Aquila, Inc. was an electricity and natural gas distribution network headquartered in Kansas City, Missouri in the United States. The company also owned and operated power generation assets. It previously operated under the name UtiliCorp United, Inc. The company at one time ranked #33 on the Fortune 500 list. On February 6, 2007, the company announced plans for a merger valued at $1.7 billion to become a wholly owned subsidiary of Great Plains Energy. In conjunction with the merger Black Hills Corporation is to acquire its Colorado electric utility and the Colorado, Iowa, Kansas, and Nebraska gas utilities for $940 million. The merger closed on July 14, 2008, and Aquila now operates under the name Black Hills Energy. History Solomon Valley Milling Company Aquila has its roots in the Solomon Valley Milling Company founded in 1902 by Lemuel K. Green in Osborne, Kansas. The steam mill used to process flour and Green discovered he could sell electricity. In 1908 sold the mill and bought the H. M. Spalding Electric Light Plant in Concordia, Kansas. Prior to Green's purchase the plant generated power only dawn to midnight and was closed on Sundays. Green bought power from another flour mill and began selling power to neighboring towns. Green Power & Light Company In 1916 he sold the plant to the A.E. Fitkin & Company in New York City for $550,000. He then bought the Reeder Light, Ice & Fuel Company in Pleasant Hill, Missouri and renamed the company Green Power & Light Company. He then built Baldwin Lake which was used for hydroelectric power as well as provide water for the community. West Missouri Power Company In 1922 looking to expand with a generating plant at Clinton, Missouri he took the company public under the name West Missouri Power Company. Its chief rival in the Kansas City metropolitan area was Kansas City Power & Light. The company continued to expand through southwest Missouri. Missouri Public Service Company In 1926 he sold it to the Fitkin Group again which merged with the Missouri Public Service Company. Green retired to Escondido, California where bought a orange grove. He died in 1930. The Public Utilities Act of 1935 broke up utilities. Green's son Ralph Green bought controlling interest in Missouri Public Service. Green was to bring in Middle West Corporation, Missouri Gas & Electric Service Company and City Light and Traction Company of Sedalia, Missouri.