A new study in Energy Policy analyzes changes in fuel efficiency of US vehicles between 1923 and 2006. During the Age of the Model T—circa 1923—the fuel efficiency of the overall fleet of all vehicle classes was 14 miles per gallon. In 2006, it was a whopping 17.2 miles per gallon.
Woo-hoo. Proof evolution doesn’t exist.
Researchers Michael Sivak and Omer Tsimhoni at the U of Michigan analyzed the fuel efficiency of the entire US vehicle fleet—cars, motorcycles, trucks, and buses. From 1923 to 1935 fuel efficiency managed about 14 mpg. In 1973 it hit the abyss at 11.9 mpg. By 1991, it straggled upwards to 16.9 mpg. The 1991 efficiency—if you can call it that—was a response to the 1973 OPEC oil embargo and the 1979 Iranian Revolution.
Progress is now stalled. Between 1991 and 2006 the average efficiency improved by only 1.8 percent to 17.2 mpg.
For US fuel consumption to fall by 10 percent, average fuel efficiency across the entire fleet will have to rise to 19.1 mpg. Obama’s May announcement that new cars should average 35.5 mpg by 2016 does nothing to boost the efficiency of the rest of the vehicle fleet.
The study suggests:
- Financial incentives prodding owners to scrap older vehicles in favor of new ones
- Tax breaks encouraging the development and introduction of fuel-saving tech
- Society has much more to gain from improving a car from 15 to 16 mpg than from improving a car from 40 to 41 mpg. The benefits are greater from improving a truck from 4 to 4.5 mpg than from 7 to 7.5 mpg.