U.S. solar supremacy got a bump today when eSolar, a Google-funded startup that makes Lego-like modular solar panels, turned on the first solar power tower in the country. The five-megawatt Sierra SunTower, located in Lancaster, California, is made up of 24,000 mirrors and two 160-foot towers.

ESolar's system works by using mirrors to concentrate rays from the sun onto water-filled receivers sitting atop the solar power towers. Steam from the tank turns a turbine, which then provides power directly to local utility Southern California Edison. The whole system uses GPS positioning to quickly align the mirrors to best capture sunlight. At full capacity, eSolar's system operates at 800 degrees Fahrenheit and produces 800 pounds of steam per square inch.

Traditional reflective trough technology uses expensive curved mirrors to heat oil in a tube, but eSolar claims that its steam-producing tower is much more efficient. At the plant's unveiling today, CEO Bill Gross even proclaimed that his system "offers the lowest cost solar project in history" and that it would take only 25 by 25 miles of eSolar's mirrors and towers to power all of California. The electricity is cheap, too--the system produces power below the retail rate of California power (13 cents per kilowatt hour).

We'll see how well the system works in the coming weeks, but eSolar already has more projects lined up. India's Acme group bought a license for eSolar's technology for $30 million, and NRG Energy paid $10 million for rights to build 500 megawatts of solar power towers in the U.S.

[Via Earth2Tech]

Related Stories:
The Solar Industry Gains Ground -- And Goes Global
Desertec: World's Largest Solar Pipeline Charges Ahead