Phoenix firm to build huge solar farm

This solar instalation is expected to produce electricity at a cost similar to electricity from fossil fuels -- a huge breakthrough in large scale solar electricity.
Phoenix firm to build huge solar farm - Phoenix - MSNBC.com:

'This is a breakthrough event for solar energy,' said Stirling Chief Executive Bruce Osborn. 'This is the world's most efficient solar technology.'
Stirling's concentrated solar dish -- unlike photovoltaic panels that collect sunlight on a much smaller scale -- harnesses heat from the sun with 82 mirrors and reflects it toward a series of hydrogen-filled tubes that expand when heated. The expanding gas cycles back and forth from cold to hot, and its movement powers a piston that creates up to 25 kilowatts of power.