BOUCHERVILLE, Que. -- Groupe Robert is buying 180 new Petes powered by liquefied natural gas (LNG).

Robert is the country’s seventh-largest fleet, running about 1,100 trucks, and the new Peterbilts will be used on line-haul runs between Toronto, Montreal, and Quebec City.

The purchase is actually bigger than anticipated.

In the Spring, Robert made headlines by announcing his investment in LNG but at that time, he estimated that his initial investment would involve about 130 of the alternative-fuel power plants.

This larger deal was announced this week.

The engines are produced by Vancouver’s Westport Innovations, and are based on the Cummins ISX diesel-engine.

They employ 3 percent of diesel fuel at ignition; a diesel fuel pump draws and pressurizes diesel fuel from the pilot diesel tank, then both the diesel and natural gas are sent to the fuel conditioning module, where they are pressure regulated, filtered, and distributed to the fuel injectors via fuel rails.

The 15-liter engines, which deliver up to 450 hp and 1,750 lb ft of torque, will be fueled by Gaz Metro, which plans to install three refueling sites along Hw. 401.

"This is the single largest order for LNG Trucks powered by Westport HD," says Westport CEO David Demers. "It's evidence that natural gas is gaining momentum as a mainstream transportation fuel in Canada."

In order to spur sales, the Quebec government has accelerated the depreciation rate from 40 percent to 60 percent for any new trucks purchased after March 31st, 2010. An additional 85 percent cut for amortization reduction is granted if the truck or tractor runs on LNG.

Groupe Robert CEO and President Claude Robert -- who not incidentally is a chartered accountant -- explained the decision this way: "Operating natural gas trucks helps reduce one of our largest input costs and reduces our carbon footprint.

"This is a win-win for both the environment and our company."