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Transportation Science

Why Fuel Efficiency Advances Haven't Translated To Better Gas Mileage 891

greenrainbow tips an article about a research paper from an MIT economist that attempts to explain why technological advances in fuel efficiency haven't led to substantially better gas mileage for the average driver. Quoting: "Thus if Americans today were driving cars of the same size and power that were typical in 1980, the country’s fleet of autos would have jumped from an average of about 23 miles per gallon (mpg) to roughly 37 mpg, well above the current average of around 27 mpg. Instead, Knittel says, 'Most of that technological progress has gone into [compensating for] weight and horsepower.' ... Indeed, Knittel asserts, given consumer preferences in autos, larger changes in fleet-wide gas mileage will occur only when policies change, too. 'It’s the policymakers’ responsibility to create a structure that leads to these technologies being put toward fuel economy,' he says. Among environmental policy analysts, the notion of a surcharge on fuel is widely supported. 'I think 98 percent of economists would say that we need higher gas taxes,' Knittel says."
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Why Fuel Efficiency Advances Haven't Translated To Better Gas Mileage

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  • Statistics (Score:5, Insightful)

    by homer_s ( 799572 ) on Friday January 06, 2012 @07:15PM (#38616056)
    I think 98 percent of economists would say that we need higher gas taxes Knittel says.

    93% of all statistics are made up. 99% of economists know that.
    • Re:Statistics (Score:5, Informative)

      by DanTheStone ( 1212500 ) on Friday January 06, 2012 @07:23PM (#38616164)
      He should ask some economists. If we wanted to optional travel, gas taxes would help. But our whole nation's economy depends on motor vehicle travel to move goods. Raising gas taxes would significantly increase the cost of all goods and possibly bump us toward recession. It happens every time gas prices spike due to factors outside our control. So maybe the number of economists wouldn't be 98% after all.
      • Re:Statistics (Score:5, Insightful)

        by SleazyRidr ( 1563649 ) on Friday January 06, 2012 @07:38PM (#38616374)

        Even then, goods that need to be transported further will increase in price more, leading more people to choose locally produced stuff, benefiting the economy in that way.

      • Re:Statistics (Score:5, Insightful)

        by ConfusedVorlon ( 657247 ) on Saturday January 07, 2012 @07:26AM (#38620566) Homepage

        Not so simple.

        1) Raising fuel taxes a lot certainly influences car choice and average mileage. Look at the average car in the UK vs the average car in the USA.
        The large trucks/suv/etc which are common in the USA are almost unheard of in the UK. Similarly, your idea of a compact economy car (e.g. at a rental company) is our idea of a large sedan. Over the last few years, our fuel costs overall have gone up significantly and there has been a noticeable shift towards smaller more economical cars. I can't find hard stats, but I'll eat my hat if this doesn't flow through to average mpg.

        2) Raising more tax via fuel would allow the government to reduce the tax burden elsewhere - so there isn't _necessarily_ a significant impact on the cost of all goods - just a shift of cost towards goods with high transport costs.

    • Re:Statistics (Score:5, Informative)

      by hedwards ( 940851 ) on Friday January 06, 2012 @07:37PM (#38616364)

      This is a well known phenomenon and it's why you see such incredible fleet efficiency in Seattle compared with most of the rest of the country. Simply put between taxes and oil company gouging we pay more for our gas than they do in most of the rest of the country.

      It's been known since the 19th century: http://en.wikipedia.org/wiki/Jevons_paradox [wikipedia.org]

      Simply put if you don't tax the fuel sufficient to make up for the cost reduction you tend to get more fuel being consumed rather than less. There are limits to it, you're not going to suddenly start commuting 1000mi a day simply because of cheap gas, but it's less likely that you'll work close to home than if the gas was really expensive.

  • by Rifter13 ( 773076 ) on Friday January 06, 2012 @07:15PM (#38616058) Homepage

    The increase in gas prices hasn't drastically changed what vehicles we buy. Many of those that really would rather buy more efficient vehicles can't afford them, and are stuck with older ones, so the economists would just be hurting the poor.

    As consumers shouldn't we choose what vehicle economies we use? Where I live, SUVs are all over. But, it makes more sense. Adverse conditions favor SUVs. An economist, you would think, would say people buy what they want.

    • by Anonymous Coward on Friday January 06, 2012 @07:18PM (#38616096)

      Adverse conditions to not favor top heavy rear wheel only SUVs.

