This article is from the In-Depth Report Under the Hood: Building a Better Engine
60-Second Earth

Carbon Dioxide from Cars

U.S. states are beginning to attack another major source of global warming pollution besides power plants: your car. David Biello reports

[Below is the original script. But a few changes may have been made during the recording of this audio podcast.]

Cars in California offer a new kind of sticker shock this year: carbon. In addition to the familiar smog ratings, labels on new Cali cars rank them 1 to 10 based on greenhouse gas emissions.

The best, a perfect 10, will emit less than 200 grams of greenhouse gases per mile. The bad ones more than 520.

Vermont will also begin offering the labels next year. And the 11 states that compose the northeastern region of the U.S. are also attacking the problem at the source: fuel. The states plan to develop new standards for biofuels and other alternatives that will reduce the greenhouse gases emitted when burned in a car, a furnace or a factory. 

These states already cooperate in a cap-and-trade scheme to limit the carbon dioxide emitted by power plants. Other regions, including California and other western states, are copying that plan.

U.S. power plants released roughly 2.4 billion metric tons of carbon dioxide in 2007 generating our electricity. But our vehicles were the second largest source of America’s greenhouse gases. Tailpipes spewed out 1.2 billion metric tons of carbon dioxide from burning gasoline.

The easy-to-interpret labels—10 is great, 1 is bad—aim to change that.  By reminding us to keep emissions in mind next time we buy a car.

—David Biello

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