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Re: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

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  • Jim & Janet
    Message Gary Beck Eco-Holdings LLC Wrote: Is there a light colored solar cell? Well, the reason the cells surface is dark is to help it absorb as much light
    Message 1 of 18 , Jan 6, 2005
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      Message
       
      Gary Beck
      Eco-Holdings LLC
       
      Wrote:    Is there a light colored solar cell?
       
      Well, the reason the cells surface is dark is to help it absorb as much light energy as possible. A light colored cell would reflect more photons reducing the cells output significantly. If you looked at the cell surface under magnification, you would see the surface is jagged and rough to increase the surface receiving sunlight. The heat is just an unwanted byproduct.
      Possibly the quickest way to improve module efficiency by 1 to 2 % is to figure how to eliminate resistance at the interconnections between individual cells. No one has yet figured how to effectively 'solder' wires to silicon. This is why most PV manufacturers advertise the individual cell efficiency as slightly higher than the overall module efficiency. That's driving the industry away from silicon and toward other methods of electrical production; spinach for example.
      Jim Duncan
    • Robert Johnston
      Am I missing something, or is this much to do about nothing? Sure, any radiant energy captured by a solar cell is not reflected back into space immediately.
      Message 2 of 18 , Jan 7, 2005
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        Message

        Am I missing something, or is this much to do about nothing?

         

        Sure, any radiant energy captured by a solar cell is not reflected back into space immediately.  But:  (a) even if you had a perfect mirror there instead, not all reflected light would make it back to space [light scattering, greenhouse effect, etc.]; (b) surely one can coat the cell with a reflective surface that transmits UV (or whatever wavelengths the solar cell optimally uses) and reflects others; (c) if the solar cell weren’t there, it is unlikely that the surface that would be there instead would reflect light back perfectly either.  It would absorb at least a portion of it and the radiant energy would be converted to heat.  Even biomass merely stores it as potential energy that is later released as heat by burning, digestion, etc.  And, (d) some of the absorbed radiation that is converted into heat will eventually be emitted back to space.  Ever notice how much the earth cools on a clear night with no cloud cover?  That is heat loss by a relatively cool substrate, e.g., the earth at 15-30°C.

         

        I don’t think we are talking about a big deal here.  Even if 1% of the U.S. land mass were covered with solar cells, that would not absorb as much radiant energy as our forests do today.

         

        Why not just do a radiant energy balance on the planet?  Smalley’s presentation says in 2003 we used 14 terawatts (TW) of energy per day.  This compares to 165,000 TW of sunlight striking the planet per day.  Even at the 50 TW he projects we’ll need in 2050, that is only 0.03% of the sun’s radiant energy being needed.  If we have perfectly absorbent solar cells that absorb all the solar spectrum, and if they operate at only 10% solar efficiency, that means that the solar cells necessary to supply our energy needs in 2050 (assuming we go 100% solar cells for energy needs) would absorb just 0.3% of the sun’s radiant flux on earth.  Do you think we’d even notice that?  Remember, a significant fraction of that 0.3% is already absorbed by whatever substrate is there today.  We’re talking about an extremely small effect here!

         

        There remains a debate about whether global warming is real or not.  But if we assume it is, I think most scientists would argue that the cause of global warming is not the heat we are emitting but rather the greenhouse effect, e.g., the heat we are trapping.  If we quit using fossil fuels and drastically reduce greenhouse gas emissions, any additional heat absorbed by solar cells would be more than compensated for by the increased emission to space.  In other words, we can afford to convert more energy into sensable heat so long as we have less greenhouse effect.

         

        If you are concerned about localized effects, such as in cities, there would be ways to mitigate it.  For instance, you could make covered parking lots, with the cells on the roof; this would merely absorb what would have otherwise been absorbed by the asphalt.  There are indeed efforts to convert roofing membranes from black rubber sheeting or asphalt to white TPO roofing membranes.  However, as happened at MinuteMaid Park, mold and mildew can quickly stain a white roof to a dark color, so it is not a very robust approach today, and I’m not sure what the long term contribution to urban micro-climates is.  Personally, I’d prefer a dark roof since it is more UV stable and should last longer.  That makes sense from an economic and sustainability standpoint.  If I were a roofing membrane installer, though, I’d sure rather work on a white roof!  (At least in Houston in the summer)!

         

        Robert Johnston

         

         

        -----Original Message-----
        From: Gary Beck [mailto:eco@...]
        Sent: Thursday, January 06, 2005 9:55 AM
        To: hreg@yahoogroups.com
        Subject: RE: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

         

        Incredible breakthoughs or not, one thing I have to point out is that solar cells should not be thought of as free or even renewable. The energy they capture is not free. They make electricity by capturing energy that is otherwise reflected back into space. All this captured energy will be released as sensable heat. 

