Natural gas is often trumpeted as a clean fuel that can cut global emissions by exporting it and subsequently crowding out coal use in Asia and Europe. But a report from the Department of Energy finds that doing so may be just as, if not more, carbon intensive as if those countries used domestic coal.
According to Life Cycle Greenhouse Gas Perspective on Exporting Liquefied Natural Gas from the United States most carbon reductions garnered from natural gas use are largely offset by methane leakage from US production and the energy used in liquifying and transporting the fuel, reports the Washing Post Wonk Blog.
Compared to domestically produced and combusted gas, there is “a significant increase in the life cycle greenhouse emissions” that are attributed to the liquified natural gas supply chain, the report says. In some cases, transporting fuel this way to Shanghai would completely offset any greenhouse benefit when measured over a 20 year period. Climate benefits from exporting natural gas to other countries are also modest.
The increased use of natural gas will not drastically alter greenhouse gas emissions if targeted climate policy is not implemented, according to a report published in the journal Environmental Science & Technology in May.
According to models in Implications of Shale Gas Development for Climate Change, without any substantial policy changes, slightly increasing natural gas use increases overall energy use and “more substantially” encourages fuel switching. The combined effect will only slightly affect end-outcome greenhouse gas emissions, but whether that change will be a moderate increase or a moderate decrease depends on upstream methane emissions.