      • Re: (Score:3, Insightful)

        by sneakyimp ( 1161443 )

        Yeah, get a Subaru.

        Mod parent up.

      • by h4rr4r ( 612664 )

        Why is he modded down? He is correct. An AWD subaru or something like it would be a much better choice.

      • I have 2 cars, a ford focus and a nissan xterra. the xterra is much better to drive in the snow. That doesn't mean i put it in 4wd and drive like a bat outta hell. It means i can just sort of plod along and never once has anything in the rockies, the midwest, or the northeast ever come close to stopping me. Compare that to the focus. It's front wheel drive. With all season tires, it's not a bad car for light snow, but it just doesn't have the ground clearance or wheel diameter to handle a significant amount
        • by lorenlal ( 164133 ) on Friday January 06, 2012 @08:11PM (#38616854)

          True enough... A lot of them think they can drive just like there's no snow, and others don't know how to drive in snow anyway.

          I live in one of those "not so friendly" areas. I also drive a car, front-wheel, with a diesel engine sitting right on top of the drive train. I handle snow very well, and better than some trucks and SUVs that I see... That or the drivers don't know how to handle what they've got.

        • by dasunt ( 249686 ) on Friday January 06, 2012 @08:20PM (#38616952)

          I have 2 cars, a ford focus and a nissan xterra. the xterra is much better to drive in the snow. That doesn't mean i put it in 4wd and drive like a bat outta hell. It means i can just sort of plod along and never once has anything in the rockies, the midwest, or the northeast ever come close to stopping me. Compare that to the focus. It's front wheel drive. With all season tires, it's not a bad car for light snow, but it just doesn't have the ground clearance or wheel diameter to handle a significant amount of the stuff.

          I think you'd be surprised with what a great pair of winter tires will do on a little four-cylinder FWD car.

    • by dkleinsc ( 563838 ) on Friday January 06, 2012 @07:23PM (#38616152) Homepage

      Actually, it did have an effect - when gas started to get to about $4 per gallon, there were several studies that determined that people responded by driving less. This makes sense, because driving less is an adjustment that's usually much faster and easier to make than buying a new car.

      However, I for one would be interested to find out what the true cost of a gallon of gasoline is. Not just the price I pay at the pump, but the price I pay in taxes to support the wars where oil is secured, the price I pay in taxes to support the Medicare and Medicaid costs of those harmed by the pollution, the higher prices I pay for anything coming from anywhere near the Gulf of Mexico because the rig exploded, etc. Yes, in theory all those prices should get factored into what I see at the gas pump, but in practice that simply doesn't happen.

      • by Stumbles ( 602007 ) on Friday January 06, 2012 @07:54PM (#38616620)
        That easy, especially if you live in a State like Ohio. On all the gas pumps is a sticker that shows the combined percentages of Federal and State taxes applied to a gallon of gas. Last I looked it was like 49% went to taxes.
        • by dkleinsc ( 563838 ) on Friday January 06, 2012 @08:05PM (#38616778) Homepage

          You misunderstand my point, which was about artificially lowering the price of gasoline based on externalizing costs.

          For instance, if BP is pumping oil out of an oil field in Iraq, right now they are benefiting from the security provided by Xe contractors paid for by tax dollars. If they had to pay for that security, that would cost them, say, $100 million, then the cost of the, say, 2 million barrels of oil they get from that is actually $50 lower than it should be, which translates to a few dollars per gallon of gasoline.

    • by sneakyimp ( 1161443 ) on Friday January 06, 2012 @07:26PM (#38616210)

      SUVs are a complete waste of resources (metal, petroleum, etc.) and enormous polluters. Why use a 3-ton vehicle to drag one fat ass around town? The problem as I see it is that folks are choosing what economy they want which means that self-indulgent rich dicks want land barges that pollute *my* environment and their petro dollars go to such enlightened states as Saudi Arabia, Iran, Venezuela, Iraq, and Nigeria, all of whom seem to hate Western society which means we have to spend still more dollars propping up one petty dictator after another and then knocking them down. If our fuel economy was twice as good, our geopolitical interest in those dodgy areas would probably cost us a lot less money.

      I can appreciate not wanting one's taxes raised. How about we reduce federal income tax and shift the tax burden to a petroleum tax?