         

        The other point is that every solar cell I have ever seen is very dark color and that on a sunny day I assume you can fry and egg on them during operation.  And they would remain warm for a few extra hours each night.  Sounds like a hot city that has 1/2 of the area of every roof covered in in solar cells. 

         

        This vision of a 'solar roof on every house' is the opposite of significant eco design efforts to try to cool cities by adopting building specifications changing commercial roof colors to white and residential roofs to very light shingles (plus a cooler roof means cooler living working space). Or better yet like USGBC-LEED and other efforts that support 'green' garden roof on new commerical buildings. 

         

        What is the best approach to satisfy both concerns? Is there a light colored solar cell? Any one have a design for a solar cell garden roof?

         

        Gary Beck

        Eco-Holdings LLC

         

        I read ocasionally Scientific American, Discovery, Science etc. - they are great for 'what if' and 'think about this' , but not very good predictors at all. What were they saying about fuel cells 10 or 20 years ago? My son get Popular Science - a recent article is called "Hydrogen's Bomb - Decoding the Hype".  My favorite recent new science release? The spinach plant that is designed to generate electricity (no joke) (here's a joke: It is a good thing since will require more candle lit dinners - cause after you finish your salad it's light out!) 

        -----Original Message-----
        From: Roxanne Boyer [mailto:rox1@...]
        Sent: Tuesday, January 04, 2005 10:20 PM
        To: hreg@yahoogroups.com
        Subject: Re: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

        Mr. Malone,

        I quite dissagree with you on many of these issues, and so do most scientists.  Read any of the articles today on energy in Scientific American, Physics Today, Discovery, Science, .... and you will find that our current oil consumption trends can only be sustained to about 2050, plus or minus 20 years.  Renewable energy is growing exponencially.  Europe is aiming for 20% renewables by 2020.  I believe many of the US States already have similar goals and many more will join in as time goes on.  There will be a change within the next lifespan.

         

        Even the "Oil" companies realize this and have published reports that say so.  They are starting to call themselves "Energy" companies and investing quite heavily in renewable energy.  See Shell Solar, Shell Wind, Shell Renewables, BP Solar, GE Solar, GE Wind, for example.  And if the oil companies don't lead, the electronics companies will.  Sharp is already the leading manufacturer of solar cells.

         

        I don't know how you did your math about not enough solar energy in New Jersey (is that the state with the highest energy to land ratio and the least sunny state?).  But the math I have done shows that I can supply all of my Houston household electrical needs (averaged) by covering half of my roof with solar panels.  No breakthrough technology needed; it already exists.  If you trend retail electric prices and solar PV prices, you will see the cost cross in the year 2025 - then it will be more economical to buy PV than grid electricity!

         

        If you read up on the technical progress of photoelectrics, you will see incredible breakthroughs in the last 10 years.  Right now, solar cells are expensive because production can not keep up with demand.  And new record breaking production facillities are being opened each year.

         

        If you want a "heart felt" change, read the July-August issue of Renewable Energy World each year and see the growth of RE for yourself.  It is amazing.  Maybe we can discuss some of the facts at the next HREG meeting, Sunday, 2:00pm, Jan 30th at TSU.

        Sincerely,

        Chris

         

         

        ----- Original Message -----

        Sent: Monday, January 03, 2005 8:43 PM

        Subject: RE: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

         

         

        All this discussion is interesting and heart felt.  The following is not intended as a rant, but to put our problem in perspective.

         

        Our government, both parties, is so tied to big oil money, .

        It would take solar panels covering every square inch of the state of New Jersey just to equal the energy used in New Jersey.  So the size of the oil dependency is almost beyond our reason.

         

        A breakthrough, one not foreseeable by current science is most likely the only hope in the US.  Outside the US there may be some help because of the different mind set of the non US-Oil cartel.

         

        China is graduating more engineers & scientists each year than the US graduates all college students of all degree fields.  China has a massive energy problem.  They also have a growing economy that it partly controlled & partly free market.  As they inevitably pass the US number of educated citizens (check out our schools systems if you doubt this) and the controlling government forces capital & research in to alternative energy research because of their vast needs and lack of resources they may turn this thing around.

         

        I hope I live long enough to see the beginning.

        In the interim, conservation, voting, getting activity in politics may be the only drop in the bucket we have. I hope I’m wrong.

