Windmill should not be rated in watts since it is mechanical energy, should be n-m or J
I spent a while before I gave up on trying to get my pump jack to work using the windmill. Then i searched the forum and see that the windmill is mechanical energy and not electrical, yet is is rated in watts. You should use a different unit to differentiate mechanical energy from electrical energy. It should be in newton-meters (n-m) or joules (J)
This would be a good clue to the player that it isn't a viable power source for non mechanical things.