MIT study says fuel economy standards are less cost effective than fuel tax

According to a Massachusetts Institute of Technology (MIT) study, government-set fuel economy standards, which have been practiced for many years, are six to 14 times less effective than a fuel tax for reducing gasoline usage.
The objective of fuel economy standards is to reduce gasoline usage overall, but it only reduces the fuel consumption of new cars by making car manufacturers build more efficient vehicles. In contrast, a fuel tax would be an incentive for drivers of all cars — from old to new — to use their fuel more efficiently. A fuel tax is also an incentive for manufacturers to build more efficient cars.
“A tax on gasoline has proven to be a nonstarter for many decades in the U.S., and I think one of the reasons is that it would be very visible to consumers every time they go to fill up their cars,” said Valerie Karplus, the lead author of the study and a researcher with the MIT Joint Program on the Science and Policy of Global Change.
”With a vehicle efficiency standard, your costs won’t increase unless you buy a new car, and even better than that, policymakers will tell you you’re actually saving money.”