interesting overview of recent car engine technology and politics

Why Not a 40-MPG SUV?
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10 Responses:

  1. it's obvious the writer of this article is the usual pundit who understands neither technology nor finance. here's an example, right off the top:

    It's not that automotive technologies haven't improved; it's that the improvements have been geared toward delivering power, not efficiency. Since 1981 the auto industry has hiked horsepower 84 percent, allowing vehicles to accelerate faster even though they have gotten heavier, according to the U.S. Environmental Protection Agency

    amusing, but dead wrong - an engine that produces more power usually does so through greater volumetric and thermal efficiency. also, acceleration capability does not figure into published MPG ratings because the epa drives all cars on the same test loop following an identical accelleration/decerlation curve. weight and friction are the issue.

    notably, a 405hp corvette Z06 gets about the same fuel economy as miata, and only slightly less than most economy cars.

    the author then goes on to the sort of absurd railings against automakers that are obviously founded in a childish feeling of disempowerment, as in "waa waa, why won't the automakers and the government solve my problems..."

    for example, he cites the CVT as something all automakers should use, and are avoiding because they are either cruel or stupid. CVT's have been around for years on snowmobiles and scooters, but they're a continuous slip device, which means they wear out much faster than gears, and are loud as hell. only very new developments in metallurgy allow them to be practical for moving a four-seater car with modern safety features. similarly, a camless engine (such as on the bmw 745i) requires extremely sophisticated oiling and alloys to allow for non-rhythmic friction loads in multiple directions.

    the final flaw is the author's provincialism - "low fuel efficiency is the fault of american automakers/legislators". for some reason, adoption of these miracle technologies is rare even in countries like japan, with no petrochemical resources to speak of. their camrys burn exactly the same ammount of gas as ours, and the only way they get more fuel efficiency out of their cars is the old-fashioned way - less weight, and better aerodynamics.

    i've got a challenge to the author - think a 40mpg suv is possible? go out and design one!

    • naturalborn says:

      I don't get it - do you disagree that car mileage has been going down, even as technology is improving?

      he cites the CVT as something all automakers should use [...] only very new developments in metallurgy allow them to be practical for moving a four-seater car with modern safety features

      And that distinction makes any practical difference how? Frequently journalists say things which aren't quite technically true but are at least not misleading in the interests of not filling their whole article with technical details and completely confusing readers.

      i've got a challenge to the author - think a 40mpg suv is possible? go out and design one!

      And if you think moore's law will hold up for the next ten years, go out and design a chip which is a thousand times faster than the one on your desktop.

      • I don't get it - do you disagree that car mileage has been going down, even as technology is improving?

        I disagree with the article's "Detroit us holding back on us" attitude. Detroit, as well as Tokyo, and Munich, for that matter, have been working their asses off to give us more fuel efficient cars, that we happen not to be buying, partly because we want more space (parents especially go for large cars as modern children require lots of gadgets) and partially because environmental cleanliness and safety features like crumple zones and airbags are very heavy.

        And that distinction makes any practical difference how? Frequently journalists say things which aren't quite technically true but are at least not misleading in the interests of not filling their whole article with technical details and completely confusing readers.

        It is misleading because the tone of the article suggests that automakers know of all kinds of wonder technologies, but out of spite or stupidity, hold back on them. This is completely untrue. Were the author to at least note the difficulties in implementing the technologies, this would be fair.

        And if you think moore's law will hold up for the next ten years, go out and design a chip which is a thousand times faster than the one on your desktop.

        I don't think Moore's law will hold for ten years for reasons both quantum and thermodynamic. I see performance as coming from parallelism.

        So, I went to work at a supercomputer lab.

        • jwz says:

          It is misleading because the tone of the article suggests that automakers know of all kinds of wonder technologies, but out of spite or stupidity, hold back on them. This is completely untrue. Were the author to at least note the difficulties in implementing the technologies, this would be fair.

          I didn't get that out of the article: what I got was, the automakers know of these cool technologies, but they're in no hurry to finish developing them because fuel efficiency doesn't sell. That's not spite or stupidity, that's market pressure.

          Besides that, I hadn't heard of most of this technology before, and some of it's pretty neat.

          • q says:

            You're right: Auto makers don't think gasoline fuel efficiency will sell -- in ten years. Why? Because they plan on ditching gasoline engines and switching to a fuel-cell-and-reformer system by then. U.S. automakers realize that they've lost the gas-efficiency battle, so they're looking forward to new technologies. In fact, GM recently patiented a membrane-based "low"-temperature fuel cell that could see production within five years.

          • I didn't get that out of the article: what I got was, the automakers know of these cool technologies, but they're in no hurry to finish developing them because fuel efficiency doesn't sell. That's not spite or stupidity, that's market pressure.

            That's an untrue assumption though - fuel efficiency sells extremely well in Japan and Europe, and those two markets combined are slightly larger than America.

            Japan is the world's largest automaker, and the government and corporations there work together.
            Japan has no oil
            Japan is also the nation with the highest early adoption rate for new technologies.

            In spite of these facts, the adoption of "magic fuel-economy technologies" in Japan is rather minimal - sure, Subaru came out with a CVT, which cut fuel consumption by 5-10 percent, but it also blew up every 60k miles and was unsuitable for cars weighing more than 1800lbs - and if you want modern safety features for four, you'll never get under that weight. BMW came out with a camless motor - but the heads for that motor cost as much as a whole Toyota.

            Fuel economy advances slowly because these are simply hard engineering problems to solve - problems that are very meaningful to the majority of auto consumers, who don't live with cheap gas.

            Besides that, I hadn't heard of most of this technology before, and some of it's pretty neat.

  2. papilleau says:

    I'm of the firm conviction that anything you can imagine, you can build, given sufficient motivation. It's like intellectual rock-climbing. I want my hybrid or fuel cell Durango, now. Thanks by the way for the Brin link...

    • Imagine yourself a perpetual motion machine, then.

      Once you get past that pesky laws-of-thermodynamics problem, let me know.

      • papilleau says:

        I'm not interested in why something can't be done. Mere excuses, lack of imagination. Instead tell me how something can be done. I'm no empiricist, and sure as heck not a thermodynamics Nazi. But is the universe forever a closed system, a zero-sum game? I don't think so. Else where did it all come from, and where will it all go? Engineers now do what might have been considered magic just a few generations ago. I am confident that trend will continue.