I've also thought this. There are loads of offshore wind farms in the North Sea and I bet the cost per kWh at the offshore substation is a fraction of the cost compared to the same electricity once stepped up for transmission through the undersea cables to the shore, possibly curtailed due to grid congestion and then transmitted still further to the urban load centers.

If only there was a reliable, mature process to turn air\seawater plus energy at the windfarm into a synthetic fuel (ammonia or methanol maybe?) that could be then stored and used to refuel green shipping that burned no bunker fuel or diesel?