Buying Carbon Neutral

GOOGLE the term “carbon neutral” and any number of businesses pop up, offering, for a fee, to offset carbon emissions. It can be hard to tell which businesses are legitimate, and the nonprofit group Clean Air/Cool Planet concluded in a recent study that consumers need to carefully check just what they’re buying.

Its report, “A Consumers’ Guide to Retail Carbon Offset Providers,” is available online at www.cleanair-coolplanet.org. The group notes that it has been involved with one provider of offsets.

The report and independent experts list vital questions that should be asked before buying:

Can the seller show that the offset — for a methane-capturing well or windmill or tree plantation or the like — would not have happened anyway (a characteristic called “additionality” in the industry)?

Is there a way for the provider to show that the difference in emissions benefits because of the extra infusion of cash provided by selling offsets?

There’s what might be called the Brooklyn Bridge effect: Can the business prove that purchased credits are unique and not being sold and resold?

How long does it take for the emissions benefits to accrue, and is there any guarantee of permanence? (These issues have been a particular challenge with the oldest type of offsetting projects — planting trees. Although purveyors of such credits contend that such projects often come with secondary benefits, like reforesting the banks of salmon streams, tree planting is among the most dubious of options. Trees can die or burn, liberating stashed carbon as carbon dioxide once again — which has happened in some such projects.)

The best and most expensive credits, experts say, tend to be those that come through buying and retiring someone’s allowance to pollute, like the credits traded under certain provisions of the Kyoto Protocol, the first climate treaty requiring participating countries to curb emissions.

A big limitation on the availability of such offsets is that the United States, while a signatory, never ratified the Kyoto accord and has no concrete credits for businesses, and consumers, to trade.

The guide to carbon-cutting options listed eight companies out of several dozen that it deemed reasonably reliable. One such company is Atmosfair, a German offsetting company that deals in credits created by building sun-heated rice-cooking kitchens in India and power plants burning methane from wastewater in Thailand.

Another is NativeEnergy, based in Vermont, which invests money in projects like windmills and gas-capturing systems on Indian reservations and small farms.

One company on the report’s list of reasonable performers, the CarbonNeutral Company in Britain, received a much harsher review in “The Carbon Neutral Myth,” a report published recently by the Transnational Institute, an international network of campaigners on globalization and other international issues.

Executives at the carbon-trading company said its differences with that group, which favors strict regulatory approaches to global warming, were mainly philosophical.