A magnetically coupled piezoelectric ocean wave energy harvester for self-powered low-power appliances

The ocean contains abundant wave energy, which can be used as a new regenerative energy for power generation and provide energy for self-powered low-power appliances, realizing in situ energy utilization. Then, it can effectively promote the sustainable development strategy of the ocean and bring huge energy and social and environmental benefits. This paper proposes a magnetically coupled piezoelectric ocean wave energy harvester (MPWEH) system for wave energy harvesting. The MPWEH system includes four modules: energy harvesting, force magnification, piezoelectric power generation, and energy storage module. The energy harvesting module moves up and down in the tube body with the wave, effectively capturing and absorbing the wave energy and transforming the harvesting module’s motion into the interaction repulsive force between magnets. Then, the force magnification module amplified the magnetic force and applied it to the polarization direction of the piezoelectric ceramic to self-power the low-power appliances. This research carried out the feasibility verification experiment with the MPWEH prototype, and the results show that when the period is 3[Formula: see text]s, and the amplitude is 2[Formula: see text]m, the maximum voltage can reach 15[Formula: see text]V, and the maximum power can reach 12.85[Formula: see text]mW. Take Jiaozhou Bay Bridge as an example. The MPWEH system’s energy harvesting potential is studied, and the annual power generation of all the acquisition devices can reach 55.72[Formula: see text]kWh, which can be enough energy to supply the sensors on the cross-sea bridge.