    • by tthomas48 ( 180798 ) on Friday January 06, 2012 @07:27PM (#38616230) Homepage

      The poor having SUVs hurts the poor. Government policy has little to nothing to do with it. A gas tax hike and something cash for clunkers would probably do a lot more for the poor than just hoping the price of gas stays low.

      You're basically saying let's not enact a policy because we know there will be pain in the short-term. Lets instead wait and see if it becomes a horrible problem that is nearly impossible to solve. We could have war with Iran, and completely screw diplomatic relations with the Saudis and see gas prices quadruple in a couple months. So really the problem gets back to the fact that people are being irresponsible and buying gas guzzlers. And the market wants to sell them to them because they have huge profit margins. This is exactly like the housing bubble. The government can chose to act now, or they can wait until it blows up in their face and voters are demanding the government give them a credit to buy a new car. A slow rise in the gas tax over a decade could very easily slow the pain and change people's choices in a reasonable manner.

      And SUVs are only great in adverse marketing conditions. Most truck chassis based SUVs I've encountered have trouble getting over a speed bump.

      If consumers should be able to choose what vehicles they want to drive, then they should be able to choose to deal with $7/gallon gas in a car that gets less than 15mpg. I chose to drive a (standard gasoline) car that gets 30mpg because I want to minimize the variability of gas prices on my wallet. I could afford an SUV, but I'm making a choice. As are SUV drivers.

      • Re: (Score:3, Interesting)

        by hedwards ( 940851 )

        If they really worried about the poor, they would tax the hell out of gas and use the proceeds to fund mass transit. The only reason why the poor drive is because there aren't reasonable alternatives. I remember a few years back needing to be downtown early on sundays for work and having absolutely and completely options other than, taxi, private car or bike. The fact that there are times during the week when you have no transit options and that those times of day are more likely to have low income people c

      • by Rifter13 ( 773076 ) on Friday January 06, 2012 @07:44PM (#38616474) Homepage

        And, let me guess, you live in an area that gets little to no snow, and does not have rugged mountains.

        The problem I see with a lot of these types of articles, they are written by (and comments like this made by) people that have not experienced the west. The snow, the mountains, etc. Most people I know, have 4wd vehicles. That is because 2wd, even front wheel drive, are not good at handling really bad roads.

        I've NEVER seen an SUV that had trouble getting over speed-bumps. If you are talking about vehicles cut down, you are not looking at a SUV. You are looking at a toy.

        I can't afford 2 cars. Jumping gas prices would just hurt me. I don't think that FORCING higher gas prices via taxation is a good idea. As it has been shown. With our economy, jumping the gas prices also sends us into a recession.

        • I live in Canada. I've lived in Canada all my life (Alberta and Quebec). I can rock a FWD car out of a snowbank that is up to the wheel wells. If I can't move the car with a shovel, a bit of time, and my own effort, most 4WD vehicles wouldn't have made it out of that situation either.

          I've driven in blinding snowstorms through the crow's nest pass in the Rockies, and I've been stuck on the top of the Coquihalla with the semis putting the chains on their wheels. I made it through there just the same as they did. All I needed was some winter tyres and a modicum of care.

          With traction control systems and some experience, driving in the snow is not a thing that requires 4WD. I know that they're better in the snow and ice, but they're not essential. Even with the car that I have (diesel VW Jetta wagon), which has a very low nose and consequently not much ground clearance, city driving in bad conditions isn't a concern. If it's so bad that I can't move the car, it's too bad to be driving, period.

          If you need an SUV or truck—and there are people that do, obviously—then that's fine. But you almost never need one just for day-to-day things driving in the city.

    • by hawguy ( 1600213 ) on Friday January 06, 2012 @07:53PM (#38616612)

      The increase in gas prices hasn't drastically changed what vehicles we buy. Many of those that really would rather buy more efficient vehicles can't afford them, and are stuck with older ones, so the economists would just be hurting the poor.

      As consumers shouldn't we choose what vehicle economies we use? Where I live, SUVs are all over. But, it makes more sense. Adverse conditions favor SUVs. An economist, you would think, would say people buy what they want.

      Few people really *need* a 4WD SUV or even an AWD car.

      When I lived in the northeast, I commuted entirely with a front wheel drive car. I put on snow tires in the winter, and never got stuck (or in a winter time accident). For 3 winters, I moonlighted as a snow-plow driver for a local business, so part of my commute meant driving in conditions that many people stayed home in (and I regularly saw 4WD vehicles that had run off the road). As long as the roads had less than 8 inches of snow, I was good to go - beyond that I'd need more ground clearance than my car provided. I did resort to chains on a few icy days.

