Methane Emissions make Gas dirtier than Coal
How our energy system is based on a lie about gas
Switching from coal and oil to gas to supply heating and energy-intensive processes was seen as a great initiative to bring down carbon emissions. The assumption that gas is cleaner than other fossil fuels is based on the end use-combustion. When only that is considered “gas emits one-half as much CO2 than coal.” (Gordon et al 2023).
And that is nothing more than massaging the figures or lying about the real impact. Because the fact is that natural gas, methane, has big leaks. It leaks in production, it leaks in distribution and processing. And the leaking methane is 80 times worse than the carbon dioxide that goes into the atmosphere over a 20-year period, and almost 30 times worse over a 100-year period.
“We’re definitely under-accounting natural gas’s contribution to global warming relative to coal,” says Desirée Plata, the Associate Professor of Civil and Environmental Engineering and Director of the MIT Methane Network. According to her, leaks are not accounted properly, putting natural gas in a worse climate position than coal (MIT Climate)
Methane leaks when you bring it to the surface. In the fields, methane builds up pressure in pipes. Then it escapes through faulty valves and even faulty welds. And not just at the production site. It happens in pipelines, storage and distribution networks.
And these leaks, as studies in recent years have shown, are more dramatic than previously thought. For gas to be better than coal, studies found that methane leaks cannot be great. For coal mines, which have very low methane leaks themselves, it is only 1.8%.
How much methane does leak?
Methane leaks can be measured using satellites that monitor the wavelength of light. Methane is not visible, but it absorbs certain wavelengths of sunlight. Satellites can therefore detect larger leaks, especially in oil and gas fields. For smaller leaks, there are special cameras that use infrared technology. These include optical gas imaging cameras and hyperspectral cameras. While the latter are difficult to scale, the former provide a clear picture, especially when combined with satellites.
And here we look at the US, where there has been a huge increase in fossil fuel extraction. While the EPA does not publish the difference in the amount of methane emissions from leaks, researchers show that it increased massively between 2010 and 2019 (see Lu et al 2023).
The research group concludes: “We find significant underestimation in the national inventories of 2010 to 2019 oil/gas methane emissions across North America, prominently in the central-south and midwestern US, Alberta and Saskatchewan in Canada, and the Sureste onshore oil field in Mexico”. The US sites had emissions 70% higher than it was documented in their national report, Canada had 67% higher and Mexico 50% higher emissions than recorded in their respective national report
While the EPA estimates that between 1% and 1.4% of natural gas produced leaks, studies have found shocking figures. The Permian Basin in Texas and New Mexico leaks 3.7% (Zhang et al 2020). A study based on New Mexico in the US found leaks to be as high as 9% of production (Chen et al 2022), and in the UK, researcher Catherine Mitchell and her colleagues estimate that distribution pipe leaks were between 5.9% and 10.8% in 1990. Whether this has changed in the UK infrastructure is questionable.
A study has found that a 0.2% methane leakage from gas production can be equivalent to low-methane coal mines when sulphur (SO2) emissions are included. This is over the short warming potential of 20 years. This time frame is important to avoid tipping points in the climate system (see Gordon et al, 2023). With a leakage rate of 2%, natural gas could be on a par with coal and its methane emissions as determined by the IPCC, according to Gorden et al. As shown by Sherwin et al: US satellite data suggest a leakage rate of 2.95% for oil and gas fields (2024).
If this is the case in America, then production facilities in Russia, Turkmenistan or Iran, for example, where it is difficult to obtain data, will have comparable, if not worse, leaks.
The minimum leakage rate for this graph was one tonne per hour. This does not include, for example, leaks in distribution pipes, which occur everywhere, including in Europe.
Smaller leaks in distribution networks
In addition, smaller leaks in particular are difficult to detect and quantify. From pipes with leaky welds to compression plants and stations, leaks are everywhere. People like the methane trackers at the Clean Air Task Force, as well as individuals, have continued to highlight regional leaks. The CATF published a report showing 289 undocumented methane emissions - out of 430 sites visited across Europe. This means that two out of three oil and gas installations are leaking methane.
Leaks were particularly common in storage tanks, vents and unlit flares. In addition, pipelines at facilities such as wells, processing stations and pressure relief stations were identified as a major source of small leaks. As these small leaks are not very quantifiable, the problem of leakage and thus methane emissions might be even greater. With a realistic number of 2.8% of upstream emissions and additional proven downstream emissions, leaked methane is approximately on par with emissions from coal.
LNG – the dirtiest product
For LNG, there are not only leaks in production and distribution, but also major leaks and dirty energy use in processing, and inefficient fossil fuel transport. These additional sources of greenhouse gases, both CO2 and methane, are liquefaction, methane leakage during distribution to the tanker, combustion of the LNG or diesel in the tanker, and final transmission and distribution from port to end user. (cf. Howarth, 2024, p. 4852). This makes methane emissions from LNG production and distribution even more relevant, and lowers the threshold of potential leakage to lower emissions than coal. In the medium, not even in the upper case of possible methane leaks, LNG is very much dirtier than coal and diesel.
The complete life cycle assessment of Howarth shows in detail, how the methane emissions outweigh the carbon emissions of coal.
