Arch Coal, Inc. · St. Louis, MO United States ·(NYSE: ACI)

What powers your power company? Perhaps Arch Coal. About half of the electricity generated in the US comes from coal, and Arch Coal is one of the country's largest coal producers, behind industry leader Peabody Energy. Arch Coal produces about 140 million tons of coal a year from about 20 mines in the western US and Central Appalachia; the company has proved and probable reserves of 2.8 billion tons. Steam coal -- low-ash coal used by electric utilities to produce steam in boilers -- accounts for the vast majority of the company's sales. To store and ship its Appalachian coal, the company operates the Arch Coal Terminal near the Ohio River. To read the full description, subscribe now.