Earlier this week FirstEnergy, the eighth largest U.S. power producer, announced that it will shut down two coal-fired power plants in Pennsylvania by October of this year. According to the company, new environmental regulations, particularly MATS, were a major reason behind the decision. But Hatfield’s Ferry (HF), the plant which made up over 85 percent of capacity being shuttered, is efficient, can reap economies of scale (at 1.7 GW it is a relatively large plant) and has the most expensive bit of the environmental kit (scrubbers) already installed. In other words, HF is precisely the sort of plant that would have little trouble complying with MATS. So why might FirstEnergy be retiring this plant?