Incorporated in 1961, Basin Electric Power Cooperative is one of the largest electric generation and transmission cooperatives in the United States. Located in Mandan, N.D., the firm provides power marketing and telecommunication services. Its service territories comprise 540,000 square miles in nine states. The cooperative caters to more than 2.8 million of electric consumers and operates approximately 4,424 megawatts (MW) of wholesale electric generating capacity. Basin Electric Power Cooperative maintains 2,178 miles of high-voltage transmission, serving 135 member systems.