Related: CNG: From an Idea to a Solution
Researchers to Develop Low-NOx NG Engines for California
UK-based Ricardo Inc. says it will partner with the Gas Technology Institute to design the engines to emit fewer NOx emissions while powering medium-duty commercial vehicles.

A pair of private research organizations will develop natural gas engines as viable, fuel-efficient and less polluting alternatives to diesels for use in California. UK-based Ricardo Inc. says it will partner with the Gas Technology Institute (GTI) to design the engines to emit fewer oxides of nitrogen while powering medium-duty commercial vehicles.
Two Ricardo-GTI projects, co-funded by Southern California Gas Co., will aim to reduce NOx emissions from truck engines, helping attain NOx emission levels that surpass California Air Resources Board’s goals, consume less fuel than current diesels, and provide higher engine performance with the current reliability, a Recardo announcement said.
In one project, Ricardo will support development and testing of advanced ignition systems – high frequency discharge and pulsed nano plasma – as part of GTI’s collaboration with the California Energy Commission. Ricardo will test the systems so their effect on engine performance can be measured and evaluated.
In addition to Ricardo and SoCalGas, GTI’s other partners on this project include Power Solutions International, Inc. and EnerPulse Technologies Inc.
In the second project, sponsored by the South Coast Air Quality Management District,.Ricardo and GTI will develop an ultra-low emission natural gas engine for on-road Class 4-7 medium-duty trucks.
These diesel trrucks are currently among the top 10 sources of NOx emissions in California’s South Coast Air Basin, authorities say, and are projected to remain one of the largest, even as older and higher polluting trucks are replaced by vehicles meeting 2010 emissions standards.
The aim is to meet federal ambient air quality standards in coming years, the announcement said. Such ultra-low emission natural gas engines would cut NOx by 90% compared to now. They would approach levels from equivalent all-electric vehicles, when the emissions associated with electricity production are taken into account.
“Medium and heavy-duty trucks are an essential part of the transportation mix in California,” said Ricardo’s president, Clive Wotton, “but they are also significant contributors to total NOx emissions. Trucks such as these are not as amenable to the type of electrification and hybridization approaches that have been applied very successfully in the passenger car and SUV sector.
“However,” he said, “the substitution of diesel with natural gas as a transportation fuel for these classes of vehicle offers some attractive potential benefits in reducing NOx emissions.”
In addition to Ricardo and SoCalGas, GTI’s other partners on this project include Power Solutions International, Inc. and EnerPulse Technologies Inc.
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