Harvesting Wind Energy Using a Galloping Piezoelectric Beam

Galloping of structures such as transmission line supports and bridges is a classical aeroelastic instability phenomenon that has been looked upon as a harmful and destructive effect. However, there exists potential to harness useful energy from this phenomenon. The study presented in this paper focuses on harvesting wind energy that is being transferred to a galloping beam. The beam has a rigid tip body with a D shaped cross section. Piezoelectric sheets are bonded on the top and bottom surface of beam. During galloping, vibrational motion is input to the system due to aerodynamic forces on the D-section, which is converted into electrical energy by the piezoelectric (PZT) sheets. The significance of various parameters in the system such as wind velocity, material properties of the beam, electrical load and beam natural frequency is discussed. Experimental and analytical investigations of power output are performed on a representative device. A maximum output power of 1.14 mW was measured at a wind velocity of 10.5 mph. A potential application for this device is to power wireless sensor networks on outdoor structures such as bridges and buildings.