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Stirling Engine Systems is building large dishes that concentrate the sun's rays to drive a mechanical engine. The company is under contract to build an array of dishes capable of generating 500 megawatts of electricity.
With rising electricity prices, traditional silicon-based solar photovoltaic panels are being used more widely. FedEx recently installed nearly 1 megawatt of local power generation at its Oakland, Calif., airport location.
PowerLight, which manufactures solar panels, is developing roofing tiles that can generate electricity. The company hopes to build partnerships with building companies.