Regarding grid connection: It may be that an important issue is...

Regarding grid connection: It may be that an important issue is the overall output from the "farm" - a single buoy might produce power unevenly depending on whether the buoy is rising, falling, or not moving (at the peak or trough of each wave). Power companies would not like this. Three buoys should be able to even this out somewhat assuming the buoys can be positioned at different points in the wave. Two buoys would be somewhere in between. It may be that grid connection will only be possible if two or all three buoys are generating water pressure.

I guess the real question here is how smart the hydraulics are (do they have the ability to smooth out the pressure delivery to the generator).