Of the use of coal to build ships

Hello everyone,

I recently asked myself why battleships and cruisers need coal to be built ? At that time the majority of ships used coal and as such wouldn't it be better if this ressource was needed to build them instead of oil ?

I think this could be a good change because it would make coal a much more strategic ressource (a part from building railroads nothing can be done with it.).

Yes you are right, oil is the most important energy ressource.

But this is why I also asked if coal could be used to build BB and LC instead of oil.