Energy output of piezoelectric transducers and pavements under simulated traffic load

Abstract

Piezoelectric technology introduced to pavement structures can transform the potential renewable mechanical energy in the road into electrical energy, and this provides new ideas for solving the energy supply problem of green and intelligent transportation. The purpose of this study is to quantify the energy output of piezoelectric transducers under vehicle load and thereafter estimate the daily energy output of piezoelectric pavements. The loading process and the energy output model of piezoelectric transducers are analyzed and established, respectively. Through numerical analysis, the energy output variation laws of these transducers are evaluated in three aspects: load, speed, and resistance. The energy output is estimated based on the daily traffic volume statistics. The layout of piezoelectric transducers on the piezoelectric pavement is designed, and the economic benefit of piezoelectric pavements is preliminarily analyzed. Results show that the larger loads and the faster speeds of vehicles, the larger the energy power. One piezoelectric transducer can output 0.058-J energy in a single 0.7-MPa loading. However, higher output power does not guarantee a higher energy output. The maximum energy output occurs at the optimal vehicle speed which is influenced by resistance, but the maximum energy output remains the same at different optimal speeds. By increasing the resistance, the energy output of piezoelectric transducers can reach the maximum at a low speed. Under the daily traffic volume, the energy output of a single piezoelectric transducer can reach 963.99 J, and the daily energy output of a 100-m piezoelectric pavement is approximately equal to the total battery power of 35 mobile phones. Clean energy harvesting in the pavement has broad prospects by using piezoelectric technology, but the energy output of road piezoelectric transducers still needs to be further improved.