Wave energy converter with air compression (wecwac)

Abstract

A wave energy converter with air compression (WECWAC) includes a cylinder and a piston located within the cylinder dividing the cylinder into an upper chamber and a lower chamber. The cylinder is fixedly attached to a spar whose up/down (heave) motion is restrained. The piston is fixedly attached to, and driven by, a float which moves generally in phase with the waves. Under typical wave conditions the piston functions to compress air within the upper chamber on its up stroke and within the lower chamber on its down stroke, i. e., the system is thus double-acting. In still water, the spar and cylinder combination is designed to drift down into the body of water relative to the piston whereby the size/volume of the upper chamber is decreased (while that of the lower chamber is increased). For small amplitude waves the piston continues to compress air in the upper chamber and this asymmetrical compression continues until the waves reach a predetermine level when 'double-action' is resumed. Controlling the position of the cylinder relative to the piston enables the WECWAC to automatically regulate its compression 'stroke' to suit varying wave conditions. The pressurized air from a WECWAC may be stored and/or processed to drive a turbo-generator or it may be combined with the outputs of other WECWACs to drive a single large and highly efficient turbo-generator.