Outdoor Coal Bunker/ Indoor Coal Bin Questions

I would like to use a coal fired stoker boiler in my basement. My indoor coal storage capacity is enough for one season but living far from the mines and breakers, it makes more economic sense for me to buy a larger load and store it. I could build an outdoor bunker then in the summer or fall I could move my seasonal needs indoors. Is there any problem with this plan that I can't foreseen? Does coal lose it's heating value over time with open storage?

I think you'll be fine with an outside bin, that's were mine is. Had I known for sure that I'd be here the following winter, I would've doubled up on the load I got in June.

Sounds like a good plan. I don't think the coal will lose its heating value. It has been sitting underground for a jillion years. A year on the surface shouldn't hurt it.