                                  > >
                                  > > Robert
                                  > >
                                  > > -----Original Message-----
                                  > > From: Claude Foster [mailto:ccfoster@...]
                                  > > Sent: Tuesday, September 04, 2001 7:51 AM
                                  > > To:
                                  'hreg@yahoogroups.com'
                                  > > Subject: RE: [hreg] Solar Air Conditioners
                                  > >
                                  > >
                                  > > Kim,
                                  > >
                                  > > I will do some calculations for you if you will contact me directly.
                                  > >
                                  > >
                                  ccfoster@...
                                  > >
                                  > >
                                  > >
                                  > >
                                  > >> -----Original Message-----
                                  > >> From: Kim & Garth Travis [SMTP:gartht@...]
                                  > >> Sent: Saturday, September 01, 2001 7:16 AM
                                  > >> To:
                                  hreg@yahoogroups.com
                                  > >> Subject: Re: [hreg] Solar Air Conditioners
                                  > >>
                                  > >> Hi,
                                  > >> I am planning using cooled water to cool a 1000 sq. ft. building.  My
                                  > >> circulating pump is from a 15' diameter swimming pool.  I installed my
                                  > >> pipe under a raised garden bed that is filled with plants that like wet
                                  > >> feet.  In the testing we have done on the garden bed water, we seem to
                                  > >> be washing the heat away.  The plans call for the cooling pipe to be
                                  > >> installed at the 8' level on the walls as well as in the floor.
                                  > >> Kim
                                  > >>
                                  > >> William M. Bell, Jr. wrote:
                                  > >>
                                  > >>
                                  > >>> Robert:
                                  > >>>
                                  > >>> Thanks for the interest. I am not opposed to ammonia. It simply makes
                                  > >>
                                  > >> life a
                                  > >>
                                  > >>> little more complicated.
                                  > >>>
                                  > >>> I "designed" a system that used chilled water to cool and heated water
                                  > >>
                                  > >> to
                                  > >>
                                  > >>> heat. The main problem was that it required a rather large, insulated
                                  > >>> holding tank. I proposed to use a concrete tank and bury it.
                                  > >>>
                                  > >>> I found a simpler design that used silica gel and water. It uses
                                  > >>> solar-heated water to squeeze the water out of the silica gel. If you
                                  > >>
                                  > >> looked
                                  > >>
                                  > >>> at the web site that I listed, you can see a commercial application of
                                  > >>
                                  > >> such
                                  > >>
                                  > >>> a system. It has much going for it: few moving parts; no corrosive
                                  > >>> chemicals; no excessive pressures or temperatures; and simple. The only
                                  > >>> problem is that I can't find any residential applications and
                                  > >>
                                  > >> information is
                                  > >>
                                  > >>> scarce.
                                  > >>>
                                  > >>> Geothermal is cool, no pun intended. The main problem that I have
                                  > >>> encountered is that it is expensive to drill several wells and there is
                                  > >>
                                  > >> also
                                  > >>
                                  > >>> a fear that you could contaminate your drinking water. That is
                                  > >>
                                  > >> geothermal
                                  > >>
                                  > >>> that uses water wells. I have also heard of geothermal that circulated
                                  > >>
                                  > >> water
                                  > >>
                                  > >>> through pipes located 10+ feet below ground. A friend of mine worked
                                  > >>
                                  > >> with a
                                  > >>
                                  > >>> company that uses directional drilling to dig the lines for fiber optic
                                  > >>> cable and conduit. He thought that it would be an easy matter to use
                                  > >>
                                  > >> their
                                  > >>
                                  > >>> machine to drill the circulating lines. My biggest obstacle, is that I
                                  > >>
                                  > >> have
                                  > >>
                                  > >>> no idea how much line, etc that I would need. Lack of knowledge has
                                  > >>
                                  > >> stopped
                                  > >>
                                  > >>> me once again. My thought was that I could put a coil in my air
                                  > >>
                                  > >> conditioner
                                  > >>
                                  > >>> blower, before it got to the a/c coil, so that I could pre-cool my air.
                                  > >>
                                  > >> The
                                  > >>
                                  > >>> idea was that if it worked well enough, the a/c would not need to kick
                                  > >>
                                  > >> in. I
                                  > >>
                                  > >>> wanted to find a small circulating pump (again, I had no idea what size)
                                  > >>
                                  > >> and
                                  > >>
                                  > >>> have it run by a solar panel. The hotter it is outside, the more it
                                  > >>
                                  > >> pumps. I
                                  > >>
                                  > >>> have a friend in Lake Jackson who drilled several wells and used it to
                                  > >>
                                  > >> cool
                                  > >>
                                  > >>> his house. It worked OK for a while, but then he had problems with his
                                  > >>> wells.
                                  > >>>
                                  > >>> Anyway, I think that this is an interesting area and we would all
                                  > >>
                                  > >> benefit
                                  > >>
                                  > >>> from sharing our knowledge.
                                  > >>>
                                  > >>> ----- Original Message -----
                                  > >>> From: "Robert Johnston" <
                                  rjohnsto@...>
                                  > >>> To: <
                                  hreg@yahoogroups.com>
                                  > >>> Sent: Friday, August 31, 2001 6:14 PM
                                  > >>> Subject: [hreg] Solar Air Conditioners
                                  > >>>
                                  > >>>
                                  > >>>
                                  > >>>
                                  > >>>> Between the Nigerian Scams and the Environmental Spams, the good stuff
                                  > >>>
                                  > >> is
                                  > >>
                                  > >>>> hard to find here!  However, there wasn't much comment on this note
                                  > >>>
                                  > >> from
                                  > >>
                                  > >>>> Billy Bell except Kevin pointing out the inefficiencies of
                                  > >>>
                                  > >> thermoelectric
                                  > >>
                                  > >>>> cooling (especially if tied to a solar cell!).
                                  > >>>>
                                  > >>>> However, it is an extremely interesting question and one I'd love to
                                  > >>>
                                  > >> see
                                  > >>
                                  > >>>> more discussion on.  This is obviously one of the main barriers to this
                                  > >>>
                                  > >>> area
                                  > >>>
                                  > >>>
                                  > >>>> ever achieving the kind of renewable energy freedom that some other
