Coal Burning: 200 Million Tons and Counting

This'll give you an idea of how much coal Americans are burning: Peabody Energy, the world's largest private-sector coal company, has a ticker showing its estimated 2007 coal sales. The ticker goes up by seven or eight tons every second.

Peabody says its coal products fuel approximately 10 percent of all U.S. electricity generation and more than 2 percent worldwide. Which means we're burning roughly 70 to 80 tons per second in this country alone. A large power plant operating in peak season may burn as many as 500 train cars' worth of coal in a single day.

Coal is relatively cheap, and we have lots of it. But despite constant references within the industry to "clean coal," nobody has yet come up with a cost-effective way to burn large amounts of coal without releasing heat-trapping carbon dioxide gas into the atmosphere.—Dawn Stover