A heliostat is a special mirror with a guidance device that can keep sunlight reflected toward the same target all day without straying off-target. It is just a mirror but you need to keep it trained on the same spot for it to work. It is a bit like... Read More
Got some extra cans sitting around? This PF innovator did, so he made a DIY solar heater. Items that would’ve gone to waste, such as recycled beer cans, are put to good use and become part of a solar home heater!
The George Washington University
How much carbon do all those music videos and lolcats produce? Turns out it's quite a lot. Watch