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CWI Near Zero NOx Emissions ISL G Natural Gas Engine

Cummins Westport (CWI) announced it will begin field tests this year in California in transit buses with a spark ignited natural gas engine capable of producing Near Zero NOx emissions well before the 2023 California Near Zero NOx schedule for Low NOx vehicles.

CWI believes its proprietary Stoichiometric EGR Spark Ignited (SESI) natural gas engine technology as released on its ISL G and ISX12 G engines is ideally suited to continue to provide an economic and efficient solution to California air quality improvement initiatives.

With funding support from South Coast Air Quality Management District (SCAQMD), SoCal Gas and California Energy Commission (CEC), CWI has recently invested significantly on leveraging the SESI platform to develop a new Near Zero NOx technology pathway to 0.02 grams per brake-horsepower hour NOx. CWI has demonstrated this technology and will now field test a transit bus with the new Cummins Westport Near Zero NOx ISL G that will reduce NOx emissions by 90 percent from the current EPA limit of 0.2 g/bhp-hr to 0.02 g/bhp-hr NOx while also meeting the 2017 EPA greenhouse gas emission requirements.

The new Near Zero NOx ISL G will continue to use the maintenance-free Three Way Catalyst (TWC) after-treatment. TWCs are effective, simple, passive devices, packaged as part of the muffler. Cummins Westport natural gas engines do not require active after-treatment such as a Diesel Particulate Filter (DPF) or Selective Catalytic Reduction (SCR). Commercial availability will be announced at a later date.