Widespread climate mitigation efforts have triggered energy transitions from coal to natural gas in many regions all over the world. Liquefied Natural Gas, or LNG, has been growing rapidly, and many nations view LNG as a significant source of energy they can use now and into the future. Though the use of natural gas, rather than coal, to generate electricity leads to significantly lower carbon dioxide emissions from the generating facility relative to the electricity generated, its full climate impact from the lifecycle of the fuel, which includes production, processing, and transportation isn’t quite as superior. The production and transportation of oil and gas releases a substantial amount of pollution, and although the momentum to mitigate methane emissions from the oil and gas supply chain is growing there are still gaps in emission estimates and regulations to address key sources of emissions in LNG production. To understand the full emission impact as well as opportunities for mitigation, we need to account for upstream emissions and the full lifecycle cost to the environment.
The LNG industry has grown at breakneck speed, but there is no corresponding effort to control methane or CO2 from LNG terminals and other sites that handle LNG, such as LNG storage facilities and transport operations. And while very few measurements have been made of LNG facility emissions, the sources are numerous. They include boil-off of methane from LNG in tanks and trucks, purging of transfer lines and vessels, and venting during the process of cooling down a warm truck or tank. LNG terminals also emit large amounts of CO2 from engines used to liquefy methane, which can instead be addressed via electrification or CO2 capture, utilization, or storage. It remains a challenge to get a full sense of the variability and range of lifecycle emissions associated with generating power from either coal or LNG at present or in the future scenarios.
Clean Air Task Force has developed the Life Cycle Assessment Tool (LCA) to begin to address this challenge. It is an interactive spreadsheet tool in which key parameters can be directly adjusted to specific local conditions, allowing the user to explore and compare different fuel options. This customizable model can be used to explore the range of lifecycle emissions associated with coal and natural gas power. With the addition of more detailed information, it can also calculate emissions associated with generating power in a specific country or at a specific facility.
This tool can help policy makers quickly compare the greenhouse gas impact of various coal and natural gas options. The LCA tool also highlights the need for and benefits of mitigation of LNG-related emissions. Reduction in methane emissions is clearest action we can take to substantially cut global warming in the next 20 years, helping us avoid critical tipping points. Addressing the life cycle emissions for LNG will be a critical component to staving off the worst impacts of climate change.
Check out our explainer video to learn more.