Design and Experimental Validation of a Piezoelectric Impact-Based Energy Harvester for Low-Frequency Oceanic Waves

This paper presents the design and experimental validation of a novel impact-based piezoelectric energy harvesting system tailored for low-frequency oceanic waves prevalent in shallow coastal regions such as Cox’s Bazar, Bangladesh. The project employs a triangular-frame structure housing five vertical pipes, each containing stacked PZT-5A piezoelectric discs, impact balls (e.g., golf or steel balls), and MEMS vibration sensors to capture bidirectional wave motion. Laboratory experiments under simulated marine conditions (0.1–2 Hz wave frequency, 3.5% salinity) demonstrate that steel balls (70 g) paired with rigid cement base tiles and double-disc piezoelectric configurations yield the highest output-up to 1.28 V per pipe and ~20 mW per wave event. The system’s modular architecture enables scalability for powering low-energy marine electronics, including navigation buoys and coastal IoT sensors. Techno-economic analysis reveals a levelized cost of energy (LCOE) of ~$840/kWh in its current form, but a compelling 2.1-year payback period and 38.9% ROI when deployed to replace battery-powered offshore sensors. Environmental assessment highlights the need to address lead toxicity in PZT through robust encapsulation or transition to lead-free alternatives like BaTiO₃. Results confirm the feasibility of this simple, solid-state harvester as a sustainable solution for micro-power generation in remote marine environments.