Tankers Shipping U.S. LNG Emit More Greenhouse Gases Than Electric Cars Can Offset
A single year of emissions from U.S. liquefied natural gas (LNG) exports by ship outweighs the climate benefits of every electric vehicle on American roads, according to a new analysis reported by Phil McKenna and Peter Aldhous for Inside Climate News.
Between 2017 and 2024, annual emissions from LNG tankers surged from 4.1 million to 18.4 million metric tons of CO₂ equivalent, driven by a fivefold increase in voyages. Most emissions stem from methane leaks during shipping, especially from poorly loaded auxiliary engines, making the process more polluting than widely assumed.
The Trump administration has greenlit several new LNG projects, even as global shipping regulations tighten and concerns grow about the full lifecycle emissions of exported gas. “Shipping emissions are not really taken into account by either the exporting country or the importing country,” said Alison Kirsch, senior energy analyst at the Sierra Club.
Methane, the core component of natural gas, is a potent greenhouse gas, packing 80 times more warming power than carbon dioxide over a 20-year span. While it dissipates faster, its short-term punch makes it a prime target in the fight to slow global warming. The growing trade in liquefied natural gas has long been sold as a cleaner alternative to coal, but shipping it across oceans reveals an underappreciated climate toll. From fracking fields to foreign ports, every step leaks gas, with tankers releasing methane through a phenomenon known as “methane slip.” These emissions often go unmeasured, thanks to a regulatory blind spot over international waters and the technical challenges of satellite monitoring at sea.
The industry’s unchecked growth raises questions about whether gas can truly serve as a “bridge fuel” in the transition to clean energy, or if it simply paves a longer road of fossil fuel dependence.
