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  • William Maley
    William Maley
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    New CAFE Standards = Larger Cars?

    William Maley

    Editor/Reporter - CheersandGears.com

    December 19, 2011

    A new study from the University of Michigan says the proposed CAFE standards could actually make new cars larger, not smaller.

    The study used simulations of 473 different vehicles to figure how automakers could modify vehicle dimensions, implement fuel-saving technology features and trade off performance and fuel economy. Pricing was also taken into account. Their results showed that automakers would increase the size of vehicles to meet CAFE standards instead of adding technologies.

    “For just about all the scenarios, the car got bigger. What you can model in a computer is different from reality, but based on this research we expect it to happen,” said Steven Skerlos, an associate professor in the U-M Department of Mechanical Engineering.

    But why are vehicles growing? Well the study points out in 2007, the CAFE standards were revised. One of those changes was a new formula that measures a vehicle’s “footprint,” calculated by multiplying wheelbase by track width. That means larger vehicles have a smaller fuel economy target, giving automakers a loophole.

    “It’s cheaper to make large vehicles, and meeting fuel-economy standards costs [manufacturers] money in implementing and looking at what consumers will purchase,” said Katie Whitefoot, a researcher involved with the study.

    The study calls on the US government to revise its formula.

    Source: Automotive News (Subscription Required)

    Press Release & Study Result is on Page 2

    CAFE standards create profit incentive for larger vehicles

    Published on Dec 07, 2011

    Written by Nicole Casal Moore

    ANN ARBOR, Mich.-The current Corporate Average Fuel Economy standards create a financial incentive for auto companies to make bigger vehicles that are allowed to meet lower targets, according to a new University of Michigan study.

    Over their lifetimes, these larger vehicles would generate between three and ten 1,000-megawatt coal-fired power plants' worth of excess carbon emissions. A 1,000-megawatt plant could provide power for more than half a million people.

    "This study illustrates that there may be a substantial financial incentive to produce larger vehicles, and that it can undermine the goals of the policy," said Kate Whitefoot, who conducted the research as a U-M design science doctoral student and is now a senior program officer at the National Academy of Engineering.

    "The results show that the policy can be adjusted to reduce these unintended incentives by making it harder to lower the fuel economy targets by producing larger vehicles."

    The study is published online in Energy Policy.

    The loophole is the formula for setting mile-per-gallon targets. The standards, which actually depend on the sizes of vehicles automakers produce, are expected to require that firms boost average fuel economy to 35.5 mpg by 2016 and 54.5 mpg by 2025. Those oft-cited numbers are averages. In reality, each car company must meet a different standard each year determined by the literal "footprints" of the vehicles it makes. A vehicle's footprint is its track width times its wheelbase.

    According to the study, the sales-weighted average vehicle size in 2014 could increase by 1 to 16 square feet, undermining fuel economy improvements between 1 and 4 mpg. That means the industry as a whole would not achieve that year's fuel economy goal.

    "We know it's a broad range, but we looked at a large range of possible consumer preferences for vehicle attributes and the answer is probably somewhere in the middle," said Steven Skerlos, an associate professor in the U-M Department of Mechanical Engineering.

    "Will cars get bigger? Very possibly. Will that lead to more pollution? Yes. And there wasn't an emphasis in the rulemaking process that this could happen."

    The impetus for the footprint-based formula back in 2006 was to prevent an influx of smaller vehicles, though not necessarily to do the opposite. Critics worried that the previous one-size-fits-all standard unfairly and perhaps dangerously rewarded production of slimmer, lighter vehicles that could put the domestic industry at a disadvantage and drivers at greater risk. The researchers believe the correction overshot its target.

    They found that light trucks would grow even more than cars, which could yet lead to traffic safety concerns. They call on the National Highway Traffic Safety Administration to revise the formula.

    This study was more than just an economic analysis. Whitefoot built a first-of-its-kind model that considered supply and demand but also incorporated engineering tradeoffs that carmakers consider as well as a wide range of possible consumer preferences.

    They conducted simulations with 473 different vehicles. In the simulations, auto firms could adjust the size of their vehicles, add fuel-saving technologies, balance acceleration performance with fuel economy, and adjust vehicle prices. The result, Skerlos says, is an exciting new framework where economists, environmentalists, engineers and policymakers can work together.

    "Sustainability is about tradeoffs," Skerlos said. "On the one hand, there's a concern about vehicle size largely driven by safety and the effect on domestic automakers. The adjustment to the CAFE standard tries to achieve high fuel economy while not compromising vehicle size, and the idea here is these things intersect and you have an equivalent of three to 10 coal-fired power plants hidden in that tradeoff."

