Low Cost Solar Collector

Discussion in 'Off Grid Living' started by Ardent Listener, Dec 24, 2006.

  1. Ardent Listener

    Ardent Listener Monkey+++

    Solar Collector
    <HR style="COLOR: #d1d1e1" SIZE=1><!-- HEAD/SUBHEAD -->[FONT=Helvetica,Arial]An Innovative, Low-cost, Efficient Solar Collector[/FONT]
    <!-- SUBHEAD -->[FONT=Times,New Times]Can a metal dish convert the sun's energy to electricity more efficiently than photovoltaics?[/FONT]
    <!-- END header Table -->
    <!-- START Main Table --><TABLE cellSpacing=0 cellPadding=0 width=580 border=0><TBODY><TR vAlign=top><TD width=15></TD><TD vAlign=top width=170><!--CAPTION table STARTS--><TABLE cellSpacing=0 cellPadding=0 width=170 border=0><TBODY><TR vAlign=top><TD width=170>[​IMG]</TD></TR><TR vAlign=top><TD width=170 height=3></TD></TR><TR vAlign=top><TD width=170>[FONT=Helvetica,Arial]ABOUT 22% of incident solar energy is converted into electricity by a helium-filled Stirling engine and generator
    [/FONT]</TD></TR><TR vAlign=top><TD height=30></TD></TR></TBODY></TABLE><!--CAPTION table ENDS--><TD width=15><!--CHANGE dateline tag/ADD BOLD Lead-in copy-->.</TD><TD width=360>[FONT=Times,New Times]Nickel magazine, Mar. 00 -- What is the best way to improve the living standards of people in the developing world? Some say: by devising a low-cost, sustainable way to generate electricity. This would significantly reduce demands on the natural environment by replacing the need to burn charcoal, kerosene or dung.

    Considering that most developing countries are in equatorial regions, where solar radiation is at its most intense, solar collectors might just be the answer.

    Such was the reasoning employed by Germany-based Schlaich Bergermann und Partner (SBP) when it devised a way to construct rigid, lightweight parabolic solar collectors made of thin (0.28-millimetre) sheets of stainless steel (S30400), containing 8% nickel.

    Coupled with a Stirling engine and a generator, these collectors, which the company has dubbed the "Dish-Stirling System," can produce 10 kilowatts of electricity. Moreover, they can do so at a cost much lower than that incurred by the best photovoltaic systems (which convert solar energy more directly into electricity).

    Designers welded a thin sheet of stainless to a cylindrical housing ring 8.5 metres in diameter, ensuring that the dish is rigid and lightweight. The front surface of the metal membrane was deformed plastically into a parabaloid by applying air pressure from inside the housing and water ballast from the outside.

    To keep the dish pointed directly at the sun during the course of the day, a tracking system is used. Six demonstration collectors are running smoothly in Spain.
  2. Ardent Listener

    Ardent Listener Monkey+++

    This was contained in a reply to my post at the GIM site. I thought it might interest some of you. A.L.

    <HR style="COLOR: #d1d1e1" SIZE=1>

    Gamma design, stirling heat engine. More than likely they're using a liner design instead.
    <FIELDSET class=fieldset><LEGEND>Attached Thumbnails</LEGEND>[​IMG]
    </FIELDSET> <FIELDSET class=fieldset><LEGEND>Attached Images</LEGEND>[​IMG]
  3. melbo

    melbo Hunter Gatherer Administrator Founding Member

    If you do some searching on stirling you can find another company playing around with this as well. Looks pretty promising.
  4. Blackjack

    Blackjack Monkey+++

    Oh Heck yah man, stirling engines rock! I've been reading about 'em and hoping they'd take hold for a while now.

    Check Out http://en.wikipedia.org/wiki/Stirling_engine

    At the bottom of the page are manufacturers of all kinds of stirling engine generators and stuff..... combined heat and power, even a simple fan you sit on top of your wood stove to circulate air without electric.

    Here's the little fan. http://www.thermalengines.com/
  5. ghrit

    ghrit Bad company Administrator Founding Member

    Way, way more than one outfit is meddling with the stirling cycle. Very efficient, but somewhat difficult to control. It is either all on or all off, output is not steady, unless the load is stable. At least that is what I've seen in very small experimental units. Not all the problems have been solved, but the theory works, and is nearly developed to practical. The big BUT is that none I know of are commercialized at a level high enough to get out of the toy catagory. Might be able to build one --.
  6. Blackjack

    Blackjack Monkey+++

    STM's got it done!

    55 kw combined heat and power for commercial/industrial applications.
  7. ghrit

    ghrit Bad company Administrator Founding Member

    Now maybe we are getting somewhere. Bookmarked for later reading.
  8. BigUglyOne

    BigUglyOne Monkey+++ Founding Member

  9. ghrit

    ghrit Bad company Administrator Founding Member

    Now, if they come up with something between a toy and 55KW, we might have a closer look. I have a sneaking suspicion that the big ones are so much more efficient than (say) 10KW that the practicality of smaller machines is limited.
  10. melbo

    melbo Hunter Gatherer Administrator Founding Member

survivalmonkey SSL seal        survivalmonkey.com warrant canary