You can contribute towards the Clan's charcoal resource by working at the firemaking skill plot. As some may think, timber is not required to produce charcoal. Charcoal is, however, needed to skill at the Furnace plot for the production of metal and precious metal bars. By increasing the tier of your firemaking plot, you may find that more kilns are added to your skill plot. All kilns will need to be filled before all of them would be emptied and available for refilling.