Cargo Ship Fuel Modules

Modularize the fueling of the Cargo Ship by making the fueling a separate module building built onto the dock in line with the 2-8 cargo modules. This will allow extensions and changes to the operation of cargo ships, such as coal, nuclear, or other power in addition to the default diesel.

This sounds like a cool idea but it sounds like it'd be a bit hard to work in. I could imagine some kind of system whereby you upgrade your boats to utilize uranium rods and thus be nuclear powered boats. That sounds reasonable for sure...but I think to make it fit inside the game it would have to be a tech tree discovery. Like "nuclear powered engines IV" or something. I mean it makes sense but it sounds like a pretty big change to the game.

Of course different fuel modules could be unlocked by different technologies, just like different cargo modules are.
That's half the point if making it modular with an extra building connected to the dock, so they can be separate technologies and choices.