      Smart driving and snow tires are much better than blind trust in an SUV. And unfortunately, many SUV drivers do appear to use that blind trust rather than good driving skills.

      4 wheel drive (or AWD) only helps you move forward, you already have 4 wheel braking, and for most of us, it's the braking that's more important when driving in adverse conditions.

      Now it's possible that you have a need to travel on unmaintained roads to your cabin in the woods, for that I'll grant you that an SUV may be helpful (but not infallible, get a Sno-cat if you *have* to get somewhere in the snow)

  • by Anonymous Coward on Friday January 06, 2012 @07:17PM (#38616084)

    The article links to the peer-reviewed, pay-walled version of the paper.

    http://www.econ.ucdavis.edu/faculty/knittel/papers/steroids_latest.pdf the following is the version author put up on his website

  • So Tax Gas (Score:4, Informative)

    by alexander_686 ( 957440 ) on Friday January 06, 2012 @07:19PM (#38616110)

    If you want to reduce gas consumption (reduce oil imports, reduce green house gasses, etc.,) levy a carbon tax, don't increase gas mileage. Do it directly – not indirectly.

      Forcing me to pay extra to buy a fuel efficient car is going have little impact on the above issues – I don’t drive that many miles (yeah bike, mass transit).

    When the first MPG requirements were put in place, a lot of people switched from big gas guzzling station wagons to big gas guzzling light trucks – the minivan.

    Each year Americans drove more miles until gas hit $4.00 a gallon. Only at that point did they start switching their behavior. Smaller cars and shorter commutes.

  • Are they nuts? (Score:4, Insightful)

    by epyT-R ( 613989 ) on Friday January 06, 2012 @07:21PM (#38616130)

    The reason people hate taxes is because they are commonly used as punitive measures to modify behavior. This is NOT what they should be used for. Thanks to federal and state government not having the discipline to operate within a budget, we pay too much as it is, and coupled with the rise in inflation every time washington prints more money, the people at the bottom are the ones who get burned at both ends, in savings and expenditures. Raising fuel taxes hurts these people even more because they are not able to afford a new car every few years and thus are most likely the ones driving 10+ year old models, nor can they afford to pay even more at the pump than they already are. If money needs diversion to research new technologies then it should come out of the pockets of the oil companies, not consumers. They shoulder enough of the yoke as it is while large corporations are the ones who benefit the most from government economic management.

    • by h4rr4r ( 612664 )

      Federal taxes are at levels lower than almost anytime after WW2. A gasoline tax is not a punishment, it is a method of internalizing costs that are normally externalized. Poor folks normally drive old cars that tend to get better than average mpg. An old Honda civic dx is pretty cheap.

  • by cojsl ( 694820 ) on Friday January 06, 2012 @07:23PM (#38616148) Homepage
    One of the US crash safety standards required by the NHTSA that adds weight and expense to new vehicles is for "unrestrained drivers", despite the fact that under 10% of US drivers go un-belted these days. The punch line is that the IIHS found the NHTSA test not very useful, because un-bented passengers often aren't held in place in front of the intended safety devices.
  • Crash standards (Score:5, Informative)

    by Froobly ( 206960 ) on Friday January 06, 2012 @07:30PM (#38616264)
    While the SUV revolution is more than a little bit to blame for today's lackluster fuel numbers, the article fails to point out collision safety as a factor in the modern design of cars. It's not just the trucks and SUV's that are bringing the average down -- compact cars these days are still way heavier than they used to be, with much worse visibility, largely as a result of increasingly stringent crash standards.

    Cars these days have to be able to protect you in a 60 mph (30 + 30) corner collision, with rollover, even if you aren't wearing a seatbelt. The result is bigger, heavier frames, and thick pillars that prevent you from seeing pedestrians. As a result, cars are heavier, and their engines have to be more powerful to compensate.
  • Subaru Did It (Score:5, Informative)

    by bill_mcgonigle ( 4333 ) * on Friday January 06, 2012 @07:31PM (#38616270) Homepage Journal

    The 2012 Impreza gets 30% better [motortrend.com] gas mileage than the 2011.

    Read the article, but CVT, lighter body, electric steering - 36MPG for an AWD vehicle is nicely impressive.

