With respect to coal you need to determine whether you want to be a supplier or a customer. This will dictate what you build.
As a supplier you are looking at a mine scene - there are a lot of O scale kits to choose from. From the mine ship to a distributor perhaps.
As a customer you have many more options. You can include the distributor up front then follow up with a user. Users can include the power plant cited above. If you are modeling the steam era you can include delivery to a coal tipple in your steam locomotive yard. Also till the 1950's (I think) all cities before the advent of natural gas had coal gas plants. These plants would take in coal to manufacture gas to power gas lamps like street lights and homes. The gas was stored in a telescoping tank called a gas holder. Alan Graziano built a beautiful gas holder that is posted in this forum.
Joe
