Science Magazine Calls Miles Per Gallon An "Illusion"

Richard Chen
by Richard Chen
science magazine calls miles per gallon an illusion

Two Duke University Business School researchers studied the difficulty in perceiving gas saved when comparing vehicles rated by miles per gallon (mpg), versus gallons per 100 miles (gpm). The eggheads argue that the latter more closely reflects real world savings. The article [sub] and accompanying notes illustrate the problem: a nonlinear relationship between mpg and gpm. An example… At 10k miles per year, moving from, say, a Chevrolet Tahoe at 15mpg (6.7gpm) to a Chevy Traverse (that's a Buick Enclave for dummies) getting 20mpg (5.0gpm) nets a savings of 166 gallons. [ED: providing you could get someone to buy the Tahoe.] Moving from a Corolla at 30mpg (3.3gpm) to a Prius at 45mpg (2.2gpm) nets a less impressive savings of 111 gallons. When given the mpg numbers, tested individuals thought that the latter saved more gas than the former. (Our B&B knew this intuitively all along, of course.) Europe at al are already on liters/kilometers, so why not make the switch?

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  • Gsp Gsp on Jun 21, 2008

    the L/100km we use here in Canada is stupid. KM/L would have been better but i still think in MPG and i was born in the 70's.

  • RogerB34 RogerB34 on Jun 21, 2008

    The purpose is to get the Peasants to think in terms of weight of tail pipe carbon per mile as the EU's do. With realization of the evil they are inflicting on the environment, then carbon tax gasoline at the pump. UK has such a proposal pending. A government card would automatically record weight of gasoline to be taxed.

  • John Horner John Horner on Jun 21, 2008

    The researchers got it right, but the US will never change. I still remember that we got 20% of the way along to metric conversion and then said ... nah, forget it. In many ways the US is a very backward place. Certainly our population on average shows poor math and language skills.

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