The U.S. Environmental Protection Agency has released proposed standards that would further boost the fuel efficiency of heavy-duty trucks and buses, starting in the 2021 model year and running through 2027.

The new regulations were announced on Friday by Transportation Secretary Anthony Foxx and the EPA.

The White House cited the rules as another element in its strategy to reduce U.S. greenhouse-gas emissions at least 26 percent by 2030, compared to levels in 2005.

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Full details of the proposed rules are available on the EPA website.

For heavy-duty vans and pickup trucks, fuel economy would have to rise by 2.5 percent a year starting in 2021.

And for the first time, the EPA is including efficiency standards for trailers as well--excluding some categories, including mobile homes--starting in 2018.

Daimler Trucks North America SuperTruck

Daimler Trucks North America SuperTruck

Similar NHTSA standards would go into force in 2021, but the agency would offer credits for early participation before then.

The rules will take effect somewhat later than some analysts had expected, to give truck makers time to design, develop, engineer, and tool up for new fuel-efficiency technologies.

Medium- and heavy-duty trucks and buses are only about 5 percent of the total vehicles on U.S. roads, but they cover more miles than private cars and consume vastly more fuel per mile--accounting for 20 pecent of overall carbon emissions from transportation.

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A large truck could rise in cost as much as $14,000 to meet the new rules, the EPA said, but lower fuel costs would likely offset that in as little as two years.

Unlike some previous rounds of regulation, the trucking industry appears to support the new rules--including the American Trucking Association.

As usual, the National Automobile Dealers Association and American Truck Dealers came out with a joint statement that slammed the new regulations.

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

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

The rules are based on "potentially untested technologies" and consequently pose a "great risk" in a "still fragile economy," the statement said.

Vehicle sales last year were the highest they had been since 2006, however, and as noted, most of the new EPA rules don't take effect for seven model years.

Environmental groups applauded the proposed regulations, with Environment America, the Natural Resources Defense Council, and many others issuing statements in support.

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Fiat Chrysler Automobiles, maker of Ram trucks, issued a statement noting that a single set of national regulations were greatly preferable to individual state mandates.

That's undoubtedly a reference to California's ability to set its own emission standards.

Before 2007, the fuel efficiency of medium- and heavy-duty trucks was not regulated at all--unlike that of light-duty passenger vehicles, which had been subject to Corporate Average Fuel Economy rules for three decades.

Mack Pinnacle natural-gas powered truck

Mack Pinnacle natural-gas powered truck

The first fuel-economy standards for the larger vehicles were finalized in 2011, calling for a reduction of 10 to 20 percent in fuel consumption depending on the vehicle type.

The latest set of proposed rules for 2021 and beyond will now undergo a process of review and public comment before adoption.


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