Union Electric 

Operating as Ameren Missouri, the Union Electric Company functions as a regulated public utility. Its primary business involves generating, transmitting, and distributing electricity throughout Missouri. The company utilizes a diverse array of energy sources for power production, including coal, nuclear, natural gas, hydroelectric, methane gas, and solar. Complementing its electric services, it also manages a regulated natural gas distribution network. The utility delivers electricity to approximately 1.2 million customers and natural gas to 100,000 customers, covering a service territory of 24,000 square miles across central and eastern Missouri. Founded in 1881, Union Electric Company is headquartered in St. Louis, Missouri, and operates as a subsidiary of Ameren Corporation.