There is perhaps no greater act of denial in modern life than sticking a plug into an electric outlet. No thinking person can eat a hamburger without knowing it was once a cow, or drink water from the tap without recognizing, at least dimly, that its journey began in some distant reservoir. Electricity is different. Fully sanitized of any hint of its origins, it pours out of the socket almost like magic.

In his new book, Jeff Goodell breaks the spell with a single number: 20. That's how many pounds of coal each person in the United States consumes, on average, every day to keep the electricity flowing. Despite its outdated image, coal generates half of our electricity, far more than any other source. Demand keeps rising, thanks in part to our appetite for new electronic gadgets and appliances; with nuclear power on hold and natural gas supplies tightening, coal's importance is only going to increase. As Goodell puts it, "our shiny white iPod economy is propped up by dirty black rocks."

Coal has become near-synonymous with electricity because it is cheap and abundant. A pile of coal containing one million B.T.U.'s worth of energy costs $1.70. The equivalent amount of natural gas runs about $9. All electricity looks the same, so why pay more? Even by Goodell's explicitly conservative estimates, America has enough coal to keep its power plants humming for decades to come. And compared with prospecting for oil, finding the black rock is a snap. In Wyoming's Powder River basin the coal seams run 50 to 100 feet thick and lie so close to the surface they can be scoured in open-pit mines.

Unfortunately, coal is also dirty and dangerous. One of the highlights of "Big Coal" is Goodell's outraged account of the catastrophic 2002 flooding of a mine in Quecreek, Pa., run by PBS Coals. His story follows Randy Fogle and Blaine Mayhugh, two of nine workers who survived. Mayhugh, shattered by the experience, left to become a maintenance engineer at a wind farm. Fogle, who came from a long line of miners, returned to the work that had already taken the lives of his grandfather and his wife's grandfather. PBS Coals eventually paid a $14,100 fine for negligence that may have triggered the accident while receiving more than $500,000 from the state for costs associated with the rescue operation.