CMS Energy Corporation, operates as an energy company primarily in Michigan. It operates in three segments: Electric Utility, Gas Utility, and Enterprises. The Electric Utility segment engages in the generation, purchase, distribution, and sale of electricity. The Gas Utility segment involves in the purchase, transmission, storage, distribution, and sale of natural gas. The Enterprises…More segment engages in independent power production and marketing. This segment owns power generation facilities fueled mostly by natural gas and biomass.