Carbon dioxide emissions decreased in all 50 states between 2005 and 2023, according to recently released data from the U.S. Energy Information Administration (EIA).
Total energy-related CO2 emissions in the United States fell 20% over that time, and the population grew by 14%, leading to a 30% decrease in per capita CO2 emissions. New Jersey realized even better results than that 30% national average with CO2 reductions of 36%.
CO2 emissions primarily declined nationwide because less coal was burned in the electric power sector, EIA said. Increased electricity generation from natural gas, which releases about half as many CO2 emissions per unit of energy when combusted as coal, and non-CO2-emitting wind and solar generation have offset the decrease in coal generation.
Maryland led all states with a 49% reduction in per capita CO2 emissions from energy consumption between 2005 and 2023, followed by Washington, D.C. (-48%), Georgia (-45%), Delaware (-43%) and North Carolina (-42%). The state with the least change was Mississippi where CO2 emissions declined by only -1%, followed by Idaho (-3%), and South Dakota (-4%).
In 2023, the transportation sector had the most CO2 emissions in almost all states along the east and west coasts of the contiguous United States in 2023. These states are generally more densely populated and have more road and air travel. Many of these coastal states also do not consume coal for electricity generation anymore, meaning electric power sector CO2 emissions have declined since 2005.
The industrial sector, which includes manufacturing and agriculture, accounted for the largest share of CO2 emissions in four states. Large oil, natural gas, and refining industries in Texas, Louisiana, and Alaska, and large agriculture and biofuels production industries in Iowa contribute to higher industrial emissions in these states.
Looking ahead, EIA’s Short-Term Energy Outlook forecasts a slight 1% increase in U.S. total CO2 emissions in 2025, in part because of more recent increased fossil fuel consumption for crude oil production and electricity generation growth.
