The decline in coal stocks deepened Wednesday as investors absorbed President Barack Obama's plan to fight climate change, which aims to cut pollution from coal-fired power plants and increase the use of renewable energy.
Obama will direct the Environmental Protection Agency to develop standards that limit power-plant emissions of carbon dioxide. States would then be able to create rules to comply with the standards.
To reduce emissions, power companies will have to run coal plants less often, install equipment that captures carbon dioxide or shut down plants that become too expensive to operate. The cost to make these changes is likely so great that utilities would instead generate more power with natural gas, nuclear, wind and solar power. That could cut demand for coal, hurting miners.
Low prices for natural gas have already reduced demand for coal from electric utilities in the U.S., battering shares of coal miners.
And renewable energy is growing fast around the world. It will edge out natural gas as the second biggest source of electricity, after coal, by 2016, according to a five-year outlook published Wednesday by the International Energy Agency.
Peabody Energy Corp. and Alpha Natural Resources Inc. fell to multi-year lows. Consol Energy Inc. dropped 3 percent, to $27.10, near a 52-week low of $26.96 struck Tuesday, while Arch Coal Inc.'s shares fell 4.7 percent to $3.62, near its year-long trading low of $3.47 hit on Monday.
Still, some analysts were still skeptical of the White House plan's actual impact. It could face political and legal hurdles that would keep any proposed changes from taking effect soon, said Sterne Agee analysts Michael Dudas and Satyadeep Jain.