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Vancouver Opts for 95 Cummins Westport CNG Buses

The Greater Vancouver Transportation Authority (TransLink) has selected Cummins Westport (CWI) C Gas Plus natural gas engines to power up to 95 new 40-foot, compressed natural gas (CNG) heavy-duty buses for the Greater Vancouver area.

The buses will be built by New Flyer Industries Inc. of Winnipeg and delivery of the base order, for 73 vehicles, will occur in mid-2006. This marks CWI’s first large commercial order in British Columbia, and positions CWI to showcase its latest technology at a time when TransLink is embarking on a major fleet expansion program.

C Gas Plus w/Catalyst and Various Standards
(grams per brake-horsepower-hour)
Standard Emission Limit C Gas Plus

2005 EPA
NOx+nmHC 2.5 1.8
PM 0.1 0.01
CO 15.5 1.3

2005 CARB 
NOx+nmHC 2.5 1.8
PM 0.1 0.01
2005 CARB
Optional Low NOx
NOx+nmHC 1.8 1.8
PM 0.03 0.01

Euro III
NOx+nmHC 3.73 1.8
PM 0.075 0.01
CO 15.5 0.8

The 8.3-liter lean-burn, spark-ignited C Gas Plus engines provide between 250–280 hp (187–209 kW)and develop 895–1,085 Nm of torque.

Increasingly, vendors of compressed natural gas vehicles are positioning CNG as a gateway to hydrogen. This one was of the lines of argument taken by the Enbridge-Cummins Westport-Clean Energy consortium in winning the delay of a major diesel-hybrid bus purchase in Ottawa. (Earlier post.)

That would fit nicely with British Columbia’s focus on a BC Hydrogen Highway (earlier post).

As an aside, the Ottawa city council staff who favored diesel-hybrids disputed—for a number of reasons—the premise that CNG buses smooth the pathway to hydrogen. However, they acknowledged that a competition between a diesel-hybrid and a CNG-hybrid bus would be much closer.

The consortium—Enbridge, Cummins Westport and Clean Energy—advised that CNG hybrids are in the early stages of testing, and are something that they would like to move forward with when feasible, perhaps in 2007.



So still, Mike or someone else, can you please outline the basic reasons why hybrid diesel is not better than CNG?


Hmm, let me see, i personally like both diesel and CNG. But according to the above article...

It seem like they really like the idea of hydrogen and think that CNG vehicle is a stepping stone to hydrogen and can be replaced straight away once hydrogen production is on track.

CNG Buses still have the potential of implementing a hybrid system on it, maybe further enhancing the fuel efficiency and emission.

And also, i think...

Is CNG bus maintainence lower?

USA gov guys dont like diesels.

CNG is locally available?

The guy in charge is a good friend of vendors of compressed natural gas vehicles.

tom deplume

CNG is a much cleaner fuel. Would you have a diesel fueled range in your kitchen? At $2.50 a gal diesel costs over $20 MMbtu which is 305 more than $15 nat gas.

tom deplume

CNG is a much cleaner fuel. Would you have a diesel fueled range in your kitchen? At $2.50 a gal diesel costs over $20 MMbtu which is 30% more than $15 nat gas.


no, but my kitchen doesn't carry 60+ people at speeds of 50+ mph. it cooks food.
the main concern i have with CNG is its high output of CO2 into the atmosphere. here we are talking about global warming, and at the same time touting cng as a great fuel.
there is technology out there, specifically extensive EGR and high-quality catalytic converters, which already make diesel a clean alternative. adding a hybrid drive to it greatly improves emissions and will also provide mileage gains.
there is a huge stigma surrounding diesel in the US. refusing to seriously consider hybrid diesel buses only furthers it and hinders further development in heavy-duty hybrid powertrains.


As far as I've read CNG (methane) creates much less CO2 when burned as compared to diesel. My hope is that the CNG designs can incorporate hybrid features soon so that there can be further improvement regardless of the fuel choice.


Carbon based fuels will soon be replaced by a powercell technology that produces electricity from saltwater. In the meantime, as that's being further developed and tested with NASA/JPL, a turbine fueled by cng, diesel, petrol, or vegetable oil, will kick-in to boost the batteries to drive the motor of the hybrid-electric transit bus. After a full day's running they'll be pluged in at night to the local grid, fully monitored, and ready for redeployment in the morning.

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