This paper introduces a new point-absorber wave energy converter (WEC) with a moonpool buoy—the moonpool platform wave energy converter (MPWEC). The MPWEC structure includes a cylinder buoy and a moonpool buoy and a Power Take-off (PTO) system, where the relative movement between the cylindrical buoy and the moonpool buoy is exploited by the PTO system to generate energy. A 1:10 scale model was physically tested to validate the numerical model and further prove the feasibility of the proposed system. The motion responses of and the power absorbed by the MPWEC studied in the wave tank experiments were also numerically analyzed, with a potential approach in the frequency domain, and a computational fluid dynamics (CFD) code in the time domain. The good agreement between the experimental and the numerical results showed that the present numerical model is accurate enough, and therefore considering only the heave degree of freedom is acceptable to estimate the motion responses and power absorption. The study shows that the MPWEC optimum power extractions is realized over a range of wave frequencies between 1.7 and 2.5 rad/s.

It is rather challenging to collect ocean wave energy at high efficiency because of its ultra-low frequencies and variable amplitudes. Triboelectric Nanogenerator (TENG) technology is more suitable for harvesting low-frequency than electromagnetic power generation technology. In this work, we designed a built-in cylindrical Triboelectric Nanogenerator (C-TENG) installed inside the ocean buoy (BUOY-41). The hydrodynamic properties of the C-TENG are consistent with the ocean buoy, which are calculated by CFD software (Star-CCM+). The Energy Capture Properties of the C-TENG are established by the finite element software (COMSOL). The C-TENG has high power density (30 mW/m²) and can meet the power demand of the ocean buoy (10 mW). The implementation of the present work is of great academic value and practical significance for the development of efficient marine renewable energy conversion technology, enhancement of marine equipment energy replenishment, enrichment of hydrodynamic theories and revealing of the complex mechanisms.