Abstract: A hydrokinetic water turbine system includes two turbine assemblies each having a frame structure, a horizontally-disposed shaft supported by the frame structure, and a rotor secured to the shaft. The rotor has a plurality of spaced-apart blades so that the flowing stream of water revolves the rotor. The blades are filled with a foam material to reduce weight and increase buoyancy. The frame structure is an open frame structure and includes frame members adapted to reduce a coefficient of drag of the frame structure. The frame members are filled with a foam material to reduce weight and increase buoyancy. The two turbine assemblies are secured side by side with shafts coaxial and the rotors rotating in opposite directions. The shafts can drive electric generators located out of the water or under the water. The underwater generators can be direct drive, low speed, high output generators.

Abstract: A hydrokinetic water turbine system includes a frame structure, first and second shafts rotatably supported by the frame structure, and first and second rotors secured to the first and second shafts respectively and each having a plurality of spaced-apart blades so that the flowing stream of water revolves the first and second rotors about a central axis of the first and second shafts respectively. The first and second shafts are horizontally-disposed and coaxial and the first and second rotors are adapted to rotate in opposite directions. The blades are hollow and filled with a foam material to reduce weight and increase buoyancy. The frame structure is a substantially rectangular and open frame structure and includes frame members adapted to reduce a coefficient of drag of the frame structure. The frame members can be hollow and filled with a foam material to reduce weight and increase buoyancy.