A power take-off apparatus for a wave energy converter of point absorber type, includes a cylinder attachable to a floating device, a piston that reciprocates inside the cylinder and has a piston rod attachable to a mooring, at least one penstock with a first end in communication with a second end of the cylinder through a first opening, and a second end having a second opening, and a housing above a cylinder first end. The housing communicates with the penstock through the second opening and with the cylinder through a third opening in the housing such that the cylinder, penstock and the housing form a closed loop for a fluid in the power take-off apparatus. A water turbine is arranged inside the housing so that working fluid entering the housing from the at least one penstock causes rotation of the water turbine to drive an electrical generator connected thereto.

A system and method for a for a wave energy converter device that is an axisymmetric point absorber which operates in a tension only condition over a large stroke that can operate in the given wave environment so as to eliminate the need for end stops in normal operation whereby the wave energy converter device has a floating hull with an interior Power Take Off (PTO) that uses an impedance control scheme for impedance matching with the wave environment in which it is deployed so as to maximize electrical power output as compared with a passively operating device of similar size.

A system and method for a for a wave energy converter device that is an axisymmetric point absorber which operates in a tension only condition over a large stroke that can operate in the given wave environment so as to eliminate the need for end stops in normal operation whereby the wave energy converter device has a floating hull with an interior Power Take Off (PTO) that uses an impedance control scheme for impedance matching with the wave environment in which it is deployed so as to maximize electrical power output as compared with a passively operating device of similar size.

A turbine comprises a shaft (20), a mass (10) eccentrically mounted for rotation about shaft (20), having its center of gravity at a distance from the shaft (20) and a motion base (15). Motion base (15) rigidly supports the shaft (20), and is configured for moving the shaft (20) in any direction of at least two degrees of movement freedom, except for heave. A floating vessel-turbine (120), encloses entirely the eccentrically rotating mass (10) and the motion base (15). The turbine converts ocean wave energy into useful energy, very efficiently.

The invention discloses a novel efficient power generation device of tide-wave energy, comprising a floating body provided on the sea surface, a support device provided on the coast, and a lever device connecting the floating body with the support device; the lever device comprises a force transmission rod and a main lever provided with a connecting device; the power generation device comprises a driving device, one end of which is connected with the connecting device to rotate the driving device and the other end is connected with the external electric motor device. The invention enables the up-and-down motions of the floating body through the acting force of the tide, to drive the up-and-down motion of the force transmission rod. The lever device connected with the support device by hinge, rotates the driving device through the connecting device, to rotate the external electric motor device to provide electric power.

A modular wave energy converter includes: a forward attachment frame; forward guide rails coupled to the forward attachment frame; a forward paddle coupled to the forward guide rails; and one or more forward tethers coupled to the forward paddle and the shaft. A combination of heave and surge forces from waves of water causes the forward paddle moves up and down the forward guide rails. The movement of the forward paddle moves the one or more forward tethers. The movement of the one or more forward tethers causes the shaft to rotate via the rotation of winches. The winches are configured with a one-way clutch, which allows the shaft to rotate in a first direction but not a second. The converter has the same structure on the aft side, including an aft paddle. The forward and aft paddles are positioned vertically or inclined.

A wave power generation system includes: a hydraulic pump device configured to operate by force of a wave to discharge an operating liquid to a main passage; a hydraulic motor device configured to be rotated by the operating liquid flowing through the main passage; a power generator configured to be driven by the hydraulic motor to generate electric power; and a heat exchanger device configured to perform heat exchange of the operating liquid. The heat exchanger device includes a heat exchange motor device connected to the main passage through a sub passage and configured to be operated by the operating liquid introduced through the sub passage, a refrigerant pump device driven by the heat exchange motor device and configured to suck and discharge a refrigerant liquid, and a heat exchanger to which the refrigerant liquid discharged from the heat exchange pump device and the operating liquid are introduced.

A system converts mechanical wave energy into electrical energy. The system includes a wave energy converter (WEC), which includes a surface float, a reaction structure, a plurality of flexible tethers, and a plurality of drivetrains. Each flexible tether connects the surface float to the reaction structure. Each drivetrain is connected to a corresponding flexible tether. Each flexible tether has a length established to treat the system as an inverse pendulum to utilize a horizontal surge motion of the surface float to present tension at the corresponding drivetrain for production of electrical energy from the horizontal surge motion.

A system converts mechanical wave energy into electrical energy. The system includes a wave energy converter (WEC), which includes a surface float, a reaction structure, a plurality of flexible tethers, and a plurality of drivetrains. Each flexible tether connects the surface float to the reaction structure. Each drivetrain is connected to a corresponding flexible tether. Each flexible tether has a length established to treat the system as an inverse pendulum to utilize a horizontal surge motion of the surface float to present tension at the corresponding drivetrain for production of electrical energy from the horizontal surge motion.

The present invention is a wave energy converter capable of extracting useful energy from ocean waves by utilizing finite depth of ocean waves, kinetic energy of flowing water and drag force of water that opposes the relative motion of the submerged body through the water, comprising two bodies attached to each other, wherein the buoyant body is moored to the seabed, and the fully submerged body is suspended from the buoyant body by vertical suspender cables, chains, ropes, other flexible lines, or a rigid frame, and placed at a depth of around one-half wavelength of the prevailing waves at the installation site, where the water is not affected by the surface wave action, therefore is still or relatively still.