Greenhouse gas emissions from the oil and gas sector are on the rise, but methane leakage continues to fall, according to new U.S. EPA data.
Petroleum and natural gas systems emitted 236 million metric tons of carbon dioxide equivalent into the atmosphere in 2014, up from 228 million metric tons CO2e in 2013, yesterday’s update to EPA’s Greenhouse Gas Reporting Program (GHGRP) shows. Methane emissions ticked down from 77 million metric tons CO2e in 2013 to 73 million metric tons CO2e last year, marking the third consecutive year that measurement has declined.
"The EPA expects that the GHGRP will be an important tool for the Agency and the public to analyze emissions and understand emissions trends," EPA wrote in its oil and gas emissions profile.
It could also serve as the basis for regulations like EPA’s proposed methane rule (Greenwire, Sept. 29). The agency’s latest numbers seem to undercut its own claims that emissions could rise more than 25 percent without new federal controls, said Steve Everley, spokesman for North Texans for Natural Gas.
"EPA has claimed that without new regulations, methane emissions will go up," he said. "What’s that based on?"
Reductions in methane emissions appear to be the result of existing regulation, and further cuts will be made possible only by additional rulemakings, said Matt Watson, associate vice president of the Environmental Defense Fund’s climate and energy program.
A table toward the bottom of EPA’s energy industry profile indicates that the bulk of emissions reductions between 2011 and 2014 came from gas well completions and workovers, a regulated source, he said.
"This data shows that regulations work, and promises of voluntary action don’t," Watson said in an emailed statement. "The largest methane reductions come from a practice that is subject to national standards, while the biggest increases come from sources that remain largely unregulated."
EPA cautioned that its data are limited. By the Environmental Defense Fund’s estimation, the data set covers about half of U.S. wells.