Global demand for U.S. coal exports continues to sag, and domestic demand at power plants has been sliding as well.

According to a recent SNL Energy report, for the first time ever, natural gas has passed coal as the top fuel source for electric power generation in the U.S. with 31 percent of electric power generation coming from natural gas and 30 percent, down from 44 percent in 2010, coming from coal.  The transition away from coal has been stunning.