The Environmental Defense Fund (EDF) yesterday released the results of the first module of a multi-partner study on methane emissions in the natural gas fuel chain, published in the Proceedings of the National Academy of Sciences.
This study provides another important data source to assess fugitive methane emissions associated with natural gas production. According to the study results, the methane leakage rate is 2,300 gigagrams (Gg) or 0.42% of gross production, which aligns with the Environmental Protection Agency’s (EPA) latest estimates of 2,545 Gg (2011 national emissions inventory).
It’s also interesting to note that 99% of methane that could potentially be emitted is captured (or prevented from being emitted to the atmosphere), showing the progress already made by the industry. Pneumatic controllers and equipment leakage at the production site have been singled out as ongoing sources of methane emissions, giving the industry direction on where more reductions can be made.
This module is part of a series of studies that will assess the entire natural gas production, processing and supply chain. The “pump to wheels” module is expected to be released early/mid 2014. Westport is a partner in this effort and is supplying technical support to West Virginia University researchers who are field testing vehicles with Westport and Cummins Westport engines.
Westport is participating in the EDF study to improve understanding of the greenhouse gas (GHG) emission reduction benefits of commercial and heavy duty natural gas vehicles and fueling stations. Studies like this, with a range of industry partners like Shell, Volvo, Westport, Cummins Westport and fleet operators, offer the opportunity to collect data under real-world operating conditions. The study is being rigorously peer-reviewed, and will advance industry and academic knowledge about the GHG emissions reduction benefits of heavy-duty natural gas vehicles. Each of the modules will contribute to a more comprehensive understanding of the potential for methane leakage and opportunities for innovation and improvement.
The use of natural gas in transportation is a relatively new market; one that is evolving and improving and with the potential for deeper GHG emission reductions compared to diesel. These types of collaborations will help advance the industry, drive improvements across engines, vehicles and stations and uncover best practices to further safeguard the environmental advantages of natural gas.