Natural Gas has come of age as a transportation fuel, offering compelling savings and a competitive advantage, according to Allen MacKinnon, a regional field service engineer, eastern North America, with Westport HD. MacKinnon presented at the Private Motor Truck Council’s annual conference this June in King City, Ont.

Westport HD-powered trucks are hauling up to 140,000 lbs with the same efficiency and reliability of diesel engines, and can be available within eight weeks for delivery in the yard, MacKinnon says.

Westport has become a global leader in medium and heavy-duty commercial vehicle engines operating on alternative fuels and is heavily focused on the transformation of markets for petroleum fuelled engines to alternate fuels.  The Vancouver-based company has invested $250 million and 20 years of development in alternate fuels. Westport is aiming for market penetration via OEM partnerships and joint ventures.

The company currently has 400 patents, 130 specific inventions and 30,000 engines.

“In trucking, natural gas has a lifecycle operating cost that is much lower than diesel, with the same horsepower, torque and fuel economy as the base diesel engine,” said MacKinnon.

On greenhouse gas emissions, natural gas has approximately a 25% well to wheel GHG.

“With downward pressure on natural gas prices, the forecast is for consistently low prices. A price differential of $1.50 between natural gas and diesel is not unheard of,” he said.

Westport is currently engaged in producing and selling technologies for all types of applications.

Its Heavy Duty 15 litre engine, for example, is based on Cummins’ ISX-

“We outfit it with all our natural gas components in Delta, B.C.,” said MacKinnon.

The ISL G engine, meanwhile, runs a three way catalyst aftertreatment, with no SCR and no DPF, said MacKinnon.

It has over 80% parts commonality with ISL 9, and is compatible with CNG, LNG, or biomethane.

The cost of maintenance related to ignition and overhead valve adjustments does add incremental maintenance cost for the ISL G versus the ISL 9, but MacKinnon said this cost is typically more than offset by fuel cost savings with natural gas.

And natural gas engines are up to 10db quieter at idle, he added.

The ISX 12G, Cummins’ next product, is set for commercial launch in first quarter of 2013. It’s currently undergoing field testing.

Westport’s heavy duty High Pressure Direct Injection (HPDI) technology, based on Cummins’ 2009 ISX engine, sees diesel fuel injected just prior to the natural gas.

A “liquid sparkplug” provides compression ignition. Natural gas is injected at high pressure at the end of a compression stroke, with no pre-mixed air/fuel, and with just 5% diesel usage.

The engine performance offers the same power and torque and the same efficiency as a diesel engine, said MacKinnon.

Westport HD’s LNG tank technology essentially “works like a Thermos,” he said.

The gas is stored as a cryogenic liquid, and the tank, with its internal hydraulic pump, pumps the liquid natural gas into the engine to run it. Each stroke turns it into compressed natural gas.

At 1-2 fuel tanks per vehicle, the additional truck cost ranges from $75-100,000, said MacKinnon.

“You have to go through more volume of the less energy-dense liquid natural gas. A 120 gallon tank has a 300 mile range of 54 g diesel gallon equivalent units (at 5.5mpg US),” he said.

In terms of volatility, MacKinnon said that the LNG tanks are in themselves extremely safe and resistant to damage.

“They are drop tested from 30 feet and cannot have leaks. The amount of compressed natural gas on board (10 litres) is also relatively small compared to the amount stored on buses,” he said.

Several fleets have made the transformation to operating natural gas trucks, said MacKinnon.

“Vedder Transport is running 50 Peterbilt LNG tractors in milk haul and regional tank operations, and in waste hauling,” he said.

Robert Transport has a 180 Peterbilt order running the Westport HD 15L engine. It also has over 60 trucks currently running with LNG fuel supplied by Gaz Metro, said MacKinnon.

Alberta-based Ferus Wellsite Cryogenics Solutions is transitioning their 80 tractor fleet to LNG, and the company expects more than 7600 tons/year reduction in emissions – equivalent to 1,300 cars, said MacKinnon.

Westport’s target customers are still the more regional or local fleets, as infrastructure for delivering natural gas is still in its infancy.

 “Westport is now investing tens of millions of dollars in support infrastructure. Shell has committed to building 200 of these fuelling stations at their truck stops over the next few years,” said MacKinnon.