Posted on October 31, 2013 by LeAnne Burnett
Just like claims of fire from garden hoses and water contamination from hydraulic fracturing (“frack”) fluids, engineering estimates of the magnitude of methane emissions from natural gas production have varied widely, leading natural gas production opponents to face-off with energy companies. Fortunately concrete steps are now being taken to bring science to bear to help narrow the gap between the two sides. These steps come in the form of a joint project that actually measures methane emissions. Imagine! Cooperation, collaboration, and ditching polarizing polemics to find out what is really going on!
The first of 16 planned studies directly measured methane emissions at natural gas production sites in the United States. The Proceedings of the National Academy of Sciences has recently published the first results. These studies represent an organized effort among the Environmental Defense Fund, nine participating energy companies (Anadarko Petroleum Corporation; BG Group plc; Chevron; Encana Oil & Gas (USA) Inc.; Pioneer Natural Resources Company; SWEPI LP (Shell); Southwestern Energy; Talisman Energy USA; and XTO Energy, a subsidiary of ExxonMobil), an independent Scientific Advisory Panel and a study team from University of Texas, Cockrell School of Engineering. Dr. David Allen of the University of Texas at Austin led the study effort. Previous greenhouse gas emission analyses have been based on either engineering estimates or measurements made 100 meters to a kilometer downwind of the well site. The studied methane emissions are associated with 190 sites where unconventional natural gas production, specifically fracking, is used.
Uncommon features of this study are first and foremost the unique and perhaps anomalous partnership between the Environmental Defense Fund and energy companies, particularly given the adversarial relationship that has historically characterized the relationship between the environmental community and the energy industry. Second, the energy companies provided the study team direct access to 190 natural gas production sites so measurements could be taken directly at the source. Third, for several source categories, such as well completion operations, these data are the first reported direct, on-site methane emission measurements. The full data set, along with significant additional information, is now available online.
As an idea of one metric, the Environmental Protection Agency (“EPA”) current national inventory estimates well completion emission reductions at roughly one-half of potential emissions. This new study shows net or measured emissions for the total of 27 completions were 98% less than potential emissions. The large difference between the net emissions measured by the study and the net emissions estimated in the national inventory is due to several factors, including that emerging regulatory requirements and improved operating practices meant 67% of the wells sent methane to sales or control devices. For those wells with methane capture or control, 99% of the potential emissions were captured or controlled. And the wells with uncontrolled venting of methane had much lower than average potential to emit (0.55% of the average potential to emit in the national inventory).
Pragmatic environmentalists should welcome the studies as an aid to balanced decisions about energy choices facing the United States. Both gas boom critics and advocates now have rigorous scientific analysis to work with when considering regulation. Armed with knowledge rather than speculation, what a novel way to approach policy and regulation!