Hydrodynamic characteristics of a wave energy converter array-offshore aquaculture cage group hybrid system

Abstract

Integrating an array of wave energy converters (WECs) with offshore aquaculture cages offers a sustainable solution for meeting daily energy demands while enabling the sharing of mooring systems. This paper investigates this unanswered question by numerically simulating a hybrid system composed of an array point-absorber WECs and a moored aquaculture cage group. The multi-body and multi-coupling interaction among WECs, mooring chains, cage nets, floating collars and cage sinkers are investigated. The results reveal that, across all simulated wave periods, rear-positioned WECs exhibit higher wave energy conversion efficiency than front-facing units, primarily due to the reduced constraints imposed by the mooring chains. Compared with taut mooring, the catenary mooring configuration increases wave energy conversion by 50 % in long-period waves and reduces facing-wave mooring tension by 13 %. Under identical physical parameters, square and in-line cage configurations demonstrate superior wave energy conversion performance, whereas front–back arrays induce greater mooring tension. PTO units partially offset the mooring tension, so the optimal PTO damping for WECs in the hybrid system is higher than for isolated WECs and increases along with wave propagation. These findings offer valuable insights for the engineering implementation of renewable energy-offshore aquaculture hybrid techniques in the development of marine ranching.