In doing research for this article I have run across some great green products but never one like this. Can you imagine getting electrical power from balloons? This is what a Cool Earth out of Livermore, California has done when it designed the next generation of solar collectors. The basic concept hasn't changed; convert sunlight into electric power using solar cells; but the packaging has changed, and this is where balloon design is unique.
One side of the balloon is made from reflective silver Mylar plastic. With the other half is clear to let sunlight in. The silver material is parabolic-shaped to concentrate the sunlight on to a single point. That point is the solar cell package that is placed on an arm at the precise point of maximum light concentration.
The balloon has a simple circular metal frame that is used to hold the Mylar in the proper shape. An arm extends from the ring to the top center of the orb. This holds the solar cells that produce the electricity. The cells are cooled by water to dissipate the heat concentrated on the solar cells.
The balloon's design will concentrate the sunlight 300 to 400 times better than traditional roof mounted solar panels. By design, this reduces the cost of each balloon and greatly increases electrical output per cubic inch of solar cell material. This means that cost of the electricity produced will be on par with current natural gas peaker power plants.
When operational the balloon will produce about 1kw of power. With the average house consuming around 3.5 kw it would only require a 20 sq ft area foorprint. But alas the company is only looking at producing this design for local utility companies and large business.
Some of the more daunting aspects of any of the green products i have looked at is cost. When researching renewable solar power it is amazing how simple this design is and how much cost reduction has been applied. If this product is every mass produced the cost per watt will drop significantly and maybe to a level where its cost is on par with coal producing power plants.