Our family of three lives in a major metropolitan city, owns one car and travels by air about 20,000 miles per year on vacation. We're meat eaters and cook on a gas range, but have no pets. So what's our "carbon footprint"—the yearly amount of carbon dioxide we emit into the environment? Anywhere between seven and 23 tons of greenhouse gases generated every year, based on online calculators.
Since the term carbon footprint entered the conversation, consumers have become increasingly aware of their consumption, travel and leisure choices and their impact on the environment.
To address that awareness, a number of companies have found a way to help the environment and ease guilty consciences at the same time. Now, consumers can turn to carbon-offset retailers, which calculate fossil-fuel consumption and neutralize it with earth-friendly initiatives. There are varying ways these credits are put to use, but examples include investing in reforestation, renewable energy and methane-gas capture-and-destruction efforts.
This carbon-offset market, while still somewhat new, doubled in 2008, says Katherine Hamilton, director of Ecosystem Marketplace, a Washington, D.C.-based non-profit that tracks environmental markets. While most of that growth was among corporate buyers, individuals purchased more than one million tons of credits online.
We tested five online carbon-offset retailers that deal with individual consumers, using their carbon calculators to assess our emissions footprint and choosing offsets in different increments. Most sites offered the choice of paying a lump sum to offset our total carbon emissions for a year, as well as partial offsets for travel, utilities or car use. Many also offer "products" to offset anything from the buyer's wedding to their pets.
We had to tutor ourselves in the different standards used to make calculations, and it was difficult to assess the quality of projects each organization funded. As noted, estimates of our personal carbon footprint ranged from seven to 23 tons. The price of offsets was similarly variable, ranging from $2.75 to $14 per ton.
Regulation of the offset market is "if not in its infancy, then in its adolescence," says Michael Gerrard, a Columbia University law professor and director of its Center for Climate Change Law, which means the onus is on the consumer to perform due diligence before buying.
The key to finding reputable offset retailers, we learned, is to look for offsets that are verified by a third-party—the Voluntary Carbon Standard or Climate Action Reserve are two standards used. This verification helps ensure that the initiatives are "additional," meaning the carbon reduction would not have occurred without the project, and are "real," meaning the emissions reductions are properly quantified and audited. All five of our test companies met these requirements.
TerraPass, which evolved from a class at University of Pennsylvania's Wharton School, sells offset products such as a year's worth of carbon offsets for a family of four ($369) or credits for an average-sized car ($71.40, or $35.70 for a hybrid). Terra Pass's online carbon calculator asked for the year and make of our car, and allowed us to compare our car's emissions (1,770 pounds per year) to the national average of 12,000 pounds per year.
After estimating our average yearly air travel and home-energy usage (tabulated in part by zip code), the calculator informed us our footprint was 9½ tons a year.
"The main point of the calculators is education," explains Erin Craig, chief executive of TerraPass, who notes that carbon calculators from various companies must be convenient for consumers to use and make estimates based on broad assumptions. "We're showing people how differences in their choices or behaviors can affect their footprint," she says.
After going through this exercise, we decided to purchase a metric ton of carbon offsets ($13.12) and a two-pack gift box of "climate change chocolate" ($10). Our chocolate arrived two days later, along with a nice box with energy-saving tips printed on it. Every bar of chocolate purchased funds 133 pounds of verified carbon reductions from TerraPass' projects, the equivalent of the average American's daily carbon-dioxide emissions.
Brighter Planet was probably the most educational and social media-savvy of the sites we tried. It also sold the most expensive carbon credits at $14 per metric ton. The site grew out of an environmental-economics class project two years ago at Middlebury College in Vermont and includes innovative features such as its Brighter Planet credit or debit card.
The site's carbon calculator was the most detailed we completed (including food and pets), and we liked that we could refer to our calculations every time we logged on and see our footprint diminish on a bar graph with each purchase we made.
But what about the high price of offsets? Brighter Planet CEO Patti Prairie says that in addition to a panel of experts who review each of Brighter Planet's projects, "we use the most stringent verification we can."
One of the first carbon offset providers, the Carbon Fund is also the only non-profit offset retailer we tried, meaning our purchases are considered donations and are tax deductible. The user-friendly site offered four offset products for different-sized apartments or homes ($49.88 to $200), four choices for different-sized vehicles ($27.21 for a hybrid to $90.70 for an SUV), as well as offsets for individuals and families. We purchased $37.60 worth of offsets for the 20,000 miles of flying we estimated we'll do this year. In exchange, we got a certificate that we printed out at home and a selection of stickers in the mail.
E-Blue Horizons dispenses with offsets for particular parts of one's life. Instead, this no-nonsense site informs users that the average emissions of a two-person household is 30 tons per year and lets them choose offsets in $50 increments, up to $250. Its carbon calculator was similarly streamlined, for example offering us the choice of being specific and filling in our average monthly kilowatt hours of electricity or monthly car mileage, or simply opting for averages based on the sizes of our abode and car. This site is suited to buyers who know how much they want to spend on offsets and aren't interested in the educational aspects of the calculators. The service's reasonable price ($5 per metric ton) is a reflection of the fact, says Anton Finelli, an E-Blue Horizon owner, that the company "actually develops, owns and operates" the landfill capture-and-destruction methane projects that lead to emissions reductions. E-blue also donates half its net proceeds to The Conservation Fund for its reforestation projects, and claims no carbon credits for those donations.
Verus Carbon Neutral offered the lowest-priced offsets we tried: $2.75 per metric ton. Although its primary customers are businesses, Verus includes a calculator that allows individuals to calculate their footprint and purchase offsets. We attempted to fill in the five emissions categories measured, but the calculator wouldn't accept our vehicle and waste information. So we went with a stock estimate and bought 10 tons for $27.50. We then printed out a certificate declaring us "Champion of the Environment."
Andrew Keenan, Verus chief marketing officer, said the company is able to offer low-cost credits partly because offsets are traded on the Chicago Climate Exchange, where they're treated as a commodity rather than a charity. By buying offsets in bulk, Verus keeps over-the-counter prices low.
"Offsets can be a lot like wine," he says. "Some people want to spend $20 for a bottle, when a $2 bottle can be just as good." As for our calculator problems, Mr. Keenan adds, "it's probably a glitch in our calculator. It's one of the most expensive parts of our Web site."