A lot of attention gets drawn to cars competing for the highest raw mileage numbers: their car gets 30 MPG, ours gets 32. Theirs gets 48, ours gets 50.
But for real impact, take a car from 15 MPG to 20 MPG. You’ll get the same results as doubling the mileage of a car that already gets 30 MPG. The same results.
Here’s the calculation: take two drivers who both travel 15,000 miles per year. The guy whose car gets 15 MPG consumes 1,000 gallons per year while the one whose car gets 30 MPG consumes 500 gallons per year. Improve the first guy’s mileage to 20 MPG and he’ll save 250 gallons a year. Improve the second guy’s mileage to 60 MPG and he’ll save… 250 gallons a year.
The implication is that modest improvements at the lower MPG end of the fleet have potentially the same overall impact on gasoline consumption as dramatic improvements at the higher MPG end of the fleet.
Of course, the greatest results will come from people walking away from their 15-20 MPG cars and getting into cars that get better than 25 MPG–ideally above 30 MPG. Making this kind of trade usually calls for becoming comfortable with a car that is smaller, lighter, lower to the ground, and has less cargo and passenger capacity. No free lunch, folks.
