U.S. natural gas production has boomed in the past decade, driving gas prices sharply downward. Natural gas has become a competitive choice for electricity generation, edging out coal. Because gas contains less carbon than coal, greenhouse gas emissions from power plants have dropped, and the U.S. grid has become cleaner, more efficient and more flexible. More natural gas is also entering the power sectors in Mexico and Canada.
But the low-carbon profile of natural gas doesn’t tell the whole story. Methane, its primary component, is a powerful greenhouse gas. It leaks to the atmosphere from wells and pipelines, contributing to climate change and reducing the climate benefit of using natural gas.
In 2016 U.S., Canadian and Mexican leaders pledged to reduce methane emissions from the oil and natural gas sector 40 to 45 percent below 2012 levels by 2025. Today, however, Canada is just beginning to contemplate more comprehensive regulatory limits on methane. Mexico has made only nonbinding pledges so far, and the Trump administration is rolling back federal methane regulation.
Scientists are still working to quantify methane emissions from oil and gas production, and to improve tools for detecting and reducing methane leaks. But even though much of the science is still uncertain, and the Trump administration is retreating from regulating methane leaks, we believe it is still possible and necessary to make progress on reducing methane emissions.
Many actors – including state and provincial governments, industry, and nongovernmental organizations – are working to advance methane measurement and mitigation efforts. To be effective, they need to work in concert. In a newly published synthesis article, we propose a North American Methane Reduction Framework to coordinate regulations, voluntary industry actions and scientific developments in methane estimation and mitigation. This approach can bridge the divide between science and policy, and drive new research that in turn can support better policies when governments are ready to act.
Measurement gaps and partial responses
Despite huge advances, large gaps in methane emissions inventories remain. The magnitude of leaks from oil and gas infrastructure remains disputed and insufficiently measured.
Regional studies have found that up to 90 percent of emissions come from a small number of sources that leak large amounts of methane into the atmosphere. Detecting and managing these “super-emitters” is an undeveloped area of research, but offers the potential for major reductions.
There also are many discrepancies in how methane emissions are measured from place to place. States and provinces have inconsistent reporting requirements, applying different thresholds over which facilities must report emissions. And there are unexplained differences between facility-level estimates of methane coming out of leaky valves and pipes on one hand, and measurements of methane in the atmosphere near oil and gas facilities.
Meanwhile, mitigation work is proceeding slowly. Companies have detected and limited some methane leaks, recapturing what represents lost product. However, earnings from recovering fugitive methane are not always sufficient to justify voluntary action.