Atlas Copco Supplies Equipment For Geothermal Power Plants
Atlas Copco Gas and Process expander generators have been fully commissioned and according to the company, are capable of producing enough energy to power a medium-sized city. Six turboexpanders are installed in the Enel Green Power’s Stillwater and Salt Wells geothermal power plants near Fallon, Nevada, U.S.A. The two geothermal plants have a total gross installed capacity of 65 MW, will generate more than 400 million kWh of electricity a year and avoid more than 300 000 tons of CO2 emissions.
The Atlas Copco expander generators were manufactured at Atlas Copco Mafi-Trench Company LLC (formerly Mafi-Trench Corporation) production facility located in Santa Maria, California, U.S.A. The large radial inflow turbines are capable of producing up to 15 MW per unit. The Stillwater and Salt Wells facilities utilize binary cycle technology that employs two fluids. The hot water extracted from the geothermal well is used to heat and vaporize a working fluid (isobutane in the case of Saltwells and Stillwater) that is completely contained in a closed loop.
The vaporized working fluid is expanded through the Atlas Copco turbines, which spin electric generators and produce electricity. The hot water is returned below ground and the isobutane leaving the turbine is condensed into liquid, which is then pumped up to high pressure. The isobutane is re-heated and re-vaporized, expanded through the turbine, condensed into liquid, and re-pressurized, always remaining within the closed circuit, ensuring no emissions.
Construction on the power plants began in 2007 and ENEL fully commissioned the plants in April 2009 with an inauguration ceremony. Enel Green Power, established in December 2008, is the Enel Group’s new company dedicated to the development of renewable energy sources. Headquartered in Italy, Enel is Italy’s largest power company, and Europe’s second-ranked utility by installed capacity.
For more information: www.atlascopco.com