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.

Here is a LinkedIn post from my friends in Plug with a video! It's for connecting to a cruise ship, which are often around 5MW https://www.linkedin.com/posts/plugport_some-great-insight-i...

Electric ferries have already proved out high-power dockside charging, though I'm unsure whether that's primarily marine or freshwater in practice.

https://www.stemmann.com/en/products/charging_systems/ferryc...

This company has designs that go up to 23MW @ 15kV, though I'm unsure what their largest actual installation is.

The Maid of the Mist boats at Niagara Falls have been fully electric since 2023: https://www.maidofthemist.com/maid-of-the-mist-sets-the-stan... They don't talk too much about battery capacity or charging but I'm sure the information is out there.

Here's more about electric tugboats: https://www.youtube.com/watch?v=mu9XZIpOTcw

They can have super high torque. Quiet motors allow them to operate where diesel wouldn't be allowed due noise pollution.

There are IEC 60309 industrial power connectors that can handle 8MW (1000V, 800A).

There are also power connectors for cruise ships while they are in dock that handle lots of power. It looks like they use IEC 80005 for shore power. It looks like it is AC only but probably could be made to use DC.