An electromagnetic energy harvesting device based on high efficiency windmill structure for wireless forest fire monitoring application

In this paper, we introduce a miniature windmill-structured energy harvester for wireless monitoring of forest fires. The proposed energy harvester design can effectively scavenge the energy from ambient air flow using electromagnetism, thereby self-powering the wireless sensing nodes for fire alarming. To find an optimal structure with the highest aerodynamic efficiency and sensitivity to wind flow, miniature energy harvesters with various windmill structures were designed, simulated, 3D printed and experimentally characterized. In the performance test, with the optimized windmill structure, a peak output voltage of 5.2 V and a peak output power of 60 mW were achieved by the energy harvester with a load resistance of 150 Ω. Moreover, a wireless transmission module was designed and connected to the windmill-structured energy harvester to constitute a wireless fire monitoring system. This module successfully transmitted an alarm signal upon detection of a fire in the feasibility test.