Popular Mechanics — The automotive industry is bracing for its biggest engineering challenge in decades. The pending changes to federal Corporate Average Fuel Economy (CAFE) regulations call for a stunning 5 percent increase in fuel economy per year, culminating in a fleet average of 54.5 mpg by 2025. Common sense—and a fair amount of industry experts—would indicate that cars are about to get smaller, or at the very least stop getting bigger, and that SUVs will continue their steady decline in popularity.
According to a new paper from the University of Michigan College of Engineering, however, CAFE will likely have the opposite effect: It will lead to an increase in size for most vehicles, and more SUVs and light trucks on the road.
The researchers, whose results will be published in the January issue of the journal Energy Policy, put themselves in the shoes of carmakers designing for the 2014 model year. By weighing what they know about what cars customers want—taken from existing surveys and recent market data—against the projected costs of efficiency-boosting features and technologies, they concluded that practically every type of vehicle would get a size bump. Overall, the footprint of the entire U.S. fleet could get between 2 to 32 percent bigger, resulting in a 1 to 4 mpg drop in efficiency. In terms of emissions, that’s the equivalent of running three to 10 extra 10,000-megawatt-class coal-fired plants for a single year.
How could this be? It’s a shocking, counterintuitive prediction, which only makes sense when you wade through the tall grass of CAFE’s sordid, politically charged history. CAFE was born in 1975, a product of that era’s energy crisis. It changed shape through the decades, finding varying degrees of success in boosting average fuel economy. During an aggressive overhaul of the regulations in 2007, Congress attempted to make the regulations fair for all automakers.
At issue was this: Some companies offer full model lines, from cars to large SUVs and pickups, but some don’t. How could there be a overreaching fuel-economy standard that penalized companies like Ford and GM, while carmakers that sold only smaller cars effortlessly abided by the rules? So the concept of vehicle footprint was added. Models that ran large, crossing specific length-by-width thresholds‚ would have less ambitious fuel-economy targets. While the Obama administration has pushed for more aggressive CAFE numbers, the amended regulations retain the footprint-based leniency towards bigger cars and light trucks.
The result is a loophole, allowing the entire auto industry to sidestep some of the more painful efficiency requirements by inflating vehicle footprints. And historically, drivers almost always lean toward larger vehicles. “In general, if everything else about the vehicle is the same, consumers prefer the bigger one, with the roomier interior,” says Kate Whitefoot, a senior program officer at the National Academy of Engineering and the lead author of the paper (she was a doctoral student at the time of the study). Combine a regulatory loophole with a built-in, well-known customer choice, and the industry lurches towards the inevitable: larger models and more light trucks.
Like all things CAFE-related, it’s more complex than it first appears. What the University of Michigan study describes is not a callous attempt by car companies to subvert the intent of fuel-efficiency legislation, but the undeniable power of consumer preference. If car buyers valued fuel economy more than anything else, the story would be different. Detroit could hybridize its entire fleet, with customers happy to pay more upfront for greater fuel savings down the line.
But the research shows that sort of approach, whether it involves pricier electrified powertrains or lightweight materials such as aluminum or magnesium, could be a disaster, with buyers flocking to the cheaper competition. “Consumers need to be willing to pay for fuel economy. If automakers are forced to put these efficiency-boosting technologies on their vehicles, and costs go up, people may just hold onto their cars,” says Steve Skerlos, an associate professor at the University of Michigan’s Mechanical Engineering department and co-author of the paper. “The fleet out there could get older, and then we’re offsetting those gains.”
Another trend that may offset this so-called CAFE loophole is the fact that smaller cars have never been so appealing. New models like the Ford Focus, Chevy Cruze and Sonic, Mazda3, and others now offer luxury features that used to be available only in large luxury cars. And buyers are responding. GM has sold about 215,000 Cruzes so far this year. Most likely, carmakers will offer vehicles in every size class and the buyers will choose which suits them. That 54.5-mpg average for 2025 assumes that the truck/car mix will change from the present 50/50 to 38/62, with a lot more folks choosing cars over trucks. As refined and efficient as smaller cars are these days, it’s far too early to tell if that projection will be anywhere close to accurate.
Both Whitefoot and Skerlos are quick to point out that, while they’re exposing one of CAFE’s most troubling unintended consequences, the net result of the new regulations will still be a dramatic reduction in fuel burned and emissions spewed. “That’s the issue I’m struggling with,” Skerlos says. “If automakers go along with CAFE in this structure, there will be pollution that could have been avoided, but it’s certainly a lot better than nothing. In that sense, to me, it’s acceptable.”
The above story is reprinted (with editorial adaptations by the U-M Mechanical Engineering Department) from materials provided by Popular Mechanics. Read the original story at Popular Mechanics’ site.
For additional news, see the UPI article, “Bigger cars find loophole in economy rules.”
