Edward Hyatt (Oroville) Underground Power Plant

Edward Hyatt (Orville) Power Plant is the largest underground pump-generating installation in the United States. The plant's 3 turbines and 3 pump-turbines have an installed capacity of 644 Mw. When operating along with the adjoining Thermalito powerplant 725 dependable Mw are produced, yielding $16,000,000 in power revenues annually. Less than 5 yr after initial construction on Edward Hyatt Power Plant began, benefits in the form of power revenues and electrical energy began to accrue to the State of California. The final design for the underground location was made after detailed analysis of geologic conditions, construction techniques, equipment layout, operation requirements, and the powerplant's relationship to Oroville Dam and other pump-storage features of the multipurpose Oroville disciplines complex. Experts from the fields of rock mechanics, the various engineering disciplines, architecture, and economics, plus equipment manufacturers and construction companies, all played a major role in the construction and realization of the operational status of the Edward Hyatt Power Plant.