U.S. energy-related carbon emissions dropped to an 18-year low in 2012.
A U.S. Energy Information Administration (EIA) report released Oct. 21 showed that they dropped 12 percent below the 2007 peak, to 5,290 million metric tons. The numbers have declined in 5 of the last 7 years.
The decline is being credited to electric power stations using natural gas rather than burning carbon-intensive coal. The cheaper natural gas burns with about half the carbon emissions.
The general public also played a role, reducing residential energy usage across the country by 2.4 percent. A warmer winter helped lower the demand for home heating.
The study meets the goals of an earlier legislative effort to lower energy-related carbon emissions, even though the, which would have forced the issue, was killed in 2010.
The Waxman-Markey bill aimed to cut emissions to 3 percent below the 2005 levels. The Oct. 21 report shows that the levels are now 11.8 percent below those 2005 figures.
U.S. emissions dropped 3.8 percent in 2012. The only year to see a larger drop was in the depths of the recession, in 2009, when emissions declined 7.1 percent. 2012 saw the largest drop in a year with positive GDP, as the economy grew 2.8 percent. It is the only time carbon emissions have declined when GDP growth was more than 2 percent.
The report notes an increased use of wind turbines to generate energy, but at the same time, hydropower generation dropped by an even greater amount. Overall, reliance on renewable energy declined.
The EIA cautioned against drawing substantial conclusions from this report because it only covers one year of data.
But the report offered a look ahead at ways to continue on this path, writing, "Other factors, such as improvements in vehicle fuel efficiency and increased use of renewable generation, however, could play a continuing role in subsequent years."