Improved Canadian Technologies
There are three types of technologies sold by Canadian companies for use in natural gas vehicles. Two of the three technologies are engine products that are sold directly to truck and bus manufacturers. The manufacturers integrate the natural gas engines into vehicles produced at the factory. The third type of technology is an aftermarket solution for converting passenger vehicles.
||Spark ignited 8.9 litre engine – dedicated natural gas
||Medium- and heavy-duty highway tractor, truck, bus
||Compression cycle 15 litre dedicated engine system – dedicated natural gas with diesel pilot ignition
||Heavy-duty highway tractor
||Sequential fuel injection conversion kit technology – bi-fuel natural gas/gasoline
||Passenger car, pickup, van
Better Engines for Buses and Trucks
The first natural gas engine for heavy vehicles was developed in 1985 for use in the Hamilton Street Railway transit buses. Since that time there have been significant improvements in subsequent generations of natural gas engine technology. The current Cummins Westport 8.9 litre engine shown above has power and performance characteristics similar to a comparable diesel engine but with up to 20% lower lifecycle carbon emissions. Fuel efficiency has also improved significantly. More than 25,000 natural gas engines from Cummins Westport are use around the world with refuse trucks and transit buses being the two leading applications. Cummins Westport also recently announced that it will bring an11.9 litre engine to market by 2013.
Commercial Heavy Engines
Westport Innovations’ 15 litre natural gas engine is integrated into highway tractors built by truck manufacturers Kenworth and Peterbilt. This technology was commercialized and certified to U.S. Environmental Protection Agency and California Air Resources Board standards in 2007. The Westport technology was developed based on the original research conducted by Dr. Philip Hill at the University of British Columbia. In the 1980’s, Dr. Hill’s work focused on reducing harmful nitrogen oxide and particulate matter emissions while maintaining heavy diesel engine performance and efficiency. He experimented with injecting a small amount of diesel fuel into a heavy diesel engine to trigger combustion followed by a main injection of natural gas. The development of a unique two-phase injector was part of this work and represented a key technology breakthrough. Today the Westport high pressure direct injection GX technology is the only natural gas engine technology that achieves diesel engine efficiency. This technology was recently certified to 2010 emission standards and provides up to 25% lower lifecycle carbon emissions.
Advanced Conversion Technology for Passenger Vehicles
Conversion kits are the the main type of technology used for the estimated 11 million natural gas vehicles around the world. Typical conversion kits allow gasoline vehicles to be modified so that they can be operated on gasoline or on natural gas (bi-fuel vehicle). Conversion kits that modify the original vehicle for dedicated natural gas operation also exist, but they are not commonly used in Canada at this time.
Major improvements in conversion technology mean that performance issues associated with early generation technology such as cold start concerns and loss of power are no longer a problem. Current generation technology incorporates sequential fuel injection and sophisticated electronics that control a range of functions and monitor engine temperature so that natural gas is introduced only after the engine has reached the desired temperature. In 2006, Canadian company ECO Fuels demonstrated the ability of its conversion kit technology to meet emissions threshold limits required by Onboard Diagnostics II systems. This work was carried out with funding assistance from Natural Resources Canada under the direction of CNGVA Technical Advisor Dr. Alex Lawson.