1. Voith-Schneider rotors © www.tidalflowenergy.com

2. A Voith-Schneider rotor may be used for extracting one-way river flow energy or extracting two-way tidal flow energy

3. the rotor has almost all of its components above the water level the generator is also above water level the rotor blades can reach to almost the full depth of the water channel very large sized rotor blades suffer from cavitation

4. A Voith Schneider rotor fitted in a venturi channel in a river © clf anderson rotor blade and guide vane shapes are diagrammatic only not to scale plan view of venturi casing river flow blade control rods this rotor has high efficiency but is complicated and expensive control rod anchorage rotor runs clockwise it is inherently self regulating on loss of electrical load positive displacement modeon this side of the channel each blade is “feathered”to travel against the flow

5. the rotor may be used in small tidal channels © clf anderson rotor blade and guide vane shapes are diagrammatic only not to scale flood tide blade control rods the control rod anchorage must be reversed at slack water control rod anchorage rotor runs clockwise plan view of venturi casing lost water flow energy otherwise the rotor will run in alternate directions on each tide

6. change of control rod anchorage maintains the same direction of rotation for both directions of current flow which permits the use of roller clutches to allow the generators to motor ahead of the rotor at slack tide © clf anderson rotor blade and guide vane shapes are diagrammatic only not to scale venturi casing ebb tide control rod anchorage has been reversed rotor runs clockwise lost water flow energy most of the engineering and all of the electricals are above the water