Harvesting Human Footstep Energy for Sustainable Electrical Power Generation and Storage Using a PZT-Based Piezoelectric Floor Tile

This study presents the design, fabrication, and experimental characterization of a low-cost piezoelectric floor tile for converting intermittent human-footstep loading into electrical energy and delivering that energy through a complete conditioning and storage pathway. The prototype integrates thirty 27 mm lead-zirconate-titanate (PZT) discs in a 5-series × 6-parallel configuration on an 11 × 11 in. mechanical platform. The electrical output is processed through a full-wave bridge rectifier, a 1000 µF filter capacitor, and a buck–boost converter regulated to approximately 5 V before entering the downstream battery-protection/charging stage and 3.7 V lithium-ion storage. Under the reported laboratory loading conditions, output voltage increased from 8.2 to 20.0 V and current from 1.5 to 5.0 mA as the applied load increased from 20 to 60 kg, producing calculated electrical power from 12.3 to 100 mW. For the 0.0781 m² prototype footprint, the maximum calculated output corresponds to 1.28 W m⁻². The constant-load test showed a narrow voltage range of 19.8–20.1 V over 50 s. During a 100–1000 Ω resistance sweep, voltage increased while current decreased, with the highest calculated load power within the tested range occurring at 100 Ω. Battery-terminal voltage increased from 3.20 to 3.70 V during a 30 min repeated-excitation test. Surface-treatment experiments showed that graphite reduced calculated output power to 57.6 mW, whereas silver and RTV silicone produced approximately 100.5 and 97 mW, respectively. These results demonstrate the feasibility of integrating low-cost PZT transducers, mechanical force transfer, power electronics, energy storage, and a functional LED load in a single floor-tile platform. The study is positioned as a laboratory proof of concept; practical deployment will require calibrated pedestrian testing, energy-per-step measurements, conversion-efficiency analysis, long-term cycling, and field validation.