Science Scene - NG Trucks

An 18-wheeler can burn as much fuel in a year as 40 cars. What if it burned domestic natural gas instead of imported oil? 

That is hardly as arresting a vision of America's energy future as electric cars, whose power could conceivably could come from the wind or the sun. 


The typical semi-trailer truck guzzles 20,000 gallons of diesel annually and uses the same roads day after day. So switching trucks to natural gas from diesel, which comes from oil, could make a big dent in U.S. petroleum use. And it wouldn't require building nearly as many new fueling stations as switching America's roughly 240 million cars and light trucks to something other than oil. 

An 18-wheeler can burn as much fuel in a year as 40 cars. What if it burned domestic natural gas instead of imported oil? The typical semi-trailer truck guzzles 20,000 gallons of diesel annually and uses the same roads day after day. So switching trucks to natural gas from diesel, which comes from oil, could make a big dent in U.S. petroleum use. And it wouldn't require building nearly as many new fueling stations as switching America's roughly 240 million cars and light trucks to something other than oil.


Exact figures for the number of natural-gas vehicles on the road are hard to come by, but it is estimated that 15% of U.S. buses and trash trucks run on natural gas.

Trucks configured to burn natural gas cost more than trucks that run on diesel. They need modified engines and bigger and stronger fuel tanks. How much more they cost differs wildly depending on the type of truck.
A trash truck that costs $200,000 outfitted for diesel costs only another $10,000—or 5% more— equipped for natural gas.

Long-haul trucks present a bigger challenge. In the U.S., they consume about 10 times as much diesel as trash trucks and buses combined. The biggest guzzlers are 18-wheelers, which average six miles per gallon. 

United Parcel Service Inc., which runs one of the country's biggest truck fleets, pays about $95,000 for an average long-haul "tractor"—the front part of the 18-wheeler, housing the engine and driver. It recently ordered 48 natural-gas versions at a cost of $195,000 apiece—about double the cost of a diesel model.

UPS bought its natural-gas trucks only after getting $4 million in federal stimulus money to help defray the cost. At current fuel prices, the trucks should easily pay for themselves in less than the 10 years UPS expects to drive them, he says. But UPS typically expects equipment to pay off within three years.

If America could affordably manufacture natural-gas trucks and build enough fueling stations to keep them on the road, the economy could shave billions of dollars a year in imported-fuel bills, backers of the technology say. 


Lets hope that the subsidies keep rolling.