Stirling Engine powered Solar Plant planned in California

Southern California Edison and San Diego Gas & Electric are working with Stirling Energy Systems. They plan to build a 300 MW and a 500 MW in California. These plants will work with Stirling Engines, and so they will provide higher efficiency compared to photovoltaics. I hope, that these plants will work, because, if they do, they provide a lot of energy without damaging the environment - and it seems, they could even work economically.