Xcel Energy Inc. is a U.S. regulated electric utility and natural gas delivery company based in Minneapolis, Minnesota, serving more than 3.7 million electric customers and 2.1 million natural gas customers across parts of eight states (Colorado, Minnesota, Wisconsin, Michigan, North Dakota, South Dakota, Texas and New Mexico). It consists of four operating subsidiaries: Northern States Power-Minnesota, Northern States Power-Wisconsin, Public Service Company of Colorado, and Southwestern Public Service Co. In December 2018, Xcel Energy announced it would deliver 100 percent clean, carbon-free electricity by 2050, with an 80 percent carbon reduction by 2035 (from 2005 levels). This makes Xcel the first major US utility to set such a goal. History Xcel Energy was built on three companies: Minneapolis-based Northern States Power Company (NSP), Denver-based Public Service Company of Colorado (PSCo), and Amarillo-based Southwestern Public Service (SPS). Southwestern Public Service Co. (SPS) dates its origins to 1904 and the Pecos Valley in New Mexico when Maynard Gunsell received an electricity franchise for the city of Roswell, New Mexico and its 2,000 residents. The financial strain of creating this new enterprise soon overwhelmed him and he sold the franchise to W.H. Gillenwater, who named his utility the Roswell Electric Light Co. He later sold the company to an investment firm in Cleveland, Ohio, which already owned the Roswell Gas Co. Northern States Power Company's timeline begins with the organization of the Washington County Light & Power Co. in 1909. When H. M. Byllesby began building his utility holding company across the Northwestern region of the US, he renamed it the Consumers Power Co. in 1910 and which was renamed the Northern States Power Co. in 1916. While the bulk of NSP's territory grew across central and southern Minnesota (starting from the Twin Cities), it acquired territory in North Dakota (centering on Fargo, Grand Forks, and Minot) and extended southwest into South Dakota (centering on Sioux Falls). NSP's system also extended east into Wisconsin, but because of utility ownership laws in that state, it was operated as an entity separate from the rest of the company. Public Service Company of Colorado (PSCo) was formed in 1923 to provide an electric generating station for the Denver area. By 1924, it had acquired most of the electric companies in northern and central Colorado. Originally a subsidiary of Cities Service Company, it became an independent autonomous operation in November 1943. By this time, it served