In this video he talks about using BEST – buoyancy energy storage technology – for storage – the buoyancy of a container in a body of water. This is sort of the opposite of the pumped hydro storage. A 12 minute video.
What I propose is to use a similar system as a part of an offshore wind turbine. The base of the wind turbine would have a storage reservoir to hold pressurized air. The windmill would have a crankshaft that pulls up on a long connecting rod that transfers all of the wind power to the base of the tower. The reciprocating connecting rod would be moving the air pump pistons to compress the air. The pump could have a low pressure stage and a high pressure stage. The air would displace water out of the reservoir below the water surface. The depth of the reservoir determines the pressure.
With a single connecting rod, the blades and nacelle can rotate freely around the connecting rod. The rod’s up and down motion is not dependent on the direction of the blades. It would be best to have three rods pulling every 120 degrees of blade rotation. But the mechanism becomes more complicated in order to allow the nacelle to freely rotate around to point toward the wind. There would need to be some kind of slip rings to allow free rotation around the three connecting rods.
With three rods pulling every third of a rotation, each blade would be pulling the same load. Maximum power would be transferred to the pumps. Three stages of pumps to give high pressure to the reservoir. The depth of the reservoir determines the pressure. The reservoir would be best if it was shallow and wide to minimize the difference between empty and full pressures.