New study suggests latest chapter in old tale: Methane leaks largely come from a few bad actors

Pipeline compressors can leak. (E&E)

The recent history of environmental regulation of energy producers in the United States is largely one of chasing a few bad actors who do most of the damage. That is reflected in the latest study of methane emissions by natural-gas companies, a problem that has reduced the appeal of natural gas as an alternative to coal for electricity generation.

"Published yesterday in Environmental Science & Technology, the paper is part of an ongoing effort by the Environmental Defense Fund to study how much methane is bleeding out of the U.S. gas supply system," Pamela King reports for Environment & Energy News. "The study suggests a small group of 'super-emitters' could be responsible for up to 40 percent" of the leaking gas, estimated to be worth $240 million a year.

The researchers, largely from Colorado State University, found that two of the 45 pipeline facilities they randomly sampled were emitting large amounts of gas. "Onsite observers indicated that venting was likely due to an anomalous condition, such as gas leaking through a faulty isolation valve," they reported. They estimated that "about 1 in 25 facilities is estimated to be a super-emitter at any one time." Methane is a much more potent greenhouse gas than carbon dioxide, though it beaks down sooner.

EDF Air Policy Director N. Jonathan Peress said companies that volunteered to participate in the study reported emissions 30 percent lower than non-participants, indicating that better regulatory standards are needed. "The trade group Interstate Natural Gas Association of America highlighted the CSU team's conclusion that average methane emissions from the gas-transmission and storage sector were 27 percent lower than EPA figures," King reports.