The U.S. Department of Energy has announced a new solar cell that can convert more than 40% of sunlight into electricity. The cell, made by Boeing-Spectrolab, uses mirrors and prisms to boost the sunlight going into the cell. The DOE says the cells could be sold for $3 per watt and make electricity for 8 to 10 cents per KW/hour.
Regular solar cells are approximately 15 percent efficient because they convert regular sunlight. Concentrator cells, like this new breakthrough cell, use relatively cheaper mirrors and prisms to focus sunlight on the more expensive gallium-arsenide portion of the cell.
Spectrolab's new cell isn't too surprising to us because we interviewed company executives back in October when we toured their Sylmar solar cell factory. Company officials predicted that solar cells could eventually reach 45% efficiency using current technology.