In This Issue

Do the Math

May 12, 2011
By Rachel Adelson

How does one calculate a carbon footprint?  Does someone slide a metal ruler under your foot like in the shoe store?  Not exactly. 

Environmental experts have formulas for turning, for example, electrical consumption into pounds of carbon dioxide released into the atmosphere. (See right.) 

Thankfully, environmental science has got it down to, well, a science, which spares you from crunching the numbers. Instead, you can use online calculators like the one at

This easy-to-use tool helps you estimate household emissions, explore ways to curb them, and determine potential savings in both dollars and emissions. 

Before you go online, have handy your utility bills and cars’ miles per gallon of gas.  (Need help figuring your fuel efficiency? See 

The EPA estimates that in the United States, a three-person household emits, on average, some 62,250 pounds of carbon dioxide per year. How does yours compare? 

Rachel Adelson writes about technology and the science of behavior from her office near Toronto.

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