Shell Oil knows how to liquefy natural gas for import and export. With North American shippers looking for relief from high diesel fuel costs, the company is seriously exploring infrastructure projects to put LNG in the trucker's tank.
James Burns, Shell's general manager for LNG for Transport, is developing relationships and logistics for a Green Corridor in western Canada that would make the fueling stations available for over the road truckers driving LNG-powered diesels. The project has quietly taken shape with the cooperation of a number of Flying J stations.
Burns says the corridor is an example of what can be done in areas with plentiful natural gas supplies. It's also the first fruits of what Shell anticipates for the Boston-NYC-Washington corridor near the Marcellus Shale formation. He says LNG fueling is a real possibility here in the Northeast in the near future.
While most proponents of natural gas for transport fuel concentrate on compressed natural gas (CNG), Shell has cast its lot with LNG. It requires no high-pressure tanks and compressors, and provides better energy density in "diesel equivalent" amounts of fuel required for long-distance travel.
Burns says on a DE basis, LNG costs about 70% of diesel fuel's price. But he acknowledges that an LNG truck is likely to cost 50% or more than a traditional diesel upfront. "When you consider LNG is non-corrosive and creates very few engine deposits, and it's a low-carbon emission fuel, we think there's room for it regardless of the higher cost of the equipment to burn it."
LNG is natural gas that's super cooled to -260 degrees Fahrenheit, and stored in insulated, non-pressurized tanks. The cooling process reduces the volume of the energy-rich fuel to 1/600th of its gaseous state.
Compressed natural gas, however, requires high-pressure-capable fuel tanks and compressors capable of squeezing the gas into the tanks at 3,500 psi. About 28 gallons of LNG would run a tractor-trailer rig about 100 miles. It would take 58 gallons of CNG to go the same distance.
Either way, a lot more fuel storage would have to be designed into the truck, Burns says. "To travel that same distance would require only about 15 gallons of diesel fuel."
Overall, the carbon emissions from LNG (from well head to truck wheel) are about 80% of that of a traditional diesel-powered rig. "LNG is the fuel of the future, and it's here now," Burns contends, and it's cheap.