The Government's Scary New 54.5 MPG Fuel Economy Standard Is Really More Like 40 MPG

Numerous headlines this afternoon are blaring the Obama Administration's strict new corporate average fuel economy standard for 2025. Car companies, the administration says, will have to average 54.5 mpg.

That might seem impossible to anyone who remembers gas guzzlers from the 1970s that barely made it into the teens, or to Hummer owners to whom a $100 fill-up was practically a weekly event.

Truth be told, your car won't have to get 54 mpg. To reach that magic Corporate Average Fuel Economy level (CAFE) 40 mpg. Why? Because fuel economy window stickers and the fleet average are calculated in two different ways. There's been lots written about this, in places like Edmunds and Scientific American. But here's the short version:

CAFE mpg is based on a set of tests — city cycle and highway cycle — that were put in place back when the government began requiring car company fleets to achieve an average level. But window sticker fuel economy is based on a series of five tests, including hot weather, cold weather, air conditioning use, and driving at higher speeds. I went to an EPA press conference at their lab in Ann Arbor a few years ago where they painstakingly explained this all to us. (It reminded me why I didn't get a master's degree in science.)

Window sticker fuel economy has always been lower than the overall CAFE standard. According to Edmunds, the 34.1 mpg CAFE target for 2016 is actually equal to only 26 mpg on a window sticker. And, it says the 2025 standard is probably more like 36 mpg.

If you factor in vehicles like the Nissan Leaf, plus Toyota Prius and other hybrids, The New York Times says the number is probably going to be closer to 40 mpg, assuming Americans buy more of them 13 years from now.

Now, that's still high, but 13 years is a long time. These new Obama standards could get delayed by a Romney administration, or we could have another big war, or there might even be a technology breakthrough that prompts a future administration to aim for even higher standards.

And then there are carbon offsets the companies can apply from other years...

So, don't bet the farm just yet on 54.5 mpg.

Photo Credit: Getty Images