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Let's Move On, From a Newcommer!

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  • John Hornsby
    MessageIs this a debate? There is no question that renewable energy is the only answer to the What happens when we run out of oil? question. Fuel cells,
    Message 1 of 1 , Jan 7, 2005
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      Is this a debate? There is no question that renewable energy is the only answer to the "What happens when we run out of oil?" question. Fuel cells, solar, wind and unused methane - these items already exist, in an abundance that we cannot even imagine. No sense in arguing the use-full-ness of any one of these energy sources. Honestly, if we could harness a 4-year-old child's energy from sun-up to sun-down, would anyone question? Come on, let's get back to figuring out how to make the things that are better for us a little cheaper, easier to obtain, and turn them into more "common knowledge". If I can help, I am going to! I don't care what color the panels are, or how many sq. ft. of land we need to power the state of Texas - I am, however interested in the CO2 emissions saved by taking 1 single house off of the "grid". I am interested in the rapidly rising number of business owners that see their power usage as a deficit to our planet. Can we focus on these issues?
      ----- Original Message -----
      Sent: Friday, January 07, 2005 3:57 PM
      Subject: RE: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

      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.





      ----- 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



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