Numerical Modelling of a Piezo Roof Harvesting System: The Right Component Selection

The present work focuses on a first study for a piezoelectric harvesting system, finalized to the obtaining of electrical energy from the kinetic energy of rainy precipitation, a renewable energy source not really considered until now. The system, after the realization, can be collocated on the roof of an house, configuring a “Piezo Roof Harvesting System”. After presenting a state of art of the harvesting systems fromenvironmentalenergy,linkedtovibrations,usingpiezoelectricstructures,andof piezoelectricharvestingsystemsfunctioningwithrain,theauthorsproposeananalysis ofthefundamentalfeaturesofrainyprecipitationsforthedefinitionoftheharvesting system.Then,fourkeypatternsfortherealizationofapiezoelectricenergyharvesting systemarediscussedandanalysed,arrivingtothechoiceofacantileverbeamscheme, in which the piezoelectric material works in 31 mode. An electro-mechanical model forthesimulationofperformanceoftheunitfortheenergeticconversion,composed ofthreeblocks,isproposed.Themodelisusedforasimulationcampaigntoperform thefinalchoiceofthemoresuitablepiezoelectricunit,availableonthemarket,which willbeadoptedfortherealizationofthe“PiezoRoofHarvestingSystem”.