Comparison Among Different Rainfall Energy Harvesting Structures

A pioneering comparison of different piezoelectric materials finalized to investigate the possibility of energy generation by water droplet energy sources for low-power electronic devices was studied by Vatansever et al. in [5]. [...]the following has been presented in the literature, but never experimentally employed [16]. Internal impedance was set at 1 MΩ, in order to have an open circuit condition. [...]Figure 8 shows the different behaviors of the cantilever structure raindrops falling from a 2.0 m height. Roundy and Wright [27] described an equivalent electro-mechanical model for a piezoelectric cantilever; the stress given by the source (in the present case the raindrop) is correlated with voltage output by taking into account the piezoelectric strain coefficient, the electric field, the displacement field, the permittivity, the mass of the cantilever and inertia moment.