         

         

        J. Patrick Malone

         

        -----Original Message-----
        From: Robert Johnston [mailto:junk1@...]
        Sent: Monday, January 03, 2005 7:36 PM
        To: hreg@yahoogroups.com
        Subject: RE: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

         

         

      • Richard D. Kelley
        Mountains out a molehill? Buy some panels a put that Texas cooker to work. ... From: Robert Johnston [SMTP:junk1@plastability.com] Sent: Friday, January 07,
        Message 3 of 18 , Jan 7, 2005
        • 0 Attachment
          Mountains out a molehill? Buy some panels a put that Texas cooker to work.


          -----Original Message-----
          From: Robert Johnston [SMTP:junk1@...]
          Sent: Friday, January 07, 2005 4:57 PM
          To: hreg@yahoogroups.com
          Subject: RE: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

          << File: ATT00029.htm >> Am I missing something, or is this much to do about nothing?



          Sure, any radiant energy captured by a solar cell is not reflected back
          into space immediately. But: (a) even if you had a perfect mirror
          there instead, not all reflected light would make it back to space
          [light scattering, greenhouse effect, etc.]; (b) surely one can coat the
          cell with a reflective surface that transmits UV (or whatever
          wavelengths the solar cell optimally uses) and reflects others; (c) if
          the solar cell weren't there, it is unlikely that the surface that would
          be there instead would reflect light back perfectly either. It would
          absorb at least a portion of it and the radiant energy would be
          converted to heat. Even biomass merely stores it as potential energy
          that is later released as heat by burning, digestion, etc. And, (d)
          some of the absorbed radiation that is converted into heat will
          eventually be emitted back to space. Ever notice how much the earth
          cools on a clear night with no cloud cover? That is heat loss by a
          relatively cool substrate, e.g., the earth at 15-30°C.



          I don't think we are talking about a big deal here. Even if 1% of the
          U.S. land mass were covered with solar cells, that would not absorb as
          much radiant energy as our forests do today.



          Why not just do a radiant energy balance on the planet? Smalley's
          presentation says in 2003 we used 14 terawatts (TW) of energy per day.
          This compares to 165,000 TW of sunlight striking the planet per day.
          Even at the 50 TW he projects we'll need in 2050, that is only 0.03% of
          the sun's radiant energy being needed. If we have perfectly absorbent
          solar cells that absorb all the solar spectrum, and if they operate at
          only 10% solar efficiency, that means that the solar cells necessary to
          supply our energy needs in 2050 (assuming we go 100% solar cells for
          energy needs) would absorb just 0.3% of the sun's radiant flux on earth.
          Do you think we'd even notice that? Remember, a significant fraction of
          that 0.3% is already absorbed by whatever substrate is there today.
          We're talking about an extremely small effect here!



          There remains a debate about whether global warming is real or not. But
          if we assume it is, I think most scientists would argue that the cause
          of global warming is not the heat we are emitting but rather the
          greenhouse effect, e.g., the heat we are trapping. If we quit using
          fossil fuels and drastically reduce greenhouse gas emissions, any
          additional heat absorbed by solar cells would be more than compensated
          for by the increased emission to space. In other words, we can afford
          to convert more energy into sensable heat so long as we have less
          greenhouse effect.



          If you are concerned about localized effects, such as in cities, there
          would be ways to mitigate it. For instance, you could make covered
          parking lots, with the cells on the roof; this would merely absorb what
          would have otherwise been absorbed by the asphalt. There are indeed
          efforts to convert roofing membranes from black rubber sheeting or
          asphalt to white TPO roofing membranes. However, as happened at
          MinuteMaid Park, mold and mildew can quickly stain a white roof to a
          dark color, so it is not a very robust approach today, and I'm not sure
          what the long term contribution to urban micro-climates is. Personally,
          I'd prefer a dark roof since it is more UV stable and should last
          longer. That makes sense from an economic and sustainability
          standpoint. If I were a roofing membrane installer, though, I'd sure
          rather work on a white roof! (At least in Houston in the summer)!



          Robert Johnston





          -----Original Message-----
          From: Gary Beck [mailto:eco@...]
          Sent: Thursday, January 06, 2005 9:55 AM
          To: hreg@yahoogroups.com
          Subject: RE: Oh Politics! RE: [hreg] crash science initiative for
          alternative energy and conservation



          Incredible breakthoughs or not, one thing I have to point out is that
          solar cells should not be thought of as free or even renewable. The
          energy they capture is not free. They make electricity by capturing
          energy that is otherwise reflected back into space. All this captured
          energy will be released as sensable heat.



          The other point is that every solar cell I have ever seen is very dark
          color and that on a sunny day I assume you can fry and egg on them
          during operation. And they would remain warm for a few extra hours each
          night. Sounds like a hot city that has 1/2 of the area of every roof
          covered in in solar cells.



