14 DAY TRIAL // In case you've never heard of Spectrolab, you don't know what you've been missing. And this statement is no mistake. Because Spectrolab is one of the few producers in the world that actively deliver solar-cell arrays. And this time, they've come up with something entirely new.
40% of sunlight turned into electricity. Sounds really nice and it's made by Boeing-Spectrolab. The cell uses mirrors and prisms to over boost the sunlight that enters into the cell. The cells could be sold for $3 per watt and should produce electricity for 8 to 10 cents per KW/hour. Using a 40 % EE (energy efficient) cell, one centimeter square cell could produce almost 16W of power.
Concentrator cells (like this new 40% EE one) use relatively cheaper mirrors and prisms to focus sunlight on the more expensive gallium-arsenide portion of the cell and by that, they produce more than twice of the regular energy that comes out from non concentrated arrays (about 15% EE). Spectrolab officials predicted that solar cells could eventually reach 45% efficiency using current technology but the 45% limit will not be surpassed with gallium-arsenide cells.
Worldwide, the production of solar cells is sustained mostly by Japanese companies like Sharp and Kyocera, but American ones are trying hard to match the Japanese producers. Google's Nanosolar has planned a 500 MW capacity plant for the Silicon Valley area and Spectrolab engineers think they can deliver a 120 MW concentrated cells array. That may be an interesting thing but such projects generally take a lot of time and space and the resulted power doesn't justify the costs. One solution could be the deployment of large arrays in space but Spectrolab says that the EE factor will in fact be smaller than when using a similar array on earth because the light in space is harder to absorb.