It's a Gas: The Powerful Argument for CNG and LNG 18-Wheelers

Jim Motavalli

Jim Motavalli | Aug 23, 2012

Let’s face it, a tractor-trailer running on natural gas looks exactly the same as a rig guzzling diesel, so you may be missing a quiet revolution. America’s truck fleet owners, motivated as much by saving money as reducing their carbon footprints, are switching to natural gas. And why not, when the savings are up to $2 a gallon, the payback can be as little as a year.

Nearly 40 percent of new garbage trucks are natural gas powered. (Waste Management photo)
Nearly 40 percent of new garbage trucks are natural gas powered. (Waste Management photo)

Let’s do the math: Diesel is up above $4 a gallon in some markets, and a gallon equivalent of natural gas ranges from $1.89 to $3. The arithmetic works because long-distance trucks are on the road all the time. And at approximately six miles per gallon, an average rig uses something like 20,000 gallons of diesel in a year. So with savings of $2 a gallon the savings on just that one truck is $40,000 per year. The more you drive, the more you save.

I’m not saying the whole fleet will change overnight. The big obstacle is filling stations—there aren’t enough of them. We have 160,000 gas stations in America, and only about 500 public natural gas stations. Fewer still dispense liquefied natural gas (LNG), which is what gives the most range in big trucks. So far, natural gas infrastructure exists in pockets around America, such as a corridor around Los Angeles.

Of course, natural gas is a fossil fuel, so we’re not out of the woods if we burn it in trucks. And the reason it’s cheap is because of the highly controversial process of fracking, which critics are saying is polluting groundwater across America. Using natural gas reduces sulfur dioxide and nitrogen oxide emissions, though carbon monoxide goes up.

President Obama visited a UPS natural gas station in Las Vegas earlier this year to highlight his support for LNG corridors, including one connecting Vegas and LA (hauling casino profits!). UPS’ station was built by Clean Energy, which wants to have 70 fueling stations (many of them at Pilot-Flying J Travel Centers along interstates) open in 33 states by the end of this year.  “As demand increases” it wants to be dispensing 340,000 gallons of LNG daily. But that’s as demand increases. This is classic chicken-and-egg—the demand has to be there before the stations open up. And the case for LNG has to be so compelling that it shakes diesel-focused fleet managers out of their routines. Fortunately, it is.

Ryder has turned natural gas into a "full-blown strategic initiative." (Ryder photo)
Ryder has turned natural gas into a "full-blown strategic initiative." (Ryder photo)

Scott Perry, a vice president at truck rental and leasing company Ryder, told me that natural gas has grown from a one-location pilot project to “a full-blown strategic initiative,” deployed in multiple regions. “The first step was Southern California a year ago, but now we have more than 200 CNG and LNG tractors, Freightliners and Peterbilts, on the road and are expanding into Arizona, Michigan and, before the end of the year, Northern California.”

The strategy, according to Perry, is to rent trucks to customers so they can see how they work, then convert the rentals into long-term leases. The main adjustment fleets have to make is to natural gas’ lower energy content—that means more frequent stops for drivers. Perry also said that not all CNG/LNG stations are created equal: “There’s a difference between fueling up a Honda Civic CNG car that takes the equivalent of 12 gallons and a big trailer that needs 700 to 900 gallons—the stations need a significant investment in storage and compression technology,” Perry said.

Perry said that Ryder’s natural gas lease customers will “realize savings right out of the gate” because of much lower fuel bills. He estimated that a typical truck might use 900 gallons a month, and save $1.354.

Ryder is hardly alone in switching to natural gas. Consider these developments:

UPS now has 920 CNG vehicles in the U.S., and 93 LNG trailers. In Canada, 912 trucks run on propane. Steve Leffin, UPS’ director of global sustainability, told me, “LNG has some challenges, but the cost of the vehicles is going down, and the fuel is becoming more available. We have a route in the Los Angeles area that’s able to make use of the fueling corridor there.” UPS is less sanguine about biofuels, and has 44 package cars running ethanol.

UPS has 93 tractors running LNG in the U.S., 920 on CNG. (UPS photo)
UPS has 93 tractors running LNG in the U.S., 920 on CNG. (UPS photo)

In April, Frito-Lay announced it was adding 67 CNG trucks, and said that eventually a majority of its long-distance fleet will run on either CNG or LNG. Annual savings are estimated as 900,000 diesel gallons annually. Frito-Lay told me that it replaces 125 trailers a year, and it’s going to deploy natural gas replacements as often as it can.

According to Natural Gas Vehicles for America, a quarter of new transit buses and nearly 40 percent of new trash trucks are natural gas-capable.

Despite all this, inertia (diesel is how we move freight in America) and the infrastructure obstacles still loom large. Bill Graves, president of the American Trucking Association, told the Wall Street Journal, a natural gas-dominated fleet is “going to be pretty slow in coming.”

The good news is that we won’t need hundreds of thousands of LNG stations to make long-distance natural gas trucking work. Andrew Littlefair, the CEO of Clean Energy, told me that instead we need “hundreds in the right places”—and that means along the nation’s trucking corridors. A map provided by his company showed there’s just over 90 of them now, with concentrations in Texas and California. Obama’s plan calls for 150 to make a national natural gas highway, so if we’re not there yet we’re at least on the way.

Andrew Littlefair, president and chief executive of Clean Energy, said that the aim was to make natural gas refueling available on the major trucking corridors. “You don’t need 23,000 truck stops with natural gas,” he said. “You need hundreds in the right places and you can move a lot of fuel." These stations will be where the trucks go now, and the economics look very good. Here's some useful video about how truck drivers are reacting to natural gas trucks:

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