International Journal on Emerging Technologies
Wireless Sensor Networks (WSNs) having large number of sensor nodes which will cover the earth in time to come. Sensor networks covering vast areas are already in the wild and are instrumental in ways not possible using preexisting technology. The most important resource on these nodes is the energy supply and in almost all the cases a battery in the node is responsible for supplying energy for the entire lifetime of the node. The deployment of nodes could be at inaccessible locations and hence once the battery has drained the node is unusable for the network.