In the U.S. Energy Information Administration’s (EIA)
Annual Energy Outlook 2021 (AEO2021), EIA projects that U.S. energy-related carbon dioxide (CO2) emissions will decline for most years through the mid-2030s but then begin to rise slightly from the mid-2030s through 2050. In the AEO2021 Reference case, EIA projects that, by 2050, U.S. energy-related CO2 emissions will be 5% higher than 2020 levels.
EIA projects that decreases in CO2 emissions through the mid-2030s will largely be a result of changes in the carbon intensity (carbon dioxide per British thermal unit) of the fuel mix, especially in the electric power sector. EIA projects the mix of fuels used to generate electricity to continue to transition from relatively carbon-intensive coal to less carbon-intensive sources, such as natural gas, and carbon-free renewable energy.