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Project at a Glance

Project Status: complete

Title: Development, demonstration & commercialization of a 0.20 G/BHP-HR NOx natural gas engine

Principal Investigator / Author(s): Cummins Westport, Inc.

Contract Number: ICAT 06-08

Research Program Area: Emissions Monitoring & Control

Topic Areas: ICAT Grants / Technology


Cummins Westport commenced commercial production of the 8.9 liter ISL G natural gas engine in June, 2007, with ARB certification to the 2010 on-highway emission standard. The ISL G engine uses stoichiometric, cooled EGR, spark ignition (SESI) combustion technology in conjunction with a three way exhaust catalyst, a passive device which is highly effective at passive NOx conversion. The ISL G target markets at launch were transit buses and refuse collection trucks. Following ISL G launch, CWI and ARB executed ICAT Grant Agreement 06-08 to further develop & demonstrate the ISL G engine in medium duty truck applications, leading to factory availability from a major medium duty truck OEM. The scope of work included developing additional performance rating & hardware options to enable the ISL G engine to be installed in medium duty trucks, as well as enabling installation in a wide range of other commercial vehicle applications, including yard tractors, street sweepers, school buses, and shuttle buses. The project deliverable would be a version of the ISL G that is commercially available for use in medium duty trucks and the specialty vehicle applications identified above.

Cummins Westport has developed two additional ratings for the ISL G, and a new “low-mount” turbocharger option to enable ISL G integration in Freightliner’s popular M2 truck model. These new options became commercially available in early 2009, and are in widespread commercial use by fleet customers. Pacific Gas & Electric has operated an ISL G-powered truck in its fleet operations for approximately 12 months. Freightliner has commercialized multiple ISL Gpowered versions of its M2 truck. The OEM availability of ISL G-powered vehicles has expanded significantly during this ICAT project, and includes major vehicle manufacturers in each of the target market segments identified above.


For questions regarding this research project, including available data and progress status, contact: Research Division staff at (916) 445-0753

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