Study: Methane emissions from oil and gas industry are higher than EPA estimates

Methane emissions from the oil and gas industry are actually higher than government estimates, says a study published in the Proceedings of the National Academy of Sciences, Gayathri Vaidyanathan reports for ClimateWire. "The study finds that daily leaks of the potent greenhouse gas from oil and gas wells in Texas' Barnett Shale matched the annual emissions of 8,000 cars."

"Methane is 86 times as warming as carbon dioxide on a 20-year time scale, according to the Intergovernmental Panel on Climate Change," Vaidyanathan writes. "The leak in the Barnett means that a Texan who uses natural gas would have a 50 percent greater climate impact over the next 20 years than a consumer elsewhere, said Steven Hamburg, chief scientist at the Environmental Defense Fund (EDF) and a co-author of the study." Hamburg said "the study justifies the need for regulations on existing sources. He told Vaidyanathan, "The data show that existing sources are a significant part of the problem."

The Environmental Protection Agency reported in October that oil and gas methane emissions were down, citing agency regulations as one of the causes in the reduction. The agency in August proposed regulations to further cut emissions, with final rules expected in June 2016. But the EDF study says "EPA is underestimating the industry's emissions by a factor of 2," Vaidyanathan writes.

"About 1.5 percent of the 103,312 metric tons of gas produced per day in 2013 leaked, the study finds," Vaidyanathan writes. "This equals a loss of $100 million per year in revenue. Accidents caused by human error—a person leaving a hatch open or a broken valve—at 10 percent of facilities were responsible for almost 90 percent of the emissions. And only 2 percent of facilities were responsible for almost half the emissions." (Read more)