Dual purpose water-electric solar panels
This little lamp appeared in my head: when you have a limited area (such as roofs) to mount solar panels on, wouldn’t it be great to have a dual-purpose light/heat collector solar panel? The upmost surface would be the photo-voltaic cells, and underneath you’d have the water channels for the primary water circuit. This wouldn’t hurt the efficiency of the photo-voltaic part, and a lot of the re-emited infrared “waste” energy could be absorved through the water for water heating and climatization, I’m sure the overall efficiency would be worth it.
I haven’t been able to find anything similar online, has anyone ever heard of it? (see update below) With the advancement of the production techniques and the subsequent lower costs, you could have whole houses/buildings covered in modular dual-purpose tiles like these.
Update (May 18th, 2008):
Reader Andreas Mühlmann has pointed out there’s already a product like I proposed, although there are some problems with the concept.
