Ameren 

Operating across the United States, Ameren Corporation functions as a utility holding company. The enterprise organizes its operations into four primary divisions: Ameren Missouri, Ameren Illinois Electric Distribution, Ameren Illinois Natural Gas, and Ameren Transmission. Its fundamental business involves the rate-regulated production, transmission, and supply of electricity, in addition to the rate-regulated distribution and transmission of natural gas. Ameren generates power using a variety of sources, including coal, nuclear energy, and natural gas, supplemented by renewable alternatives such as hydroelectric, wind, methane gas, and solar. Its customer base encompasses residential homes, commercial businesses, and industrial operations. Established in 1881, Ameren Corporation is headquartered in St. Louis, Missouri.