How much US Emissions Improvements were from natural gas, nuclear, renewables and efficiency

US greenhouse gas emissions have gone down to below the level they were at in 1997 which met the Kyoto agreement. This happened even though the US did not sign the Kyoto agreement. Energy-related emissions of carbon dioxide, the greenhouse gas that is widely believed to contribute to global warming, have fallen 12% between 2005 and 2012 and are at their lowest level since 1994. Last year, 30% of power in the U.S. came from burning natural gas, up from 19% in 2005, driven by drilling technologies that have unlocked large and inexpensive new supplies of the fuel. While natural gas releases less CO2 than coal and oil, though, it’s still dogged by problems like methane emissions and water pollution, not to mention its volatility in pipelines. It’s often referred to as a “bridge fuel,” and as BNEF notes, the U.S. energy sector is starting to focus not just on the bridge itself, but also where it leads.

Natural gas wasn’t the only factor; improved efficiency for buildings and vehicles played a big role, too.

The US Energy Information administration provides data and analysis.

For energy source improvement – Natural gas helped more than renewables

The difference between the top two lines below is the efficiency gains and gains from weather factors and the second and third line gap shows the energy source improvement

Improvements from 1970 to 1988 were from increased use of nuclear power and higher mileage cars and improved buildings during that period

Leveraging Natural Gas to Reduce Greenhouse Gas Emissions by Center for Climate and Energy Solutions also has useful information.

The Washington Post describes that some of the Energy information administration information [carbon analysis] is only counting carbon-dioxide emissions from energy sources like coal, natural gas, and oil. This makes up about 84 percent of all of America’s greenhouse-gas emissions. But it leaves out other potent, heat-trapping gases like methane, which can leak out of natural gas operations, landfills, and farms. The EPA takes its own detailed inventory of those emissions, but a full assessment of last year won’t be out until 2015.

The White House has a proposed climate action plan out to 2020. President Obama has set a goal of 17 percent below 2005 levels by 2020.

SOURCES – EIA, Center for Climate and Energy Solutions, Watts up with that, Washington Post, White House, Wall Street Journal, EPA