Ameren Corp

Ameren Corporation is the parent of AmerenCILCO, based in Peoria, IL; AmerenCIPS, based in Springfield, IL; Ameren IP, based in Decatur, IL; and AmerenUE, based in St. Louis, MO. Ameren was created by the 1997 merger of CIPSCO Incorporated and Union Electric Company, yet grew with two subsequent acquisitions, CILCORP Inc. and Illinois Power Company. Ameren employees, totaling approximately 9,400, provide energy services to approximately 2.3 million electric customers and more than 900,000 gas customers across nearly 64,000 square miles in Illinois and Missouri. Among the nation's top utility companies in size and sales, Ameren includes among its subsidiaries the following entities: AmerenEnergy, AmerenEnergy Resources, Ameren Services, CIPSCO Investment Company and CILCORP. Ameren affiliates own and operate nuclear, coal and natural gas fired generating plants in Illinois and Missouri.