A Hybrid Energy Harvesting System Based on Solar Radiation and Mechanical Vibration

Hybrid energy harvesting is a concept that can be applied to improve the performance of the conventional standalone energy harvesters. In this study, a hybrid energy harvesting device is presented that harvests energy from solar radiation and mechanical vibration by simultaneously combining the photovoltaic, piezoelectric, electrostatic, and electromagnetic mechanisms. The device consists of a bimorph piezoelectric cantilever beam having Lead Zirconate Titanate crystal layers on top and bottom surfaces of an Aluminum substrate. Two sets of comb electrodes (capacitors) are attached on two sides of the substrate. A permanent magnet is attached at the tip which oscillates within a stationary coil inside a casing. The exterior surface of the casing is covered by organic photovoltaic panel that captures energy from illumination. All the segments are interconnected by an electric circuit to generate combined output when subjected to solar radiation and mechanical vibration. Results for power output are obtained at the first resonance frequency of the beam with a common optimum load resistance. As the power outputs of all the mechanisms are combined, a high power efficiency can be achieved by the proposed hybrid energy harvester.