most all power plants in the u.s.a. use liganite (boiler coal) which has high sulfur, ash, and moisture another name is brown coal. as thomas stated a lot of plants are trying to go to a low sulfer sub-bituminous or bituminous coal which is a lot cleaner. most all blacksmiths coal is a bituminous coal with very low sulfur, ash and moisture. best thing you can do is ask the plant coal buyer where it is from and if they have an analysis of it. or just try some. worst case it will be very dirty, smoke, sparky, stinky coal. matt o