I always thought the US traditional measure of fuel economy in miles per gallon was a bit misleading once you get to the higher MPG range. For example, an improvement from 17 mpg to 18 mpg is in fact much greater than an improvement from 27 mpg to 28 mpg.
Anyway, the concept is nothing new in ROW, but it seems to be finally picking up steam in the US... The new (2013) EPA window sticker already includes fuel economy expressed in gallons per 100 miles (gp100), albeit in small print for now.
http://www.popularmechanics.com/cars/news/4324986
http://www.edmunds.com/car-reviews/features/mpg-is-stupid.html
Quote:
But why, exactly, should consumers care?
Quick, which is better: Replacing an 18-mpg car with a 28-mpg one, or going from a 34-mpg car to one that returns 50 mpg? Researchers at Duke University say that drivers find it easier to select the right answer when efficiency is expressed as gallons per 100 miles (g/100m). So 18 mpg (or 5.5 g/100m) versus 28 mpg (3.6 g/100m)--an increase of 10 mpg--represents a 52 percent reduction in consumption. If you trade in a car rated at 34 mpg for one rated at 50 mpg, its a 16-mpg improvement, so we ought to see those gas card bills plummeting, right? Actually, after a minute's worth of math, you'll get 2.9g/100m in the 34-mpg car and 2g/100m in the 50-mpg car--only half as big a gain as the original scenario.
The gallons-per-mile system makes it easier to see that our efforts to reduce petroleum consumption and carbon emissions should focus on removing from the fleet the vehicles that have the poorest economy, even if we replace them with ones that only return moderately good economy. Spending five or 10 thousand dollars to put a hybrid or diesel powerplant into a Honda Civic will save fuel. For example, the annual fuel cost of a 21-mpg Taurus is $1742, while that of a 28-mpg Focus is $1307--a 7-mpg improvement, netting a reduction in annual fuel costs of $435.
Now consider replacing a 29-mpg Honda Civic with a 42-mpg Civic Hybrid. One might think a whopping 13-mpg bump in economy would save almost twice as much money compared to moving from the Taurus to the Focus. But let's do the actual math: $1263 annual fuel cost for the Civic minus $871 for the Civic Hybrid equals, umm, $392. Nothing to sneeze at, but shouldn't there be a bigger difference?
Anyway, the concept is nothing new in ROW, but it seems to be finally picking up steam in the US... The new (2013) EPA window sticker already includes fuel economy expressed in gallons per 100 miles (gp100), albeit in small print for now.
http://www.popularmechanics.com/cars/news/4324986
http://www.edmunds.com/car-reviews/features/mpg-is-stupid.html
Quote:
But why, exactly, should consumers care?
Quick, which is better: Replacing an 18-mpg car with a 28-mpg one, or going from a 34-mpg car to one that returns 50 mpg? Researchers at Duke University say that drivers find it easier to select the right answer when efficiency is expressed as gallons per 100 miles (g/100m). So 18 mpg (or 5.5 g/100m) versus 28 mpg (3.6 g/100m)--an increase of 10 mpg--represents a 52 percent reduction in consumption. If you trade in a car rated at 34 mpg for one rated at 50 mpg, its a 16-mpg improvement, so we ought to see those gas card bills plummeting, right? Actually, after a minute's worth of math, you'll get 2.9g/100m in the 34-mpg car and 2g/100m in the 50-mpg car--only half as big a gain as the original scenario.
The gallons-per-mile system makes it easier to see that our efforts to reduce petroleum consumption and carbon emissions should focus on removing from the fleet the vehicles that have the poorest economy, even if we replace them with ones that only return moderately good economy. Spending five or 10 thousand dollars to put a hybrid or diesel powerplant into a Honda Civic will save fuel. For example, the annual fuel cost of a 21-mpg Taurus is $1742, while that of a 28-mpg Focus is $1307--a 7-mpg improvement, netting a reduction in annual fuel costs of $435.
Now consider replacing a 29-mpg Honda Civic with a 42-mpg Civic Hybrid. One might think a whopping 13-mpg bump in economy would save almost twice as much money compared to moving from the Taurus to the Focus. But let's do the actual math: $1263 annual fuel cost for the Civic minus $871 for the Civic Hybrid equals, umm, $392. Nothing to sneeze at, but shouldn't there be a bigger difference?
