Cummins Westport Inc. (CWI) announced that its new ISL G Near Zero (NZ) natural gas engine is the first mid-range engine in North America to receive emission certifications from both US Environmental Protection Agency (EPA) and Air Resources Board (ARB) in California 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% 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.
Performance and efficiency will match the current ISL G, with engine ratings from 250-320 horsepower, and 660-1,000 lb-ft torque available. Base warranty, extended coverage options, maintenance procedures and service intervals are also the same as the current ISL G. The new engine has similar emission control systems (throttle body injection, TWC, EGR, etc.) as the current 0.20 g/bhp-hr NOx ISL G.
CWI proprietary Stoichiometric EGR Spark Ignited (SESI) natural gas engine technology with TWC as released on the ISL G NZ is also applicable to CWI ISB6.7 G and ISX12 G engines, with Near Zero product plans for these engines being assessed, CWI said.
Since it was first introduced in 2007, the ISL G 8.9 liter engine has become the leading natural gas engine for transit buses, refuse trucks and urban delivery trucks, which represent a significant portion of on-highway and urban power in California. ISL G NZ meets the ARB certification 8 years in advance of the 2023 California Near Zero NOx schedule contributing to California Clean Air initiatives. ARB has defined this certified Near Zero emission level as equivalent to a 100% battery truck using electricity from a modern combined cycle natural gas power plant.
These North America emission certifications result in a game-changing reduction in urban tailpipe and engine related emissions. 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.—Rob Neitzke, President of Cummins Westport
More than 40,000 natural gas powered trucks and buses operate in North America.
The new ISL G NZ will power Near Zero emission trucks and buses at a significant discount to the cost of electric powered vehicles. In addition to the 90% reduction in NOx, the ISL G NZ will feature Closed Crankcase Ventilation (CCV) reducing engine related methane emissions by 70%.
The ISL G NZ will continue to offer customers the benefit of performance with the lowest emissions utilizing maintenance-free Three Way Catalyst (TWC) aftertreatment. TWCs are effective, simple, passive devices, packaged as part of the muffler.
Cummins Westport natural gas engines do not require active aftertreatment such as a Diesel Particulate Filter (DPF) or Selective Catalytic Reduction (SCR).
CWI acknowledged engine development funding support from South Coast Air Quality Management District (SCAQMD), SoCalGas and California Energy Commission (CEC).
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, resulting in an immediate NOx emission reduction well before the 2023 Near Zero NOx goals set in California.