                                  > >>>
                                  > >> parts
                                  > >>
                                  > >>> of
                                  > >>>
                                  > >>>
                                  > >>>> the country can do.  The use of water as an evaporative coolant OK in
                                  > >>>> Arizona but not Houston--too humid already!  In any case, even in a
                                  > >>>
                                  > >> closed
                                  > >>
                                  > >>>> system it wouldn't make a good medium for an efficient A/C.
                                  > >>>>
                                  > >>>> Anybody want to comment on what they think has the greatest potential
                                  > >>>
                                  > >> in
                                  > >>
                                  > >>> our
                                  > >>>
                                  > >>>
                                  > >>>> area?
                                  > >>>> Things that come to mind for me (besides ceiling fans, insulation,
                                  > >>>
                                  > >> etc.)
                                  > >>
                                  > >>>> are:
                                  > >>>>
                                  > >>>> 1.  Dessicators.  I know that natural gas fired units are now used for
                                  > >>>> commercial buildings in some locations.  I don't know if any efficient
                                  > >>>
                                  > >>> solar
                                  > >>>
                                  > >>>
                                  > >>>> units have been designed.  But if you could dry out the air, that would
                                  > >>>
                                  > >>> help
                                  > >>>
                                  > >>>
                                  > >>>> a lot.  And then you might even be able to put a little cool water back
                                  > >>>
                                  > >> in
                                  > >>
                                  > >>>> as evaporative coolant as in Arizona.
                                  > >>>>
                                  > >>>> 2.  Geothermal units.  I'm puzzled why these haven't taken off, unless
                                  > >>>
                                  > >> it
                                  > >>
                                  > >>> is
                                  > >>>
                                  > >>>
                                  > >>>> their installation expense.  Why are they so expensive?  Are they not
                                  > >>>
                                  > >>> good?
                                  > >>>
                                  > >>>
                                  > >>>> A local A/C guy told me there are lots of problems with mold and odor
                                  > >>>
                                  > >> in
                                  > >>
                                  > >>> the
                                  > >>>
                                  > >>>
                                  > >>>> heat pump part of the installation.  I don't know if that is true.  He
                                  > >>>
                                  > >> is
                                  > >>
                                  > >>>> death on heat pumps **period** for that reason, and prefers straight
                                  > >>>
                                  > >>> A/C's.
                                  > >>>
                                  > >>>
                                  > >>>> But there is still something appealing to me of trying to cool
                                  > >>>
                                  > >> compressed
                                  > >>
                                  > >>>> gas with ground temperature rather than air temperature medium.  I've
                                  > >>>
                                  > >> seen
                                  > >>
                                  > >>>> some of the numbers posted on the web (very high S.E.E.R.), but there
                                  > >>>
                                  > >> is a
                                  > >>
                                  > >>>> lot of hype by vendors.  Since these aren't that popular, is it because
                                  > >>>
                                  > >>> they
                                  > >>>
                                  > >>>
                                  > >>>> don't work that well in practice, or is it just the cost of
                                  > >>>
                                  > >> installation?
                                  > >>
                                  > >>>> What is the payback period in this area, then?  These are some
                                  > >>>
                                  > >> questions
                                  > >>
                                  > >>> I'd
                                  > >>>
                                  > >>>
                                  > >>>> like to see discussed.
                                  > >>>>
                                  > >>>> As far as ammonia goes, Billy--I know it is not nice stuff, but it used
                                  > >>>
                                  > >> to
                                  > >>
                                  > >>>> be used in refrigerators long ago, so with proper engineering I guess
                                  > >>>
                                  > >> it
                                  > >>
                                  > >>> was
                                  > >>>
                                  > >>>
                                  > >>>> managed OK.  (Before my time, so I have no first hand experience).  I
                                  > >>>
                                  > >> also
                                  > >>
                                  > >>>> know that TDC put some ammonia cooling systems on a couple of new
                                  > >>>
                                  > >> warden's
                                  > >>
                                  > >>>> homes at the prison farm south of Lake Jackson on the corner of
                                  > >>>> FM2004/FM2611 and State Hwy 36.  It is a duplex unit.  The houses have
                                  > >>>> optimally sloping roofs aimed towards the sun, and then on the rooftops
                                  > >>>
                                  > >>> were
                                  > >>>
                                  > >>>
                                  > >>>> solar collectors.  They may have had solar hot water too--I don't
                                  > >>>> recall--but I remember reading in the newspaper when they built them
                                  > >>>
                                  > >> about
                                  > >>
                                  > >>>> their ammonia cooling systems.  This would have been around 1981-85
                                  > >>>> timeframe.  I also know that the collectors are now gone, but I don't
                                  > >>>
                                  > >> know
                                  > >>
                                  > >>>> why.  It could just be that TDC didn't want to fuss with them--e.g., it
                                  > >>>
                                  > >>> may
                                  > >>>
                                  > >>>
                                  > >>>> have been environmentally "cool" (pun intended) to use solar on state
                                  > >>>> institutions at that time, but the maintenance expense for handling
                                  > >>>
                                  > >> such
                                  > >>
                                  > >>> an
                                  > >>>
                                  > >>>
                                  > >>>> unusual system that was different than all the other onsite A/C's might
                                  > >>>
                                  > >>> have
                                  > >>>
                                  > >>>
                                  > >>>> caused rethinking of the project down the road.  Or, it may be that the
                                  > >>>> units just didn't hold up to use.  I don't know, but I assume you could
                                  > >>>
                                  > >>> find
                                  > >>>
                                  > >>>
                                  > >>>> out more by asking around, or writing TDC.
                                  > >>>>
                                  > >>>> In any case, if any of you have some thoughts on the subject of solar
                                  > >>>
                                  > >> or
                                  > >>
                                  > >>>> just more efficient air conditioning/cooling, why don't we see if we
                                  > >>>
                                  > >> can
                                  > >>
                                  > >>> get
                                  > >>>
                                  > >>>
                                  > >>>> a discussion going on this subject and enlighten ourselves?
                                  > >>>>
                                  > >>>> Robert Johnston
                                  > >>>>
