As carmakers labor to meet tougher Corporate Average Fuel Economy (CAFE) standards for 2025, Federal regulators have turned their attention to commercial vehicles.

The U.S. Environmental Protection Agency has proposed standards that would improve the efficiency of a wide variety of vehicle classes--from large pickup trucks to 18-wheelers.

Boosting fuel efficiency often raises the price of new vehicles, however, and that can cut into operators' bottom lines.

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Yet two industry groups believe fleet operators should show enthusiasm for more fuel-efficient vehicles--and that in fact they already are doing so.

Calstart--a group advocating for greener transportation technologies--conducted a study on truck fuel efficiency, together with the National Association of Fleet Administrators (NAFA).

The study found that fleet operators will ultimately save money--thanks to lower fuel costs--and that many are in favor of stricter fuel-economy standards.

Daimler Trucks North America SuperTruck

Daimler Trucks North America SuperTruck

In fact, it found that 87 percent of fleet operators surveyed would support more aggressive regulations on truck fuel economy.

In addition, 89 percent said they would be willing to pay a higher upfront cost for a more-efficient vehicle, as long as there would be cost savings over the life of the vehicle.

The figures show that to be largely the case.

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Researchers assumed a mandated increase in fuel economy of 40 percent for medium- and heavy-duty trucks compared to 1990 levels by 2025.

They found that the largest heavy-duty trucks--big rigs covering an average 125,000 miles per year--would see the quickest payoff.

Increasing fuel efficiency could save $20,000 per year, while the extra cost of a more-efficient truck could be paid off in as little as nine months, the study found.

2015 Chevrolet Silverado HD

2015 Chevrolet Silverado HD

Vehicles covering fewer miles annually would take longer to pay off.

Researchers determined that a 1-ton pickup truck--such as a Chevrolet Silverado 3500, Ford F-350, or Ram 3500--could accrue $1,570 in annual fuel savings.

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With an estimated 25,000 miles per year covered in work service, it would take 1.1 years to pay off the premium for that more-efficient vehicle.

"Utility" trucks that spend more time idling at worksites that covering mileage could save owners up to $9,000 per year on fuel, and pay off in an average 3.5 years.

Natural Gas-powered Kenworth truck (Image: Flickr user TruckPR)

Natural Gas-powered Kenworth truck (Image: Flickr user TruckPR)

This class of vehicle was found to be the best for applications of plug-in hybrid powertrains, or other setups that allow the internal-combustion engine to be shut down while the vehicle is idling.

Lighter-duty gasoline pickup trucks and vans could yield fuel savings of $1,600 per year, and a payback period of 1.3 years.

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Because they spend more time in use than the average passenger car, with much worse fuel economy, large trucks account for a disproportionate share of transportation emissions.

While they represent a relatively small percentage of vehicles on the road, Calstart says medium and heavy-duty trucks are together make up the second-largest contributor to greenhouse-gas emissions in the transportation sector.


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