2.7GWh / 24h ~= 100MW. That's SMR territory per ship, or a proper nuclear power plant if a few of them charge at the same time from empty to full, assuming they aren't all empty at the same time...

That kind of load is roughly comparable to what a modern rail network consumes. We're talking heavy transport here, of course it consumes power. The London underground consumes something like 1.2twh per year. Peak loads of around 150 mw. It's very comparable.

Harbors are already very large consumers of power. Sure, this adds to that demand but if you think about all the cranes, heavy industry, refineries, freight trains, etc. you can get to a few hundred mw easily. Adding more would definitely need planning. But it's not so dramatic. This just sounds like a good reason to invest in power generation.