Using a Carbon Footprint Calculator to Live Greener
Using a Carbon Footprint Calculator to Live Greener
If you’re reading this, I presume that you are already well aware that it’s not just big corporations who produce greenhouse gas emissions that lead to climate change. We all contribute to the problem through our transportation choices, buying habits and energy use. Perhaps you’ve wondered exactly how much yearly carbon you as an individual are responsible for adding to the atmosphere. That’s where a carbon footprint calculator comes in.
A carbon footprint is an amount in pounds or tons of greenhouse gases (like carbon dioxide and methane) that we are generating annually by our actions. According to the Nature Conservancy, the average carbon footprint for an individual in the United States is 16 tons per year (which is way more than the global average of 4 tons). In order to get a handle on how well (or badly) you’re doing with your personal greenhouse gas impact, you can use a carbon footprint calculator.
There are a number of free carbon footprint calculators on the internet that will allow you to estimate how much you are personally contributing to carbon emissions every year. I tested out three of them and was surprised by how different the results were. Here is a summary.
Testing Carbon Footprint Calculators
A note on how these calculators work: These calculators can’t give you 100% accurate numbers on your carbon output. But if you want to get the most precise results possible, you’ll need to know how many miles you drive and fly per year, the average/combined mileage that your car gets, and how much you pay for your heating and electric bills. One of them also asks how much you spend on goods and services every month and how many daily calories you eat in various food categories like meat, grains, dairy and so on.
Since my intent was to just get an apples-to-apples comparison on results between the three, I just used some rough estimates, and when in doubt, I overestimated. You can calculate your own impact individually, but if you don’t live alone, it may make more sense to calculate the footprint of the household. I calculated myself and my partner, also making some estimates on his mileage and so on. Two of them gave your total in tons, one gave it in pounds. I did conversions (1 ton = 2,000 lbs) so you can compare.
The Nature Conservancy
The Nature Conservancy’s carbon footprint calculator is the most thorough of the three that I looked at. It asked about your eating and shopping habits in a bit more detail than the other calculators. It also differentiates the impact of your auto based on whether you drive a diesel or a gasoline car. This one is a bit more complicated to fill in because it asks for pretty specific numbers on spending, diet and so on. I definitely did some very rough estimates here, but if you wanted to get really individualized results, this one is probably your best bet.
- My Household Carbon Footprint Estimate: 29 tons/yr (approx 58,000 lbs)
The Environmental Protection Agency
The EPA carbon footprint calculator is pretty simple to use. One of the nice features is that at every step along the way, it offers suggestions for how to bring your carbon totals down, and allows you to measure how much your numbers would be reduced by taking that step. It also gives you some carbon “credits” for recycling. I do wonder about the accuracy of this one, based on the fact that it gave me a considerably lower number than the other two calculators, even though I kept all my usage estimates the same. This one gives you a total in pounds rather than tons, but I did the conversion so you can compare.
- My Household Carbon Footprint Estimate: 27,000 lbs/yr (approx 13.5 tons)
Conservation International
Conservation International’s carbon footprint calculator is a good quick ‘n dirty calculator. Plus you can calculate an individual trip or event. I found this one the easiest to use with simple drop-downs from which you choose various options. The downside is that it’s not as specific, but if you’re looking to get a general idea of your carbon impact, this one is quick and straightforward.
- My Household Carbon Footprint Estimate: 35 tons (approx 70,000 lbs)
Carbon Calculator Conclusions
I’m not sure what to say about how these calculators came up with such different results (13.5 tons per year on the low end, up to 35 tons on the high end). It probably has to do with assumptions that are made in some cases, like about how much natural gas my home uses, versus my own estimates in other cases, which I know are not 100% accurate. I suspect the true number is probably somewhere in the middle. At any rate, it gives me plenty to think about as I plan strategies to get those numbers down. In future articles, I’ll be sharing some steps that I am taking to reduce my climate impact and cut my own carbon footprint.
