Exelon Corporation, a utility services holding company, engages in the energy distribution and transmission businesses in the United States and Canada. The company is involved in the purchase and regulated retail sale of electricity and natural gas, transmission and distribution of electricity, and distribution of natural gas to retail customers. It also offers support services, including legal, human resources, information technology, supply management, financial, engineering, customer operations, transmission and distribution planning, asset management, system operations, and power procurement services. It serves distribution utilities, municipalities, and financial institutions, as well as commercial, industrial, governmental, and residential customers. Exelon Corporation was incorporated in 1999 and is headquartered in Chicago, Illinois.

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.

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.

Evergy, Inc., together with its subsidiaries, engages in the generation, transmission, distribution, and sale of electricity in the United States. The company generates electricity through coal, landfill gas, uranium, and natural gas and oil sources, as well as solar, wind, other renewable sources. It serves residences, commercial firms, industrials, municipalities, and other electric utilities. The company was incorporated in 2017 and is headquartered in Kansas City, Missouri.

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.

Black Hills Corporation, through its subsidiaries, operates as an electric and natural gas utility company in the United States. The company operates in two segments: Electric Utilities and Gas Utilities. The Electric Utilities segment generates, transmits, and distributes electricity to approximately 222,000 electric utility customers in Colorado, Montana, South Dakota, and Wyoming; and owns and operates 1,394 megawatts of generation capacity and 9,106 miles of electric transmission and distribution lines. The Gas Utilities segment distributes natural gas to approximately 1,116,000 natural gas utility customers in Arkansas, Colorado, Iowa, Kansas, Nebraska, and Wyoming; owns and operates 4,663 miles of intrastate gas transmission pipelines; 42,514 miles of gas distribution mains and service lines; seven natural gas storage sites; and approximately 50,000 horsepower of compression and 516 miles of gathering lines. It also constructs and maintains customer owned gas infrastructure facilities for gas transportation customers; and provides appliance repair services to residential utility customers, as well as electrical system construction services to large industrial customers. In addition, the company produces electric power through wind, natural gas, and coal-fired generating plants; and coal at its coal mine located near Gillette, Wyoming. Black Hills Corporation was incorporated in 1941 and is headquartered in Rapid City, South Dakota.

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.