The coal market is on life support, and it is natural gas that is absorbing its market while renewables continue to mature. 

Wiki
In 2005 coal provided approximately 50% of electricity in the United States and about 92 percent of coal consumption went to electricity generation. However, in 2016, the EIA calculated that coal would provide only 30% of electricity generation nationwide with natural gas providing 34%, nuclear, 19%, and renewables, 15%.

By January 2016, more than 25% of coal production was in bankruptcy in the United States[8] including the top two producers Peabody Energy and Arch Coal.  By March 2017, the coal industry employed approximately 77,000 miners with 60,000 jobs having been eliminated since 2011. When Arch Coal filed for bankruptcy protection, the price of coal had dropped 50% since 2011 and it was $4.5 billion in debt.

Between vanishing market and debt...the coal industry is done.