According to the latest EIA estimates, US energy-related CO2 emissions declined by 3.8% in 2012. Energy-related carbon dioxide emissions have declined in 5 out of the last 7 years. The 2012 downturn means that emissions are at their lowest level since 1994 and over 12% below the recent 2007 peak. After 1990, only the recession year of 2009 saw a larger percentage emissions decrease than 2012. A large drop in energy intensity (energy consumption per unit of GDP, -5.1% in 2012 as GDP increased by 2.8% and energy consumption fell by 2.4%) assisted the 2012 decline in energy-related carbon dioxide emissions despite economic growth. The combined reduction in energy use per dollar of GDP and the carbon intensity of the energy supply meant that the overall carbon intensity of the economy (CO2 per GDP) declined by 6.5% in 2012.
Half of the overall energy decline was from the residential sector (-5.7%), where a very warm first quarter of the year lowered energy demand and emissions. After the residential sector, the next biggest decline in energy consumption was in the transportation sector (22%) of the total energy decline. The substitution of gas for coal in power generation also contributed to cut CO2 emissions in 2012.