BrightSource Energy today disclosed plans to build a 750-megawatt solar power plant in California, which would be its third and largest utility-scale project.
The company said that the Rio Mesa Solar Electric Generating Facility will use its solar tower technology, where a field of mirrors reflects light onto a tower to create steam that drives a turbine to generate electricity. The project would generate enough electricity to power more than 300,000 homes, BrightSource said.
The plan calls for installing three towers able to generate 250 megawatts each (before accounting for the energy consumed by their operation).
BrightSource earlier this year began construction of the Ivanpah Solar power project, where the company had to cut back on the amount of land it planned to use and monitor the health of the endangered desert tortoise at the location. The Rio Mesa proposal calls for using a taller tower, which will allow project developers to place its sun-tracking mirrors, called heliostats, more densely onto the available land.
The location is in Riverside County, where most of the land had been owned by the Metropolitan Water District and some by the U.S. Bureau of Land Management. The site is close to high-voltage transmission lines, which is a crucial consideration, and had been used as military training grounds during World War II.
There are a number of utility-scale solar power plants now being planned or constructed. Because of the falling costs of solar photovoltaic panels, a few projects have abandoned solar thermal technologies in favor of PV.
BrightSource Energy's solar tower technology is different than traditional solar thermal systems where mirrored troughs generate heat for a steam generator.
The company said the Rio Mesa plant would use 33 percent less land than a comparable solar photovoltaic power plant or a solar thermal plant with mirrored troughs. By using air cooling to turn steam back into water, BrightSource said, the plant's water use will be less than 10 percent of that of competing technologies.
Demand for these utility-scale projects is being driven by California's renewable energy mandate, which requires utilities to get 33 percent of electricity from renewable sources by 2020.
BrightSource said it expects the Rio Mesa project to be completed by 2016.