Paying off our global warming sins

Buying credits to offset our driving and flying is helping to reduce greenhouse gases. But is the "carbon-neutral" movement really enough?

By Katharine Mieszkowski

Read more: Politics, News, Katharine Mieszkowski

May 26, 2006 | Robert Day, 33, a venture capitalist, walks to his office in downtown San Francisco every day. But when he has meetings down south in Silicon Valley, he drives the family's 2001 Subaru Forester, which gets around 23 miles per gallon. Between his meetings, his wife's meetings, trips to the grocery store, and the occasional getaway to Napa or Carmel, this one-car family drives their Subaru about 8,000 miles per year, 4,000 fewer than the national average.

As a venture capitalist for Expansion Capital Partners, a firm that invests in clean technologies, Day's all too aware that his purring engine makes an incremental contribution to global warming. Burning one gallon of gas emits 20 pounds of carbon dioxide into the atmosphere, and in one year, the family Subaru gives off about 6,400 pounds of the greenhouse gas.

But a decal on the back window of Day's Subaru attests that he's done something about it. He's paid $39.95 to a Silicon Valley company called TerraPass to "offset" the CO2 emissions from his car. His money is going to help fund wind farms and reduce the methane leaking out of dairy farms and landfills. By paying to boost alternative energy and cut pollution, Day is neutralizing the greenhouse gases coming out of his own car. He can't put the C02 genie back in the bottle. But he can help jump-start a new way to arrest global warming. Buying carbon offsets is a small gesture, Day says, "but it's a lot better than standing still. It's certainly better to do this than to do nothing."

In the past few years, more than a dozen carbon-neutral companies have popped up to sell the promise that you can mitigate your contribution to global warming, whether your contribution comes from commuting to work, catching a flight for a summer vacation, or just keeping the air conditioning running during those ever hotter summer months. One U.K. company is even promoting the idea of offsetting your baby's disposable diapers. TerraPass's competition includes Carbonfund, NativeEnergy, Certified Clean Car, DriveNeutral and Atmosclear Climate Club.

The new wave of carbon-neutral groups appeal not only to green V.C.s. Last December, Whole Foods announced it offset all of the electricity used in its operations, a claim sure to appeal to the grocer's eco-minded customers. The National Football League has offset the carbon created by the 2005 Super Bowl, while the Winter Olympic Games and a Dave Matthews Band tour have taken steps to go carbon neutral. At the end of Al Gore's global-warming documentary, "An Inconvenient Truth," a NativeEnergy logo on the screen trumpets that all the CO2 emitted by the shooting and editing of the film has been offset. In other words, the global warming caused by the making of a film about the horrors of global warming has been neutralized.

But is going carbon neutral the right path to reducing greenhouse gases? The early reviews by energy experts are mixed. On the positive side, buying offsets goes beyond fretful hand-wringing about government inaction and fist-shaking at polluting industry. Calculating personal greenhouse gas emissions makes people more aware of the ways their own daily activities contribute to the problem. Buying an offset allows them to take an immediate, concrete step, something more than writing a check to an environmental group or sending an e-mail to a congressman.

On the negative side, the best way to fight emissions is to prevent them in the first place, not offset them after they've occurred. Some critics worry that offsetting will encourage guilt-free consumption and shift the focus from conservation. Plus, the number of people willing to pay to offset their carbon footprint is so far small -- the carbon-neutral groups together have customers in the low tens of thousands. The groups themselves, some of which operate as for-profits others as nonprofits, vary in quality and effectiveness, causing observers to warn, "Buyer beware." Other critics say the carbon-neutral movement is a poor substitute for the powerful hand of government.

In any event, understanding the pros and cons of the carbon-neutral groups requires a brief lesson in carbon trading.

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