Integration of wave energy converters within floating offshore structures

Integration of Ocean Renewable Energy (ORE) devices within multi-use maritime structures stands as one potentially effective method to reduce the high Levelised Cost of Electricity (LCOE) currently associated with the sector. Integration within fixed structures such as breakwaters and sea-walls are feasible, but this is very much depth limited from an economic standpoint. The integration of ORE devices into floating structures allows for deployment in locations within both nearshore and offshore zones, where industries such as aquaculture and offshore wind are targeting in the next steps of their development.

This paper provides a summary of an experimental proof-of-concept investigation of a generic floating breakwater integrated with multiple Oscillating Water Column (OWC) wave energy converter devices. The investigation evaluates the performance of both the OWC devices and the breakwater for their respective purposes in both regular and irregular sea states. Parameters including device configuration, breakwater width, pneumatic damping and incident heading are investigated to establish the performance feasibility of such a concept. The results of the experimental investigation show benefits to the motions and transmission characteristics of the floating breakwater through OWC device integration, along with positive energy extraction capacities for the installed devices. The negative device interaction observed when installed with low spacing between devices and the subsequent performance enhancement through increased device spacing were key findings. These results provide a foundation for future development in floating structure integrated wave energy devices as the research looks towards mooring arrangements and array configurations of devices. The device applications are targeted at the offshore aquaculture industry as a form of energy generation and material/consumable storage solutions, along with multi-device coupling between floating offshore wind structures and wave energy converters.