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.

WEC Energy Group, Inc., through its subsidiaries, provides regulated natural gas and electricity, and renewable and nonregulated renewable energy services in the United States. It operates through Wisconsin, Illinois, Other States, Electric Transmission, and Non-Utility Energy Infrastructure segments. The company generates and distributes electricity from coal, natural gas, oil, and nuclear, as well as renewable energy resources, including wind, solar, hydroelectric, and biomass; and distributes and transports natural gas. It also owns, maintains, monitors, and operates electric transmission systems; and generates, distributes, and sells steam. As of December 31, 2023, the company operated approximately 35,500 miles of overhead distribution lines and 36,500 miles of underground distribution cables, as well as 430 electric distribution substations and 523,700 line transformers; approximately 46,400 miles of natural gas distribution mains; 1,700 miles of natural gas transmission mains; 2.4 million natural gas lateral services; 490 natural gas distribution and transmission gate stations; and 69.3 billion cubic feet of working gas capacities in underground natural gas storage fields. The company was formerly known as Wisconsin Energy Corporation and changed its name to WEC Energy Group, Inc. in June 2015. WEC Energy Group, Inc. was founded in 1896 and is headquartered in Milwaukee, Wisconsin.

Ameren Corporation, together with its subsidiaries, operates as a public utility holding company in the United States. The company operates through four segments: Ameren Missouri, Ameren Illinois Electric Distribution, Ameren Illinois Natural Gas, and Ameren Transmission. It engages in the rate-regulated electric generation, transmission, and distribution activities; and rate-regulated natural gas distribution business. In addition, the company generates electricity through coal, nuclear, and natural gas, as well as renewable sources, such as hydroelectric, wind, methane gas, and solar. It serves residential, commercial, and industrial customers. The company was founded in 1881 and is headquartered in Saint Louis, Missouri.

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.

Avangrid, Inc., an energy services holding company, engages in the regulated energy transmission and distribution, and renewable energy generation businesses in the United States. The company operates through Networks and Renewables segments. It is involved in the generation, transmission, and distribution of electricity; and distribution, transportation, and sale of natural gas. In addition, the company operates renewable energy generation facilities primarily using onshore wind power, as well as solar, biomass, and thermal power. Further, it delivers natural gas and electricity to residential, commercial, and institutional customers through its regulated utilities in New York, Maine, Connecticut, and Massachusetts; and sells its output to investor-owned utilities, public utilities, and other credit-worthy entities, as well as generates and provides power and other services to federal and state agencies, institutional retail, and joint action agencies. Additionally, the company delivers thermal output to wholesale customers in the Western United States. It owns eight electric and natural gas utilities, serving 3.3 million customers in New York and New England, as well as owns and operates 9.3 gigawatts of electricity capacity primarily through wind power in 22 states. Avangrid, Inc. was incorporated in 1997 and is headquartered in Orange, Connecticut. The company operates as a subsidiary of Iberdrola, S.A.

Algonquin Power & Utilities Corp. operates in the power and utility industries in the United States, Canada, and other regions. The company operates in two segments, Regulated Services Group and Renewable Energy Group. The company primarily owns and operates a regulated electric, water distribution and wastewater collection, and natural gas utility systems and transmission operations. As of December 31, 2023, it provided distribution services to approximately 1,256,000 customer connections in the electric (approximately 309,000 customer connections), water and wastewater (approximately 572,000 customer connections), and natural gas sectors (approximately 375,000 customer connections). The company's electrical distribution utility systems and related transmission and generation assets are located in the states of Arkansas, California, Kansas, Missouri, Nevada, New Hampshire, and Oklahoma, and in Bermuda. Its regulated water distribution and wastewater collection utility systems are located in the states of Arizona, Arkansas, California, Illinois, Missouri, New York and Texas, and in Chile. The company's regulated natural gas distribution utility systems located in the province of New Brunswick and the states of Georgia, Illinois, Iowa, Massachusetts, Missouri, New Hampshire and New York. It also owns and operates generating assets with a gross capacity of approximately 2.0 gigawatt (GW) and has investments in generating assets with approximately 0.3 GW of net generation capacity. The company generates and sells electrical energy, capacity, ancillary products, and renewable attributes produced by its renewable and clean power generation facilities. It has economic interests in hydroelectric, wind, solar, renewable natural gas, and thermal facilities. As of December 31, 2023, it had a combined net generating capacity attributable to the Renewable Energy Group of approximately 2.7 GW. The company was incorporated in 1988 and is headquartered in Oakville, Canada.

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.

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.