                                  > >>>> -----Original Message-----
                                  > >>>> From: William M. Bell, Jr. [mailto:wmb@...]
                                  > >>>> Sent: Wednesday, August 29, 2001 9:23 AM
                                  > >>>> To:
                                  hreg@yahoogroups.com
                                  > >>>> Subject: Re: [hreg] Digest Number 281
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>> Wow! What an email regarding the livestock industry and the whales.
                                  > >>>>
                                  > >> Who
                                  > >>
                                  > >>>> are
                                  > >>>>
                                  > >>>>
                                  > >>>>> they from?  tpwc---ENVIRO ALERT <
                                  envir_456@... doesn't do much
                                  > >>>>
                                  > >> for
                                  > >>
                                  > >>>> me.
                                  > >>>>
                                  > >>>>
                                  > >>>>> Steve Stelzer
                                  > >>>>
                                  > >>>> I thought that livestock produced methane, which was a renewable? Just
                                  > >>>> Kidding  ; )  Although I appreciate information of this sort, I am more
                                  > >>>> concerned that this discussion group stays on target.
                                  > >>>>
                                  > >>>> By the way, I have been doing a great deal of looking around in my
                                  > >>>
                                  > >> spare
                                  > >>
                                  > >>>> time (which is not much) at solar air conditioners. There a number of
                                  > >>>> alternatives out there. It sounds strange until you view solar as an
                                  > >>>
                                  > >>> energy
                                  > >>>
                                  > >>>
                                  > >>>> source (heat). Most solar air conditioners work by a process called
                                  > >>>> adsorption. An efficient, economical solar a/c system, that could be
                                  > >>>
                                  > >> used
                                  > >>
                                  > >>> in
                                  > >>>
                                  > >>>
                                  > >>>> residential cooling would be an important contribution to renewable
                                  > >>>
                                  > >>> energy.
                                  > >>>
                                  > >>>
                                  > >>>> Think of the amount of heat generated in this city by a/c and the
                                  > >>>
                                  > >> amount
                                  > >>
                                  > >>> of
                                  > >>>
                                  > >>>
                                  > >>>> electricity that is wasted producing this heat.
                                  > >>>>
                                  > >>>> The adsorption units that I have looked at use either ammonia
                                  > >>>
                                  > >>> (refrigerant)
                                  > >>>
                                  > >>>
                                  > >>>> and calcium chloride (absorber) (or some other chemical) or water and
                                  > >>>
                                  > >>> silica
                                  > >>>
                                  > >>>
                                  > >>>> gel. The water and silica gel seems most promising to me. Ammonia is
                                  > >>>
                                  > >> too
                                  > >>
                                  > >>>> dangerous to have inside my house and it makes it difficult to work out
                                  > >>>
                                  > >> a
                                  > >>
                                  > >>>> system in which I can keep it outside. Water, however, is safe and when
                                  > >>>
                                  > >> it
                                  > >>
                                  > >>>> evaporates, absorbs a great deal of heat.
                                  > >>>>
                                  > >>>> There is also a solid state alternative that I have not had much
                                  > >>>
                                  > >>> opportunity
                                  > >>>
                                  > >>>
                                  > >>>> to explore. They use solid state refrigerators in small outdoor
                                  > >>>
                                  > >> coolers.
                                  > >>
                                  > >>>> When you pass a 12V current through the diode, one side gets hot and
                                  > >>>
                                  > >> the
                                  > >>
                                  > >>>> other side gets cool. Perhaps, we could use the hot side to pre-heat
                                  > >>>
                                  > >> our
                                  > >>
                                  > >>>> water to the hot water heater and the cold side to chill water that
                                  > >>>
                                  > >> could
                                  > >>
                                  > >>> be
                                  > >>>
                                  > >>>
                                  > >>>> used to cool the house, if needed. The unit could be attached to solar
                                  > >>>> panels that produce the 12V current. The hotter it is outside, the
                                  > >>>
                                  > >> harder
                                  > >>
                                  > >>>> the unit works. I like that!
                                  > >>>>
                                  > >>>> Some helpful web sites:
                                  http://www.caddet-ee.org/nl_html/001_02.htm
                                  > >>>> http://www.adsorptionchiller.com/
                                  > >>>>
                                  > >>>> Billy Bell
                                  > >>>> PO Box 926
                                  > >>>> Fulshear, Texas 77441-0926
                                  > >>>>
                                  > >>>> 713-439-1115 Telephone
                                  > >>>> 281-346-0994 Fax
                                  > >>>>
                                  wmb@...
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>> Your use of Yahoo! Groups is subject to
                                  > >>>
                                  > >>
                                  http://docs.yahoo.com/info/terms/
                                  > >>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>>
                                  > >>>> Your use of Yahoo! Groups is subject to
                                  > >>>
                                  > >>
                                  http://docs.yahoo.com/info/terms/
                                  > >>
                                  > >>>>
                                  > >>>
                                  > >>>
                                  > >>>
                                  > >>>
                                  > >>>
                                  > >>> Your use of Yahoo! Groups is subject to
                                  > >>
                                  > >>
                                  http://docs.yahoo.com/info/terms/
                                  > >>
                                  > >>
                                  > >>
                                  > >>
                                  > >>
                                  > >> Your use of Yahoo! Groups is subject to
                                  http://docs.yahoo.com/info/terms/
                                  > >>
                                  > >
                                  > >
                                  > >
                                  > >
                                  > >
                                  > > Your use of Yahoo! Groups is subject to
                                  http://docs.yahoo.com/info/terms/
                                  > >
                                  > >
                                  > >
                                  > >
                                  > >
                                  > >
                                  > > 
                                  > >
                                  > > Your use of Yahoo! Groups is subject to
                                  http://docs.yahoo.com/info/terms/
                                  >
                                  >
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                                  Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
                                • Robert Johnston
                                  It took me awhile to find time to read the paper; thanks for sharing it! Here are a few comments/questions... 1. (Comment--anyone else reading this paper in
                                  Message 16 of 28 , Sep 5, 2001
                                    It took me awhile to find time to read the paper; thanks for sharing it!
                                    Here are a few comments/questions...

