CoolEarth, a company we've briefly covered before, has created an innovative way to harness the sun's energy. Instead of large expensive solar panels or costly concentrating mirrors, the company is using balloons made of metalized plastic films. Half of the balloon is transparent, letting the light in to be concentrated into a small high-efficiency solar panel by the concave interior. Each is 2 meters across and, depending on the source, estimates vary from 500 watt to 1 kilowatt. They are supported by cables, leaving the ground below clear and limiting environmental impact.
The company has just raised $21 million, and it says that "this is just the initial closing of the round, [it could be extended] over the next 60 days." The company closed a $1 million round of angel investing last June. Read on for more photos and details. . . www.treehugger.com/renewable-energy