According to the U.S. Energy Information Administration’s (EIA) State Energy Data System (SEDS), Illinois had the highest energy consumption in the Midwest and was the third-highest energy producer of any state in the region. In 2018, customers in Illinois consumed 4.0 quadrillion British thermal units (Btu) of energy, and 2.6 quadrillion Btu was produced in the state. Total energy production and consumption in Illinois each accounted for nearly 17% of the Midwest’s total.