Abstract: A closed-loop hydraulic apparatus 200 for converting wave energy comprises a pump 201 for pumping a fluid through the apparatus 200. The pump 201 includes a body 202 defining a chamber 203, and a piston 207 that partitions the chamber 203 into a working side 208 and a blind side 209. A buoyant actuator is connected to the piston 207. An inlet 64 is connected to the working side 208 of the chamber 203 so that the fluid is able to flow from the inlet 64 and into the working side 208 of the chamber 203. An outlet 63 is connected to the working side 208 of the chamber 203 so that the fluid is able to flow from the working side 208 of the chamber 203 to the outlet 63. A hydraulic controller 102 is operable to control the pump 201 by controlling the pressure of the fluid at the inlet 64 and the outlet 63 so as to optimise the output of the pump 201 in response to tidal variations and/or sea state. The pressure of the fluid at the inlet 64 and the outlet 63 is controlled in accordance with a control algorithm.

Abstract: A wave energy conversion system for harnessing wave energy in a body of water and converting the harnessed wave energy to pressurized fluid, and also a method of deploying such a wave energy conversion system. The wave energy conversion system comprises a unit including a buoyant structure responsive to wave motion, at least one pump and at least one tether adapted to be operably connected between the pump and a fixture below the unit, whereby movement of the buoyant structure relative to the fixture in response to wave motion converts harnessed energy to pressurized fluid. The unit is adapted to be deployed by moving the tether into coupling engagement with the fixture upon actuation of the pump in a manner causing movement of the tether into engagement with the fixture.

Abstract: An apparatus is provided for harnessing ocean wave energy, wherein the apparatus relieves excessive loadings on components to avoid damage thereof in adverse wave conditions. The apparatus includes a buoyant actuator and a pump anchored within the body of water. Fluid at high pressure is pumped ashore by the pump, energy is extracted as useful work at an on-shore plant, and the resultant reduced pressure fluid is returned to the offshore pump to be re-energized. The buoyant actuator is operably connected to the pump by tether and is buoyantly suspended within the body of water above the pump. The buoyant actuator is provided with a connector that includes a damping mechanism configured to maintain a substantially rigid connection between the hollow body and the tether until such time as loading therebetween exceeds a prescribed load whereupon the damping mechanism facilitates limited relative movement therebetween to relieve the loading.

Abstract: A buoyant actuator (19) for coupling wave motion to a device operable in response to wave motion in a body of water. The buoyant actuator (19) comprises a generally spherical body (20) defining an exterior surface and a hollow interior adapted to contain water received from the body of water. The exterior surface comprises a plurality of facets (101) which are tessellated. Typically, there are 36 facets (101), of which 12 comprise generally pentagonal facets (105) and 24 comprise generally hexagonal facets (107). The body (20) comprises a plurality of openings (143) for fluid flow between the hollow interior and the surrounding body of water. A closure configured as a flap (145) is provided for each opening (143) to block or at least inhibit fluid flow therethrough, the closure being adapted to move away from the opening to permit fluid flow therethrough in response to a predetermined fluid pressure differential imposed thereon between the hollow interior and the surrounding body of water.

Abstract: Apparatus (10) for harnessing ocean wave energy and for converting the harnessed energy to high pressure sea water, typically above 100 psi and preferably above 800 psi. The high pressure seawater generated by the apparatus (10) can be piped to shore for use in any appropriate purpose. The apparatus (10) comprises a float (12) buoyantly suspended within the body of seawater (1) and a pump (13) operatively connected to the float (12). The pump (13) comprises an intake chamber (47), a discharge chamber (49) and a piston (61) extending between the intake and discharge chambers (47, 49). The piston (61) comprises a tube (63) having a flow passage (102) extending between the intake and discharge chambers (47, 49). The piston (61) and discharge chamber (49) cooperate to define a pumping chamber (100) adapted to undergo expansion and contraction in response to reciprocatory motion of the piston. The piston (61) is operatively connected to the float (12) to be driven by upward movement of the float.

Abstract: A closed-loop hydraulic apparatus 200 for converting wave energy comprises a pump 201 for pumping a fluid through the apparatus 200. The pump 201 includes a body 202 defining a chamber 203, and a piston 207 that partitions the chamber 203 into a working side 208 and a blind side 209. A buoyant actuator is connected to the piston 207. An inlet 64 is connected to the working side 208 of the chamber 203 so that the fluid is able to flow from the inlet 64 and into the working side 208 of the chamber 203. An outlet 63 is connected to the working side 208 of the chamber 203 so that the fluid is able to flow from the working side 208 of the chamber 203 to the outlet 63. A hydraulic controller 102 is operable to control the pump 201 by controlling the pressure of the fluid at the inlet 64 and the outlet 63 so as to optimise the output of the pump 201 in response to tidal variations and/or sea state. The pressure of the fluid at the inlet 64 and the outlet 63 is controlled in accordance with a control algorithm.

Abstract: A buoyant actuator (10) is used in apparatus (11) for harnessing wave energy in a body of water such as the ocean. The buoyant actuator (10) is deployed within the body of water (12) and is responsive to wave motion in the body of water. The buoyant actuator (10) includes a body (101) incorporating a flow path along which water can flow, and a gate means (115) for controlling flow along the flow path. The gate (115) includes closure elements configured as flaps (221) providing a barrier (222) across the flow path through the body (101). Each flap (221) is moveable into and out of a condition in which it cooperates with the other flaps (221) to provide the barrier (222). A latch mechanism (231) is provided for releasably retaining each flap (221) in the condition providing the barrier (222). The latch mechanism (231) has a magnetic coupling.