Or is this a $737 million taxpayer disaster?
The New York Times reports,
… The Energy Department seems to agree: in September it gave SolarReserve a $737 million loan guarantee for its project in Nevada. The plant will generate 110 megawatts at peak and store enough heat to run for eight to 10 hours when the sun is not shining…
Technical details of the SolarReserve and BrightSource plants vary slightly, but both will use thousands of computer-operated poster-size mirrors aiming sunlight at a tower that absorbs it as heat.
SolarReserve absorbs the heat in molten salt, which can be used immediately to boil water, generating steam that turns a conventional turbine and generator. Hot salt can also be used to retain the heat for many hours for later use. BrightSource heats water that can be used immediately as steam or to heat salt for storage.
The plants rely on salt because it can store far more heat than water can. But once molten, it must be kept that way or it will freeze to a solid in part of the plant where it will be difficult to melt again. “You’ve made a commitment to those salt molecules,” said John Woolard, the chief executive of BrightSource.
The technology is not complicated, but the economics are.
The simplest, least expensive path for solar thermal is to turn the heat into electricity immediately. But the companies are a bit like the farmer who harvests the grain and stores it in a silo rather than shipping it straight to market on the expectation that prices will be higher later. They are betting that in revenue terms, the hour at which the energy is delivered will be more important than the amount generated…