A heaving point absorber-based ocean wave energy convertor hybridizing a multilayered soft-brush cylindrical triboelectric generator and an electromagnetic generator

Abstract

Abstract Ocean wave energy is one of the inexhaustible and most prospective renewable energy resources, but its low frequency and irregular amplitude challenge the typical wave energy converters (WECs). This work presents a heaving point absorber-based WEC for potentially harvesting ocean wave energy. The design comprises a heaving buoy, a transmission mechanism and an encapsulated magnetic-coupling triboelectric-electromagnetic hybrid generator. The heaving motion of the buoy driven by waves is transferred into a unidirectional rotation of the rotator of the generator via the transmission mechanism, and thus electricity is produced. The hybrid generator consists of a multilayered soft-brush cylindrical triboelectric nanogenerator (MBC-TENG) and a rotary disc electromagnetic generator (RD-EMG). The designed multilayered structure can increase the space utilization of the WEC, and the soft brushes can highly improve the output performance and durability of MBC-TENG. The magnetic coupling makes MBC-TENG easy to be hybridized with RD-EMG and fully isolated from the external environment to ensure the stable output performance of the generator. The electrical output characteristics of the hybrid generator, as well as its robustness, are systematically studied. Finally, a wave tank experiment is conducted to demonstrate the feasibility and practicability of the WEC as a power source. This work renders a potential approach towards effective ocean wave energy harvesting and versatile applications.