March 5, 2009

Carbon Offsets: Fact or Fiction?

Everyone from motorists to television producers are buying offsets to save the climate. But do they work? David Biello reports

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

The producers of the Fox TV show 24 are going carbon neutral. They're helping to fund a wind farm in India and burning some biodiesel in the production trucks to try to precisely balance the carbon dioxide emitted from all those klieg lights with the amount avoided by generating Indian electricity from the breeze rather than burning coal.

Only problem? The accounting doesn't quite work.

To truly offset CO₂ emissions, a project like a wind farm must be in addition to projects already in the works. If not, such so-called offsets aren't displacing the emissions from fossil fuel burning, they're simply adding more electricity to the overall system. That's the wrong kind of additionality.

This kind of tricky carbon accounting is what led the U.S. House of Representatives to abandon its pledge to go carbon neutral after determining that there is no way to verify that purchased offsets would make a difference. Too bad they already spent $89,000 on them.

Some say offsets are merely a way for the rich to buy their way out of environmental guilt. Whether it's offsets from no-till farming that would have happened anyway from the Chicago Climate Exchange or offsets from hydropower dams in China that would have been built anyway under the terms of the Clean Development Mechanism of the Kyoto Protocol, it's all a bit of a shell game at present.

Keep your eye on total emissions, which rise year after year. And remember: offsets may play a role in any upcoming cap-and-trade scheme to curb CO₂ emissions. We may figure out a way for offsets to be more than a marketing ploy, but the numbers have to add up.

—David Biello

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