NextEra Energy, Inc., through its subsidiaries, generates, transmits, distributes, and sells electric power to retail and wholesale customers in North America. The company generates electricity through wind, solar, nuclear,natural gas, and other clean energy. It also develops, constructs, and operates long-term contracted assets that consists of clean energy solutions, such as renewable generation facilities, battery storage projects, and electric transmission facilities; sells energy commodities; and owns, develops, constructs, manages and operates electric generation facilities in wholesale energy markets. The company had approximately 33,276 megawatts of net generating capacity; approximately 90,000 circuit miles of transmission and distribution lines; and 883 substations. It serves approximately 12 million people through approximately 5.9 million customer accounts in the east and lower west coasts of Florida. The company was formerly known as FPL Group, Inc. and changed its name to NextEra Energy, Inc. in 2010. NextEra Energy, Inc. was founded in 1925 and is headquartered in Juno Beach, Florida.

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.

NiSource Inc., an energy holding company, operates as a regulated natural gas and electric utility company in the United States. It operates in two segments, Gas Distribution Operations and Electric Operations. The company distributes natural gas to approximately 3.3 million customers through approximately 55,000 miles of distribution main pipeline and the associated individual customer service lines; and 1,000 miles of transmission main pipeline in northern Indiana, Ohio, Pennsylvania, Virginia, Kentucky, and Maryland. It also generates, transmits, and distributes electricity to approximately 0.5 million customers in various counties in the northern part of Indiana, as well as engages in wholesale electric and transmission transactions. It owns and operates coal-fired electric generating stations in Wheatfield and Michigan City; combined cycle gas turbine in West Terre Haute; natural gas generating units in Wheatfield; hydro generating plants in Carroll County and White County; wind generating units in White County, Indiana; and solar generating units in Jasper County and White County. The company was formerly known as NIPSCO Industries, Inc. and changed its name to NiSource Inc. in April 1999. NiSource Inc. was founded in 1847 and is headquartered in Merrillville, Indiana.

Alliant Energy Corporation operates as a utility holding company that provides regulated electricity and natural gas services in the United States. It operates in three segments: Utility Electric Operations, Utility Gas Operations, and Utility Other. The company, through its subsidiary, Interstate Power and Light Company (IPL), primarily generates and distributes electricity, and distributes and transports natural gas to retail customers in Iowa; sells electricity to wholesale customers in Minnesota, Illinois, and Iowa; and generates and distributes steam in Cedar Rapids, Iowa. Alliant Energy Corporation, through its other subsidiary, Wisconsin Power and Light Company (WPL), generates and distributes electricity, and distributes and transports natural gas to retail customers in Wisconsin; and sells electricity to wholesale customers in Wisconsin. It serves retail customers in the farming, agriculture, industrial manufacturing, chemical, packaging, and food industries, as well as wholesale customers comprising municipalities and rural electric cooperatives. In addition, the company owns and operates a short-line rail freight service in Iowa; a Mississippi River barge, rail, and truck freight terminal in Illinois; freight brokerage services; wind turbine blade recycling services; and a rail-served warehouse in Iowa. Further, it holds interests in a natural gas-fired electric generating unit near Sheboygan Falls, Wisconsin; and a wind farm located in Oklahoma. The company was formerly known as Interstate Energy Corp. and changed its name to Alliant Energy Corporation in May 1999. Alliant Energy Corporation was incorporated in 1981 and is headquartered in Madison, Wisconsin.

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.

NorthWestern Energy Group, Inc. provides electricity and natural gas to residential, commercial, and various industrial customers. It generates, purchases, transmits, and distributes electricity; and produces, purchases, stores, transmits, and distributes natural gas, as well as owns municipal franchises to provide natural gas service in the communities. The company operates 6,600 miles of electric transmission and 18,674 miles of electric distribution lines with approximately 395 transmission and distribution substations; and 2,235 miles of natural gas transmission and 5,155 miles of natural gas distribution lines with approximately 133 city gate stations in Montana. It also operates 1,310 miles of electric transmission and 2,365 miles of electric distribution lines in South Dakota with approximately 124 transmission and distribution substations; and 55 miles of natural gas transmission and 2,573 miles of natural gas distribution lines in South Dakota and Nebraska. The company provides electricity and/or natural gas to approximately 775,300 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. NorthWestern Energy Group, Inc. was founded in 1923 and is based in Sioux Falls, South Dakota.

MGE Energy, Inc., through its subsidiaries, operates as a public utility holding company primarily in the United States. It operates through Regulated Electric Utility Operations; Regulated Gas Utility Operations; Nonregulated Energy Operations; Transmission Investments; and All Other segments. The company generates, purchases, and distributes electricity and natural gas in Wisconsin and Iowa; owns and leases electric generating capacity; and plans, constructs, operates, maintains, and expands transmission facilities to provide transmission power services. It generates electricity from coal-fired, gas-fired, and renewable energy sources. As of December 31, 2023, the company owned and operated 835 miles of overhead electric distribution lines; 1,330 miles of underground electric distribution cables; 49 substations with an installed capacity of 1.2 million kVA; and gas facilities, including 3,066 miles of distribution mains, as well as supplied electric service to approximately 163,000 customers. MGE Energy, Inc. founded in 2001 and is headquartered in Madison, Wisconsin.