A new study led by the University measured the amount of methane emissions produced by 190 hydraulic fracturing well sites across the United States to fill gaps in current scientific literature. 

David Allen, a chemical engineering professor and the principal investigator and author for the study, said researchers sought to clarify gaps in the current scientific literature regarding what methane emissions are along the natural gas supply chain.

“The No. 1 finding is that for a category of emissions called completion flowback, the emissions that we found were much less than what are in the current national inventory,” Allen said. “The second major finding was for a different category of emissions — pneumatic controllers. We found much larger emissions than is in the current national estimates. Finally, if you combine all of our findings what we come up with is a total that is very similar to the current national inventory, but there is not as much from well completions and there is more from pneumatic controllers.” 

The study, which lasted nearly two years, was completed in partnership with the Environmental Defense Fund and nine natural gas production companies. 

Allen said the team was not surprised by the well completion information, seeing as in the fall of 2012, when the team was collecting data, regulations changed requiring reduced emissions completion equipment to be put in place at well completion sites.

“We want to go out and collect additional data to refine our understanding of what is causing [pneumatic controller] emissions to be higher than we expected,” Allen said. “That’s a natural part of doing research, to learn from what you’ve done and ask the next generation of questions.”

Drew Nelson, clean energy project manager at the Environmental Defense Fund, said Allen’s study is one of 16 studies the Environmental Defense Fund is helping to facilitate to learn what the leak rate of natural gas production is.

“Methane is a very potent greenhouse gas, and the more methane that is leaked into the atmosphere, the greater climate impact there is,” Nelson said. “We want to make sure that as folks switch from coal and gasoline and diesel to natural gas [so] that we’re not making things worse for the climate.” 

Mark Brownstein, the associate vice president and chief counsel of the U.S. Climate and Energy program at the Environmental Defense Fund, said he hopes to see improvements in the industry as a result of the study.

“There has been a raging debate about what are emissions associated with natural gas production,” Brownstein said. “Universally, people have been talking about the need to get actual data. This is actual data. It’s the first time that we’ve had the opportunity to get actual data from unconventional natural gas developers. There’s more work to be done, but this is a really important step.”

The last time UT released a study on fracking, a controversy emerged when it was revealed that Charles Groat, former UT geology professor and lead researcher for the 2012 study, was also a paid board member of Plains Exploration & Production Company, a company that performs hydraulic fracturing. The earlier study was not altered after this revelation, though Groat was removed from his position as head author.