Estimation of the harvestable power on wireless sensor nodes

Wireless sensor networks (WSNs) are typically used to measure physical quantities of their environment at locations characterized by poor accessibility and lacking of wired infrastructure. To extend the operational time, energy harvesting systems (EHSs) support the power supply by transforming environmental energy into electrical energy. In the best case, a self-sufficient supply of the sensor node is possible. Information about the harvestable energy is necessary to design WSNs and EHSs properly. However, detailed information is often not available and special equipment is necessary to measure it. Therefore, this paper presents a simple method to estimate and track the harvestable power. The results can be used offline for design and simulations of nodes or networks, or online for work-load-distribution or energy aware network routing.