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EPA Proposes Grading System For Car Fuel Economy
suraj.sun writes with this snippet from CNET:
"The EPA and Department of Transportation on Monday proposed a fuel economy label overhaul to reflect how electric and alternative fuel vehicles stack up against gasoline passenger vehicles. ... The changed label, mandated by the 2007 energy law, includes the same information on city and highway miles per gallon and estimated driving costs based on 15,000 miles a year now available. But the new labels add more comparative information, rating cars on mileage, greenhouse gas contribution, and other air pollutants from tailpipe emissions. That means that consumers can look at a label to see how one vehicle compares to all available vehicles, rather than only cars in a specific class. One label proposes grades, ranging from an A-plus to a D. There are no failing grades, since vehicles need to comply with the Clean Air Act."
Most people argue GPM is better for exactly those reasons - it's easier to compare. For example, you have two cars - one that gets 10 mpg and one that gets 33 mpg. You can replace the 10 mpg with one that gets 11 mpg, or replace the 33 mpg car with one that gets 45 mpg. Quick, which saves more gas?:
A) replace the 10 mpg with 11 mpg
B) replace the 33 mpg with 45 mpg
The answer is A. The first changes from 10 gallons per 100 miles to 9 gallons per 100 miles - 1 gallon saved every hundred miles. Option B changes from 3 gallons per 100 miles to 2.2 gallons per 100 miles - less than a gallon saved (per 100 miles). It's completely non-intuitive if you use the backwards "mpg" measurement.
If we just used consumption instead of MPG, we wouldn't have this problem.
The sticker says "over five years, this vehicle saves $6,900 compared to average". The small print says that's based on 15000 miles/year, and an average of 20-23 mi/gal (21.5mi/gal = 4.65 gal/100mi).
Presumably, your Ford Ranger would have had a sticker like "over five years, this vehicle costs $5,200 more than average" (based on your 14mi/gal (7.14gal/100mi) figure, and $2.78/gal). Would that have influenced your decision? You can rent something that hauls heavy loads many times for $5,200, for example. (And presumably insurance, parts etc cost more on the bigger and more powerful car).
(FWIW, with fuel costs here the $5,200 would become $12,306. You could buy a small car with the saving... and since that one uses 47mi/gal (2.12gal/100mi) you'd save $5300 (or $12500 here) compared to average [I know US gallons are different to the Imperial gallons given on that page, I converted them for you.]).