WASHINGTON Feb 5 Greenhouse gas emissions from
U.S. power plants fell 4.6 percent in 2011 as more generators
were switched to cleaner-burning natural gas and renewable
sources from coal, according to new data from the Environmental
The agency's second inventory of greenhouse gas emissions
reported by the country's largest industrial polluters showed
that power plants - which account for one-third of U.S.
emissions - released 2.22 billion metric tons of carbon dioxide
equivalent (CO2e) in 2011.
Despite the decline in power plant emissions, coal-fired
power plants continue to be the largest single source of carbon
emissions in the United States, the data showed.
The congressionally mandated EPA database covers 8,000
industrial sources that together emit more than 25,000 tonnes of
CO2e per year - large enough to be subject to some of the rules
being proposed by the EPA to curb greenhouse gas emissions.
This year, the database was expanded to include data on
methane emissions, which are generally produced by large
emitters in the oil and gas sector.
Oil and natural gas systems emitted 225 million tonnes of
CO2e in 2011, making them the second largest greenhouse gas
Environmental group The Environmental Defense Fund said in a
statement that the addition of methane to the EPA database will
be valuable as lawmakers and regulators consider how to regulate
emissions from the boom in U.S. natural gas production.
"Today's new data will provide insights into methane
emissions industrywide, which can help policymakers as well as
oil and gas operators identify cost-effective opportunities to
reduce pollution and prevent the waste of a valuable domestic
energy source," said Peter Zalal of EDF's Climate and Air legal
The EPA also showed that refineries increased their
greenhouse gas emissions by 0.5 percent in 2011 from 2010,
making them the third largest source of domestic greenhouse
(Reporting by Valerie Volcovici; editing by Jim Marshall)