There's also likely to be an aggressive push to develop hybrids, much to the administration's liking. A new study this week by JP Morgan predicts 20 percent of the vehicles sold in the United States in 2020 will be hybrids.
And as Michael Sivak of the University of Michigan's Transportation Research Institute points out, because vehicles have gotten progressively heavier over the years with all their extra features, one way to boost fuel efficiency is to try to slim them down.
The success of these efforts will ultimately depend upon what consumers are willing to buy. The EPA says the new rule will increase car prices by $600, which the average driver should recoup in about three years from buying less gas. Assuming, that is, that Americans start buying again. This year, analysts are expecting vehicle sales of about 10 million, down from a peak of about 16 million just a few years ago.