The County Commission of Gregory County, S.D., filed a July 3 application with the Federal Energy Regulatory Commission for a preliminary permit on the 1,200-MW (net) Gregory County Energy Project, a pumped storage facility on the Missouri River.
The application, from consultant Schulte Associates LLC, said this is one of the prime sites in the western U.S. for a pumped storage project. The idea is to integrate this project with intermittent wind power in the region, evening out the power output in the region.
A preliminary permit gives the applicant an exclusive right to explore the feasibility of a project, with a license application at FERC to follow if the decision is to further develop the project. A prior preliminary permit on this project expired on June 30.
The upper reservoir for this project would be on the Missouri Plateau, about 700 feet above Lake Francis Case on the Missouri River, which would form the lower reservoir. The project would include four 300-MW (net) turbines and a 20-mile, 345-kV power line that would interconnect with existing transmission for the Fort Randall Generating Station.
Projected output for the Gregory County Energy Project is 3,120,000 MWh/year. The hydro project could supply power into the Western Area Power Administration, Midcontinent Independent System Operator and Southwest Power Pool regions.