By Peg Fong

MIT professor of mechanical engineering Timothy Gutowski recently had his students compare the energy consumption of people in different socio-economic classes -- from a homeless person to a senator. In total, 18 different lifestyles were chosen, ranging from vegetarian students to professional golfers to a five-year-old.
What the MIT researchers found was that even in the U.S., the people with the lowest energy usage -- a homeless person, a five-year-old, and a Buddhist monk -- all have a carbon footprint twice as large as the average global citizen. This is because the services provided for every American, including infrastructure and public services, guarantee a set baseline that no American can drop below.
The carbon footprints of the low energy consumers were about one-third of the American average. Americans are big-foots when it comes to their carbon footprints. The world average is four tons; Americans typically consume 20 tons.
Bill Gates, specifically chosen for the study, has a carbon footprint about 10,000 times the average. Of course, he also has produced a great deal of wealth and growth for the world. In general, the researchers found that as income rises, so do emissions.
A homeless person, who ate at soup kitchens and slept in shelters, had an average carbon footprint of 8.5 tonnes, still twice as much as the world average. Even monks, who lived half the year in the forest, had carbon footprints of 10.5 tonnes.
But the big question of how to lower carbon footprints is tough to answer. The study found that voluntary reductions is likely unobtainable for the average American. Considerably more can be done by the wealthy, but the best way to lower footprints is to tax carbon use which, Professor Gutowski says, is a hard pill to swallow, especially for politicians.
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