                                    1. (Comment--anyone else reading this paper in MS Word should note that in
                                    p. 2 there is a formatting glitch [at least in my installation of Word 2000]
                                    that makes the text jump from near the top of the first column to the top of
                                    the 2nd column, and then continue on the 1st column after a paragraph. If
                                    you have trouble making sense of that section, maybe this document did the
                                    same thing on your system as it did on mine).

                                    2. Mike, given the low efficiencies and high costs of PV, it seems
                                    inefficient and costly to do the schemes that use PV to drive vapor
                                    compression heat pumps. Yet that is what you spent much of the paper
                                    describing. I assume this is because that is what NASA sees as most suited
                                    to space (especially where cost doesn't matter). But for terrestrial
                                    applications, doesn't your review suggest that solar thermal heat engines
                                    would be the better way to go? If so, why not more work in that area (or
                                    did you just not choose to focus on it in your review)? (You did mention an
                                    interesting study in Sacramento, CA (Bergquam, et al, 1997)--any updates on
                                    the second phase of that study using evacuated tube solar collectors)?
                                    Seems to me that with metallized plastics, one could readily make a low cost
                                    trough concentrator. Not true?

                                    3. We've discussed this briefly in the past (I lost all my email due to
                                    computer glitch, so forgive me if I repeat earlier questions), but after
                                    your lab tour a couple years ago, I was wondering what the barriers to
                                    efficient vacuum insulation were, and you mentioned they were hard to
                                    fabricate. I've been wondering, what if you had a dynamic system? E.g.,
                                    what if your house insulation were cheaper vacuum panels that may have
                                    pinhole leaks but which are actively pumped by a vacuum pump to maintain
                                    insulation? The vacuum could be removed if it were desirable for heat
                                    transfer purposes to remove the insulation (e.g., maybe at night you'd
                                    remove it in the spring and fall to allow cooling of the home interior, or
                                    maybe on sunny mild winter days you'd remove it to allow heat into the
                                    house). Then it could be reapplied if needed for insulation again.
                                    Probably crazy idea, but what do you think? I suspect your answer will be
                                    that to effectively insulate, you have to get a SUPER vacuum so it isn't
                                    practical to do this, e.g., would require a two stage vaccuum pump and long
                                    pumping times, but thought I'd ask. Do you happen to have a good reference
                                    for vacuum pressure vs. insulation ability (R value or something)? What is
                                    the vacuum pressure in your test refrigerator vacuum panels in the lab?

                                    4. Why haven't solar regenerated dessicant systems found more use? Why
                                    couldn't you combine that kind of trying with some of the techniques like
                                    cool water tubes (see separate discussion with Kim, LaVerne Williams) to
                                    have dry cool air/thermal mass?

                                    5. I was curious about this conclusion: "Engineering trade-off studies
                                    have shown that with current technology, vapor compression heat pumps have a
                                    distinct mass advantage over thermally driven heat pumps for human
                                    spacecraft and planetary base cooling (Ewert, 1993) (Swanson, 1993). The
                                    thermal heat pumps have lower coefficients of performance and thus need to
                                    reject a large amount of relatively low temperature waste heat. In space
                                    there is no atmospheric heat sink and heat rejection must be via thermal
                                    radiation. This means larger, heavier radiators for the thermal control
                                    system, leading to higher launch-to-orbit costs." While true in space, is
                                    it true for planetary base cooling? Why couldn't you use the planetary soil
                                    to build radiators? For example, what if you pulverized it to a powder,
                                    mixed it with a binder, and molded it? A relatively small mass of binder
                                    would enable large mass of radiator. Or, maybe just use the planet surface
                                    as a heat sink (perhaps after shielding it with aluminized film), with fluid
                                    circulating in pipes buried beneath the surface. Just wondering; seemed
                                    like the planet itself was an untapped resource...

                                    6. Elastomers/rubber undergo heating/cooling during stretching/retraction.
                                    I've seen proposals (I think even funded by NBS) to use elastomers as
                                    refrigerants in heat pumps, replacing the gas with an elastomer undergoing
                                    cyclic mechanical deformation. Right now I can't see how that would
                                    necessarily help you in solar, but just curious if you'd run across it in
                                    your reading.

