Oglethorpe Power Corporation is a medium-sized electric utility in Georgia, United States. Formed in 1974, Ogelthorpe is a not-for-profit cooperative owned by the 38 electric membership corporations that it serves. The utility's headquarters are in Tucker, Georgia. It is the largest power supply cooperative in the United States based upon assets and annual kilowatt-hour sales. The utility's service area covers 65 percent of the state of Georgia. However, Georgia Power is the largest electricity supplier in the state. Ogelthorpe co-own several of its plants with Georgia Power and the Municipal Electric Authority of Georgia. As of 2009, the utility has an annual revenue of $1.2 billion and assets of over $9 billion. In 1997, Ogelthorpe restructured into three separate, but interrelated, cooperatives. Oglethorpe Power Corporation handles electricity generation, Georgia Transmission Corporation owns and operates the transmission lines and substations and Georgia System Operations Corporation provides system and administrative support.
As of 2009[update], Oglethorpe's power plants had a combined capacity of 5,790 megawatts. About 23% of the capacity is coal, 46% natural gas, 19% nuclear and 12% hydroelectric power. It owns 817 megawatts of the 1,095-megawatt Rocky Mountain Hydroelectric Plant, a pure pumped-storage hydroelectric plant that stores energy during periods of low electricity demand and produces electricity during periods of high demand. The utility's nuclear power comes from its partial ownership of the Edwin I. Hatch Nuclear Generating Station and the Alvin W. Vogtle Electric Generating Plant. It has partial ownership of two coal plants and full ownership of a combined cycle power plant and several gas turbine power plants.