Tech + Engineering

23
Apr

Another Approach to Efficient Solar Power

Mike Orcutt, reporting for Technology Review:

Solar panels on the market today consist of cells made from a single semiconducting material, usually silicon. Since the material absorbs only a narrow band of the solar spectrum, much of sunlight’s energy is lost as heat: these panels typically convert less than 20 percent of that energy into electricity. But the device that ­Atwater and his colleagues have in mind would have an efficiency of at least 50 percent. It would use a design that efficiently splits sunlight, as a prism does, into six to eight component wavelengths—each one of which produces a different color of light. Each color would then be dispersed to a cell made of a semiconductor that can absorb it.