Spherical electret generator for water wave energy harvesting by folded structure

With the increasing demand for energy resource, the development of marine energy harvesting technology has attracted widespread attention. Herein, a spherical electret wave power generator is designed and constructed for ocean wave energy harvesting. Based on electrostatic induction from electret material, the generator converts wave energy into electric energy through the bias voltage of the folded electret power generation unit. With ultra-low excitation frequency at 2Hz, the peak-to-peak output voltage and output power can be reached up to around 300 V and 20 mW, respectively. Compared with other traditional wave energy generators, the utilization of space in the sphere is improved by the folded structure, which also has the advantages in terms of simple structure, high-energy conversion efficiency, light weight and small size. The generator is also capable of collecting low-frequency vibration energy in random directions, as well as realizing large-scale power supply after deploying an array of structures.