Advanced ocean wave energy harvesting: current progress and future trends

With a transition towards clean and low-carbon renewable energy, against the backdrop of the fossil-energy crisis and rising pollution, ocean energy has been proposed as a significant possibility for mitigating climate change and energy shortages for its characteristics of clean, renewable, and abundant. The rapid development of energy harvesting technology has led to extensive applications of ocean wave energy, which, however, has faced certain challenges due to the low-frequency and unstable nature of ocean waves. This paper overviews the debut and development of ocean wave energy harvesting technology, and discusses the potential and application paradigm for energy harvesting in the "intelligent ocean." We first describe for readers the mechanisms and applications of traditional wave energy converters, and then discuss current challenges in energy harvesting performance connected to the characteristics of ocean waves. Next, we summarize the progress in wave energy harvesting with a focus on advanced technologies (e.g., data-driven design and optimization) and multifunctional energy materials (e.g., triboelectric metamaterials), and finally propose recommendations for future development.