ALBUQUERQUE, N.M. — Solar Two, a large pilot solar power plant capable of producing 10 megawatts of electricity, was dedicated today in the Mojave Desert near Barstow, Calif. Engineers at Sandia National Laboratories here played a key role in developing this innovative solar technology.
The plant produces enough power to supply 10,000 homes, and today’s ceremony officially connects it to the utility grid in southern California. Department of Energy Secretary Hazel O’Leary presided over the dedication ceremony. Many Sandia engineers who worked on the project and Sandia upper management were on hand. The project is sponsored by the Solar Two Consortium, a group of 10 organizations led by Southern California Edison Company, in partnership with the Department of Energy.
The unique feature of Solar Two is its use of molten salt to capture and store the sun’s heat. Sandia has the technical lead in developing molten-salt technology for solar plants and provided the technical expertise required for Solar Two. These solar plants operate by using large, sun-tracking mirrors to concentrate sunlight on a receiver that sits atop a tower. The concentrated sunlight heats the molten salt as it flows through the receiver. The very hot salt is then piped away, stored, and used when needed to produce steam to drive a turbine/generator that produces electricity. The system is capable of operating smoothly through intermittent clouds and can continue generating electricity long into the night.
In contrast to Solar Two, its predecessor Solar One generated steam directly from water in its receiver. Although Solar One operated successfully from 1982 to 1986, its direct steam system suffered from low efficiencies in energy storage and interrupted operation resulting from passing clouds. The molten-salt approach overcomes these difficulties.
Sandia, under DOE’s auspices, has been developing solar central receiver technology since the 1970s. Sandia conducted large-scale experiments on the components needed in a molten-salt system at its Central Receiver Test Facility here and developed much of the knowledge necessary to spur confidence in molten-salt solar power towers. This confidence led to the Solar Two project becoming a reality. Sandia will continue to support the project through the remaining phases of startup, test and evaluation, and operation.
Speaking from his office in Washington, D.C., Gary Burch, director of the Solar Thermal and Biomass Power Division in the Department of Energy praised Sandia’s role in the Solar Two project “Sandia’s leadership and expertise in power tower technology have been instrumental in making the Solar Two project a success,” he said. “Sandia played a key role in providing assistance by transferring molten-salt technology to the project, by leading the Technical Advisory Committee which oversaw all technical aspects of the project, and by supporting the design, construction, and startup of the plant through the outstanding efforts of its staff.”
The $48.5 million cost of Solar Two’s design, construction, and three-year operation is equally shared by the Department of Energy and the consortium. In addition to Southern California Edison, the second largest electric utility in the nation, the other project participants are: Arizona Public Service, based in Phoenix; Bechtel Corp., based in San Francisco; California Energy Commission, based in Sacramento; Electric Power Research Institute, in Palo Alto, Calif.; Idaho Power Co., based in Boise; Los Angeles Department of Water and Power; PacifiCorp, in Portland, Ore.; Sacramento Municipal Utility District; and Salt River Project, based in Tempe, Ariz.