Hybrid Solar-RF Energy Harvesting Mechanisms for Remote Sensing Devices

Recently, sensor networks effectively provide many applications in different fields. The deployment of mobile sensors, unmanned aerial vehicles is to reduce the burden of energy consumption for sensor nodes. However, saving energy in such networks is still a critical issue. This paper investigates the performance of a hybrid RF-Solar harvesting circuit for remote sensing devices. The harvesting circuit can simultaneously harvest power from solar and radio frequency (RF) sources readily available in the surrounding environment. The proposed work builds RF and solar harvester circuits to create hybrid harvesting circuits for all elements in the combined sensing networks. The stand-alone RF harvester circuit is a dual-band multi-stage harvester that is designed to work at 2.4GHz, Wi-Fi/WLAN bands. The standalone solar harvester circuit comprises a solar panel with a maximum power point tracking (MPPT) algorithm. The whole hybrid system can produce a maximum power of up to 133.25W with a boost current element in the charging system. Since each node is equipped with a rechargeable battery, all the batteries are charged by the harvested power from the proposed circuits. This approach supports the operation of the networks safe and continuous even when a shortage of harvested power happens due to bad conditions such as cloudy or rainy days. This work shows promise and is applicable.