Energy Harvesting Assessment Using PZT Sensors and Roadway Materials

The concept of utilizing networks of roads and highways for generating electricity has recently gained considerable attention; advances in the nanotechnology industry offer new opportunities for large-scale improvements in energy efficiency and energy production. In this field, Piezoelectric (PZ) energy harvesting technology has significant advantages over other renewable energy sources such as solar, wind, and geothermal. For example, the embedded roadway system produces little to no infrastructural footprint, and its energy generation span, on a busy highway, can continuously produce energy. However, current low-scale PZ manufacturing methods, and the lack of road-integrated PZ R&D, decrease the cost-effectiveness of this technology and may impact the mainstream adoption of piezoelectric systems. The primary objective of this project was to evaluate the technical feasibility of incorporating piezoelectric systems into roadways. The collaborative research team developed a lab-based Roadway Energy Harvesting System (REHS) using construction and piezoelectric (PZ) materials. The scope of the research project included investigation of the energy harvesting method, preparation of equipment and materials, durability tests of PZ materials and fabricating asphalt and concrete sections for structural and electrical testing. Structural and electrical characterization was completed by measuring the voltage generated in the sections, during a loaded wheel test (LWT), using an Asphalt Pavement Analyzer (APA.) Collected data and various plots developed using Matlab® revealed that deformation in asphalt was correlated to the produced electrical signal. The research results indicated that flexible roadway materials can produce more energy than rigid material such as typical concrete and Engineering Cementitious Concrete (ECC). Similarly, since typical concrete produced higher values than ECC, the magnitude of energy may be more related to strength and density than elasticity, especially in rigid material. Currently, the research team is developing a wafer box coupled with the pavement materials using a 3D printer on with CAD design. The results of this research project will contribute to the possibility of self-supporting energygenerating capacity for highways, for roadway sustainability.