> The power required would be the same as that provided by the bunker fuel engines in common use
And that is a lot of power! Emma Mærsk has an engine output around 80-90MW.
The largest off shore wind turbine today is 26MW with a rotor diameter north of 300m/1000ft(!!). Common (modern) offshore wind turbines today are about 10-15MW with rotor diameters of ~220m/720ft.
I will not conclude it is impossible at this end of the scale, but you need a huge foil area to match such engine output.
> The power required would be the same as that provided by the bunker fuel engines in common use
And that is a lot of power! Emma Mærsk has an engine output around 80-90MW.
The largest off shore wind turbine today is 26MW with a rotor diameter north of 300m/1000ft(!!). Common (modern) offshore wind turbines today are about 10-15MW with rotor diameters of ~220m/720ft.
I will not conclude it is impossible at this end of the scale, but you need a huge foil area to match such engine output.
IIUC, the physics work against us as we scale up in size, because of the square/cube-law https://en.wikipedia.org/wiki/Square%E2%80%93cube_law (weight of the foil/sail + mast is cubed when the area is squared).