With all the talk you hear about of offsetting your carbon footprint, you're probably asking yourself, "How do I begin?" Before you know how much you need to offset, you need to figure out how big your footprint is. A quick Internet search will yield dozens of results for carbon calculators. However, some tools are better than others. Here are a few things to look out for when you start calculating your carbon footprint.
The devil is in the details
The more detailed information you can provide, the better you can estimate your carbon footprint. We say "estimate your carbon footprint" because no matter how much information you can put into a calculator, it will always be a best guess of your carbon output. However, in order to get the best guess, you want to find a calculator that has inputs for more than just your household size and how much you drive each year. Some of the better carbon calculators we've tested ask for your average kWh usage, what type of home you live in (multi-family, single-family, big lot, small lot, etc.), average heating costs, whether you use energy-efficient appliances and lighting, how often you eat meat and organic foods, if you recycle and what you recycle, how often you fly, your average gas mileage and how many miles per year you drive.
The law of averages
Even detailed calculators can yield widely varying results based on the same information. Entering the same information in three different calculators, gave us three very different numbers: 18.7, 36 and 45. If you're trying in earnest to calculate your carbon footprint with a goal of offsetting, you may become frustrated by the lack of consistency between carbon calculators. Take a breath, count to 10 and see the previous paragraph. These calculators provide you with estimations. If you're really worried about offsetting accurately, you can err on the side of caution and offset according to the highest calculated result. If you're willing to live with the margin of error, average your results and offset accordingly.
Putting it all in context
Once you have your carbon footprint boiled down to a single number, it's time to think about how you're going to offset that number. Can you drive less, recycle more or make a few home upgrades? Will you buy offsets to balance your greenhouse gas (GHG) emissions? Are you going to offset all of it or just a portion? Does the number describe your carbon footprint in terms of pounds, tons or metric tons? How does your offset plan measure carbon?
Here is a handy reference table to get your units all synced up:
2,000 pounds = 1 ton (a.k.a. 1 short ton) = .9072 metric tons
From here, a few more simple calculations will give you a dollar amount for how much it will cost you to offset your carbon footprint through your chosen program.