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Re: [hreg] Solar Air Conditioners

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  • 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 1 of 28 , Aug 31, 2001
    • 0 Attachment
      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 2 of 28 , Aug 31, 2001
      • 0 Attachment
        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 3 of 28 , Aug 31, 2001
        • 0 Attachment
          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 4 of 28 , Aug 31, 2001
          • 0 Attachment
            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 5 of 28 , Sep 1, 2001
            • 0 Attachment
              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 6 of 28 , Sep 1, 2001
              • 0 Attachment
                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 7 of 28 , Sep 1, 2001
                • 0 Attachment
                  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 8 of 28 , Sep 4, 2001
                  • 0 Attachment
                    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 9 of 28 , Sep 4, 2001
                    • 0 Attachment
                      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@...





                      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
                      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 10 of 28 , Sep 5, 2001
                      • 0 Attachment
                        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 11 of 28 , Sep 5, 2001
                        • 0 Attachment
                          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/
                          >




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                          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 12 of 28 , Sep 5, 2001
                          • 0 Attachment
                            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/
                            >>
                            >>>>
                            >>>
                            >>>
                            >>>
                            >>>
                            >>>
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                          • 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 13 of 28 , Sep 5, 2001
                            • 0 Attachment
                              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@...
                              > >>>>
                              > >>>>
                              > >>>>
                              > >>>>
                              > >>>>
                              > >>>> 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 14 of 28 , Sep 5, 2001
                              • 0 Attachment
                                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
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                              • 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 15 of 28 , Sep 5, 2001
                                • 0 Attachment
                                  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 16 of 28 , Sep 6, 2001
                                  • 0 Attachment
                                    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 17 of 28 , Sep 6, 2001
                                    • 0 Attachment
                                      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 18 of 28 , Sep 8, 2001
                                      • 0 Attachment
                                        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 19 of 28 , Sep 9, 2001
                                        • 0 Attachment
                                          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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