The U.S. oil and natural gas industry is releasing 60 percent more methane, a potent greenhouse gas, than the Environmental Protection Agency estimates, a report released Thursday says.
The study, published in the journal Science, found that crude oil and gas operations emit more than 28 billion pounds per year of methane, mostly from oil and gas wells, but also from other parts of the supply chain, such as storage and pipeline transport.
It estimates the leak rate from the U.S. oil and gas system to be 2.3 percent, compared to the EPA estimate of 1.4 percent. That might seem like a small amount, but it represents about 13 million metric tons each year, or enough natural gas to fuel 10 million homes.
“This is by far the most comprehensive body of research of its kind,” said Steven Hamburg, a scientist with the Environmental Defense Fund, which spearheaded the research with support from 19 co-authors from 15 other institutions. “Scientists have uncovered a huge problem, but also an enormous opportunity. Reducing methane emissions from the oil and gas sector is the fastest, most cost-effective way we have to slow the rate of warming today, even as the larger transition to lower-carbon energy continues.”
Methane, the main component in natural gas, is more potent than carbon dioxide because it traps more heat, although its greenhouse gas emissions are relatively short-lived in the atmosphere. Most climate scientists blame the greenhouse gases emitted from burning fossil fuels for driving man-made climate change.
Natural gas, a cheap, fast-rising energy source benefiting from the shale boom, is viewed as a cleaner fossil fuel than coal because it emits half as much carbon dioxide.
Energy companies have said they are committed to reduce methane emissions to combat climate change. Large energy companies including Shell, ExxonMobil, and BP signed a pledge last year to reduce emissions of methane from natural gas production.
The companies didn’t establish any specific emissions reductions targets, but they promised to “continually reduce methane emissions; advance strong performance across gas value chains; improve accuracy of methane emissions data; advocate sound policies and regulations on methane emissions; and increase transparency.”
The American Petroleum Institute, the main trade group representing the oil and gas industry, responded to the study by focusing on how companies have reduced methane emissions over time. The group says methane emissions have fallen 14 percent since 1990, as natural gas production has increased by more than half. API also challenged the methodology of the study, saying it may have overstated emissions by focusing only on airborne pollution.
“The industry has achieved continued emissions reductions thanks in large part to technology advancements and this innovation has been fundamentally important to our shared goal to reduce emissions,” said Erik Milito, director of API’s upstream group, representing exploration and production. “The natural gas and oil industry is committed to continuous improvement in operations, including safety, public health and reducing emissions from exploration and production sites.”
The Trump administration, meanwhile, has tried to repeal or delay Obama-era methane regulations, but has faced court setbacks.
Last year, a federal appeals court blocked the EPA from eliminating a regulation to limit methane emissions from new oil and natural gas wells.
A federal court ruled in February that the Interior Department’s Bureau of Land Management must enforce an Obama administration rule intended to cut methane emissions from natural gas drilling on public land. That court setback is likely temporary, however, since BLM is writing a new regulation that guts much of the Obama rule.
