Energy Harvesting From Waves Using Piezoelectric Floaters

Abstract

In this paper a wave energy converter (WEC) based on a segmented floating structure with embedded piezoelectric devices is numerically investigated. To illustrate the idea, a concept design based on assembling existing components is considered. The investigated system is made of three identical box-shaped slender floaters, interconnected by piezoelectric beams, aligned along the wave direction and moored to the seabed. The piezoelectric beams, bent alternatively by the oscillating relative motion of the floaters, constitute the power take-off (PTO) system to generate electricity. The numerical model is divided into two parts: a hydromechanical solver, describing the coupled motion of the floaters and the dynamics of the mooring lines, and a coupled electromechanical solver, which describes the behavior of the piezoelectric benders, including the associated resistive circuit. The coupling between these subsystems is one-way, because the WEC motion deforms the piezoelectric device without any electromechanical feedback on the floating structure. The developed numerical procedure allows for describing the basic features of the WEC response, for estimating the energy that can be generated by the device, and sets the starting point to explore the energy production capability of this kind of device.