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CWI ISL-G Natural Gas Engine Certified to Near Zero Emissions

Cummins Westport (CWI) announced the new ISL G Near Zero (NZ) NOx natural gas engine has received emission certifications from both U.S. Environmental Protection Agency (EPA) and California Air Resources Board (CARB) that meet the 0.02 g/bhp-hr optional Near Zero NOx Emissions standards for medium-duty truck, urban bus, school bus and refuse applications.

Cummins Westport ISL G NZ exhaust emissions will be 90 percent lower than the current EPA NOx limit of 0.2 g/bhp-hr and also meet the 2017 EPA greenhouse gas emission requirements. CWI natural gas engines have met the 2010 EPA standard for particulate matter (0.01 g/bhp-hr) since 2001.

Since it was first introduced in 2007, the ISL G 8.9 liter engine has been a leading engine for transit buses, refuse trucks and urban delivery trucks.  ISL G NZ meets the CARB certification 8 years in advance of the 2023 California Near Zero NOx schedule contributing to California Clean Air initiatives.  CARB has defined this certified Near Zero emission level as equivalent to a 100 percent battery truck using electricity from a modern combined cycle natural gas power plant.

“This, combined with the reliability and operating improvements on the base ISL G engine, puts CWI natural gas engines at the forefront of cost-effective and dependable emission reduction strategies in transit, medium-duty truck and refuse applications,” said Rob Neitzke, President of Cummins Westport.

In addition to the 90 percent reduction in NOx, the ISL G NZ will feature Closed Crankcase Ventilation (CCV) reducing engine related methane emissions by 70 percent. Emissions are further lowered by using the maintenance-free Three Way Catalyst (TWC) aftertreatment system.

“In Southern California, clean, zero- and near-zero emission vehicle technologies are critical to meeting clean air standards,” said Barry Wallerstein, executive officer for the South Coast Air Quality Management District. “Cummins Westport’s new engine provides an important tool toward reaching that goal.”

Production of the ISL G NZ is expected to begin in April 2016 and the engine will be made available as a first fit engine with transit and refuse OEMs, and as an engine replacement for existing ISL G vehicles. Performance and efficiency will match the current ISL G, with engine ratings from 250-320 horsepower, and 660-1,000 lb-ft torque available.