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.

Entergy Corporation, together with its subsidiaries, engages in the production and retail distribution of electricity in the United States. It generates, transmits, distributes, and sells electric power in portions of Arkansas, Louisiana, Mississippi, and Texas, including the City of New Orleans; and distributes natural gas. It also engages in the ownership of interests in non-nuclear power plants that sell electric power to wholesale customers, as well as provides decommissioning services to other nuclear power plant owners. It generates electricity through gas, nuclear, coal, hydro, and solar power sources. The company sells energy to retail power providers, utilities, electric power co-operatives, power trading organizations, and other power generation companies. The company's power plants have approximately 24,000 megawatts of electric generating capacity. It delivers electricity to 3 million utility customers in Arkansas, Louisiana, Mississippi, and Texas. Entergy Corporation was founded in 1913 and is headquartered in New Orleans, Louisiana.

FirstEnergy Corp., through its subsidiaries, generates, transmits, and distributes electricity in the United States. It operates through Regulated Distribution and Regulated Transmission segments. The company owns and operates coal-fired, nuclear, hydroelectric, wind, and solar power generating facilities. It operates 24,080 circuit miles of overhead and underground transmission lines; and electric distribution systems, including 274,518 miles of overhead pole line and underground conduit carrying primary, secondary, and street lighting circuits. The company serves approximately 6 million customers in Ohio, Pennsylvania, West Virginia, Maryland, New Jersey, and New York. FirstEnergy Corp. was incorporated in 1996 and is headquartered in Akron, Ohio.

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.

Portland General Electric Company, an integrated electric utility company, engages in the generation, wholesale purchase, transmission, distribution, and retail sale of electricity in the state of Oregon. It operates six thermal plants, three wind farms, and seven hydroelectric facilities. As of December 31, 2023, the company owned an electric transmission system consisting of 1,254 circuit miles, including 287 circuit miles of 500 kilovolt line, 413 circuit miles of 230 kilovolt line, and 554 miles of 115 kilovolt line; and served 934 thousand retail customers in 51 cities. It also has 28,868 circuit miles of distribution lines. Portland General Electric Company was founded in 1889 and is headquartered in Portland, Oregon.

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.

Avista Corporation, together with its subsidiaries, operates as an electric and natural gas utility company. It operates in two segments, Avista Utilities and AEL&P. The Avista Utilities segment provides electric distribution and transmission, and natural gas distribution services in parts of eastern Washington and northern Idaho; and natural gas distribution services in parts of northeastern and southwestern Oregon, as well as generates electricity in Washington, Idaho, Oregon, and Montana. This segment also engages in the supply of electricity to customers in Montana; and wholesale purchase and sale of electricity and natural gas. The AEL&P segment offers electric services in Juneau, Alaska. The company generates electricity through hydroelectric, thermal, wind, and solar generation facilities. As of December 31, 2023, it supplied retail electric services to approximately 416,000 customers; and retail natural gas services to approximately 381,000 customers. The company also operates five hydroelectric generation facilities with capacity of 102.7 MW; and four diesel generating facilities with a capacity of 107.5 MW. It also engages in venture fund investments, real estate investments, and other investments. Avista Corporation was incorporated in 1889 and is headquartered in Spokane, Washington.

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.