GRAPHIC: How Offsets Work

In November, the U.S. House of Representatives paid $89,000 to buy so-called carbon offsets through the Chicago Climate Exchange. These offsets were supposed to signify that the greenhouse gas emissions of all House office buildings, plus half of the U.S. Capitol, had been balanced out by projects that cut back on an equal amount of emissions. Here's how offsets work:

GRAPHIC: How Offsets Work

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