A wind generator has a first propeller (3) for the rotor of a generator whose stator is also rotated, this being done by a second propeller (4) on the opposite side of the generator. It spins the stator in the reverse direction to that of the rotor. A hydro-generator has the same principle of operation, except that there is a contra-rotating stator turbine wheel on the same side as the rotor turbine wheel as well as a stator turbine wheel on the far side. The rotor and stator shaft ends are joined to their respective turbine wheels inside housings. The rotor runs in stator bearings at its non-turbine wheel end and the stator runs in rotor bearings at the other end.
