Loading ...
Sorry, an error occurred while loading the content.

2886RE: Oh Politics! RE: [hreg] crash science initiative for alternative energy and conservation

Expand Messages
  • Richard D. Kelley
    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.



      ----- 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


      Yahoo! Groups Links

      * To visit your group on the web, go to:

      * To unsubscribe from this group, send an email to:

      * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
      Service <http://docs.yahoo.com/info/terms/> .
    • Show all 18 messages in this topic