Exploring the Cost and Feasibility of Battery-Electric Ships

Wow, this is a really good paper. Supplementary info is really great too- they get into details down to floating charging port stations as part of the infrastructure. Surprising how much demand is from tugboats. I have questions about how you'd safely hook up 5 MW connections, but it's definitely solvable.

Tugboats are a perfect use for battery electric boats! Most tugs work close to a port, they don't need to travel very far, need to be extraordinarily powerful for their size, and they need to change power output rapidly to manoeuvre a ship.

A harbour tug internally is almost entirely engine. Well, two engines, because an engine failure during tug operations is almost always disastrous.