I knew no good would come of cheap gas. In addition to depressing sales at high-end boutiques in oil towns like Dallas, $2 a gallon fuel has Americans (rather predictably) moving back into big trucks and SUVs, and consequently using more fuel.

What’s that mean? Unfortunately, it makes it hard for automakers — who, after all, sell what people want to buy — to meet the huge 2025 Corporate Average Fuel Economy (CAFE) goal of a 54.5 mpg fleet average. And an Environmental Protection Agency midterm review in 2017 could roll back that important milestone.

Gloria Bergquist, a spokeswoman for the Auto Alliance, which represents 12 automakers, says the review will compare the regulatory assumptions in the rule with this new reality. “One concern,” she said, “is that sales of our most fuel-efficient vehicles tracks very closely with the price of gasoline, and while we don’t wish high gas prices on anyone, pain at the pump does sell more of our most fuel-efficient cars.”

SUV ignoring the parking rule

How many times have you seen something like this: SUVs ignoring the rules? (Photo: Cory Doctorow/flickr)

If they care about this, environmentalists are going to have to be vigilant about how the CAFE numbers are adjusted. Dan Becker, director of the Washington-based Safe Climate Campaign, raises a good question: why ruin a program that’s already effective? “New auto emissions standards have improved mileage by 5 mpg so far, cutting demand for gas and helping lower gas prices and pollution levels,” he said. “Now automakers want to kill the goose that lays that golden egg. That’s poor payback for saving their tailpipes with an $85 billion bailout.” 

On the other hand, carmakers didn’t oppose the tough CAFE rules, finalized in 2012. As the Washington Post pointed out, they were embraced by “industry and environmentalists alike.”  The industry may be maneuvering behind the scenes, but Bergquist asserts that “automakers now have 483 models that achieve 30 mpg or more on the highway, up six times from what was available in 2006. Automakers have invested heavily in many fuel-efficient technologies and have a big stake in selling them in high volumes.”

People buy SUVs because they

People buy SUVs because they "like to sit up high." (Photo: Justin S. Campbell/flickr)

So what’s likely is a readjustment of 54.5, but probably not some huge retreat from it. The march to saving gas — with technology like small engine turbo and supercharging, lightweighting with carbon fiber, cylinder deactivation, direct injection — is not likely to go away.

If gas prices stay low for a while, and they probably will, the automakers’ job is going to get harder. It already has. In the five months from June (when gas prices peaked) to February, pickup sales rose 8 percent from the same period a year earlier, and small car sales declined 1.5 percent. In 2014, Toyota Prius sales fell nearly 12 percent.

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Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.