Last week saw the publication of an important scientific study on methane emissions at natural gas well sites – a study that should help inform our public policy debates about hydraulic fracturing. It provides additional evidence that, when undertaken using industry best practices, hydraulic fracturing can produce shale energy safely and responsibly.
The peer-reviewed study was conducted by a team of researchers at the University of Texas engineering school. Their efforts were supported by industry, including ExxonMobil, and the Environmental Defense Fund. The study is the first in a series through 2014 that seeks hard data on methane emissions across the entire natural gas system.
The UT researchers took measurements at 190 natural gas production sites – and nearly 500 wells – in every region of the United States where hydraulic fracturing is occurring. Nine leading energy companies allowed access to their operations but importantly it was the researchers themselves who chose at random all wells to be examined – without company input.
The study’s findings give plenty of reason to be encouraged about the future use of hydraulic fracturing for energy production.
UT’s sampling of well sites estimates the national leakage rate associated with the production phase of natural gas extraction to be equivalent to less than half of one percent of total natural gas produced.
It’s worth noting that this is much lower than early Environmental Protection Agency estimates of well-pad methane release, and is right in line with the most recently revised numbers issued by EPA.
This new research also seems to confirm the findings of a life-cycle analysis of natural gas production that ExxonMobil conducted in Pennsylvania’s Marcellus Shale. Those results were published this past spring in a peer-reviewed article in the journal Environmental Science and Technology.
Why are studies like these significant?
Because they come amid a national debate over the merits of hydraulic fracturing that has seen one charge in particular roil the discussion – namely, that methane seepage from natural gas production negates the benefits of reduced greenhouse-gas emissions our nation has experienced as electric utilities switch from coal to natural gas for power generation.
Of course, there is still more study required – particularly of midstream and downstream segments of the full natural gas supply chain. But thanks to the University of Texas, the Environmental Defense Fund, and others, we have taken a tremendous step forward in filling in our knowledge about the exact nature of fugitive methane emissions.