                                    Thanks for your comments,

                                    Robert Johnston


                                    -----Original Message-----
                                    From: Mike Ewert [mailto:mike.ewert@...]
                                    Sent: Tuesday, September 04, 2001 8:32 AM
                                    To: hreg@yahoogroups.com
                                    Subject: RE: [hreg] Solar Air Conditioners


                                    Here is a review paper I did a while back on solar AC and heat pumps.
                                  • LaVerne Williams
                                    Robert: Now you have a little more about why the insurance industry is trying to take mold coverage out of our insurance policies. The insurance companies are
                                    Message 17 of 28 , Sep 6, 2001
                                      Robert: 
                                      Now you have a little more about why the insurance industry is trying to take mold coverage out of our insurance policies. The insurance companies are who the attorneys are going after.  Listen to Tom Tynon on KTRH Radio, AM740.
                                       
                                      LaVerne A. Williams, AIA
                                      laverne@...
                                      Environment Associates, Architects & Consultants
                                      5828 Langfield Road
                                      Houston, TX 77092-1429
                                      713.528.0000
                                       
                                       
                                      ----- Original Message -----
                                      Sent: Wednesday, September 05, 2001 8:06 PM
                                      Subject: RE: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                      Thanks Laverne for the clarification.  I just remember that your comments were sufficiently sobering that
                                      I started looking for other avenues.  Your new comments only add to those concerns.  I think you are
                                      right about the mold and mildew liabilities.  It may be tougher for the class action lawyers since there isn't
                                      a single deep pocketed company like Johns Mansville, but I imagine there are enough major builders like
                                      U.S. Homes etc. that they can find enough targets to keep them in BMW's for a few years at least.
                                       
                                      Robert
                                      -----Original Message-----
                                      From: LaVerne Williams [mailto:wa@...]
                                      Sent: Wednesday, September 05, 2001 1:05 PM
                                      To: hreg@yahoogroups.com
                                      Subject: Re: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                      Dear Kim & Garth & Robert Johnston:
                                       
                                      Robert:  You have a good memory.  I wish I could comment in detail but my current commitments are not leaving me much free time at all, but Kim is not talking about a "cool tube" concept, which would be a disaster health wise in probably most of Texas.  I think he is describing a system that is similar to a system being promoted from Dallas that has piping (metal. I think) that runs around a room with troughs below to catch the condensate to drain it.  I believe the McDermott Engineering building in West Houston used the system for a while but I believe they abandoned it.
                                       
                                      Being only 100 miles from Houston, Kim & Garth, I wouldn't recommend such a system here or even in dessert areas.  They are having terrific mold problems in desert area homes.  I am not sure why because I am not currently working on any projects in such areas, but it may be a combination of tight homes and the use of "swamp type coolers".  Or it just may be tight homes with conventional HVAC systems and poor construction not having a drainage plane or oversized cooling systems.  Of course, compared to conditions that are set up to have mold growth in dessert areas means horrendous blossoming of mold growth in the humid Gulf Coast and Central Texas areas.
                                       
                                      Anyway, mold will eventually form in the trough and if you could see what I am experiencing with people who have come to me because of very serious health problems they are having from mold in their houses, you would do everything possible to prevent mold from forming. (I'm working with a couple right now who decided to design and build their own house and now his wife has had around 17 strokes in her brain (MRI confirmed) primarily because of what mold  (and formaldehyde in common building materials)  can do.  They also have twins who are 5 years old who have only developed to that of 2 year olds, and one of them is not showing any signs of recovery.   I am helping them create a safe haven until we can do something more permanent for them).  I also have an Industrial Hygienist friend who is involved as an expert witness in over 1500 lawsuits because of mold growth and health problems with houses and buildings.  From what he has seen, the litigation concerning mold in buildings will dwarf what happened with asbestos in buildings
                                       
                                      Hope this helps. 
                                       
                                      To Everyone:  Molds kill.   Do everything you can to make your home mold free!!!  It is not something to take lightly.  Anytime and any place the relative humidity inside a home goes over 60% RH, mold grows!  (Aim for 50% RH or less year-round)  This woman was in such perfect health before they built their home 7 years ago that she worked out 2 hours a day!  Now she can barely care for herself and her twins.  They have had to abandon their house.
                                       
                                      LaVerne A. Williams, AIA
                                      laverne@...
                                      Environment Associates, Architects & Consultants
                                      5828 Langfield Road
                                      Houston, TX 77092-1429
                                      713.528.0000
                                       
                                       
                                       
                                       

                                    • Robert Johnston
                                      I could see how they might sue the insurance companies for repair or even replacement costs, but it seems difficult to imagine how they could pin the insurance
                                      Message 18 of 28 , Sep 6, 2001
                                        I could see how they might sue the insurance companies for repair or even replacement costs, but it seems difficult to imagine how they could pin the insurance companies with the any punitive damages.  If this is true, then the overall liability to the insurance companies wouldn't be astronomical.  But I'm no lawyer.  They do some amazing things, especially in Texas.  It is a wonder sometimes that there are any companies left selling anything!  Maybe eventually everyone will build everything themselves and have only themselves to blame for failure.  I don't know what lawyers would do for a living then.  Probably sue parents on behalf of children upset that they were born into such a miserable world.  :-)
                                         
                                        Robert
                                        -----Original Message-----
                                        From: LaVerne Williams [mailto:wa@...]
                                        Sent: Thursday, September 06, 2001 12:40 PM
                                        To: hreg@yahoogroups.com
                                        Subject: Re: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                        Robert: 
                                        Now you have a little more about why the insurance industry is trying to take mold coverage out of our insurance policies. The insurance companies are who the attorneys are going after.  Listen to Tom Tynon on KTRH Radio, AM740.
                                         
                                        LaVerne A. Williams, AIA
                                        laverne@...
                                        Environment Associates, Architects & Consultants
                                        5828 Langfield Road
                                        Houston, TX 77092-1429
                                        713.528.0000
                                         
                                         
                                        ----- Original Message -----
                                        Sent: Wednesday, September 05, 2001 8:06 PM
                                        Subject: RE: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                        Thanks Laverne for the clarification.  I just remember that your comments were sufficiently sobering that
                                        I started looking for other avenues.  Your new comments only add to those concerns.  I think you are
                                        right about the mold and mildew liabilities.  It may be tougher for the class action lawyers since there isn't
                                        a single deep pocketed company like Johns Mansville, but I imagine there are enough major builders like
                                        U.S. Homes etc. that they can find enough targets to keep them in BMW's for a few years at least.
                                         
                                        Robert
                                        -----Original Message-----
                                        From: LaVerne Williams [mailto:wa@...]
                                        Sent: Wednesday, September 05, 2001 1:05 PM
                                        To: hreg@yahoogroups.com
                                        Subject: Re: [hreg] Solar Air Conditioners (LaVerne Williams?)

