Underwater energy harvesting to extend operation time of submersible sensors

A linear electromagnetic energy harvesting device for underwater applications, fabricated with a simple manufacturing process, was developed to operate with movement frequencies from 0.1 to 0.4 Hz. The generator has two coils, and the effect of the combination of the two coils was investigated. The experimental study has shown that the energy capture system was able to supply energy to several ocean sensors, producing 7.77 mJ per second with wave movements at 0.4 Hz. This study shows that this energy is enough to restore the energy used by the battery or the capacitor and continue supplying energy to the sensors used in the experimental work. For an ocean wave frequency of 0.4 Hz, the generator can supply power to 8 sensors or 48 sensors, depending on the energy consumed and its optimization.This work is co-funded by the project K2D-Knowledge and Data from the Deep to Space with reference POCI-01-0247-FEDER-045941, co-financed by European Regional Development Fund (ERDF), through the Operational Program for Competitiveness and Internationalization (COMPETE2020) and by the Portuguese Foundation for Science and Technology-FCT under MIT-Portugal Program. This work is also co-financed by Programa Operacional Regional do Norte (NORTE2020), through Fundo Europeu de Desenvolvimento Regional (FEDER), Project NORTE-01-0145-FEDER000032–NextSea, and by national funds through FCT–Fundação para a Ciência e Tecnologia, I.P. under project SONDA (PTDC/EME-SIS/1960/2020)