Todd Woody at Forbes has a post on a new, dispatchable solar thermal power plant planned for Nevada - Obama administration grants $737 million for a 24/7 solar power plant
The Obama administration on Thursday offered Santa Monica solar startup SolarReserve a $737 million loan guarantee to build a 110-megawatt solar thermal power plant in Nevada that can generate electricity 24 hours a day.
That’s the holy grail for intermittent sources of carbon-free energy such as solar and wind and the SolarReserve loan guarantee is a sign that the United States Department of Energy is willing to gamble on a technology untested on a commercial scale.
SolarReserve literally was founded by rocket scientists from United Technologies’ Rocketdyne division in 2007 and licenses its molten salt technology.
Like rival BrightSource Energy, SolarReserve will deploy massive arrays of mirrors called heliostats around a very tall tower – in this case, one that tops 640 feet – with a boiler attached. BrightSource’s heliostats focus the sun on a water-filled boiler to create steam that drives an electricity-generating turbine.
SolarReserve fills its boiler with millions of gallons of molten salt. Some 17,500 heliostats heat the salt to 1,050 degrees Fahrenheit. The liquefied salt then generates steam to drive the turbine before returning to the receiver. The salt retains heat that can be released at night or when the sun is not shining to continously to produce power.
“This solar technology is a genuine alternative to baseload coal, nuclear or natural gas burning electricity generation facilities," Kevin Smith, SolarReserve’s chief executive, said in a statement.
The Nevada project, called the Crescent Dunes Solar Energy Project, will be built on federal land in Tonopah, Nev., about 220 miles northwest of Las Vegas. SolarReserve said the molten salt can extend Crescent Dunes’ daily operation by 10 to 12 hours and the project can power 75,000 homes at peak output. Whether the utility that has contracted to buy the Crescent Dunes’ electricity, NV Energy, will want the plant to actually run around the clock depends on how it balances demands placed on the grid.
SolarReserve, which also has a license to build a 150-megawatt solar farm in the Southern California desert, is counting on the ability to provide carbon-free power when the sun isn’t shining as a competitive advantage. Rivals are also offering solar storage – Abengoa’s federally funded Solana solar trough power plant in Arizona, for instance, will feature up to seven hours’ storage.