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.

Constellation Energy Corporation generates and sells electricity in the United States. It operates through five segments: Mid-Atlantic, Midwest, New York, ERCOT, and Other Power Regions. The company sells natural gas, energy-related products, and sustainable solutions. It has approximately 33,094 megawatts of generating capacity consisting of nuclear, wind, solar, natural gas, and hydroelectric assets. It serves distribution utilities; municipalities; cooperatives; and commercial, industrial, governmental, and residential customers. The company was incorporated in 2021 and is headquartered in Baltimore, Maryland.

PPL Corporation, an energy company, focuses on providing electricity and natural gas to approximately 3.6 million customers in the United States. It operates through three segments: Kentucky Regulated, Pennsylvania Regulated, and Rhode Island Regulated. The company delivers electricity to customers in Pennsylvania, Kentucky, Virginia, and Rhode Island; delivers natural gas to customers in Kentucky and Rhode Island; and generates electricity from power plants in Kentucky. PPL Corporation was founded in 1920 and is headquartered in Allentown, Pennsylvania.

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.

The AES Corporation, together with its subsidiaries, operates as a diversified power generation and utility company in the United States and internationally. The company owns and/or operates power plants to generate and sell power to customers, such as utilities, industrial users, and other intermediaries; owns and/or operates utilities to generate or purchase, distribute, transmit, and sell electricity to end-user customers in the residential, commercial, industrial, and governmental sectors; and generates and sells electricity on the wholesale market. It uses various fuels and technologies to generate electricity, such as coal, gas, hydro, wind, solar, and biomass, as well as renewables comprising energy storage and landfill gas. The company owns and/or operates a generation portfolio of approximately 34,596 megawatts and distributes power to 2.6 million customers. The company was formerly known as Applied Energy Services, Inc. and changed its name to The AES Corporation in April 2000. The AES Corporation was incorporated in 1981 and is headquartered in Arlington, Virginia.

Chesapeake Utilities Corporation operates as an energy delivery company. The company operates through two segments, Regulated Energy and Unregulated Energy. The Regulated Energy segment natural gas distribution operations in central and southern Delaware, Maryland's eastern shore, and Florida; regulated natural gas transmission in the Delmarva Peninsula, Ohio, and Florida; and regulated electric distribution in northeast and northwest Florida. The Unregulated Energy segment engages in the propane operations in the Mid-Atlantic region, North Carolina, South Carolina, and Florida; unregulated natural gas transmission/supply operation in central and eastern Ohio; generation of electricity and steam; provision of compressed natural gas, liquefied natural gas, and renewable natural gas transportation and pipeline solutions primarily to utilities and pipelines in the United States; and sustainable energy investments. This segment is also involved in the provision of other unregulated services, such as energy-related merchandise sale and heating, ventilation and air conditioning, and plumbing and electrical services. Chesapeake Utilities Corporation was founded in 1859 and is headquartered in Dover, Delaware.

RGC Resources, Inc., through its subsidiaries, operates as an energy services company. It sells and distributes natural gas to residential, commercial, and industrial customers in Roanoke, Virginia, and the surrounding localities. It operates approximately 1,180 miles of transmission and distribution pipeline; and a liquefied natural gas storage facility, as well as owns and operates eleven metering stations. The company also produces biogas. RGC Resources, Inc. was founded in 1883 and is based in Roanoke, Virginia.