A unique method has been developed to scavenge solar energy from monocrystalline solar cells to power wireless router nodes that are used in indoor applications. This method eliminates the need to use alkaline batteries that require frequent replacement from time to time. The system consists of two key components viz. an energy harvesting unit and an energy storage module. The energy harvesting module consists of an adequate number of solar cells connected in seriesparallel combination to scavenge energy from overhead 34 W fluorescent lights that are always operational in office and hospital hallways. A set of ultracapacitors were used as the energy storage device and alkaline batteries were used only as a back-up energy source. The router nodes (Crossbow MICAz motes) controlled the operation of the energy scavenging circuit in order to harvest adequate amounts of energy for optimal performance. In order to minimize power consumption, two router nodes (each with 50 % duty cycle) were ...