Conclusion
Methane emissions are a driver of climate change, and leaks have repeatedly been shown to be far higher than reported. Gas can easily be dirtier and more harmful than coal due to the large number of leaks in production, distribution and storage. If the leaks are on the proofed mean, LNG has more emissions than coal.
This means that measurements need to be taken. Monitoring and repairing leaks would be economically viable as it would increase volume. Consumers in Europe, however, have no influence over the repair of massive leaks from oil and gas wells. They need to take rapid action to stop leaks.
In addition, new gas stoves and heating systems in homes must be banned, reducing the need for LNG. Industry needs to electrify and new gas boilers should be avoided. Incentives for electrification are needed. Europe must become as gas independent as possible. Leaks in chemical industries using methane as a feedstock must be accounted for. There is also a need to reconsider direct reduction with gas in the steel industry and a life cycle analysis against coal.
This also puts serious question marks on the idea to have gas-fired power plants. The known potential to back up energy systems with long duration energy storage, from pumped hydro, mechanical energy storage and thermal energy storage with existing power plants, must be advanced and taken more into consideration as Europe cannot control the leaks and thus the emissions.
Sources
Deborah Gordon, Frances Reuland, Daniel J Jacob, John R Worden, Drew Shindell and Mark Dyson (2023): Evaluating net life-cycle greenhouse gas emissions intensities from gas and coal at varying methane leakage rates.
Environmental Research Letters, Volume 18, Number 8 DOI 10.1088/1748-9326/ace3db
Robert W. Howarth (2024): The greenhouse gas footprint of liquefied natural gas (LNG) exported from the United States. Energy Science & Engineering, Volume 12, Issue 11, Pages 4843-4859, https://doi.org/10.1002/ese3.1934.
Xiao Lu, Daniel J. Jacob , Yuzhong Zhang Lu Shen, Melissa P. Sulprizio, Joannes D. Maasakkers, Daniel J. Varon, Zhen Qu, Zichong Chen, Benjamin Hmiel, Robert J. Parker, Hartmut Boesch, Haolin Wang, Cheng He, and Shaojia Fan (2023): Observation-derived 2010-2019 trends in methane emissions and intensities from US oil and gas fields tied to activity metrics. Proceedings of the National Academy of Sciences (PNAS)120 (17). https://doi.org/10.1073/pnas.2217900120
Clean Air Task Force (2023): It Happens Here Too: Methane Pollution in Europe`s Oil and Gas Network. Online: https://www.catf.us/resource/it-happens-here-too-methane-pollution-europes-oil-gas-network/
Yuzhong Zhang, Ritesh Gautam, Sudhanshu Pandey, Mark Omara, Joannes D. Maasakkers, Pankaj Sadavarte, David Lyon, Hannah Nesser, Melissa P. Sulprizio, Daniel J. Varon, Ruixiong Zhang, Sander Houweling, Daniel ZavalaAraiza, Ramon A. Alvarez, Alba Lorente, Steven P. Hamburg, Ilse Aben, Daniel J. Jacob (2020) Quantifying methane emissions from the largest oil producing basin in the U.S. from space. Science Advances. https://legacy-assets.eenews.net/open_files/assets/2020/04/23/document_ew_03.pdf
Benjamin Storrow and E&E News (2020): Methane Leaks Erase Some of the Climate Benefits of Natural Gas. Scientific American (https://www.scientificamerican.com/article/methane-leaks-erase-some-of-the-climate-benefits-of-natural-gas/#:~:text=Scientists%20have%20long%20struggled%20to,by%20EPA%2C%20at%201.4%25.).
Yuanlei Chen*, Evan D. Sherwin, Elena S.F. Berman, Brian B. Jones, Matthew P. Gordon, Erin B. Wetherley, Eric A. Kort, Adam R. Brandt (2022): Quantifying Regional Methane Emissions in the New Mexico Permian Basin with a Comprehensive Aerial Survey. Energy and Climate, March. https://pubs.acs.org/doi/10.1021/acs.est.1c06458
Catherine Mitchell, Jim Sweet, Tim Jackson (1990): A study of leakage from the UK natural gas distribution system. Energy Policy Volume 18, Issue 9, Pages 809-818. https://doi.org/10.1016/0301-4215(90)90060-H
Andreas Forstmaier, Jia Chen, Florian Dietrich, Juan Bettinelli, Hossein Maazallahi, Carsten Schneider, Dominik Winkler, Xinxu Zhao, Taylor Jones, Carina van der Veen, Norman Wildmann, Moritz Makowski, Aydin Uzun, Friedrich Klappenbach, Hugo Denier van der Gon, Stefan Schwietzke, and Thomas Röckmann (2022): Quantification of methane emissions in Hamburg using a network of FTIR spectrometers and an inverse modeling approach. Atmospheric Chemistry and Physics, Volume 23, issue 12, https://doi.org/10.5194/acp-23-6897-2023.
Sherwin, E.D., Rutherford, J.S., Zhang, Z. et al. (2024): US oil and gas system emissions from nearly one million aerial site measurements. Nature 627, 328–334 (2024). https://doi.org/10.1038/s41586-024-07117-5