EPA, CARB Certify Cummins Westport ISX12N Natural Gas Engine
Cummins Westport announced that the Environmental Protection Agency and California Air Resources Board have certified the 2018 ISX12N natural gas engine.

ISX12N Natural Gas Engine Photo: Cummins Westport

Cummins Westport announced that the Environmental Protection Agency and California Air Resources Board have certified the 2018 ISX12N natural gas engine.
The ISX12N was certified to meet CARB’s optional low NOx standard of 0.02 g/bhp-hr, a 90% reduction from engines operating at the current EPA NOx limit of 0.2 g/bhp-hr, according to CWI. The ISX12N also meets 2017 EPA greenhouse gas emission requirements.
Based on the ISX12 G, first introduced in 2013, the ISX12N natural gas engine will be available with ratings from 320 to 400 horsepower and up to 1,450 lb-ft. of peak torque. The ISX12N is designed for line haul, regional haul, refuse, and vocational trucks, as well as motorcoach and commuter buses.
Like Cummins Westport’s new L9N and B6.7N engines, the ISX12N will feature a new engine control module with improved durability, on-board diagnostics, an enhanced, maintenance-free three-way catalyst, and a closed crankcase ventilation system, according to the company.
All CWI engines offer customers the choice of using compressed natural gas, liquefied natural gas, or renewable natural gas as a fuel. RNG is pipeline-quality natural gas produced from the decomposition of organic waste, which can come from a variety of sources such as dairy farms, landfills, and urban waste treatment plants. Combining Cummins Westport’s ultra-low emission engines with RNG fuel provides additional GHG reductions, according to CWI.
“Cummins Westport’s 2018 product line offers customers ultra low emissions with reliable performance,” said Bart van Aerle, president of Cummins Westport. “The ISX12N near-zero emissions natural gas engine provides truck and bus customers with an industry-leading alternative fuel option for demanding applications.”
Production will begin in February of 2018.
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