Making the Case for Propane: From Gas Grills to Cars and Trucks

Jim Motavalli

Jim Motavalli | Nov 15, 2012

I’m sitting in a coffee shop with Roy Willis, propane advocate, who’s driven up from New York City to lobby me on using his fuel in cars and trucks, and darn if he isn’t making a compelling case. Why aren’t we using propane—the same stuff as in your backyard gas grille—in our cars? It's possible. Today's internal-combustion cars and trucks can run on CNG, LNG or propane with some fairly simple engine modifications.

Propane is gaining ground as fuel for southern police cars. (PERC photo)
Propane is gaining ground as fuel for southern police cars. (PERC photo)

Right now there are tens of thousands of propane-powered vehicles on the road, but it’s regional. There are thousands of propane refuelers, but they’re concentrated in California and Texas. Public refueling is a problem for CNG, too—there are 1,000 CNG stations, about half of which are public. Propane is proving particularly popular in Canada and in the southern U.S., where a passel of good ‘ol boy sherrifs are converting police cars—and often using confiscated crystal meth money to pay the $5,000 to $10,000 per-vehicle costs.
A spokesman for a North Carolina enforcement division, which has confiscated $170 million in drugs and $7 million in cash from dealers since 1994, told me, “With the economy the way it is, budgets are restrained, so we might use some of that money to buy vehicles one year." What would Sherrif Andy Taylor of Mayberry say about that?
Is T. Boone Pickens the villain here, as Willis, president of the Propane Education and Research Council (PERC), suggests? Do his CNG and LNG business interests blind him to the superiority of propane? “We tried to get him to fully embrace propane,” Willis said, “and include it in the proposed Natural Gas Act (NGA), but we were told it would increase the cost of the bill.” For those unfamiliar, Pickens has championed the stalled NGA, which would offer up to $5 billion in incentives to long-haul trucking firms to convert to natural gas.

Airport shuttles are embracing the propane option. (PERC photo)
Airport shuttles are embracing the propane option. (PERC photo)

Let’s make a clear distinction here—propane is distinct from compressed natural gas (CNG) and liquefied natural gas (LNG). Propane is a liquid at near-room temperature, as opposed to -260 Fahrenheit for LNG. Some 70 percent of propane is produced from natural gas, and 30 percent as a byproduct of oil refining. The natural gas method is cleaner, since refining chemicals sometimes get into propane from oil.
CNG definitely has the advantage over propane for vehicles now, though neither has a large share of the transportation market. Four of every 10 new trash trucks run on CNG, and a quarter of new transit buses. LNG has the lead in long-distance trucking—and the low cost of the fuel today is pushing a rapid transition. Honda is the only manufacturer making a CNG car for consumers, but there are many more available in Europe and elsewhere in the world. Propane has lots of applications in the third world, because it's a ubiquitous fuel globally.

Roy Willis: Advocate for cars with propane power. (Jim Motavalli photo)
Roy Willis: Advocate for cars with propane power. (Jim Motavalli photo)

Because propane requires only modest compression, at 200 to 300 pounds per square inch (psi), refueling is easier and cheaper, Willis says, requiring only a few horsepower to pump. CNG vehicles use 10 times more compression. You can buy a home propane refueler for approximately $1,500. They’re working on a CNG version at that price point, but it’s not here yet. There are some disadvantages to propane, but that's true of any transportation fuel.
PERC’s strategy is targeted more at fleets than at cars you or I might drive. Roush Clean Tech is a leading supplier of propane-powered fleet trucks, vans and school buses. You can get propane power for the same Ford F-250 truck that’s also offered through Ford dealers with bi-fuel CNG. Roush claims that one shared-ride van service is saving more than $18,000 a year per vehicle. Freightliner, a division of Daimler, is also developing propane trucks and Thomas Built school buses.
The CNG/LNG counter-argument was boiled down for me by a trade association spokesman, who asked for anonymity:

  • CNG is an all-domestic fuel, but propane from refineries is largely via foreign oil. It’s a false claim to say that propane is primarily American because of oil imports. CNG is more a domestic resource than propane.
  • Natural gas has the lead in displacing gasoline, as measured by the Department of Energy’s Clean Cities Program. CNG has displaced more gas than any other alternative fuel.
  • CNG is cleaner-burning—propane has more carbon. It’s very clean, but not as clean as CNG.
  • There are more CNG engines available right now, covering all aspects of the truck market. There is no propane engine yet that can be used in long-haul trucks.

Willis responds that CNG does have more energy BTUs per gallon equivalent, but he points to an American Petroleum Institute survey showing that propane has displaced 600 million gallons of gasoline. “CNG is used mostly in heavy-duty vehicle (metro buses, semis, trash haulers), all vehicles with poor fuel economy using more gallons per vehicle,” Willis says. “Propane is used in vehicles with better mileage, so more propane vehicles translates to fewer gallons per vehicle.”
Stephe Yborra, director of market development for natural gas vehicle trade association NGVAmerica, admits that propane has some advantages. “It’s cheaper and easier to put in a propane infrastructure,” he said. “You need a simple pump, and then the truck comes every few days and fills you up. Putting in natural gas lines and compressors is more complicated. And there’s also an advantage in fuel storage, because you can put more fuel on board and provide a larger range.” And these are exactly the reasons Willis says propane has a big advantage in terms of saving money in big fleets.
But Yborra says CNG wins on price, energy content and general availability. Is propane cheaper than CNG? It’s hard to do a direct comparison, because propane is sold in gallons and CNG in 1,000-cubic-foot measures. But there are gallon equivalents for CNG, and the prices seesaw. The CNG people claim that CNG is a bit cheaper. Willis admits that, citing $2.10 to $2.39 for a gallon of propane autogas, and $1.80 for an equivalent gallon of CNG. Complicating matters, natural gas advocates say, is the fact that a gallon of propane has fewer BTUs than a gallon of CNG gasoline.
Yborra is pretty clear on the matter. “They’re both good fuels. You save $1.50 to $2 a gallon with CNG, and maybe $1.25 to $1.50 with propane.” He also claims that propane quality varies widely across the country.
Willis sees a big market ahead for hybrid gasoline/propane cars and trucks (especially because of tough new federal fuel economy standards), and for commercial lawn mowers and generators. The disadvantages of gasoline-powered generators were made graphically clear by the photos of people standing in line with red gas cans in the wake of Hurricane Sandy.
The bottom line is that gasoline wins because it has the infrastructure—160,000 gasoline stations across the country. Propane is a fascinating and intriguing fuel. The problem here is that CNG and propane have distinct refueling stations, and building up one doesn’t help the other. If these guys could get together and pick one winner, gaining market share would be easier.

New Jersey cops also like propane power, as this video illustrates:


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