Drawing on the latest data, an IEA report released today (June 20) provides a comprehensive new estimate of greenhouse gas emissions from across the global liquefied natural gas (LNG) supply chain and identifies key opportunities to bring them down.
Assessing Emissions from LNG Supply and Abatement Options examines upstream production, processing, pipeline transmission, liquefaction, shipping and regasification worldwide. The report estimates that greenhouse gas emissions associated with global LNG supply are roughly 350 million tonnes of carbon dioxide equivalent (Mt CO2-eq) annually. Around 70% of this is in the form of CO2 emissions that are either combusted or vented; the remaining 30% is methane that escapes unburnt into the atmosphere.
Globally, the average greenhouse gas emissions intensity of delivered LNG is just under 20 grammes of carbon dioxide equivalent per megajoule (g CO2-eq/MJ), compared with an average of 12 g CO2/MJ for natural gas supply overall. However, there are considerable variations across different geographies and supply routes.
According to the report, when all direct and indirect greenhouse gas emissions are factored in, more than 99% of the LNG consumed in 2024 had lower lifecycle emissions than coal. Globally, on average, LNG results in about 25% less emissions than coal. Nevertheless, the report emphasises that for those making an environmental case for LNG use, comparing it only to coal - the most carbon-intensive fuel - sets the bar too low, especially given the strong opportunities at hand for improving the emissions performance of LNG supply.
The report finds that emissions from LNG supply could be cut by more than 60% using today's technologies - and many measures could be implemented at low or moderate cost. Reducing methane leaks alone could cut annual emissions by close to 90 Mt CO2-eq, or 25% of total LNG emissions, and around half of that reduction could be realised at no net cost. Reducing flaring at the LNG facilities and fields providing feed gas could lower annual emissions by a further 5 Mt CO2-eq.
Other cost-effective strategies that could substantially reduce emissions include increasing process efficiency across the supply chain and implementing carbon capture, utilisation and storage (CCUS) at liquefaction facilities to capture the naturally occurring CO2 present in the feed gas. And while the upfront costs can be high, the electrification of upstream facilities and LNG terminals using electricity from low-emissions sources would further reduce the emissions by about 110 Mt CO2-eq.
The report forms part of the IEA's broader work on LNG markets, which play an important role in energy security. The report is being presented today by IEA Director of Energy Markets and Security Keisuke Sadamori at the 2025 LNG Producer-Consumer Conference in Japan, an annual event co-organised by Japan's Ministry of Economy, Trade and Industry and the IEA.
Assessing emissions from LNG supply and abatement options: Explore report
