Tomorrow, President Barack Obama will announce a new national fuel economy and emissions policy that incorporates California's contested plan to curb greenhouse gas emissions on its own, apart from federal government regulations. The new policy hasn't been formally released, but it has the backing of the automotive industry and politicians, and it won’t allow states to author separate rules in the future.
According to reports, fleet mileage for cars will have to average 42 mpg, and trucks will have to average 26 mpg by 2016. It's not clear if these numbers are to be based on EPA averages — what's printed on a car's window sticker — or CAFE standards. We'd assume it’s CAFE standards, given only one car on the market — the 2010 Toyota Prius — already achieves these ratings according to the EPA. For example, the Toyota Corolla has a CAFE rating of 40 mpg, but a combined EPA rating of 30 mpg. That’s because the CAFE system allows room for lots of loopholes, like highly inflated ratings for alternative-fuel vehicles.
It takes automakers years to develop new engines and transmissions, and last summer's gas price spike undoubtedly got every manufacturer rethinking what goes under the hood regardless of any government rules. If the best-selling Corolla — redesigned in 2008 — still falls shy of the 42 mpg number, even Toyota will have to upgrade every vehicle in its lineup … except for the Prius.
U.S. to Issue Tougher Fuel Standards for Automobiles (New York Times)