          This vision of a 'solar roof on every house' is the opposite of
          significant eco design efforts to try to cool cities by adopting
          building specifications changing commercial roof colors to white and
          residential roofs to very light shingles (plus a cooler roof means
          cooler living working space). Or better yet like USGBC-LEED and other
          efforts that support 'green' garden roof on new commerical buildings.



          What is the best approach to satisfy both concerns? Is there a light
          colored solar cell? Any one have a design for a solar cell garden roof?



          Gary Beck

          Eco-Holdings LLC



          I read ocasionally Scientific American, Discovery, Science etc. - they
          are great for 'what if' and 'think about this' , but not very good
          predictors at all. What were they saying about fuel cells 10 or 20 years
          ago? My son get Popular Science - a recent article is called "Hydrogen's
          Bomb - Decoding the Hype". My favorite recent new science release? The
          spinach plant that is designed to generate electricity (no joke) (here's
          a joke: It is a good thing since will require more candle lit dinners -
          cause after you finish your salad it's light out!)

          -----Original Message-----
          From: Roxanne Boyer [mailto:rox1@...]
          Sent: Tuesday, January 04, 2005 10:20 PM
          To: hreg@yahoogroups.com
          Subject: Re: Oh Politics! RE: [hreg] crash science initiative for
          alternative energy and conservation

          Mr. Malone,

          I quite dissagree with you on many of these issues, and so do most
          scientists. Read any of the articles today on energy in Scientific
          American, Physics Today, Discovery, Science, .... and you will find that
          our current oil consumption trends can only be sustained to about 2050,
          plus or minus 20 years. Renewable energy is growing exponencially.
          Europe is aiming for 20% renewables by 2020. I believe many of the US
          States already have similar goals and many more will join in as time
          goes on. There will be a change within the next lifespan.



          Even the "Oil" companies realize this and have published reports that
          say so. They are starting to call themselves "Energy" companies and
          investing quite heavily in renewable energy. See Shell Solar, Shell
          Wind, Shell Renewables, BP Solar, GE Solar, GE Wind, for example. And
          if the oil companies don't lead, the electronics companies will. Sharp
          is already the leading manufacturer of solar cells.



          I don't know how you did your math about not enough solar energy in New
          Jersey (is that the state with the highest energy to land ratio and the
          least sunny state?). But the math I have done shows that I can supply
          all of my Houston household electrical needs (averaged) by covering half
          of my roof with solar panels. No breakthrough technology needed; it
          already exists. If you trend retail electric prices and solar PV
          prices, you will see the cost cross in the year 2025 - then it will be
          more economical to buy PV than grid electricity!



          If you read up on the technical progress of photoelectrics, you will see
          incredible breakthroughs in the last 10 years. Right now, solar cells
          are expensive because production can not keep up with demand. And new
          record breaking production facillities are being opened each year.



          If you want a "heart felt" change, read the July-August issue of
          Renewable Energy World each year and see the growth of RE for yourself.
          It is amazing. Maybe we can discuss some of the facts at the next HREG
          meeting, Sunday, 2:00pm, Jan 30th at TSU.

          Sincerely,

          Chris





          ----- Original Message -----

          From: J. <mailto:JPMALONE@...> P. Malone

          To: hreg@yahoogroups.com

          Sent: Monday, January 03, 2005 8:43 PM

          Subject: RE: Oh Politics! RE: [hreg] crash science initiative for
          alternative energy and conservation





          All this discussion is interesting and heart felt. The following is not
          intended as a rant, but to put our problem in perspective.



          Our government, both parties, is so tied to big oil money, .

          It would take solar panels covering every square inch of the state of
          New Jersey just to equal the energy used in New Jersey. So the size of
          the oil dependency is almost beyond our reason.



          A breakthrough, one not foreseeable by current science is most likely
          the only hope in the US. Outside the US there may be some help because
          of the different mind set of the non US-Oil cartel.



          China is graduating more engineers & scientists each year than the US
          graduates all college students of all degree fields. China has a
          massive energy problem. They also have a growing economy that it partly
          controlled & partly free market. As they inevitably pass the US number
          of educated citizens (check out our schools systems if you doubt this)
          and the controlling government forces capital & research in to
          alternative energy research because of their vast needs and lack of
          resources they may turn this thing around.



          I hope I live long enough to see the beginning.

          In the interim, conservation, voting, getting activity in politics may
          be the only drop in the bucket we have. I hope I'm wrong.





          J. Patrick Malone



          -----Original Message-----
          From: Robert Johnston [mailto:junk1@...]
          Sent: Monday, January 03, 2005 7:36 PM
          To: hreg@yahoogroups.com
          Subject: RE: Oh Politics! RE: [hreg] crash science initiative for
          alternative energy and conservation








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