    Technology, it does good things.

  • electronic junk (Score:5, Insightful)

    by JustNiz ( 692889 ) on Friday January 06, 2012 @07:35PM (#38616330)

    Given all the electronic junk such as ABS, TCS, TPS, multiple airbags, electric seats, motorized windows, mirrors, rear-seat DVD players etc etc that they shovel into cars as standard these days, All the efficiency gained is probably mostly lost in extra weight and power consumption to drive that stuff.

    I for one would welcome the opportunity to buy a simple car without all that junk, except there isn't really the option any more. Apart from the fuel savings, think of the production cost savings the car companies could pass on to the consumer.

  • by NicBenjamin ( 2124018 ) on Friday January 06, 2012 @07:41PM (#38616418)

    Because they're so simple. They would also allow our highway fund to be self-sustaining, which would mean that we could stop subsidizing it with income taxes from people who don't drive. Things like tax credits and CAFE Standards can be gamed.

    In the long-term taxes also have the advantage of getting people used to $6 Gas. Oil production isn't rising. Indian and Chinese guys are finally getting rich enough to drive home for the holidays, which means it's inevitable that gas will go up. Period.

    But since everybody pays the gas tax all the time nobody wants to be responsible for raising it, therefore we get a mess.

  • by lazn ( 202878 ) on Friday January 06, 2012 @07:41PM (#38616420)

    Like say a compact pickup. I'd buy one if I could. (preferably turbo diesel, while I am dreaming) But the Ranger was discontinued, the Colorado is big enough to be a full size pickup of 10 years ago, and the Durango is big enough to be a semi truck, much less the "full sized" trucks. And it's not just the "merican" companies. The last time the Tacoma was mid sized was in 2004, now it's ginormous (same thing with the Frontier).

  • by novalis112 ( 1216168 ) on Friday January 06, 2012 @07:42PM (#38616442)

    I'm not necessarily against taxing gasoline. However, before we start using a gasoline tax as a tool to force people to behave a certain way, maybe we should consider eliminating the billions of dollars of subsidies given to the oil industry so that we can see the *true* price of gasoline?

    (NY Times on oil subsidies: http://www.nytimes.com/2010/07/04/business/04bptax.html [nytimes.com])

    All the posters here keep crying about how "the open market" has failed, but we aren't in an open market, so that is nonsense.

  • by Caerdwyn ( 829058 ) on Friday January 06, 2012 @07:42PM (#38616450) Journal

    What a load of tripe.

    The average weight of cars has been increasing because crash survival standards have been becoming stricter, and that requires that more material be used in the car to protect the passenger compartment. This adds weight and bulk; with bulk (thicker doors, etc.) comes an overall increase in vehicle sizes, which itself adds weight AND frontal area. The frontal area increase comes with an increase in drag. Exotic materials like carbon fiber are still very expensive, so it's still aluminum and steel. And despite what legislators seem to think, you can't pass a law that increases the number of joules of energy in a gram of fuel.

    It's not just American cars (so lose the anti-American screeching please). The average vehicle weight in ALL markets has been increasing. Go look up the dimensions and weights of just about any vehicle model and manufacturer regardless of market or whether the vehicle in question is sold in North America, and see how it's changed over time.

    Safety costs weight and size. Weight and size cost fuel. At a given price point, you can have increased safety XOR increased fuel economy.


  • Safety is the reason (Score:4, Informative)

    by wmelnick ( 411371 ) on Friday January 06, 2012 @08:43PM (#38617186)
    But it is wrong. There are cars from the 1980s that get great gas mileage. The difference is the mandated changes for safety, which has made cars heavier. It takes more steel to make a car crumple the right way. I am not saying this is a bad thing - I am a fan of living through car crashes, but that is where the major mileage decrease happened.
  • Typical /. response (Score:5, Informative)

    by argStyopa ( 232550 ) on Friday January 06, 2012 @09:05PM (#38617386) Journal

    Gas prices are too low...so let's raise taxes? That's our knee-jerk response?

    How about instead of raising taxes which will fall disproportionately on the middle class (the lower classes tend to use public transit), instead let's STOP subsidizing gas and oil exploration, remove massive subsidies, rebates, and all the frosting for our oil-lobby friends?

    Raising taxes on the masses while simultaneously handing $billion$ to oil means that the primary beneficiaries are the oil companies, nobody else.

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