Carbon Dioxide from Cars, Part 2

Transportation is the fastest-growing source of emissions of carbon dioxide. The U.S. aims to change that with stickers. David Biello reports

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Get ready for a new kind of sticker shock in 2012. The U.S. Environmental Protection Agency and Department of Transportation have come up with possible designs for a new fuel economy sticker in a bid to drive consumers to buy more fuel efficient cars.

After all, burning less gas equals less CO2 out of the tailpipe.

One of the big changes is subtle: a switch from the familiar miles per gallon to gallons of fuel burned per 100 miles. That's because mpg doesn't tell you as much as you might think. Boosting mileage from 10 to 11 mpg and 33 to 50 mpg saves the same amount of fuel in the end: one gallon of gasoline every 100 miles.


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One of the designs uses a letter grade to further emphasize best in class performance. Newly available electric cars like the Nissan Leaf get an A+ while heavy trucks and sports cars like the Ford F-150 and Ferraris barely pass with a C and D respectively. In this class, though, nobody gets an F since all cars must meet certain minimum emission standards.

Already, the Obama administration has proposed new rules that would force automakers to make more fuel efficient cars to meet new greenhouse gas emission standards.

Similar stickers already exist in states like California and Vermont, though they use numbers rather than letter grades. For its part, the EPA will be taking your comments on the proposals for the next two months. Already, car companies have begun to argue strenuously against any grades. But there is no doubt that the price of the car will be just one of the pieces of information you can get from its sticker in future.

—David Biello

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