A compact and homologously excited hybrid energy harvester to scavenge fluid kinetic energy in pipelines for powering low-power sensor systems

The safe transportation of pipeline gas represents a critical issue in field of gas transport. To overcome the problems of environmental pollution and economic cost, which result from the utilization of dry batteries to power the sensors and other related low-power electronic devices, a hybrid energy harvester based on the piezoelectric, electromagnetic, and triboelectric mechanisms has been proposed. The relative motion of the rotor-stator structure and the elastic support can be utilized, the three different energy harvesting mechanisms can be excited simultaneously by the shaft rotation. This homologously excition approach makes the excitation more efficient and can increase the electrical output within a limited structure. It is experimentally demonstrated that the three mechanisms can work synergistically in a limited space, and the output power is effectively enhanced by the hybrid operation, compared to that of the single mechanism operation. The output power of the hybrid energy harvester is 2.52 mW at an external load of 10 kΩ. It is demonstrated that the energy harvester can successfully power a wireless temperature and humidity sensor, LEDs for nighttime illumination, etc. This suggests that the energy harvester may offer a novel approach for monitoring the safety of pipeline gas transportation.