Piezoelectric energy harvesting utilising flutter: An overview of angle, proximity and turbulence effects

It has been some time since a concept involving flutter of piezoelectric harvesters was introduced. A basic underpinning of how these harvester types operate in smooth, parallel-flow conditions has been realised in analytical, computational and experimental investigations. Preliminary findings show that these harvesters could potentially supplement more traditional wind-energy extraction methods, such as wind turbines based in urban environments. Also, this technology could be considered safer, quieter, and more aesthetically pleasing than urban-based wind turbines. Here, we present an overview of key findings by the authors to date with regards to piezoelectric flutter harvesters in the areas of flutter amplification, aerodynamic proximity effects, off-axis and turbulent flow, and the effect of the embedded hinge on harvester performance. In addition, a discussion takes place on future challenges with this technology, such as the proper quantification of harvester efficiencies, fatigue life, and methods by which harvester output may be increased. Despite future challenges, this technology shows potentiality and should be pursued further.