    The research is funded by the Michigan Memorial Phoenix Energy Institute and the National Science Foundation. The paper is titled "Design Incentives to Increase Vehicle Size Created from the U.S. Footprint-Based Fuel Economy Standards."

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    Lets not hold our breath, this study screams of EVIL AUTOS and POLLUTION.

    Chris Dones post shows that his poor friend in a depressed state tried to pollute himself out of this world and couldn't because it didn't pollute enough.

    Chris not trying to be crude just using that fact as it was in current memory and you are a true friend of his I hope I have that kind of friend if needed.

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    Wanna know a secret? This whole CAFE thing and the EPA's fuel economy ratings really don't amount to a lot. That's why I don't get up in arms anymore about these laws. You can choose what you want to think, but it's two parts substance and three parts vaporware.

    In fact, the EPA performs few mpg tests of their own and simply takes the automaker's word for it instead. Don't believe me? Well, let's visit the EPA's own webpage and you can see the proof for yourself:

    EPA estimates are based on laboratory tests conducted by manufacturers according to federal regulations. EPA re-tests about 10% of vehicle models to confirm manufacturer's results.

    Yes, automakers have to use the complex mathematical formulas given to them by the EPA to calculate what mpg their cars are capable of, but no, the EPA doesn't employ a huge staff people to test the MPG of every car ever built. Actually, out of the seventeen-thousand people the EPA employs only a whopping eighteen of them work in the offices of their automotive department in Ann Arbor, Michigan. (I bet a lot of you here didn't know that the staff was that small.) It's obvious that there's no way a staff that small can effectively test all of the new or improved cars introduced in a given year, hence that's why they only retest 10 percent of cars (and those retests are usually random or if a car claims to be best in class in fuel economy or if a new model has new technology developed specifically towards higher mpg figures).

    Since the NHTSA enforces and regulates CAFE based on the EPA's scores, which are in turn mostly based on the data submitted to them by the automakers themselves, well ... I hope you can see the loophole that's been in these laws since the day they first came about. The government can raise CAFE to 73 mpg tomorrow and the automakers would still be very accepting of it. They would also have a way to still offer cars like the Corvette ZR1, supercharged V8 and all.

    To give a more specific example of what I'm talking about, a lot of naturally-aspirated cars have an "eco" mode that puts a car in a "low-power" state from doing something as simple as changing the throttle and transmission management through the PCM automatically during certain conditions (I should note that no two "eco" modes really work the same, but this is how in a nutshell the system works in my Dodge Challenger and similarly in a number of other cars) . An automaker can do a lot of their mpg tests in this mode alone, plug all of the data into the EPA's mathematical formulas, and -- presto! -- you can boost your mpg scores from okay to good and from good to great.

    That loophole I just described as well as the loophole discussed in the article above aren't the only ones. Of course I know you all know that GM selling the Spark here boosts the CAFE score of Chevy's model range. See, though, that's the thing: no one really has to buy it in order for Chevy's CAFE scores to go higher. Sure, there are people in the United States who have bought so much into all of this they'll buy a Spark just because they think it's so amazing on gas, but it doesn't matter if it's one guy who bought one or a thousand. (It was also designed primarily for markets that favor small cars meaning that, if it flopped here, it would still make GM money.) It also doesn't mean GM's entire portfolio of cars are going to be Spark-sized, front-wheel drive, three-cylinder micro-cars, either.

    Let's also not forget that the EPA's fuel economy guidelines are not regularly updated and still assume a car is burning 100 percent gasoline (most gasoline is ten-percent ethanol now). They also don't take into account how people actually drive cars.

    Don't get me wrong, though. We've seen more efficient automotive powertrain technology come about since EPA started all of this and the NHTSA and CAFE came along to enforce it, but the reason that we're not seeing the resurrection of a rear-wheel drive, V8-powered Chevrolet Impala built to 1968 dimensions isn't because of CAFE. It's really because GM simply doesn't want to build it for whatever reason they can think of.

    If you want to read more about what the EPA does, read this Car and Driver article from 2009 and click around on the EPA's site from the link I provided above. By the way, I sure as hell wished that someone posted that C&D article here when everyone was bitching about the then proposed increases in CAFE. I don't think the increases in CAFE are going to bring the radical changes we originally thought.

    tldr; CAFE and the EPA's mpg laws beg to be bent over and slammed right in their backsides. Go back to bed, this isn't the end of the automotive world like we thought it was going to be.

    Note: Sorry if this post lacks cohesion in anyway. Raise questions and I'll try to hopefully clarify them. Also, if I'm wrong, show me where and how and I'll gladly admit that I am.

    Edited by black-knight

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