A different kind of truck stop is coming soon to Atlanta. Greg Roche, vice president for infrastructure at Clean Energy Fuels, is presently scouting locations to build one of the California-based company's natural gas fueling stations for long-haul trucks by the end of this year. With fracking techniques freeing more and more natural gas in the U.S., the alternative fuel is suddenly much cheaper than those made from petroleum.
"A trucker can save one third of his energy spend by switching to natural gas," Roche notes, thanks to the historically low prices for the gaseous fuel occasioned by the boom in U.S. shale gas development via hydraulic fracturing. "It's also good for the environment because it's the cleanest fuel available for big-rig trucks."
Clean Energy Fuels already operates six fueling stations dispensing liquefied natural gas (LNG) to the big trucks that ply the nation's highways, ranging from San Diego to Seville, Ohio. Truck stops that pump LNG can be distinguished by their tall, thin storage silos—capable of keeping up to 68,000 liters of this fuel at low temperatures and high pressures. The LNG, trucked in from big liquefying plants much like diesel fuel is trucked in from refineries, then powers the trucks over hundreds of kilometers. Such a station in the port of Long Beach, Calif., already can handle 1,200 trucks a day.
"Trucks that you're making here at this plant run on natural gas, and that makes them quieter, it makes them better for the environment, it makes them cheaper to fill up," President Barack Obama said during a March 7 speech to announce his administration's expanded alternative vehicle efforts at a Daimler truck factory in North Carolina. "But, at the end of the day, it doesn't matter how much natural gas or flex-fuel or electric vehicles you have if there's no place to charge them up or fill them up."
That's the problem Clean Energy Fuels hopes to solve with "America's Natural Gas Highway," a bid to build more than 150 fuel stations from "coast to coast and border to border," as Roche says, at a cost of $1.2 million or more per station. "The competition is for people to keep doing what they've always done and keep using expensive foreign oil."
Big rigs running on diesel fuel can cover roughly 1,900 kilometers between pit stops. Liquefied natural gas is the only other fuel that can begin to approach that kind of range, enabling truckers to cover more than 1,200 kilometers before refueling. Depending on the cost of diesel, switching to natural gas can save as much as $2 per gallon of fuel. That means the additional roughly $30,000 cost of natural gas trucks can be paid back in two years or less (assuming the trucks cover more than 95,000 kilometers a year).
At present, although the Daimler truck factory has built more than 1,000 natural gas-fueled trucks, engine options from the major truck manufacturers are limited. "Building a natural gas engine isn't that difficult," argues physicist Nicholas Cizek, a fellow at the Advanced Research Projects Agency–Energy (ARPA–E) who has worked on its Methane Opportunities for Vehicular Energy, or MOVE, project.
In fact, natural gas vehicles of all types are already popular in countries such as Argentina, India and Italy, among others. All told there are more than 13 million natural gas vehicles on the road worldwide. Gasoline taxes typically are used by national governments to promote the use of the alternative fuel. The idea is that natural gas, because it burns more cleanly than other liquid fuels and emits less carbon dioxide, reduces overall greenhouse gas emissions and other air pollution. In fact, Argonne National Laboratory estimates that natural gas vehicles emit 40 percent less CO2 than those that burn gasoline (pdf). But methane, the primary molecule in natural gas, is itself a potent greenhouse gas, and some studies have found that if significant amounts of unburned methane leak, whether during drilling, piping or fueling of natural gas, its emissions benefits may trickle down to none.