The Gianelli Power Plant, also known as the San Luis Power Plant, is a
pumped-storage hydroelectric
Pumped-storage hydroelectricity (PSH), or pumped hydroelectric energy storage (PHES), is a type of hydroelectric energy storage used by electric power systems for load balancing. The method stores energy in the form of gravitational potential ...
plant that is at the base of the
San Luis Dam
San Luis Dam is a major earth-filled dam in Merced County, California, which forms San Luis Reservoir, the largest off-stream reservoir in the United States. The dam and reservoir are located in the Diablo Range to the east of Pacheco Pass and ab ...
in California. During the wet season, turbines pump water from the
O'Neill Forebay
O'Neill Forebay is a forebay to the San Luis Reservoir created by the construction of O'Neill Dam across San Luis Creek approximately west of Los Banos, California, United States, on the eastern slopes of the Pacific Coast Ranges of Merced Co ...
into the reservoir, then when needed during the irrigation season, water flows from the reservoir back through the turbines and generates electricity.
[http://www.energystorageexchange.org/projects/196] This is an unusual use of pumped storage where the intention is to capture irrigation water not to store power. Storage capacity delivers up to 298 hours of generation at full power.
References
Power stations in California
San Luis Obispo, California
Pumped-storage hydroelectric power stations in the United States
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