                                        Dear Kim & Garth & Robert Johnston:
                                         
                                        Robert:  You have a good memory.  I wish I could comment in detail but my current commitments are not leaving me much free time at all, but Kim is not talking about a "cool tube" concept, which would be a disaster health wise in probably most of Texas.  I think he is describing a system that is similar to a system being promoted from Dallas that has piping (metal. I think) that runs around a room with troughs below to catch the condensate to drain it.  I believe the McDermott Engineering building in West Houston used the system for a while but I believe they abandoned it.
                                         
                                        Being only 100 miles from Houston, Kim & Garth, I wouldn't recommend such a system here or even in dessert areas.  They are having terrific mold problems in desert area homes.  I am not sure why because I am not currently working on any projects in such areas, but it may be a combination of tight homes and the use of "swamp type coolers".  Or it just may be tight homes with conventional HVAC systems and poor construction not having a drainage plane or oversized cooling systems.  Of course, compared to conditions that are set up to have mold growth in dessert areas means horrendous blossoming of mold growth in the humid Gulf Coast and Central Texas areas.
                                         
                                        Anyway, mold will eventually form in the trough and if you could see what I am experiencing with people who have come to me because of very serious health problems they are having from mold in their houses, you would do everything possible to prevent mold from forming. (I'm working with a couple right now who decided to design and build their own house and now his wife has had around 17 strokes in her brain (MRI confirmed) primarily because of what mold  (and formaldehyde in common building materials)  can do.  They also have twins who are 5 years old who have only developed to that of 2 year olds, and one of them is not showing any signs of recovery.   I am helping them create a safe haven until we can do something more permanent for them).  I also have an Industrial Hygienist friend who is involved as an expert witness in over 1500 lawsuits because of mold growth and health problems with houses and buildings.  From what he has seen, the litigation concerning mold in buildings will dwarf what happened with asbestos in buildings
                                         
                                        Hope this helps. 
                                         
                                        To Everyone:  Molds kill.   Do everything you can to make your home mold free!!!  It is not something to take lightly.  Anytime and any place the relative humidity inside a home goes over 60% RH, mold grows!  (Aim for 50% RH or less year-round)  This woman was in such perfect health before they built their home 7 years ago that she worked out 2 hours a day!  Now she can barely care for herself and her twins.  They have had to abandon their house.
                                         
                                        LaVerne A. Williams, AIA
                                        laverne@...
                                        Environment Associates, Architects & Consultants
                                        5828 Langfield Road
                                        Houston, TX 77092-1429
                                        713.528.0000
                                         
                                         
                                         
                                         



                                        Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
                                      • Mike Ewert
                                        Robert, I hope I can answer all your questions. They are good ones. You re an inventor at heart, aren t you? 2. The conclusion I drew is that, although PV
                                        Message 19 of 28 , Sep 8, 2001
                                          Robert, I hope I can answer all your questions. They are good ones. You're
                                          an inventor at heart, aren't you?

                                          2. The conclusion I drew is that, although PV efficiency is low,
                                          refrigeration cycle efficiency is low for the thermal cycles, so the net
                                          "solar coefficient of performance" is similar for the 2 types of systems.
                                          Given that vapor compression and absorption heat pumps and solar thermal
                                          collectors are all more mature than PV, I expect the most progress in PV
                                          vapor compression refrigeration systems in the next 10 years.

                                          I have not followed up on Bergquam.

                                          3. Vacuum pumps take quite a bit of power. I suspect that is why they have
                                          only been used for cryogenic insulation systems. I have a reference for
                                          pressure vs. thermal resistance but I'll have to look for it at work.

                                          4. Cost, I guess. I think there is hope.

                                          5. Planetary soil (regolith) is a very good insulator. I suppose some day
                                          we may make things out of it, but I'm not sure if it will ever make good
                                          radiators.

                                          6. Yes, we have had some "rubber band" cooling system proposals. I don't
                                          think we have funded any. It just didn't seem practical how many bands you
                                          would have to have to provide significant cooling.

                                          -----Original Message-----
                                          From: Robert Johnston [mailto:rjohnsto@...]
                                          Sent: Wednesday, September 05, 2001 10:16 PM
                                          To: hreg@yahoogroups.com
                                          Subject: RE: [hreg] Solar Air Conditioners


                                          It took me awhile to find time to read the paper; thanks for sharing it!
                                          Here are a few comments/questions...

                                          1. (Comment--anyone else reading this paper in MS Word should note that in
                                          p. 2 there is a formatting glitch [at least in my installation of Word 2000]
                                          that makes the text jump from near the top of the first column to the top of
                                          the 2nd column, and then continue on the 1st column after a paragraph. If
                                          you have trouble making sense of that section, maybe this document did the
                                          same thing on your system as it did on mine).

                                          2. Mike, given the low efficiencies and high costs of PV, it seems
                                          inefficient and costly to do the schemes that use PV to drive vapor
                                          compression heat pumps. Yet that is what you spent much of the paper
                                          describing. I assume this is because that is what NASA sees as most suited
                                          to space (especially where cost doesn't matter). But for terrestrial
                                          applications, doesn't your review suggest that solar thermal heat engines
                                          would be the better way to go? If so, why not more work in that area (or
                                          did you just not choose to focus on it in your review)? (You did mention an
                                          interesting study in Sacramento, CA (Bergquam, et al, 1997)--any updates on
                                          the second phase of that study using evacuated tube solar collectors)?
                                          Seems to me that with metallized plastics, one could readily make a low cost
                                          trough concentrator. Not true?

