Technology.am (Aug. 7, 2009) — eSolar has unveiled its 5 MW Sierra SunTower solar power plant located in southern California’s Antelope Valley.
This plant is made up of 24,000 silver-bright mirrors, which have been positioned in the Valley to reflect light on two 50-meter-tall towers.
The concentrated light coming from mirrors heated steam in those towers to turn a turbine. This is the first “power towers” in the U.S. to convert the sun’s heat into electricity for commercial use.
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.
The 5 MW energy produced by this power plant is enough to power roughly 4,000 local homes at full capacity—and provide the modular blueprint for larger plants in California and New Mexico.
The key to eSolar’s design are the mirrors—known as heliostats in the concentrating–solar power industry. By precisely calibrating the mirrors with computer algorithms driving shoe box–size motors, eSolar can build its sunlight-harvesting power plants with many more small, flat mirrors, roughly one square meter in size.
It is estimated that the entire state of California’s peak electricity demand could be generated from an eSolar field of 65 square kilometers. That electricity would cost no more than 13 cents per kilowatt-hour.
The company has paired with NRG Energy, Inc., to develop two full-scale power plants totalling 92 megawatts in New Mexico as well as 337 megawatts of further power towers in California.