Well, the thing is, I don't know how efficient them windmill rotors are. They got high solidity but I'm pretty sure a high tip-speed-ratio three-blade rotor is more efficient. Like a Jake 23-10 has a 7 meter (23 foot) diameter rotor and they produce about 15hp at the shaft @ 25 mph and run at TSR8. A Jake 31-20 is a 9.4 meter (31 foot) diameter machine and they can produce about 30hp at the shaft @ 25 mph and also run at TSR8.
A Jake grid-tie turbine would be ideal to drive a hydraulic pump. It already has an angle gearbox and the generator is driven by a truck driveshaft. Just remove the generator and replace it with a pump. But I don't know why anybody would want to do that. You'd need a PFC pump so it could run at any speed and deliver constant pressure and flow, and that means running a signal line to the pump's compensating port for the swashplate. And then with hydraulics you got slippage in the pump, slippage in the motor, restriction in the lines and by the time you get everything said and done you lose roughly 50% of all the input power to the pump in heat. There's a reason hydraulic systems need coolers and they get so hot you can't even touch a line without getting burnt.
I mean, my CaseIH Magnum tractors got nine-cylinder axial PFC pumps - 75 gpm @ 3,000 psi. And standby pressure is 540 psi at zero flow. The hydraulic system in one of those holds 175 gallons of oil and within one hour running a couple little 1.5 gpm vac motors @ 3,000 psi on a planter the oil temperature reaches 200 degrees F. I'll let you do the calculations on that on how many BTU's it takes to heat 175 gallons of hydraulic oil from ambient to 200F just to run a couple vac motors that total about 5hp power requirement. That's your input power being turned to heat in return for the flexibility and reliability of using hydraulics for a remote power source.
