Power reclamation efficiency of a miniature energy-harvesting device using external fluid flows



This study represents experimental results related to the energy-harvesting capability of a miniature power reclamation device based on external liquid flows. The device's reclamation principle depends on the conversion of mechanical energy into electrical energy. The mechanical energy in the device was generated by capturing vibrations caused by external liquid flows via the device's tails, which were designed by taking inspiration from the body shape of the black ghost knife fish, Apteronotus albifrons. The reclaimed power was obtained through magnetic polarization, which was generated by rotating circular waterproof magnet structures as a result of rotating movements of the mentioned tails and is transferred to 3.76 V (Ni-Mg) batteries. Power reclamation was also simulated using COMSOL 4.2a software in order to compare the maximum reclaimable theoretical energy-harvesting capacity with the experimental results. Experimental tests were performed within a range of flow velocities (1.0 ~ 5.0 m/s) for various fluid densities (plain water, low-salt water and high-salt water) in order to obtain extensive experimental data related to the device in response to external fluid flows. According to experimental results, the device could generate powers up to 17.2 W. On the other hand, the maximum reclaimable power was obtained at 25.7 W from COMSOL Multiphysics 4.2a simulations. Promising energy harvesting results imply that the output from this device could be used as a power source in many applications such as in lighting and global positioning system (GPS) devices. Copyright © 2014 John Wiley & Sons, Ltd.