PG&E wants to store wind, solar energy- SFGate.com
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In a rural corner of Kern County, PG&E plans to build a facility that would use energy from renewable power plants to compress air and pump it into an underground reservoir. The pressurized air would later be fed into a turbine to generate electricity.
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PG&E's project would take wind power generated at night - when the winds in California blow their hardest - and use it to store compressed air in a formation of porous rock. During the day, when the winds die down, the facility could generate as much as 300 megawatts for up to 10 hours. A megawatt is enough to power roughly 750 homes at any given moment.
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