Howdy Joe, don't stop with IR, you want to absorb all wavelengths- there is more energy available in the visible/UV than the IR. Any flat black material will absorb all wavelengths (not counting high energy stuff like gamma rays). what you need is a material which not only absorbs, but also conducts the heat absorbed rather than radiating it away in the IR. (Wein's displacement)
Joe Street wrote: > Do you have any information on IR absorption of common black materials, > ie flat black paint types which are resonably good? I plan to do > something with it one day but would like to make something myself of > reasonable efficiency rather than buying a turnkey solution. > > Joe > > Hakan Falk wrote: >> Joe, >> >> In Israel you will see the same, but with efficient solar panels >> built together with an insulated storage. It is however an enormous >> difference in efficiency. The black cisterns have a very low >> efficiency and you can only collect some warm water at the end of >> sunny days. The main functionality of cisterns on the roof, is to >> give distribution pressure. It is also very large differences in the >> coloring methods, what is looking black to us, can have very >> different absorption factors. A Swedish company is the market leader >> in delivering the solar collection elements for solar panels. They >> deliver them in rolls of double black colored copper sheets. Before >> mounting they are cut to size and pressurized to form the space for >> water passage. Efficient solar panel construction was researched >> around 40 years ago in Almeria, Spain, a joint project between >> technical universities of Sweden and Spain. The Swedish part was >> managed by prof. Folke Petterson, KTH, who also used some simulation >> work with the energy transmission program that we have. >> >> Hakan >> >> At 00:40 28/04/2006, you wrote: >> >>> Almost every house and building has a big black cistern on the >>> roof. The are everywhere you look. >>> >>> Joe >>> >>> Hakan Falk wrote: >>> >>>> Joe, >>>> >>>> Yes, but Mexico it is a bit larger and more people than Israel and in >>>> total they do not have the same density, but last time was around 15 >>>> years ago and Israel the last time was around 6 years ago, China 5 >>>> years and Brazil last time was only 2 years ago. Time goes very fast. >>>> Still, I doubt it, considering that Israel is a export producer of >>>> thermal solar systems also. >>>> >>>> Hakan >>>> >>>> At 21:03 27/04/2006, you wrote: >>>> >>>> >>>> >>>> >>>>> Hakan Falk wrote: >>>>> >>>>> >>>>> >>>>>> Zeke, >>>>>> >>>>>> Solar thermal hot water is the cheapest and most efficient solar use, >>>>>> I do not understand that the use is so low. This except Israel, where >>>>>> you can see solar for hot water on almost every house. . >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>> snip >>>>> >>>>> Ever been to Mexico? >>>>> >>>>> Joe >>>>> >>>>> >>>>> _______________________________________________ >>>>> Biofuel mailing list >>>>> <mailto:Biofuel@sustainablelists.org>Biofuel@sustainablelists.org >>>>> http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org >>>>> >>>>> Biofuel at Journey to Forever: >>>>> <http://journeytoforever.org/biofuel.html>http://journeytoforever.org/biofuel.html >>>>> >>>>> Search the combined Biofuel and Biofuels-biz list archives (50,000 >>>>> messages): >>>>> <http://www.mail-archive.com/biofuel@sustainablelists.org/>http://www.mail-archive.com/biofuel@sustainablelists.org/ >>>>> >>>>> >>>> >>>> >>>> _______________________________________________ >>>> Biofuel mailing list >>>> <mailto:Biofuel@sustainablelists.org>Biofuel@sustainablelists.org >>>> http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org >>>> >>>> Biofuel at Journey to Forever: >>>> <http://journeytoforever.org/biofuel.html>http://journeytoforever.org/biofuel.html >>>> >>>> Search the combined Biofuel and Biofuels-biz list archives (50,000 >>>> messages): >>>> <http://www.mail-archive.com/biofuel@sustainablelists.org/>http://www.mail-archive.com/biofuel@sustainablelists.org/ >>>> >>>> >>>> >>>> >>> _______________________________________________ >>> Biofuel mailing list >>> Biofuel@sustainablelists.org >>> http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org >>> >>> Biofuel at Journey to Forever: >>> http://journeytoforever.org/biofuel.html >>> >>> Search the combined Biofuel and Biofuels-biz list archives (50,000 >>> messages): >>> http://www.mail-archive.com/biofuel@sustainablelists.org/ >>> >> >> >> >> _______________________________________________ >> Biofuel mailing list >> Biofuel@sustainablelists.org >> http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org >> >> Biofuel at Journey to Forever: >> http://journeytoforever.org/biofuel.html >> >> Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): >> http://www.mail-archive.com/biofuel@sustainablelists.org/ >> >> >> > > ------------------------------------------------------------------------ > > _______________________________________________ > Biofuel mailing list > Biofuel@sustainablelists.org > http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): > http://www.mail-archive.com/biofuel@sustainablelists.org/ > -- Bob Allen http://ozarker.org/bob "Science is what we have learned about how to keep from fooling ourselves" — Richard Feynman _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
