Trucks barre along Interstate 81. (Katherine Frey/The Washington Post)

Besides making your air cleaner, the new fuel efficiency standards announced by the Obama administration won’t affect you too much unless you drive a big rig.

Or will they?

The new fuel-economy standards target 18-wheelers, buses, large pickups, delivery vans and other large vehicles in an effort to cut greenhouse gas emissions and reduce U.S. dependence on fossil fuels. When the standards go into effect, beginning with the 2021 model year, they will eventually eliminate more than 1 billion tons of carbon pollution, cut an estimated 84 billion gallons in oil consumption, and save nearly $170 billion in fuel costs.

That’s of course very good for your lungs and Planet Earth, even if you never leave your driveway — but maybe especially if you never leave your driveway.

As we become a nation of online shoppers, the fleet of vehicles that delivers all that stuff to our doors is expected to grow. Phyllis Cuttino, director of the Clean Energy Initiative at Pew Charitable Trusts, said freight tonnage is expected to nearly double in the next decade or so — up 88 percent by 2035. If present trends continue, big rigs will be hauling most of that. Yet they’re also among the least efficient vehicles on the road.

“We’re in a society where everything is being shipped to our house,” Cuttino said. “So it’s really impressive.”

Right now, the big rigs get about 6 mpg, travel 120,000 miles a year and carry about 70 percent of the nation’s freight, Cuttino said, citing tonnage figures from the American Trucking Associations. Yet, even though  the new fuel standards could add an estimated $14,000 to the cost of new trucks, the industry welcomed the standards because of the anticipated savings on fuel.

It could even mean savings for the homebound shopper— or at least little upward price pressure — because one of the biggest parts of shipping costs is fuel, Cuttino said. That’s important because online merchants can be inefficient: She noted that one recent order she received from Amazon (whose owner, Jeffrey P. Bezos, also owns The Washington Post) arrived in four shipments.

Cuttino, citing Union of Concerned Scientist calculations, said the average family spends about $1,100 a year in shipping costs. When fuel savings bring down the costs of transporting goods, the average household could save nearly $150 a year by 2030 and $275 by 2040, assuming all savings and costs are passed on to consumers, Cuttino said.

Not a bad deal.

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