Carbon footprint of piezoelectrics from multi-layer PZT stacks to piezoelectric energy harvesting systems in roads

Piezoelectric energy harvesting devices (PEHDs) for road installation are being researched as potentially low-emission electrical generators, but their life cycle greenhouse gas (GHG) emissions must be assessed to guide their design and implementation toward minimizing their carbon footprint. Parametric life cycle assessments (LCAs) of a PEHD, its generator, and the piezoelectric material were performed using data from a pilot-scale PEHD installation. The GHG emissions of the lead zirconate titanate (PZT) piezoelectric stack were determined to be lower than previously reported in the literature at 10.81-15.90 kg CO_2eq/kg piezoelectric. The GHG emissions of electricity generated by a PEHD range from 48.65-588.63 g CO_2eq/kWh, spanning from similar to renewables to slightly higher than electricity from natural gas. Sensitivity analysis indicated that spatial parameters and the device lifetime had the largest influence on the LCA results. PEHDs installed on roads show potential to be low-GHG emission energy systems.