Methane Leaks - Seeking Accurate Reports

Mar 26

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“Startlingly large amounts of methane are leaking from wells and pipelines in New Mexico, according to a new analysis of aerial data, suggesting that the oil and gas industry may be contributing more to climate change than was previously known. The study, by researchers at Stanford University, estimates that oil and gas operations in New Mexico’s Permian Basin are releasing 194 metric tons per hour of methane, a planet-warming gas many times more potent than carbon dioxide. That is more than six times as much as the latest estimate from the Environmental Protection Agency…”*

“The Permian Basin in Texas and New Mexico produces more oil than all but five countries in the world. …Over the past decade, Permian oil production has quadrupled and gas production has tripled….* *

“…Methane, the primary constituent of natural gas (NG), is a potent greenhouse gas (GHG) with a global warming potential 28–36 times larger than carbon dioxide over a 100-year time horizon and 84–87 times larger over 20 years. …Despite the accelerating transition to renewable energy, NG continues to account for 34% of U.S. primary energy consumption as of 2020. ..Therefore, reducing the GHG intensity of oil and gas (O&G) through preventing methane emissions is an important mitigation opportunity. A number of studies have found abnormally high methane emissions from O&G operations in the Permian Basin. ..Because of the different methods and coverage areas of these studies, direct comparison of their results is challenging and uncertainty remains about the emission rates in the Permian Basin. However, these studies consistently find emissions significantly in excess of government estimates. The U.S. Environmental Protection Agency (EPA) Greenhouse Gas Inventory (GHGI) estimates a national NG production loss rate of 1.5%, …but the GHGI has been identified as a conservative estimate of methane emissions… We bridge this gap using a novel approach: A basin-wide aerial survey capable of measuring emissions from nearly every asset in an O&G producing region with an instrument capable of quantifying and attributing medium-to-large point-source emissions. This work allows us to identify emissions larger than any documented in ground-based surveys, and to obtain sample sizes orders of magnitude larger than prior approaches….”** “We estimate total O&G methane emissions in this area at 194 (+72/–68, 95% CI) metric tonnes per hour (t/h), or 9.4% (+3.5%/–3.3%) of gross gas production.** REPORT, Abstract

“…Ramón Alvarez, an atmospheric chemist at the Environmental Defense Fund, estimated about a decade ago that the break-even point — the point above which natural gas would actually hurt the climate more than coal — was a 3.1 percent methane leakage rate. Based on more recent data from the Intergovernmental Panel on Climate Change, Dr. Howarth estimates that the threshold is closer to 2.8 or 2.9 percent.

That makes the 9.4 percent leakage rate in the new study highly alarming, experts said, though they emphasized that the rate in the Permian Basin might not be comparable to rates elsewhere….

If there was good news in the study, it was that a small number of oil and gas sites contributed disproportionately to emissions — suggesting that, if the worst offenders change their practices, it is possible for the industry to operate more cleanly.”*

“The net climate impact of gas and coal life-cycle emissions are highly dependent on methane leakage. Every molecule of methane leaked alters the climate advantage because methane warms the planet significantly more than CO2 over its decade-long lifetime. We find that global gas systems that leak over 4.7% of their methane (when considering a 20-year timeframe) or 7.6% (when considering a 100-year timeframe) are on par with life-cycle coal emissions from methane leaking coal mines. The net climate impact from coal is also influenced by SO2 emissions, which react to form sulfate aerosols that mask warming. We run scenarios that combine varying methane leakage rates from coal and gas with low to high SO2 emissions based on coal sulfur content, flue gas scrubber efficiency, and sulfate aerosol global warming potentials. The methane and SO2 co-emitted with CO2 alter the emissions parity between gas and coal. We estimate that a gas system leakage rate as low as 0.2% is on par with coal, assuming 1.5% sulfur coal that is scrubbed at a 90% efficiency with no coal mine methane when considering climate effects over a 20-year timeframe. Recent aerial measurement surveys of US oil and gas production basins find wide-ranging natural gas leak rates 0.65% to 66.2%, with similar leakage rates detected worldwide. These numerous super-emitting gas systems being detected globally underscore the need to accelerate methane emissions detection, accounting, and management practices to certify that gas assets are less emissions intensive than coal.”

Evaluating net life-cycle greenhouse gas emissions intensities from gas and coal at varying methane leakage rates

Deborah Gordon1, Frances Reuland2, Daniel J Jacob3, John R Worden4, Drew T Shindell5 and Mark Dyson6

DOI 10.1088/1748-9326/ace3db

* Methane Leaks in New Mexico Far Exceed Current Estimates, Study Suggests, New York Times, By Maggie Astor, March 24, 2022

** Quantifying Regional Methane Emissions in the New Mexico Permian Basin with a Comprehensive Aerial Survey, Environ. Sci. Technol. 2022, Publication Date: March 23, 2022, https://doi.org.10.1021/acs.est.1c06458, copyright 2022 The Authors. Published by American Chemical Society. Figure 4.

**Art is derived from graph (a) on left.