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Study Confirms Emissions Performance of CWI ISX12N Natural Gas Engine

Cummins Westport Inc. says an independent third-party study on the Cummins Westport ISX12N 400 hp natural gas engine has demonstrated that the engine meets and exceeds California Air Resources Board’s (CARB) optional Low NOx standard of 0.02 g/bhp-hr.

The study was carried out by The University of California, Riverside College of Engineering Center for Environmental Research and Technology, with funding provided by the South Coast Air Quality Management District, the California Energy Commission, and Southern California Gas Co. (SoCalGas). It confirms that natural gas engine technology provides one of the cleanest available options for on-highway transportation.

Engine testing was performed on a chassis dynamometer, with test cycles representative of operation in California’s South Coast Air Basin. Results showed that the ISX12N 400 hp engine met and exceeded the target NOx emissions throughout a range of duty cycles. When the engine operates on renewable natural gas, there are significant reductions in greenhouse gas emissions.  In addition to providing air quality and greenhouse gas benefits, the ISX12N can also take advantage of low natural gas prices and available incentive funds.

“Cummins Westport is proud to offer a viable, present-day solution to clearing the air, while giving customers the reliable performance they expect for their trucking applications,” said Bart van Aerle, President of Cummins Westport. “This study further confirms that the ISX12N, like the L9N natural gas engine, is one of the cleanest and economical options available for truck fleets today.”

The ISX12N, which has been in production since February 2018, was the first Class 8 truck engine for larger heavy-duty vehicles to certify to CARB’s optional Low NOx standard. It’s designed for regional haul, refuse, and vocational trucks, as well as motorcoach and commuter buses. Over 1,000 ISX12N engines have been produced for North American customers at the Cummins Jamestown, New York engine plant.

The final report is available here.