There is no doubt in my mind that I have a larger than average carbon footprint. Sure, we recycle (but we do not compost.) I keep a very tight control on our heating and air conditioning (but we have more computers and tvs than people.) But my main concern (for so many, many reasons) is that I have a reeeaaallllly long commute. Since I drive a hybrid car, I started wondering how much that offset my 50+ mile commute. As it turns out, there are lots of carbon footprint calculators. Lots. And none of them match.
Using the same basic information, I set out to see if I could get anywhere near the same results from them.
1) CarbonFootprint.com My result: 28.88 tonnes of CO2. They say the US National Average is 20.40. Not surprisingly, factoring in 2 commutes of 40+ miles was the major contributor here.Though, my longer commute in a hybrid car was half what shows for Jay's slightly shorter commute in a moderately efficient crossover vehicle. (As a note, Jay gets all the credit for the hybrid as it was his before I stole it for my long commute.)
What I liked about this site: They asked about lifestyle preferences. Vegetarian? It'll give you credit for that. Only buy organic produce? It factors that too. Also, if you wanted to off-set your carbon footprint, it links to a page that gives you several options, with descriptions of each organization. Their carbon off-set costs ranged from $360 to $700. Oh, and I did like the cute (but sad) graphic.
What I didn't like about this site: The final result is in tonnes, and sadly, it took me a little while to figure out that's the same as tons. My sister also tested this site and thought it was a little cumbersome, so I'd say this one is only for someone who really wants to spend the time to get [what I hope is] a really accurate picture.
2) The Nature Conservancy's Calculator: My result: 75 tons. They say the US National Average is 80.
What I liked about this site: I really liked that you were asked about changes you could have made in the home, such as efficient lights or Energy Star appliances. And that you can see the effects each of those things has on your score as you go.
What I didn't like about this site: Wow! Talk about expensive. They recommend a donation of $1500 to "help protect land, plant trees and measure and verify the amount of carbon that they sequester over the next 70 years." There is some great information about their group along with their recommendation.
3) EPA's Individual and Household Emissions Calculator: My result: 60,550 lbs of CO2 per year. They say 62,250 is the US average for a household of 3. I had to do the math to get to tons to compare with the others (2000 lbs in a ton, FYI). 30.28 tons per year for us, 31.13 as the natural average.
What I liked about this site: There's a section that walks you through positive changes you could make complete with the cost and energy savings from those actions, with labels (no cost, $, $$, and $$$) to show you the cost for each action.
What I didn't like about this site: There were no lifestyle questions, and no place to "get credit" for improvements to your house. No helpful links to places to off-set your carbon footprint either.
4) An Inconvenient Truth > Carbon Calculator: My result 25.05 tons per year. They say the national average is 7.5 per person each year. That puts a household of 3 at an average of 22.5.
What I liked about this site: Quick and easy, this would be a great stop for someone wanting to spend 3 minutes to see where they are in comparison to the national average. Their link for off-setting your carbon footprint was the cheapest one yet - $294. A bargain for easing that guilty conscience!
What I didn't like about this site: Since there was no place to enter two cars, I had to do the calculator twice to get our household footprint. They also don't list any vehicle options after 2006. For me, there wasn't enough to it, but I can see how this would appeal to others.
5) BP Energy Calculator: My result: 24.8 tons per years. They don't list national averages, at least not in an easy to see place.
What I like about this site: It had fun flash animation. The questions are standard, with some lifestyle and household improvement questions.
What I don't like about this site: It's hard to have complete faith in the site when it's a for-profit energy company, but they do seem in-line with the others. No place to off-site your footprint, completely unsurprisingly.
Final thoughts - Most of the sites were somewhere in the same ballpark: from 24.8 to 30.3. Nature Conservancy was drastically different than the others, and their offset costs reflected this! Depending on the source, we're either just over the natural average, or just under. It makes me feel a little better about our ridiculously long commutes - just a little though! Now that I have a pretty good idea where our footprint falls, I can start researching ways to off-set it. I'll share that as I learn more!