The new facility is the largest of its type to be built in the world since 1991, although a 1-megawatt solar thermal plant was built in Arizona last year. Like its predecessors, Nevada Solar One relies on long lines of trough-shaped parabolic mirrors that focus the sun's heat onto a receiver tube filled with a heat transfer fluid, such as oil. The fluid is heated to about 750 degrees Fahrenheit and is then used to produce steam, which drives a turbine and generator to produce electricity. The Nevada Solar One plant consists of 47 miles of parabolic mirrors arranged in a grid and will produce enough power to supply 15,000 average U.S. homes. See the June 7th press release by selecting "English" in the lower left corner of the Acciona Energy Web site.
A number of other companies plan to employ parabolic trough technology in the United States, primarily in California. In early April, the California Energy Commission (CEC) announced that it is reviewing the license application for a proposed 563-megawatt power plant near Victorville, about 60 miles northeast of Los Angeles. The proposed facility would produce 50 megawatts of power from parabolic troughs but would generate most of its power from natural gas. In March, Solel Solar Systems, Ltd., an Israeli company, announced a deal to sell thousands of parabolic trough systems to FPL Energy, the co-owner and operator of seven large plants in California's Mojave desert. Solel has a previous deal with FPL Energy to upgrade the receivers at the existing plants, while the new deal will allow for additional power production at those plants. In addition, DOE's Sandia National Laboratories has developed a new device to help align the mirrors of parabolic troughs. The device could help parabolic trough plants generate more power. See the press releases from the CEC, Solel (PDF 28 KB) and Sandia. Download Adobe Reader.
Meanwhile, the Spanish company Solúcar Energía, S.A. is developing two solar thermal power plants near Seville, Spain, that employ another technology, called a power tower. The facilities will consist of a large field of heliostats—flat mirrors on sun-tracking mounts—that focus the sun's heat onto a receiver mounted on a central tower. A heat transfer fluid is pumped through the receiver and used to generate power, just as in a parabolic trough plant. The first power plant, PS10, is 11.02 megawatts in capacity and is essentially complete, with startup scheduled for later this year. Site preparation for the second plant, the 20-megawatt PS20, began last October. The PS10 plant will be the first commercial solar power tower facility in the world. See the October 2006 and January 2007 press releases by selecting the U.S. flag symbol (for English) and then selecting "Newsroom" on the Solúcar Web site.
