A Hybrid Energy Harvester Based on Solar Radiation and Mechanical Vibration

In this study, a hybrid energy harvesting device is presented which simultaneously harvests energy from solar radiation and mechanical vibration using the photovoltaic, piezoelectric, and electromagnetic mechanisms. The device consists of a bimorph piezoelectric cantilever beam having Lead Zirconate Titanate (PZT) crystal patches on top and bottom surfaces of an Aluminum substrate. The tip of the cantilever beam has an attached permanent magnet which oscillates within stationary coils fixed to the top and bottom of a housing inside a casing. The exterior surface of the casing is covered by silicon photovoltaic panel that can capture energy from solar illumination. All the segments are interconnected by an electric circuit to generate a combined output when subjected to solar radiation and mechanical vibration. The hybrid prototype of the harvester is optimized by using finite element analysis to find the resonance frequencies and stress distributions. Results for power output are obtained at the resonance frequency of the hybrid beam using an optimum common load resistance. As the power outputs of all the mechanisms are combined, a high power output can be achieved by the proposed hybrid energy harvester.