SolarReserve Solar Thermal Plant To Use Molten Salt
SolarReserve receives approval to begin construction on Crescent Dunes, Nevada solar thermal plant
SolarReserve, a Santa Monica-based company, gained approval from the federal government in December of last year to begin construction on its Crescent Dunes project, a solar thermal plant that will employ molten salt rather than water in order to store the heat it generates. SolarReserve's solar thermal plant will be built in Nye County, Nevada, near the city of Tonopah. Construction is expected to begin by mid-2011.
At the proposed solar thermal plant, a field of individually mounted sun-tracking mirrors, called heliostats, will focus the sun's rays on a large tank situated on top of a 653-foot tower. At other solar thermal plants, such as those designed by eSolar and Brightsource Energy, this tank is filled with water, but at SolarReserve's proposed solar plant, the tank will be filled with molten salt. The mixture of sodium and potassium salts will be heated up to 1,050 degrees Fahrenheit and then pumped into a heat exchanger, where it will be used to power steam turbines and thereby generate electricity.
Because salt dissipates heat at a slower rate than water, SolarReserve's solar thermal plant will be more effective at storing energy than traditional solar thermal plants and will be able to supply energy to the grid for up to eight hours after the sun sets. The solar thermal plant will also be less weather-dependent, as passing clouds will not cause the molten salt to quickly lose energy. Concerns have been raised about this new technology, however, including whether the salt will form clumps or corrode pipes. It remains to be seen whether SolarReserve's solar thermal plant will be as viable in practice as it seems in theory.