CMS Energy Corporation operates as an energy company primarily in Michigan. The company operates through three segments: Electric Utility; Gas Utility; and Enterprises. The Electric Utility segment is involved in the generation, purchase, transmission, distribution, and sale of electricity. This segment generates electricity through coal, wind, gas, renewable energy, oil, and nuclear sources. Its distribution system comprises 208 miles of high-voltage distribution overhead lines; 4 miles of high-voltage distribution underground lines; 4,428 miles of high-voltage distribution overhead lines; 19 miles of high-voltage distribution underground lines; 82,474 miles of electric distribution overhead lines; 9,395 miles of underground distribution lines; 1,093 substations; and 3 battery facilities. The Gas Utility segment engages in the purchase, transmission, storage, distribution, and sale of natural gas, which includes 2,392 miles of transmission lines; 15 gas storage fields; 28,065 miles of distribution mains; and 8 compressor stations. The Enterprises segment is involved in the independent power production and marketing, including the development and operation of renewable generation. It serves 1.9 million electric and 1.8 million gas customers, including residential, commercial, and diversified industrial customers. The company was incorporated in 1987 and is headquartered in Jackson, Michigan.