Molten salt storage could store the solar energy and generate steam to drive a turbine for the hours of non sun generation. The first plant using this technology is being built is Spain.

If the one about the size of England were covered with solar thermal mirrors (which heat up fluid to drive a turbine), it could supply all the world's electricity needs, he said.

BrightSource's system, like other "solar thermal" technologies, concentrates the sun's heat to drive turbines; and the high-performance steam turbines it relies on are big.