EarthTalk: Carbon Offsets

Dear EarthTalk: My global warming guilt is starting to catch up with me, and I’ve heard that I can buy “carbon offsets” to help make things right. How do they work? — Miranda Snavely, Milton, WA

Carbon offsets are monies that consumers and businesses pay voluntarily to compensate for the greenhouse gas emissions they generate directly by driving, flying, running the air conditioning and otherwise using non-renewable energy. Companies and nonprofit groups that sell offsets use the dollars generated to fund alternative energy and other projects that will ultimately eliminate greenhouse gas emissions (such as wind farms that can replace coal-fired power plants in generating electricity).

“Carbon offsetting is one of many economic actions you can take to address climate change, and it is a powerful one,” says the nonprofit Co-op America, “Many promising projects that would help to reduce greenhouse gas emissions lack the capital they need to get built; by directing your offset dollars to these projects, you can help finance new wind farms, solar arrays, and more.”

Dozens of carbon-offset vendors have sprung up in recent years. Consumers interested in buying offsets should do their homework, as some firms have better reputations than others. Co-op America recommends offsets that support specific projects that wouldn’t have happened otherwise and that have measurable near-term goals. Legitimate offset providers should also be able to back up all claims and show a clear money trail to the projects being funded. Co-op America urges consumers to avoid tree-planting programs, which are hard to quantify, and “climate exchange allowances” (also known as “pollution trading” or “emissions trading”), which many consider to be veiled ways of letting companies buy the right to pollute.

Co-op America lauds the Climate Trust (non-profit, funds wind farms in Oregon), TerraPass (for-profit, funds methane gas capture from landfills and farms), Native Energy (for-profit, funds new wind farms and solar arrays) and Sustainable Travel International’s MyClimate (non-profit, funds clean energy in developing countries) as some of the leading offset providers with reputable business models.

Those looking to dig deeper into the ways different offset providers operate should check out Clean Air-Cool Planet’s Consumer's Guide to Carbon Offsets. The free 44-page PDF download assesses the strengths and weaknesses of some two-dozen carbon offset programs. The guide gives highest marks to Climate Trust, Native Energy and MyClimate, although other providers are also praised for specific programs. Another good free online resource comparing various offset programs on one page/chart is on the Carbon Offsets Survey page on the EcoBusinessLinks Environmental Directory.

Consumers should understand that offsets may be convenient, but are essentially only icing on the cake of an otherwise diligent effort to reduce emissions by using energy less and more efficiently. “All the offsets in the world won’t help us,” warns Clean Air-Cool Planet, “if we in the U.S. don’t make big reductions in our overall greenhouse gas emissions and effect a transition away from wasteful use of fossil fuels.”

CONTACTS: Co-op America,; Climate Trust,; TerraPass,; NativeEnergy,; Sustainable Travel International,; Clean Air-Cool Planet,; EcoBusinessLinks,

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