Sector: CNG

Cummins Westport moves to zero

Cummins Westport Inc. took the opportunity of the annual ACT Expo exhibition in Long Beach, California, to present a new family of clean combustion engines running on natural gas. Expect an array of future heavy duty vehicles to feature them.
Assembly of the Cummins Westport ISL-G engine at the Rocky Mount facility© Cummins WestportMethane is so clean and so abundant that going the EV path doesn't exactly make sense for now

The newly unveiled units, destined for use on school buses, refuse collection vehicles and distribution as well as long-haul heavy duty trucks, bear new designations, in line with Cummins Westport's nomenclature system. B, L and X letters are used to indicate series, numbers denote displacement and the letter N at the end points to the fact that natural gas is the fuel.

The newly presented engines are: B6.7N, L9N and ISX12N. They are all EPA- and CARB-certified (EPA is the US Environmental Protection Agency, while CARB is the California Air Resources Board), while a low NOX certification is available as an option. The units feature OBD, CCV (Closed Crankcase Ventilation) and systems boosting performance and efficiency. The latest version of the ISX12N has been equipped with a redesigned fuel system, now comprising fewer parts.

The L9N replaces the previously offered ISL G Near Zero unit. Together with the ISX12N, the L9N is supposed to be among the cleanest engines offered in North America as far as NOX emissions are concerned. Both units emit by 90% less nitrogen oxides than required by EPA limits (0,2 g/bhp-hr). In terms of particulate matter emissions, Cummins Westport's engines have complied with EPA's standards and limits introduced in 2010 (0,01 g/bhp-hr) since the year 2001.

All of CWI's methane engines can run on compressed natural gas (CNG), liquefied natural gas (LNG) or renewable biogas. The fuel system uses spark ignition, stoichiometric air-fuel mixture and exhaust gas recirculation. Exhaust gasses are treated in a maintenance-free three-way catalytic converter. CWI's methane engines require no particulate matter filters or SCR (selective catalytic reduction) systems, unlike their diesel-powered counterparts.

Our 2018 product line demonstrates an important milestone in product development for Cummins Westport, creating a move to zero emissions strategy for our customers and industry. We are particularly pleased that the ISX12N will join the L9N in offering our on-highway customers the benefits of performance and reliability at an ultra low emissions level described by California’s South Coast Air Quality Management District as equivalent to an electric vehicle.  This move to zero emissions strategy means our customers can choose the most affordable path to zero-equivalent emissions with no commercial constraints on supply or technology readiness.

Rob Neitzke, President of Cummins Westport

The ISX12N unit will be produced at the Cummins engine facility in Jamestown, New York, while the L9N will be assembled at the Rocky Mount factory in North Carolina. Development of the ISX12N was partially funded by the South Coast Air Quality Management District, the California Energy Commission, Southern California Gas and Clean Energy.


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Piotr Złoty
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