The Southern Company, through its subsidiaries, engages in the generation, transmission, and distribution of electricity. The company also develops, constructs, acquires, owns, and manages power generation assets, including renewable energy projects and sells electricity in the wholesale market; and distributes natural gas in Illinois, Georgia, Virginia, and Tennessee, as well as provides gas marketing services, gas distribution operations, and gas pipeline investments operations. In addition, it owns and operates nuclear, coal, hydro, cogeneration, solar, wind, battery storage, and fuel cell facilities. Further, the constructs, operates, and maintains approximately 77,900 miles of natural gas pipelines and 14 storage facilities with total capacity of 157 Bcf to provide natural gas to residential, commercial, and industrial customers. The company serves approximately 8.9 million electric and gas utility customers. Further, it develops distributed energy and resilience solutions; deploys microgrids for commercial, industrial, governmental, and utility customers; and offers digital wireless communications and fiber optics services. The Southern Company was incorporated in 1945 and is headquartered in Atlanta, Georgia.

Duke Energy Corporation, together with its subsidiaries, operates as an energy company in the United States. It operates through two segments: Electric Utilities and Infrastructure (EU&I), and Gas Utilities and Infrastructure (GU&I). The EU&I segment generates, transmits, distributes, and sells electricity in the Carolinas, Florida, and the Midwest. It generates electricity through coal, hydroelectric, natural gas, oil, solar and wind sources, renewables, and nuclear fuel. This segment also engages in the wholesale of electricity to municipalities, electric cooperative utilities, and load-serving entities. The GU&I segment distributes natural gas to residential, commercial, industrial, and power generation natural gas customers; and invests in pipeline transmission projects, renewable natural gas projects, and natural gas storage facilities. The company was formerly known as Duke Energy Holding Corp. and changed its name to Duke Energy Corporation in April 2006. Duke Energy Corporation was founded in 1904 and is headquartered in Charlotte, North Carolina.

Xcel Energy Inc., through its subsidiaries, engages in the generation, purchasing, transmission, distribution, and sale of electricity. It operates through Regulated Electric Utility, Regulated Natural Gas Utility, and All Other segments. The company generates electricity through wind, nuclear, hydroelectric, biomass, and solar energy sources, as well as coal, natural gas, oil, wood, and refuse-derived fuels. It also purchases, transports, distributes, and sells natural gas to retail customers, as well as transports customer-owned natural gas. In addition, the company develops and leases natural gas pipelines, and storage and compression facilities; and invests in rental housing projects and nonregulated assets, as well as procures equipment for the construction of renewable generation facilities. It serves residential, commercial, and industrial customers in the portions of Colorado, Michigan, Minnesota, New Mexico, North Dakota, South Dakota, Texas, and Wisconsin. The company was incorporated in 1909 and is headquartered in Minneapolis, Minnesota.

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.

DT Midstream, Inc., together with its subsidiaries, provides integrated natural gas services in the United States. The company operates through two segments, Pipeline and Gathering. The Pipeline segment owns and operates interstate and intrastate natural gas pipelines, storage systems, and natural gas gathering lateral pipelines. This segment also engages in the transportation and storage of natural gas for intermediate and end-user customers. The Gathering segment owns and operates gas gathering systems. This segment is involved in the collection of natural gas for delivery to plants for treating, to gathering pipelines for further gathering, or to pipelines for transportation; and provision of associated ancillary services, including compression, dehydration, gas treatment, water impoundment, water transportation, water disposal, and sand mining. It serves natural gas producers, local distribution companies, electric power generators, industrials, and national marketers. The company was incorporated in 2021 and is headquartered in Detroit, Michigan.

Consumers Energy Company operates as an electric and gas utility in Michigan. It is involved in the generation, purchase, transmission, distribution, and sale of electricity through coal, wind, gas, renewable energy, oil, and nuclear sources. The company also engages in the purchase, transmission, storage, distribution, and sale of natural gas. It serves residential, commercial, and diversified industrial customers. Consumers Energy Company was formerly known as Consumers Power Company and changed its name to Consumers Energy Company in 1997. The company was founded in 1886 and is based in Jackson, Michigan. Consumers Energy Company operates as a subsidiary of CMS Energy Corporation.

ALLETE, Inc. operates as an energy company. The company operates through Regulated Operations, ALLETE Clean Energy, and Corporate and Other segments. It generates electricity from coal-fired, biomass co-fired / natural gas, hydroelectric, wind, and solar. In addition, the company provides regulated utility electric services in northwestern Wisconsin to approximately 15,000 electric customers, 13,000 natural gas customers, and 10,000 water customers, as well as regulated utility electric services in northeastern Minnesota to approximately 150,000 retail customers and 14 non-affiliated municipal customers. Further, it owns and maintains electric transmission assets in Wisconsin, Michigan, Minnesota, and Illinois. Additionally, the company focuses on developing, acquiring, and operating clean and renewable energy projects; and owns and operates approximately 1,200 megawatts of wind energy generation facility, as well as involved in the coal mining operations in North Dakota; and real estate investment activities in Florida. It owns and operates 162 substations with a total capacity of 9,980 megavolt amperes. The company serves taconite mining, paper, pulp and secondary wood products, pipeline, and other industries. The company was formerly known as Minnesota Power, Inc. and changed its name to ALLETE, Inc. in May 2001. ALLETE, Inc. was incorporated in 1906 and is headquartered in Duluth, Minnesota.

TransAlta Corporation engages in the development, production, and sale of electric energy. It operates through Hydro, Wind and Solar, Gas, Energy Transition, and Energy Marketing segments. The Hydro segment holds interest of approximately 922 megawatts (MW) of owned hydroelectric generating capacity located in Alberta, British Columbia, and Ontario. The Wind and Solar segment has a net ownership interest of approximately 2,057 MW of owned wind and solar electrical-generating capacity, as well as battery storage facilities located in Alberta, Ontario, New Brunswick, and Québec in Canada; the states of Massachusetts, Minnesota, New Hampshire, North Carolina, Pennsylvania, Washington, and Wyoming in the United States; and the state of Western Australia. The Gas segment has a net ownership interest of approximately 2,775 MW of owned gas electrical-generating capacity, and facilities located in Alberta, Ontario, Michigan, and the state of Western Australia. The Energy Transition segment has a net ownership interest of approximately 671 MW of owned coal electrical-generating capacity, as well as operates the Skookumchuck hydro facility in Centralia; and engages in the highvale mine and the mine reclamation activities. The Energy Marketing segment is involved in the trading of power, natural gas, and environmental products. It serves customers in various industry segments, including commercial real estate, municipal, manufacturing, industrial, hospitality, finance, and oil and gas. TransAlta Corporation was founded in 1909 and is headquartered in Calgary, Canada.