An investigative study of a wave-energy device

This paper presents the methodology and design of an offshore float device to capture the power in waves. Results, both experimental and theoretical, reveal that a simple modification of a mechanical cycle can lead to a significant increase in the energy that is developed. A prototype device, to be tested on the Great Lakes, is presented with experimental results obtained from laboratory testing. The responses of the prototype system are correlated to illustrate that wave power can provide significant amounts of energy. The novel method analyzed, when employed on other float devices, increases the energy output of the system. The recovery concept presented increases the deliverable energy that can be captured from a bouyant float following the free passage of a wave: this is accomplished by sequential capture (preloading) and release of the buoyant float at critical stages of wave passage. Displacement-work-energy concepts presented illustrate that preloading a float in the trough of the wave and subsequent release of it under the wave crest, as a mechanical cycle, can lead to a return of more energy than was required to preload the float and provide a net increase of energy that might be extracted from a wave alone.