                                          3. We've discussed this briefly in the past (I lost all my email due to
                                          computer glitch, so forgive me if I repeat earlier questions), but after
                                          your lab tour a couple years ago, I was wondering what the barriers to
                                          efficient vacuum insulation were, and you mentioned they were hard to
                                          fabricate. I've been wondering, what if you had a dynamic system? E.g.,
                                          what if your house insulation were cheaper vacuum panels that may have
                                          pinhole leaks but which are actively pumped by a vacuum pump to maintain
                                          insulation? The vacuum could be removed if it were desirable for heat
                                          transfer purposes to remove the insulation (e.g., maybe at night you'd
                                          remove it in the spring and fall to allow cooling of the home interior, or
                                          maybe on sunny mild winter days you'd remove it to allow heat into the
                                          house). Then it could be reapplied if needed for insulation again.
                                          Probably crazy idea, but what do you think? I suspect your answer will be
                                          that to effectively insulate, you have to get a SUPER vacuum so it isn't
                                          practical to do this, e.g., would require a two stage vaccuum pump and long
                                          pumping times, but thought I'd ask. Do you happen to have a good reference
                                          for vacuum pressure vs. insulation ability (R value or something)? What is
                                          the vacuum pressure in your test refrigerator vacuum panels in the lab?

                                          4. Why haven't solar regenerated dessicant systems found more use? Why
                                          couldn't you combine that kind of trying with some of the techniques like
                                          cool water tubes (see separate discussion with Kim, LaVerne Williams) to
                                          have dry cool air/thermal mass?

                                          5. I was curious about this conclusion: "Engineering trade-off studies
                                          have shown that with current technology, vapor compression heat pumps have a
                                          distinct mass advantage over thermally driven heat pumps for human
                                          spacecraft and planetary base cooling (Ewert, 1993) (Swanson, 1993). The
                                          thermal heat pumps have lower coefficients of performance and thus need to
                                          reject a large amount of relatively low temperature waste heat. In space
                                          there is no atmospheric heat sink and heat rejection must be via thermal
                                          radiation. This means larger, heavier radiators for the thermal control
                                          system, leading to higher launch-to-orbit costs." While true in space, is
                                          it true for planetary base cooling? Why couldn't you use the planetary soil
                                          to build radiators? For example, what if you pulverized it to a powder,
                                          mixed it with a binder, and molded it? A relatively small mass of binder
                                          would enable large mass of radiator. Or, maybe just use the planet surface
                                          as a heat sink (perhaps after shielding it with aluminized film), with fluid
                                          circulating in pipes buried beneath the surface. Just wondering; seemed
                                          like the planet itself was an untapped resource...

                                          6. Elastomers/rubber undergo heating/cooling during stretching/retraction.
                                          I've seen proposals (I think even funded by NBS) to use elastomers as
                                          refrigerants in heat pumps, replacing the gas with an elastomer undergoing
                                          cyclic mechanical deformation. Right now I can't see how that would
                                          necessarily help you in solar, but just curious if you'd run across it in
                                          your reading.

                                          Thanks for your comments,

                                          Robert Johnston


                                          -----Original Message-----
                                          From: Mike Ewert [mailto:mike.ewert@...]
                                          Sent: Tuesday, September 04, 2001 8:32 AM
                                          To: hreg@yahoogroups.com
                                          Subject: RE: [hreg] Solar Air Conditioners


                                          Here is a review paper I did a while back on solar AC and heat pumps.






                                          Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                                        • Robert Johnston
                                          Thanks, Mike. Regarding your responses to the numbered points: 2. Good point. I hear so much more about PV, though (I think it is more
                                          Message 20 of 28 , Sep 9, 2001
                                            Thanks, Mike.

                                            Regarding your responses to the numbered points:

                                            2. Good point. I hear so much more about PV, though (I think it is more
                                            "clean"/"elegant"/"sexy" than thermal technologies), that I wonder if the
                                            thermal arena doesn't still have some significant untapped potential. In
                                            particular, with new materials invented constantly, I should think this
                                            could continue to be developed.

                                            3. If you get a chance, I'd be curious to know the curve. Actually, I
                                            should look it up in my CRC Handbook. I wouldn't be surprised if it is
                                            in there.

                                            4. Sometime I'll have to root around and see what has been done here since
                                            the last I read about it. I think there is some potential here. What I
                                            like
                                            is that it could be readily supplemented by gas or wood burning, so one
                                            could
                                            still get by even off-grid on overcast/rainy days.

                                            5. It is a good INSULATOR? Really! I would have thought it to be a
                                            conductor.
                                            I thought those moon rocks were high in iron and other metals. Is planetary
                                            soil a lot different than moonrocks? I assume we're talking about Mars.
                                            Of course, upon reflection, I suppose that for a material to be a good
                                            radiator on a planet you're really talking about black body radiation rather
                                            than conduction of heat to the atmosphere. That's different than on earth.
                                            Is the atmospheric pressure on Mars lower than on earth?

                                            6. The one I know of was a consortium that included a pretty major
                                            professor
                                            in rubber elasticity theory at the Univ. of Cincinnati, Prof. James Mark.
                                            You
                                            wouldn't of course use rubber banks as in the bands you buy at the office
                                            supply store. More likely you'd use just a handful of very large bands.
                                            The
                                            key is to minimize hysteretic losses, so perfect endlinked networks are
                                            preferred,
                                            which is why J. Mark was involved, since he is an expert on endlinked
                                            polysiloxane
                                            networks.

                                            Robert

                                            -----Original Message-----
                                            From: Mike Ewert [mailto:mike.ewert@...]
                                            Sent: Saturday, September 08, 2001 3:20 PM
                                            To: hreg@yahoogroups.com
                                            Subject: RE: [hreg] Solar Air Conditioners


                                            Robert, I hope I can answer all your questions. They are good ones. You're
                                            an inventor at heart, aren't you?

