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Would that mean emission limits are set lower than technically achievable? Car manufacturers still provide more powerful cars every year. I always wondered, ho

Would that mean emission limits are set lower than technically achievable? Car manufacturers still provide more powerful cars every year. I always wondered, how they can claim their engines emit less while they get faster and faster. Everybody knows that a modern car does not consume so much less fuel than a car of then comparable standard 20 years ago. But lets face it, consumers require more power, less fuel consumption and less emission - in this order. Probably the development of on paper values has been disconnected from the real world for marketing reasons (that is no excuse, its an observation). Before everybody throws stones at Volkswagen only, please measure other cars (again, no excuse). From time to time I rent cars of different brands and at the gas station I see proof that there has been little progress in fuel efficiency. That said, Volkswagen and Audi diesels seem to be the most fuel efficient engines around for the pure power they deliver. The only diesel I know that felt more advanced was a Volvo V60, but mostly because of a geniously constructed gear system and a perfectly rectangular torque (so I had to change gears at 3500 rpm). In Europe (and that means in this case in Germany), car manufacturers invented the fleet consumption and emission. That means, the consumption and emission of a whole class of cars is averaged. This is to trick high powered engines on paper into an acceptable consumption and emission range. The goal is clearly not transparency and openness.

jonknee 11y ago
> Everybody knows that a modern car does not consume so much less fuel than a car of then comparable standard 20 years ago. Actually a modern car does consume a lot less fuel than models from 20 years ago. CAFE standards have had a great effect. http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_04_23.html http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/pub... For a new passenger car the average MPG in 1995 was 28.6 and in 2013 (latest available data for that report) was 36 MPG. That's a 25% increase which when multiplied across millions of vehicles is an enormous amount of fuel.
- mhb 11y ago
  It's a 20.6% decrease in gallons per mile.
  - kazinator 11y ago
    That is misleading. We should calculate percentage improvements against the better value. Fewer gallons per mile is better. For instance, if you cut in half the gallons per mile, it only looks like a 50% decrease. But it's actually a doubling of the mileage: you go twice as far on a tank of gas. The improvement in gallons per mile is 100%. Using something other than mileage: suppose you optimize a program so it takes half the time to run. It's running twice as fast: it is 100% faster. Looking at it as a mere 50% reduction of time can be misleading. If you calculate the speedup using the running time, you have to divide the time difference by the smaller, better running time: 100 x (Tpoor - Timproved) / Timproved. The main problem with the "percent reduction" is that arbitrarily good improvements only approach 100%. If we make a car go a million times longer on a gallon of gas, it's only around a 99.9999 reduction in gallons per mile, which looks only about twice as good as a 50% reduction. :)
    - mhb 11y ago
      Suppose you're going on a 100 mile trip and you want to know how much better off you are if you replace your 50 mpg car with a 100 mpg car. You now only need 1 gallon of gas instead of 2. Even if the car can run without gas, you aren't any better off than a savings of 2 gallons for the trip. You're not > million times better off.
      - kazinator 11y ago
        I'm only not one million times better off because I have other costs to deal with which are completely unrelated to the gas. If the gas were the only resource I have to worry about (whatsoever), then I would in fact be a million times better off.
        mhb 11y ago
        So if the 50 mpg car cost $5,000, you would be willing to pay >$5,000,000,000 for the 100 mpg car?
deleted 11y ago
[deleted]
- grhmc 11y ago
  According to the internet: A 2015 Chevy Impala weighs between 3,650 pounds, and 3,850 pounds. [0] A 1960 Chevy Impala weighs between 3,580 pounds, and 3,960 pounds. [1] Much of a car's body is plastic these days. While features go up, weight generally stays the same. [0] https://www.google.com/webhp?q=weight+of+a+chevrolet+impala+2015 https://www.google.com/webhp?q=weight+of+a+chevrolet+impala+... [1] http://www.oldride.com/library/1960_chevrolet_impala.html http://www.oldride.com/library/1960_chevrolet_impala.html
  - deleted 11y ago
    [deleted]
    - vonmoltke 11y ago
      His research is based on overall sales. Your quote ignores a key point made later in the article: > His research found that light trucks (which include SUVs) represented about 20 percent of passenger vehicles sold in the United States in 1980. That figure had climbed to 51 percent by 2004. In other words, cars are not getting heavier. American car buying patterns are changing. They heavy vehicles American consumers were increasingly buying over that period were the same weight they had always been.

jonknee 11y ago

> Everybody knows that a modern car does not consume so much less fuel than a car of then comparable standard 20 years ago. Actually a modern car does consume a lot less fuel than models from 20 years ago. CAFE standards have had a great effect. http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_04_23.html http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/pub... For a new passenger car the average MPG in 1995 was 28.6 and in 2013 (latest available data for that report) was 36 MPG. That's a 25% increase which when multiplied across millions of vehicles is an enormous amount of fuel.

mhb 11y ago
It's a 20.6% decrease in gallons per mile.
- kazinator 11y ago
  That is misleading. We should calculate percentage improvements against the better value. Fewer gallons per mile is better. For instance, if you cut in half the gallons per mile, it only looks like a 50% decrease. But it's actually a doubling of the mileage: you go twice as far on a tank of gas. The improvement in gallons per mile is 100%. Using something other than mileage: suppose you optimize a program so it takes half the time to run. It's running twice as fast: it is 100% faster. Looking at it as a mere 50% reduction of time can be misleading. If you calculate the speedup using the running time, you have to divide the time difference by the smaller, better running time: 100 x (Tpoor - Timproved) / Timproved. The main problem with the "percent reduction" is that arbitrarily good improvements only approach 100%. If we make a car go a million times longer on a gallon of gas, it's only around a 99.9999 reduction in gallons per mile, which looks only about twice as good as a 50% reduction. :)
  - mhb 11y ago
    Suppose you're going on a 100 mile trip and you want to know how much better off you are if you replace your 50 mpg car with a 100 mpg car. You now only need 1 gallon of gas instead of 2. Even if the car can run without gas, you aren't any better off than a savings of 2 gallons for the trip. You're not > million times better off.
    - kazinator 11y ago
      I'm only not one million times better off because I have other costs to deal with which are completely unrelated to the gas. If the gas were the only resource I have to worry about (whatsoever), then I would in fact be a million times better off.
      - mhb 11y ago
        So if the 50 mpg car cost $5,000, you would be willing to pay >$5,000,000,000 for the 100 mpg car?

deleted 11y ago

[deleted]

grhmc 11y ago
According to the internet: A 2015 Chevy Impala weighs between 3,650 pounds, and 3,850 pounds. [0] A 1960 Chevy Impala weighs between 3,580 pounds, and 3,960 pounds. [1] Much of a car's body is plastic these days. While features go up, weight generally stays the same. [0] https://www.google.com/webhp?q=weight+of+a+chevrolet+impala+2015 https://www.google.com/webhp?q=weight+of+a+chevrolet+impala+... [1] http://www.oldride.com/library/1960_chevrolet_impala.html http://www.oldride.com/library/1960_chevrolet_impala.html
- deleted 11y ago
  [deleted]
  - vonmoltke 11y ago
    His research is based on overall sales. Your quote ignores a key point made later in the article: > His research found that light trucks (which include SUVs) represented about 20 percent of passenger vehicles sold in the United States in 1980. That figure had climbed to 51 percent by 2004. In other words, cars are not getting heavier. American car buying patterns are changing. They heavy vehicles American consumers were increasingly buying over that period were the same weight they had always been.