FIVE FACTS ON RMI’S FLAWED NATURAL GAS LEAKAGE RATE STUDY
JULY 20, 2023 | NICOLE JACOBS
FIVE FACTS ON RMI’S FLAWED NATURAL GAS LEAKAGE RATE STUDY
JULY 20, 2023 | NICOLE JACOBS
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Claims that the leakage rate of natural gas wells and infrastructure make the resource worse for the environment than coal are once again circulating – and using the same debunked methodology as previous research by Food and Water Watch board member and Cornell professor Robert Howarth.
In the latest study, RMI is moving the needle on the threshold for natural gas to maintain climate benefits and using cherry-picked studies and uncorroborated aerial methane readings to allege that leakages in the natural gas system make natural gas as bad or worse than coal.
The study is part of RMI’s long-standing attempt to move investment away from the natural gas system and into its preferred energy pathways, even if it results in growing emission rates from an under-resourced system.
Here’s a few important facts to keep in mind when reading this study:
Fact #1: Methane leakage rate thresholds are far higher than RMI describes.
RMI uses the following graphic on its Natural Gas vs. Coal website that seems to imply that any leakage rate over 2 percent negates the climate benefits of natural gas. And not just by a small amount. At a potential 3.3 percent leakage rate – which is lower than most 20-year threshold estimates – the organization says natural gas is 19 percent worse than coal.
Oddly given this, in the study’s abstract, RMI says the climate benefits of natural gas are negated at 4.7 percent over a 20-year timeframe and 7.6 percent for a 100-year timeframe, which is roughly the same as what the International Energy Agency has said.
Source: International Energy Agency
RMI acknowledges that the threshold is subject to variation across studies, with one study they cite (Tanaka 2019) finding the upper leakage bound to be as high as 9 percent, and a selection of other studies suggesting the same:
What is the methane leakage rate threshold for natural gas to maintain its climate benefits?StudyLower End EstimateHigher End EstimateModelTanaka et al., 20193%9%GWP and GTPRoman-White et al., 20193.1%9.1%GWPAbrahams et al., 20156%9%GWPHausfather, 20155.2%9.9%GWPEnvironmental Defense Fund, 2012N/A3.2%TWP
Fact #2: RMI is using cherry-picked studies to bolster its claims.
The studies used to create RMI’s dataset isn’t explained by study authors, providing no rhyme or reason as to the selection criteria or how they balanced the choices.
At a cursory glance, the studies used aren’t an easy translation into the American context either and can’t be applied to the domestic industry. One in particular, Tanaka 2019, is cited four times, providing global emission rates for American, Indian, Chinese, and German sources. This one study comprised four data points of an 18-point dataset, and clearly showed that the United States has the lowest natural gas emission intensity of the entire dataset.
When duplicate studies are counted only once, there are less than ten studies selected, and not all of them are focused on U.S. emission rates.
Fact #3: RMI creates its own calculation for methane’s CO2 equivalent that far exceeds the scientific consensus.
The study does not disclose it is using a different calculation of natural gas (methane)’s CO2 equivalent than the EPA which measures methane’s global warming potential (GWP) as 25 times more potent than carbon dioxide over a 100 timeframe and having a significantly shorter duration in the atmosphere than CO2.
RMI’s study ignores the official metric in favor of its own, estimating methane’s GWP20 at 82.5 times more potent and a GWP100 of 30.
Fact #4: RMI uses uncorroborated aerial data for its emissions calculations.
RMI’s study uses a meta-analysis of data collected from other studies that rely on aerial surveys to estimate methane leakage. Not only are there limitations for these types of assessments and a lack of bottom-up measurements to validate sources of methane and duration of emissions, it is counterintuitive to what RMI’s website confirms is necessary to accurately measure emission rates. According to the website’s FAQ:
“Monitoring of methane emissions in the natural gas production process is performed through a combination of direct measurement and estimation techniques…Both direct measurement and estimation techniques are important for developing an accurate understanding of methane emissions from the natural gas industry.” (emphasis added)
The National Academy of Science is acutely aware of the limitation of pure top-down measurements and recommends improving national methane emissions inventories through a combination of top-down and bottom-up observations, and collaboration with industry and academia. A NAS report details:
“Coordinated, contemporaneous top-down and bottom-up measurement campaigns, conducted in a variety of source regions for anthropogenic methane emissions, are crucial for identifying knowledge gaps and prioritizing emission inventory improvements. Careful evaluation of such data for use in national methane inventories is necessary to ensure representativeness of annual average assessments.”
The flaw in aerial or satellite data comes from the monitoring of specific regions at specific moments in time and using these measurements for 24/7/365 calculations despite a snapshot potentially not being reflective of continuous emissions. Top-down monitoring provides snapshots, but cannot provide the entire picture.
Fact #5: The climate benefits of natural gas have been proven.
The new study from RMI distracts from the reality that natural gas operators are working to reduce leakage along the supply chain and natural gas has contributed to reduced emissions across the United States economy.
In 2020, the oil and natural gas industry created the Environmental Partnership to provide members with the tools to improve leak prevention, detection, and repair in their operations. Since then the program has expanded to include 70 percent of the industry and found a .05% leak occurrence rate across 2,000 sites surveyed – a testament to the industry’s work to reduce leaks along the supply chain. Industry partners are also working with the EPA’s voluntary oil and gas methane program to implement technologies and best practices to cut emissions.
In the power sector, increased consumption of natural gas for firm power generation is supporting the growth of intermittent renewable capacity, while decreasing overall emissions of conventional generation.
But instead of working with the industry on solutions to reduce leaks along the system, RMI and other “Keep It In the Ground” organizations are protesting new infrastructure that can contribute to emissions reductions, including increased pipeline capacity and new compressor stations.
Bottom Line: RMI’s study cherry picks and moves goal posts to justify its claims that natural gas does not have climate benefits – and is in fact worse for the environment than coal – while ignoring the clear data demonstrating the opposite. The reality is that natural gas has demonstrated climate benefits and has already helped the United States reduce emissions while providing reliable energy domestically and across the globe.