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.
Constellation Energy Corporation is an energy company headquartered in Baltimore, Maryland, United States. The company provides electric power, natural gas, and energy management services. It has approximately two million customers across the continental United States.
Sonat, Inc., headquartered in Birmingham, Alabama, was a large Fortune 500 American energy holding company. The company was founded in 1928 and was listed on the New York Stock Exchange under the ticker symbol "SNT". Sonat was primarily involved in transmission and marketing natural gas and oil and gas exploration and production. The company was also involved in contract offshore drilling until 1995 when the offshore business became Transocean. In 1999 Sonat merged with El Paso Corporation. The company was headquartered in the AmSouth-Sonat Tower in downtown Birmingham.
Energen Corporation was a company engaged in hydrocarbon exploration. In 2018, the company was acquired by Diamondback Energy.
Oneok, Inc. is an American diversified corporation focused primarily on the natural gas industry, and headquartered in Tulsa, Oklahoma. The company is part of the Fortune 500 and S&P 500. Oneok was founded in 1906 as Oklahoma Natural Gas Company, but it changed its corporate name to Oneok in December 1980. It also owns major natural gas liquids (NGL) systems due to the 2005 acquisition of Koch Industries natural gas businesses.
UGI Corporation is a natural gas and electric power distribution company headquartered in King of Prussia, Pennsylvania, with extensive operations in the United States and Europe.
Avangrid, Inc., is an energy services and delivery company. AVANGRID serves about 3.1 million customers throughout New England, Pennsylvania and New York in the United States.
EQT Corporation is an American energy company engaged in hydrocarbon exploration and pipeline transport. It is headquartered in EQT Plaza in Pittsburgh, Pennsylvania.
Southern Natural Gas Company, headquartered in Birmingham, Alabama, is a natural gas pipeline company that was founded in 1928 and is currently a division of Kinder Morgan. The company was a division of Birmingham-based Sonat Inc. until 1999 when Sonat and El Paso Corporation merged. El Paso was acquired by Kinder Morgan in 2012.
Spectra Energy Corp, headquartered in Houston, Texas, operated in three key areas of the natural gas industry: transmission and storage, distribution, and gathering and processing. Spectra was formed in late 2006 from the spin-off from Duke Energy. Spectra owned the Texas Eastern Pipeline (TETCo), a major natural gas pipeline which brings gas from the Gulf of Mexico coast in Texas to the New York City area, which was one of the largest pipeline systems in the United States. Spectra also operated three oil pipelines. In February 2017, Spectra Energy merged into the Canadian company Enbridge.
Coastal Corporation was a diversified energy and petroleum products company headquartered at 9 Greenway Plaza in Greenway Plaza, Houston, Texas. The company was founded in 1955 by Oscar Wyatt and incorporated in 1955 as Coastal States Gas Producing Company. It merged with the El Paso Corporation in 2001. As of 1999, Coastal was a Fortune 500 company with 13,300 employees and annual revenues of $8.2 billion.
Capital Power is an independent power generation company based in Edmonton, Alberta, Canada. Capital Power develops, acquires, owns and operates power generation facilities using a variety of energy sources. Capital Power owns approximately 6,600 megawatts of power generation capacity at 27 facilities across North America.
Spire Inc. is a 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.
Walter Energy, Inc. was a publicly traded "pure play" metallurgical coal producer for the global steel industry. The company also produced natural gas, steam coal and industrial coal, anthracite, metallurgical coke, and coal bed methane gas. Corporate and U.S. headquarters were located in Birmingham, Alabama, and its Canadian & UK headquarters in Vancouver, British Columbia. Walter Energy filed for bankruptcy in 2015 and its assets were purchased by Warrior Met Coal.
Cenovus Energy Inc. is a Canadian integrated oil and natural gas company headquartered in Calgary, Alberta.
Missouri Gas Energy (MGE) was a natural gas distribution company headquartered in Kansas City, Missouri in the United States, with offices in St. Joseph, Lee's Summit, Warrensburg, Joplin, Republic, Neosho and Monett. MGE served over in 155 western Missouri communities and was a division of the Southern Union Company until it was ultimately sold to the Spire Inc. Its business is regulated by the Missouri Public Service Commission.
Mobile Gas, headquartered in Mobile, Alabama, was the largest natural gas utility in coastal Alabama that provided energy to 89,000 homes and businesses. Its operations dated back to 1836 when it began providing gas lighting for the city of Mobile. It had distribution territory in the cities of Mobile, Prichard, Saraland, Satsuma, Semmes, Bayou La Batre, Creola, Mt. Vernon, Spanish Fort, and Loxley. Within those cities, Mobile Gas operated 2,250 miles of pipeline and about 46 miles of transmission lines.
Diamondback Energy is a company engaged in hydrocarbon exploration headquartered in Midland, Texas.
