A public utility company is an organization that maintains the infrastructure for a public service. Public utilities are subject to forms of public control and regulation ranging from local community-based groups to statewide government monopolies.
Southern Company is an American gas and electric utility holding company based in the southern United States. It is headquartered in Atlanta, Georgia, with executive offices also located in Birmingham, Alabama. The company is the second largest utility company in the U.S. in terms of customer base, as of 2021. Through its subsidiaries it serves 9 million gas and electric utility customers in 6 states. Southern Company's regulated regional electric utilities serve a 120,000-square-mile (310,000 km2) territory with 27,000 miles (43,000 km) of distribution lines.
GenOn Energy, Inc., based in Houston, Texas, United States, is an energy company that provided electricity to wholesale customers in the United States. The company is one of the largest independent power producers in the nation with more than 7,000 megawatts of power generation capacity across the United States using natural gas, fuel oil and coal. GenOn Energy is headquartered in the Reliant Energy Plaza in Downtown Houston. The company, formerly known as RRI Energy, acquired Mirant on December 3, 2010. The corporate names and logos of both RRI Energy and Mirant were retired.
ATCO Ltd., operating as the ATCO Group, is a publicly-traded Canadian engineering, logistics and energy holding company based in Calgary, Alberta. ATCO's subsidiaries include electric utilities, natural gas production and distribution companies, and construction companies.
Emera Incorporated is a publicly traded Canadian multinational energy holding company based in Halifax, Nova Scotia. Created in 1998 during the privatization of Nova Scotia Power, a provincial Crown corporation, Emera now invests in regulated electricity generation as well as transmission and distribution across North America and the Caribbean.
PPL Corporation is an energy company headquartered in Allentown, Pennsylvania in the Lehigh Valley region of eastern Pennsylvania. The company is publicly traded on the New York Stock Exchange.
Ferrellgas Partners, L.P. is an American supplier of propane founded 83–84 years ago in Atchison, Kansas by A.C. Ferrell. The nationwide company is headquartered in Liberty, Missouri.
Exelon Corporation is a public utility headquartered in Chicago, Illinois, and incorporated in Pennsylvania. Exelon is the largest electric parent company in the United States by revenue and is the largest regulated electric utility in the United States with approximately 10 million customers. The company is ranked 99th on the Fortune 500.
Constellation Energy Corporation is an American energy company headquartered in Baltimore, Maryland. The company provides electric power, natural gas, and energy management services. It has approximately two million customers across the continental United States.
Atmos Energy Corporation, headquartered in Dallas, Texas, is one of the United States' largest natural-gas-only distributors, serving about three million natural gas distribution customers in over 1,400 communities in nine states from the Blue Ridge Mountains in the East to the Rocky Mountains in the West.
NRG Energy, Inc. is an American energy company, headquartered in Houston, Texas. It was formerly the wholesale arm of Northern States Power Company (NSP), which became Xcel Energy, but became independent in 2000. NRG Energy is involved in energy generation and retail electricity. Their portfolio includes natural gas generation, coal generation, oil generation, nuclear generation, wind generation, utility-scale generation, and distributed solar generation. NRG serves over 7 million retail customers in 24 US states including Texas, Connecticut, Delaware, Illinois, Maryland, Massachusetts, New Jersey, New York, Pennsylvania, Ohio; the District of Columbia, and eight provinces in Canada.
NiSource Inc. is one of the largest fully regulated utility companies in the United States, serving approximately 3.5 million natural gas customers and 500,000 electric customers across six states through its local Columbia Gas and NIPSCO brands. The company, based in Merrillville, Indiana, has more than 8,000 employees. As of 2018, NiSource is the sole Indiana-based utility company.
Calpine Corporation is the largest generator of electricity from natural gas and geothermal resources in the United States, with operations in competitive power markets.
Integrys Energy Group, Inc. was an American energy company headquartered in Chicago, Illinois. It was formed by the merger of WPS Resources Corp. and Peoples Energy Corp. on February 21, 2007. The chairman, President, and chief executive officer was Charles A. Schrock. On June 23, 2014, Integrys announced that it was being acquired by Wisconsin Energy Corporation for $9.1 billion. Also in 2014, Integrys entered into an agreement to sell 100% of the Upper Peninsula Power Company (UPPCO) to Balfour Beatty Infrastructure Partners LP for $298.9 million.
WEC Energy Group is an American company based in Milwaukee, Wisconsin that provides electricity and natural gas to 4.4 million customers across four states.
Southern Company Gas, formerly AGL Resources, is an American Fortune 500 energy services holding company headquartered in Atlanta, Georgia. The company's operations consist of natural gas distribution, wholesale services, retail operations, and midstream operations. Southern Company Gas is one of the largest natural gas distribution companies in the United States. The company serves approximately 4.5 million utility customers through its regulated distribution subsidiaries across four states. Southern Company Gas made the Fortune 500 list in 2015, Forbes 2000 in 2006, and is a member of the S&P 500 Index. In 2016, Southern Company acquired AGL Resources and renamed it Southern Company Gas.
Intercontinental Exchange, Inc. (ICE) is an American company formed in 2000 that operates global financial exchanges and clearing houses and provides mortgage technology, data and listing services. Listed on the Fortune 500, S&P 500, and Russell 1000, the company owns exchanges for financial and commodity markets, and operates 12 regulated exchanges and marketplaces. This includes ICE futures exchanges in the United States, Canada and Europe, the Liffe futures exchanges in Europe, the New York Stock Exchange, equity options exchanges and OTC energy, credit and equity markets.
Spire Inc. is a regional public utility holding company based in St. Louis, Missouri, providing natural gas service through its regulated core utility operations while engaging in non-regulated activities that provide business opportunities. Its primary subsidiary Laclede Gas Company is the largest natural gas distribution utility in Missouri, serving approximately 631,000 residential, commercial and industrial customers in the City of St. Louis and ten counties in eastern Missouri. Its corporate headquarters is located in the 700 Market building in downtown St. Louis.
El Paso Electric is a Texas-based public utility company, engaging in the generation, transmission, and distribution of electricity in west Texas and southern New Mexico. Its energy sources consist of nuclear fuel, natural gas, purchased power, solar and wind turbines. The company owns six electrical generating facilities with a net dependable generating capability of approximately 2,010 megawatts. It serves approximately 437,000 residential, commercial, industrial, public authority, and wholesale customers.
UIL Holdings Corporation was a diversified energy delivery company serving a total of 690,000 electric and natural gas utility customers in 66 communities across two states, with combined total assets of over $4 billion. In 2015 it merged with Iberdrola USA to form Avangrid.
US$ 925.067 million (2010)