Design and Implementation of Hybrid Micro Energy Harvester for Autonomous WSN Components

Successful deployment of Wireless Sensor Network (WSN) depends on the availability of power sources. Conventional battery-based WSN components has several drawbacks, such as limited life-span, bulky size and hazardous to the environment. Hence, energy harvesting from ambient sources attracts enormous attention. But energy harvesting depends on the availability of the ambient sources. In most cases energy harvesting from a single source is not enough to produce sufficient energy to power up WSN components. This paper describe about the design, and implementation consideration of a hybrid energy harvester for an autonomous sensing system. The sensing components of WSN are connected with the hybrid energy harvester on the same structure to generate required energy from the ambient environment such as solar and chemical reaction. As a case study, the power requirements of in-house developed WSN components [1] are measured. Based on the power requirement a hybrid energy harvester based autonomous system is designed [2], and a functional prototype of the system is implemented. In the implemented prototype, energy is being harvested from the ambient solar and chemical sources. From the evaluation of the developed system, it is found that powering WSN components, hybrid energy harvester produces an additional amount of 10491.93 J (equivalent to 2.91 Wh) of energy, which is capable to fill-up a 971 mA-hr storage in one day operation. This is enough for the WSN components to draw power subsequently, when there is not enough ambient sources available for next few days.