The model-year 2018 Cummins Westport B6.7N natural gas engine for school bus applications meet the lowest optional standards for oxides of nitrogen (NOx) emission, the company announced.
The California Air Resources Board (CARB) certified the B6.7N engine to the agency’s optional Low NOx standard of 0.1 g/bhp-hr, which is a 50-percent reduction from the U.S. Environmental Protection Agency’s standard.
Cummins Westport said the latest the B6.7N is based on the ISB6.7 G natural gas engine and offers between 200 and 240 hp as well as 560 pounds per foot of torque for the school bus industry.
EPA and CARB also certified the L9N natural gas engine to the optional Low NOx standard of 0.02 g/bhp-hr for medium-duty truck and refuse applications. The new certification means vehicles equipped with this engine will emit 90 percent less NOx than engines that meet the current EPA NOx limit of 0.02 g/bhp-hr.
Cummins Westport added that both engines will be available as a first-fit option from truck and bus manufacturer, come in CNG, LNG or RNG configurations and feature a new engine control module with improved durability and on-board diagnostic capability. The engines also come with an enhanced and maintenance-free, three-way catalyst and a closed crankcase ventilation system. Rob Neitzke, president of Cummins Westport, said customers can expect increased reliability in addition to near-zero emissions.
“Natural gas engines are a mature technology and are supported by an established fueling and supply infrastructure, enabling fleets to incorporate near-zero emissions technology into their fleets,” he added. “Cummins Westport’s new 2018 products mean our customers can choose the most affordable path to zero-equivalent emissions with no commercial constraints on supply or technology readiness.”
The Gas Technology Institute, the South Coast Air Quality Management District, SoCalGas and the California Energy Commission helped fund engine development, Cummins Westport said.