Energy-efficient characterization of solar panel-supercapacitors systems for energy-harvesting aware wireless sensor nodes

Emerging technologies for ambient energy harvesting have enabled the development of Energy-Harvesting Aware Wireless Sensor Networks. This paper presents a new energy efficient approach for the characterization of a system composed of a solar mini-panel and supercapacitors (supercaps) that is able to supply energy to the sensor node from the three possible sources, namely, the supercapacitor (supercap), the backup battery and the solar-panel itself. Besides the efficiency this approach preserves the integrity of the supercapacitors, avoiding the real risks of degradation usually found in the literature. It is also shown that the energy efficiency provides not only energy awareness sensor nodes, but also information for the analysis and planning of QoS metrics for Wireless Sensor Networks.