My favorite green energy miracle fantasy these days it's wind-powered autonomous ships, cruising cross-wind wherever the weather is best suited, going nowhere as far as they can. With an appropriately sized underwater fan driving a generator which drives a hydrolyzer, and when the hydrogen storage that fills the bulk of its hull is approaching maximum capacity it sets home to the homeport (or wherever prices are favorable for selling the harvest and buying maintenance?). That would solve both mooring and transmission for true offshore wind harvesting, and if someone found a way to build that thing cheap enough for making a profit from the hydrogen, that miracle of market economy which so often causes tragic outcomes would cause more to be built until whatever demand for hydrogen we might create is saturated.
(Buy I'd expect the winning designs to be kite-based, and according to jmoorebeek's dismissals of kites for transport they should do well for this use case of mostly stationary criss-crossing. Hulls could be of the semi-submersible type, for stability, where only a narrow tower for sensors/comms/sails protrudes to the surface, because no cranes would be involved in operation)
Oh, nice! I'm really surprised that they go the flettner way, but I'm sure they did more calculations than me (i.e. > 0).
This entire approach is really just a matter of sufficiently cheap implementation I think. (and perhaps a bit of judicial modernization when it comes to unmanned units on international waters?)
When you can build a unit cheap enough to recoup manufacture and maintenance from the fuel harvested, it would be no less meaningful than crossing the break-even in fusion. I guess unattended hydrolyzation would be the main open todo?
(Buy I'd expect the winning designs to be kite-based, and according to jmoorebeek's dismissals of kites for transport they should do well for this use case of mostly stationary criss-crossing. Hulls could be of the semi-submersible type, for stability, where only a narrow tower for sensors/comms/sails protrudes to the surface, because no cranes would be involved in operation)