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 by volume, behind industry leader Peabody Energy. Arch Coal controls a 2.5 billion ton reserve base of metallurgical and thermal coals. It sold about 128 million tons of coal in 2015 from 16 active mining complexes in every major coal supply basin in the US. It produces thermal (steam) coal used by electric utilities to produce steam in boilers and metallurgical coal used to make steel products. In 2016 the company filed for (and emerged from) Chapter 11 bankruptcy protection in a bid to cut $4.5 billion in debt.