Piezoelectric Energy Harvester With Shape Memory Alloy Actuator Using Solar Energy

A piezoelectric cantilever beam-based energy harvester working with solar energy is proposed in this paper. The piezoelectric cantilever beam is excited by a shape memory alloy (SMA) spring actuator. The heating and cooling of the SMA actuator is done by designing an appropriate piping and transport system with water as a working fluid. The frequency and amplitude of excitation force exerted by an SMA actuator to the piezoelectric cantilever beam depend on the flow rate of water used for heating and cooling of SMA and the temperature of the water. The energy harvester is modeled analytically and fabricated to evaluate its performance in the laboratory. The analytical and experimental results show that higher output voltage from the energy harvester can be obtained with higher water temperature and frequency of the output voltage is limited to the dynamics of the SMA actuator. The voltage generated with the proposed energy harvester at the flow rate of 24 ml/s with the temperature of 70 °C is found to be 12 V. The harvester utilizes only the solar energy for its operation and hence the proposed design is a new addition to the area of energy harvesting using piezoelectric cantilever beam.