Vectren Corporation is an energy holding company headquartered in Evansville, Ind. Vectren's wholly owned subsidiary, Vectren Utility Holdings, Inc., serves as the intermediate holding company for three operating utilities.

Nicor Gas serves more than 2.1 million customers in northern Illinois, excluding the city of Chicago.

Peoples Gas, a subsidiary of WEC Energy Group (NYSE: WEC), is a regulated natural gas delivery company that serves approximately 830,000 residential, commercial, and industrial customers in the city of Chicago.

The Detroit-based DTE Energy develops and manages energy-related businesses and services nationwide. Its operating units include an electric utility serving 2.2 million customers and a natural gas utility serving 1.3 million customers.

Helps energize the lives of its nearly 4 million natural gas & electric customers across seven states. Our local utilities - Columbia Gas & NIPSCO - ensure that customers receive safe, reliable & affordable natural gas & electric service.

We're a company with more than 5 million metered customers & a long history of service.

In addition to providing natural gas to homes and businesses of all sizes, Piedmont Natural Gas also sells, installs and repairs natural gas appliances and equipment for homes and businesses offers repair plans.

ComEd provides electric service to approximately 3.8 million customers across northern Illinois, or 70 percent of the state's population. ComEd is a subsidiary of Exelon Corporation, the nation's leading competitive energy supplier.