For me, burning coal and wood is kind of like welding at work. There I have three options, Pulse Welding, Spray Arc Welding and Flux Core welding. Some guys use only one kind of welding process no matter what they are doing, even though we are allowed to use any method we want. But because there are pros and cons to each method, there are times when one method is better then the other. For instance, when welding overhead, Flux Core is fast and clean, but when welding flat, you can lay down spools of perfectly formed beads in a day. When mirror welding, you best have Pulse running! The point is, the best welders know what method is best for the situation at hand to get the most production.
So it is with home heating.
I use 60% firewood here, 20% coal and 20% propane.
IF I had to buy a fuel source, I would burn more coal, but in this house coal only excels on those long,cold nights in the dead of winter when the stove just chugs along and pumps out heat. At $354 dollars per ton, it is an expense and a convenience I can live without when I got hundreds of acres of hardwoods just outside my house. Firewood really does not take that long to cut and harvest, and it takes 10 minutes every two weeks to run a brush down the chimney. It really is not that big of a deal. And while I recognize there is no such thing as free firewood even for people like me who have plenty of it growing, it still is cheaper than burning coal. In the dead of winter, it is worth it to buy the coal, but in my home, firewood has its place and I do not see coal eclipsing it anytime soon.
Now if all I burned was propane or oil, coal would be my prominent heat source, just as it would if I was not 38 and struggled to get out into the woods at age 60. I do plan to further reduce my propane consumption by adding (or building my own boiler), but after really crunching the numbers, it will have to be able to burn firewood because it just makes sense to do so.
Just like with welding, I have options available to me, and as much as I love burning coal; for my home, and for much of the heating season, there is a more efficient heat source out there.