has anyone figured out which is more efficient in terms of labor?
Charcoal, two or three of them outperform deep coal and use only 6 people.
But it’s limit resources
wood is infinite
If you have enough work camps cutting and planting it should be.
4 upgraded work camps 50/50 logging and planting is more than enough to supply 2, four-manned charcoal burners as well as 3 upgraded firewood cutters and two upgraded plank makers, fully staffed. Screw the furniture maker but do have a cooper.
Is it though? Yeah, there’s only 6 people in the charcoal, but you need multiple fully staffed work camps and firewood splitters to support that.
I’d say deep coal is more labor efficient, while charcoal is better/faster if you have the space/labor numbers to use for it.
Charcoal also has the benefit of not being tied to a location potentially half a map away, as you can place your burners/camps/choppers anywhere you want.
the logistics efficiency probably makes up for any labor inefficiency.
I’d actually say logistics is the biggest argument for charcoal other than historicity. (Mineral coal has enough sulfur to make steel too brittle for its main applications, which is why it didn’t really get used in foundries until someone figured out that coked coal solves that problem.) Other than the people in the work camp, everything can be clustered right around the storage yard.
(Although, again with the acceptable breaks from historicity, charcoal was usually made at the logging site, rather than at the destination, because charcoal kilns were single-use constructions.)