One of Silicon Valley’s most ambitious alternative energy start-ups has lured a top executive from the US electricity generation industry as its chief executive – the latest sign of the Valley’s push to become a major force in “green” technologies.

Ausra, a solar power company backed earlier this month by $40m from venture capitalists Vinod Khosla and Kleiner Perkins Caufield and Byers, has set out to build utility-scale power plants using solar thermal technology. The idea uses mirrors to reflect sunlight and generate steam to turn a turbine, and enjoyed a brief boom in the 1980s but fell out of favour as energy prices fell.