NSTAR was a utility company that provided retail electricity and natural gas to 1.4 million customers in eastern and central Massachusetts, including the Boston urban area. NSTAR became a subsidiary of Northeast Utilities in April 2012. In February 2015, Northeast Utilities and all of its operating companies became one large company known as Eversource Energy.
Eversource Energy is a publicly traded, Fortune 500 energy company headquartered in Hartford, Connecticut, and Boston, Massachusetts, with several regulated subsidiaries offering retail electricity, natural gas service and water service to approximately 4 million customers in Connecticut, Massachusetts, and New Hampshire.
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.
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.
Duquesne Light Holdings, Inc. (“DLH”) is an energy services holding company formed in 1989 to serve as the holding company for Duquesne Light Company and to engage in certain unregulated energy and related businesses. After a 2007 acquisition, DLH is a wholly owned subsidiary of parent company DQE Holdings LLC, with principal executive offices located in Pittsburgh, Pennsylvania.
PNM Resources is an energy holding company based in New Mexico, in the United States. The acronym "PNM" by itself usually refers to the PNM Resources subsidiary Public Service Company of New Mexico.
Iberdrola is a Spanish multinational electric utility company based in Bilbao, Spain. Iberdrola has a workforce of around 34,000 employees serving around 31.67 million customers. Subsidiaries include Scottish Power and a significant part of Avangrid, amongst others. As of 2023, the largest shareholder of the company is the Qatar Investment Authority, with BlackRock and Norges Bank also holding significant interests.
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.
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.
Berkshire Hathaway Energy is a holding company that is 92% owned by Berkshire Hathaway. Berkshire has owned a controlling stake since 1999. The company also controls power distribution companies in the United Kingdom and Canada. The remaining 8% is owned by the family of Walter Scott Jr..
New York State Electric and Gas (NYSEG) is an electric and gas utility company owned by Avangrid that serves customers in New York. NYSEG was incorporated in 1852 as the Ithaca Gas Light Company. Throughout the end of the 19th century and the early part of the 20th century, the corporation went through mergers and acquisitions that combined about 200 utility companies under the name NYSEG. In 1975 the corporation became an 18% partner in the Niagara Mohawk Power Corporation’s Nine Mile Point nuclear plant, and in the 1980s NYSEG completed a series of hydroelectric power plants. In 2008 NYSEG became part of Iberdrola, when Iberdrola bought Energy East.
Avista Corporation is an American energy company which generates and transmits electricity and distributes natural gas to residential, commercial, and industrial customers. Approximately 1,550 employees provide electricity, natural gas, and other energy services to 359,000 electric and 320,000 natural gas customers in three western states. The service territory covers 30,000 square miles (78,000 km2) in eastern Washington, northern Idaho, and parts of southern and eastern Oregon, with a population of 1.5 million.
NextEra Energy, Inc. is an American energy company with about 58 GW of generating capacity, revenues of over $18 billion in 2020, and about 14,900 employees throughout the US and Canada. It is the largest electric utility holding company by market capitalization. Its subsidiaries include Florida Power & Light (FPL), NextEra Energy Resources (NEER), NextEra Energy Partners, Gulf Power Company, and NextEra Energy Services.
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.
The United Illuminating Company (UI) is a regional electric distribution company based in Orange, Connecticut. Established in 1899, UI is engaged in the purchase, transmission, distribution and sale of electricity and related services to 325,000 residential, commercial and industrial customers in 17 towns and cities in the greater New Haven and Bridgeport areas. It is a subsidiary of Avangrid.
Unitil Corporation is an interstate electricity and natural gas utility company that provides services for New Hampshire, Massachusetts and Maine. Its earliest predecessor company, the Portland Gas Light Company, was founded in Maine in 1849. The current company was set up in 1984 and is based in New Hampshire. With a market cap of 686.51M, it provides electric services to about 102,400 customers and natural gas to over 75,900 customers. The service territory of Unitil includes business districts and recreational centers as well as commercial and industrial business, such as electronic component manufacturers and education institutes. The company has an enterprise value of $766.54 million. The non-utility business is operated through the company's subsidiary, U-source, which is a national energy brokering and consulting company.
The Electric Bond and Share Company (Ebasco) was a United States electric utility holding company organized by General Electric. It was forced to divest its holding companies and reorganize due to the passage of the Public Utility Holding Company Act of 1935. Following the passage of the Act, the U.S. Securities and Exchange Commission (SEC) selected the largest of the U.S. holding companies, Ebasco to be the test case of the law before the U.S. Supreme Court. The court case known as Securities and Exchange Commission v. Electric Bond and Share company was settled in favor of the SEC on March 28, 1938. It took twenty-five years of legal action by the SEC to break up Ebasco and the other major U.S. electric holding companies until they conformed with the 1935 act. It was allowed to retain control of its foreign electric power holding company known as the American & Foreign Power Company (A&FP). After its reorganization, it became an investment company, but soon turned into a major designer and engineer of both fossil fuel and nuclear power electric generation facilities. Its involvement in the 1983 financial collapse of the Washington Public Power Supply System's five nuclear reactors led to Ebasco's demise because of the suspension of nuclear power orders and lawsuits that included numerous asbestos claims. The U.S. nuclear industry stopped all construction of new facilities following the 1979 nuclear meltdown at Three Mile Island, going into decline because of radiation safety concerns and major construction cost overruns.
