EIA's Annual Energy Outlook 2015 (AEO2015) Reference case projects that electricity consumption will increase at an average annual rate of 0.8% from 2013 to 2040, nearly in line with expected population growth. Continuing a recent trend toward lower levels of carbon-intensive generation, natural gas and renewable generation meet almost all of the increase.Electricity generation from renewable sources provided 13% of U.S. electricity in 2013. In the AEO2015 Reference case, which reflects current laws and regulations—but not pending rules, such as the Environmental Protection Agency's Clean Power Plan—this percentage is projected to increase to 18% by 2040.
Geothermal generation grows at an average annual rate of about 5.5% over the projection period, but because geothermal resources are concentrated geographically, the growth is limited to the western United States. The report estimates that geothermal electricity generation will increase from 16.88 billion kilowatthours in 2015 to 69.56 billion kilowatthours in 2040.
