A static-dynamic energy harvester for a self-powered ocean environment monitoring application

Ocean intelligent buoy is important for ocean environment monitoring. With the increase of requisite sensors and transportable data, a long power supply has become a problem to be solved urgently. In this work, a hybrid nanogenerator integrating triboelectric, piezoelectric, electromagnetic, photovoltaic, and thermotropic units is proposed to maximize ocean ambient energy harvesting, which includes static energy (solar and thermal energy) and dynamic energy (wave energy). Compared with a device with a single energy conversion mechanism, this structural design breaks the limit of harvesting time and natural conditions during the energy harvesting process, thereby increasing the harvested energy. Static energy harvesting is realized by the thermoelectric (TG) and photovoltaic (PV) units located inside the device and the PV unit attached to the device surface. Results show that the maximum open-circuit voltage and short-circuit current are 5 V and 41 mA in the external PV and 1.33 V and 49 mA in the internal PV under 30000 Lux illumination, respectively. The open-circuit voltage and short-circuit current of the TG unit are 5 V and 15 mA, respectively. The core component of the dynamic generation unit is the gimbal used to harvest wave energy by the triboelectric nanogenerator (TENG), piezoelectric generator (PENG), and electromagnetic generator. When the frequency is 2.4 Hz, the maximum peak-to-peak power of the TENG, PENG, and EMG are 0.25, 1.58, and 13.8 mW, respectively. Finally, an intelligent ocean buoy is fabricated by the integration of an energy harvester, a power management circuit, sensors, a microcontroller, and a wireless communication module. Driven by static and dynamic energy, temperature signal, humidity signal, GPS signal, and sound signal are sent to the receiving terminal wirelessly. The ocean energy harvester proposed in this work is of great significance for ocean energy harvesting and ocean wireless monitoring systems.

Automated summary

This paper proposes a hybrid nanogenerator that maximizes ocean ambient energy harvesting, integrating triboelectric, piezoelectric, electromagnetic, photovoltaic, and thermotropic units. By utilizing both static and dynamic energy, an intelligent ocean buoy is fabricated, which can wirelessly transmit temperature, humidity, GPS, and sound signals to the receiving terminal.