As an alternative to diesel fuel, natural gas holds much promise as a cleaner source of energy for power-hungry, heavy duty trucks and vehicles. Converting these vehicles from diesel to natural gas lowers greenhouse gas (GHG) emissions by at least 20 percent.

Now an even stronger case for natural gas is emerging from a new R&D partnership involving experts at the University of British Columbia (UBC) and the University of Toronto, along with engineers at Westport Innovations Inc. of Vancouver. Supported by a $500,000 commitment from APC, the five-year partnership aims to reinforce Westport's coveted position as a world leader in shifting the commercial engine industry from oil-based to gaseous fuels.

"Emissions regulations, especially those dealing with particulate matter [PM] and NOx [nitrous oxides], are becoming increasingly stringent, so we have to be much more innovative in ways that bring those emissions down," explains Dr. Sandeep Munshi, Westport's senior scientist for engine research.

Emissions reduction is challenging, Munshi adds, primarily due to the additional cost of exhaust aftertreatment systems. As these modular systems grow in size and complexity, they tend to penalize fuel efficiency because they operate on the same fuel that powers the heavy duty engine.

The goal of the R&D partnership is to curb emissions right at the source—within the combustion chamber—in order to simplify and reduce the costs of exhaust aftertreatment systems. If successful, Westport will be able to lower PM and NOx emissions below European and North American standards without sacrificing fuel efficiency, giving it a distinct market advantage over competitors.

The UBC researchers, led by Dr. Steven Rogak, will be aided by Dr. Murray Thompson, a combustion expert at the University of Toronto. The team will experiment with Westport's high-pressure, direct-injection (HPDI) natural gas technology in the Single Cylinder Research Engine (SCRE) test cell at UBC, established by the university and the company in 2001.

Although the project will focus on HPDI techniques for a heavy duty, six-cylinder, 15-litre engine, the experiments will be conducted on a single cylinder version of the engine. Munshi says this approach will yield greater consistency in the research findings, while providing scientists with great control and flexibility in their investigations, including the testing of fuel injection strategies and unconventional combustion techniques.

From the experiments, the researchers hope to answer some fundamental questions about natural gas combustion and identify engine hardware and operating parameters to achieve very low emissions over a wide array of conditions.

"The research we are undertaking is time-consuming and expensive," observes Munshi. Obtaining cost-sharing support from APC definitely makes it more appealing for a company like Westport to invest in this kind of longer term research. What I really like about APC is its strong focus on industry needs."