A shear mode piezoelectric energy harvester based on a pressurized water flow

A shear mode piezoelectric energy harvester for harnessing energy from pressurized water flow is developed. It converts flow energy into electrical energy by piezoelectric conversion with oscillation of a piezoelectric film. A finite element model is developed in order to estimate the generated voltage of the piezoelectric film subjected to a distributed load. Prototypes of the energy harvester are fabricated and tested. Experimental results show that an open circuit output voltage of 72 mVpp and an instantaneous output power of 0.45 nW are generated when the excitation pressure oscillates with an amplitude of 20.8 kPa and a frequency of about 45 Hz. The solution of the generated voltage based on the finite element model agrees well with the experiments. Based on the finite element model, the effects of the piezoelectric film dimensions, the water pressure and types of piezoelectric films on the output voltage of the harvester can be investigated.