                                            2. The conclusion I drew is that, although PV efficiency is low,
                                            refrigeration cycle efficiency is low for the thermal cycles, so the net
                                            "solar coefficient of performance" is similar for the 2 types of systems.
                                            Given that vapor compression and absorption heat pumps and solar thermal
                                            collectors are all more mature than PV, I expect the most progress in PV
                                            vapor compression refrigeration systems in the next 10 years.

                                            I have not followed up on Bergquam.

                                            3. Vacuum pumps take quite a bit of power. I suspect that is why they have
                                            only been used for cryogenic insulation systems. I have a reference for
                                            pressure vs. thermal resistance but I'll have to look for it at work.

                                            4. Cost, I guess. I think there is hope.

                                            5. Planetary soil (regolith) is a very good insulator. I suppose some day
                                            we may make things out of it, but I'm not sure if it will ever make good
                                            radiators.

                                            6. Yes, we have had some "rubber band" cooling system proposals. I don't
                                            think we have funded any. It just didn't seem practical how many bands you
                                            would have to have to provide significant cooling.

                                            -----Original Message-----
                                            From: Robert Johnston [mailto:rjohnsto@...]
                                            Sent: Wednesday, September 05, 2001 10:16 PM
                                            To: hreg@yahoogroups.com
                                            Subject: RE: [hreg] Solar Air Conditioners


                                            It took me awhile to find time to read the paper; thanks for sharing it!
                                            Here are a few comments/questions...

                                            1. (Comment--anyone else reading this paper in MS Word should note that in
                                            p. 2 there is a formatting glitch [at least in my installation of Word 2000]
                                            that makes the text jump from near the top of the first column to the top of
                                            the 2nd column, and then continue on the 1st column after a paragraph. If
                                            you have trouble making sense of that section, maybe this document did the
                                            same thing on your system as it did on mine).

                                            2. Mike, given the low efficiencies and high costs of PV, it seems
                                            inefficient and costly to do the schemes that use PV to drive vapor
                                            compression heat pumps. Yet that is what you spent much of the paper
                                            describing. I assume this is because that is what NASA sees as most suited
                                            to space (especially where cost doesn't matter). But for terrestrial
                                            applications, doesn't your review suggest that solar thermal heat engines
                                            would be the better way to go? If so, why not more work in that area (or
                                            did you just not choose to focus on it in your review)? (You did mention an
                                            interesting study in Sacramento, CA (Bergquam, et al, 1997)--any updates on
                                            the second phase of that study using evacuated tube solar collectors)?
                                            Seems to me that with metallized plastics, one could readily make a low cost
                                            trough concentrator. Not true?

                                            3. We've discussed this briefly in the past (I lost all my email due to
                                            computer glitch, so forgive me if I repeat earlier questions), but after
                                            your lab tour a couple years ago, I was wondering what the barriers to
                                            efficient vacuum insulation were, and you mentioned they were hard to
                                            fabricate. I've been wondering, what if you had a dynamic system? E.g.,
                                            what if your house insulation were cheaper vacuum panels that may have
                                            pinhole leaks but which are actively pumped by a vacuum pump to maintain
                                            insulation? The vacuum could be removed if it were desirable for heat
                                            transfer purposes to remove the insulation (e.g., maybe at night you'd
                                            remove it in the spring and fall to allow cooling of the home interior, or
                                            maybe on sunny mild winter days you'd remove it to allow heat into the
                                            house). Then it could be reapplied if needed for insulation again.
                                            Probably crazy idea, but what do you think? I suspect your answer will be
                                            that to effectively insulate, you have to get a SUPER vacuum so it isn't
                                            practical to do this, e.g., would require a two stage vaccuum pump and long
                                            pumping times, but thought I'd ask. Do you happen to have a good reference
                                            for vacuum pressure vs. insulation ability (R value or something)? What is
                                            the vacuum pressure in your test refrigerator vacuum panels in the lab?

                                            4. Why haven't solar regenerated dessicant systems found more use? Why
                                            couldn't you combine that kind of trying with some of the techniques like
                                            cool water tubes (see separate discussion with Kim, LaVerne Williams) to
                                            have dry cool air/thermal mass?

                                            5. I was curious about this conclusion: "Engineering trade-off studies
                                            have shown that with current technology, vapor compression heat pumps have a
                                            distinct mass advantage over thermally driven heat pumps for human
                                            spacecraft and planetary base cooling (Ewert, 1993) (Swanson, 1993). The
                                            thermal heat pumps have lower coefficients of performance and thus need to
                                            reject a large amount of relatively low temperature waste heat. In space
                                            there is no atmospheric heat sink and heat rejection must be via thermal
                                            radiation. This means larger, heavier radiators for the thermal control
                                            system, leading to higher launch-to-orbit costs." While true in space, is
                                            it true for planetary base cooling? Why couldn't you use the planetary soil
                                            to build radiators? For example, what if you pulverized it to a powder,
                                            mixed it with a binder, and molded it? A relatively small mass of binder
                                            would enable large mass of radiator. Or, maybe just use the planet surface
                                            as a heat sink (perhaps after shielding it with aluminized film), with fluid
                                            circulating in pipes buried beneath the surface. Just wondering; seemed
                                            like the planet itself was an untapped resource...

                                            6. Elastomers/rubber undergo heating/cooling during stretching/retraction.
                                            I've seen proposals (I think even funded by NBS) to use elastomers as
                                            refrigerants in heat pumps, replacing the gas with an elastomer undergoing
                                            cyclic mechanical deformation. Right now I can't see how that would
                                            necessarily help you in solar, but just curious if you'd run across it in
                                            your reading.

                                            Thanks for your comments,

                                            Robert Johnston


                                            -----Original Message-----
                                            From: Mike Ewert [mailto:mike.ewert@...]
                                            Sent: Tuesday, September 04, 2001 8:32 AM
                                            To: hreg@yahoogroups.com
                                            Subject: RE: [hreg] Solar Air Conditioners


                                            Here is a review paper I did a while back on solar AC and heat pumps.






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