Avista Utilities is a U.S. energy company. Avista generates and transmits electricity and distributes natural gas, while providing energy solutions for residential, commercial, and industrial customers. Approximately 1,550 employees provides 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. Avista Utilities is the regulated business unit of Avista Corp., an investor-owned corporation headquartered in Spokane, Washington. Avista Corp.s primary, non-utility subsidiary was Ecova, an energy and sustainability management company with over 700 expense management customers, representing more than 600,000 sites. In 2014 Ecova was sold to Cofely, a subsidiary of GDF Suez. The company was founded in 1889 as Washington Water Power Company, until the board of directors approved a name change to Avista Corporation, effective January 1, 1999.