This is really nice, and it’s good to be pushing the boundary of what’s possible with electric-only propulsion.

However, whether people like it or not, the most ecological alternative, all things considered, is still heavy fuel oil.

Other fuel sources might look cleaner at first, but after you do the whole analysis (how much cargo is moved, how long the engine lasts, how much energy it takes to create the components, how much is involved in their disposal, ...) it might end up being the opposite.