Permian Basin natural-gas boom leads to higher than expected methane emissions, analysis finds

Methane emissions from New Mexico's oil and gas industry are almost twice as much as previous estimates, according to an analysis of Environmental Protection Agency data by the Environmental Defense Fund, Mike Lee reports for Energy & Environment News. Methane is the main ingredient in natural gas and a powerful greenhouse gas that traps heat more efficiently than carbon dioxide.

New Mexico drillers and pipeline operators release about 1 million metric tons of methane into the atmosphere, almost three fourths of that from Permian Basin oil field, the analysis found. "EDF worked with researchers at the University of Wyoming to measure methane emissions at more than 90 well sites in the Permian Basin. After calculating an estimate for the basin from those figures, the group added estimates for other oil and gas sources to arrive at the 1 million-ton estimate," Lee reports. "Nationwide, the oil, gas and midstream pipeline industries emit about 13 million metric tons of methane annually, EDF has previously estimated."
The New Mexico Oil and Gas Association disputes the analysis, and the New Mexico Environment Department said the estimates could be inaccurate if the researchers did not account for the fact that emissions are intermittent, not constant, Lee reports. "An image taken of methane emissions from an oil and gas production facility is a snapshot in time, and may not be representative of the long term steady state methane emission rate coming from the facility," said Liz Bisbey-Kuehn, the state Environment Department's air quality bureau chief.

Permian Basin production "has roughly doubled in the past three years, and so much gas is produced alongside the region's oil that exploration companies can't get rid of it," Lee reports. "America's hottest oil patch is producing so much natural gas that by the end of last year producers were burning off more than enough of the fuel to meet residential demand across the whole of Texas. The phenomenon has likely only intensified since then," Kevin Crowley and Ryan Collins report for Bloomberg.

The methane emissions in New Mexico and Texas come from either accidental venting, such as when a seal is not tight enough, or deliberately releasing gas that can't be easily captured and stored in a controversial practice called "flaring."

"The amount of gas flared in the Permian rose about 85 percent last year, according to data from Oslo-based consultant Rystad Energy. Some 533 million cubic feet a day was burned in the fourth quarter alone," Crowley and Collins report.