Combined wave energy converter and grid storage

A wave energy production apparatus for producing energy from the heave motion of the surface of a body of water, said apparatus comprising:

• one or more compression module(s) which comprise(s) a piston and a cylinder assembly;
• and a reciprocating assembly positioned around the compression module(s), which is operatively connected to cylinder(s), such that, in Generation Mode, reciprocates together with the cylinder(s) relative to the piston(s) of the compression module(s) due to the movement caused by the heave and sinking movement of the surface of the body of water, wherein said reciprocating assembly comprises at least one first weight changing mechanism comprising one or more dynamic compensation tank, which has at least one aperture with a closure configured to open and establish fluid communication between the dynamic compensation tank and the body of water in order to allow water to at least partially flood the dynamic compensation tank(s) when the water surface rises or heaves and the reciprocating assembly moves upward relative to the piston(s) and to close fluid communication between the dynamic compensation tank(s) and the body of water and retain water inside the dynamic compensation tank(s) when the water surface sinks and the reciprocating assembly moves downwards relative to the piston(s), wherein the cylinder(s) of the compression module(s) are configured to contain a fluid that is energised by the reciprocating movement of the cylinder(s), in Generation Mode, and said energised fluid is used to produce a fluid pressure that is eventually converted in electric energy.