Recent Progress on Underwater Energy Harvesting Technology for Powering Observation Networks

Abstract

Underwater stereo observation networks are critical for acquiring a real-time awareness of the environment, targets, and underwater activities. It forms an essential foundation for national marine security, subsea resource exploitation, and early warning of marine disasters. Traditional battery-based power supplies are becoming increasingly inadequate for supporting the long-term sustainable operation of observation networks. To improve the endurance of underwater observation devices, it is highly desirable to develop in-situ underwater energy harvesting. Because underwater current energy and underwater wave energy have the advantages of extensive distribution, good consistency, and high-power density, this study focuses on the recent progress in underwater current energy and underwater wave energy harvesting for powering underwater observation devices. Based on the differences in energy transfer types, this review summarizes and compares representative studies on underwater energy harvesters based on electromagnetic generators, piezoelectric nanogenerators, triboelectric nanogenerators, and hybrid generators. Furthermore, this review presents the prospects for the future development of underwater energy harvesters. This paper provides an idea for the innovation of in-situ energy supply technology for underwater observation networks.

Keywords

• underwater energy
• energy harvesting
• underwater observation network
• in-situ energy supply