Empirical Study of Piezoelectric Energy Harvesting from Road Traffic Vibrations for Powering Street Lighting Sensors in Abuja

Energy harvesting from ambient vibration sources presents a renewable power strategy for ultra-low-power electronic systems in urban environments. This study conducts an empirical investigation of piezoelectric energy harvesting from road surface vibrations induced by vehicular traffic as a supplementary power source for wireless sensor nodes embedded in smart street lighting infrastructure in the Federal Capital Territory, Abuja. Polyvinylidene fluoride bimorph piezoelectric transducers are embedded in a road-surface mounting assembly installed at two road locations in Garki and Central Area districts, representing low and high traffic density sites respectively. Harvested electrical output is measured and characterized across a range of vehicle types, axle loads, and traffic speeds using a data acquisition system over four weeks. Power conversion conditioning electronics including a voltage rectifier, maximum power point tracking circuit, and energy storage supercapacitor are designed and optimized for the harvested power profile. Characterization data show peak power output of 3.8 milliwatts per transducer at the high-traffic site under heavy truck loading, with average power across the traffic day averaging 0.62 milliwatts. An energy budget analysis demonstrates that the harvesting system can power a ZigBee-based wireless luminaire control sensor node for a minimum of 18 hours per day at the high-traffic site. The study identifies the durability of piezoelectric transducer assemblies under repeated road loading as the critical technical barrier to long-term deployment and recommends an accelerated fatigue testing programme to validate transducer lifespan. Keywords: piezoelectric energy harvesting, road vibration, smart lighting, wireless sensor, Abuja