Tenshinai wrote:
High quality fuel wood ranges from 1/3 to 1/6 the energy content of petrol and diesel.
And since wood is lighter than petrol, and even using pellets or similar, there´s still a fair amount of air included in it, expect to have a "fuel tank" 5-10 times what would be needed if using petrol or diesel.
But you don't ship wood - you cut it off the side of the road (or pinch it from the farmers wood piles if you have an army with better guns than the farmers).
Wood fired railway engines and steam tractors were widely used anywhere where a forest was to be found - (England and Europe had by this time converted the forests to ships and charcoal so coal firing was more common in developed areas). A wood burning engine can also easily be adapted to burn coal or oil (the reverse is not true as the fire boxes on a dedicated coal burning engine would be too small for wood).