Wednesday, 11 June 2008
Energy scavenging sensors
As the widespread deployment of wireless sensor nodes continues towards the eventual ubiquitous sensing fabric of the future, there will be an increasing demand for battery-less methods of powering them. For some technologies, such as traditional passive radio frequency identification (RFID) tags, there is no need to provide power on-board at all. However for other technological solutions, using wireless networks such as Zigbee or WiFi, there will be a need for power without recourse to a battery.
For situations where sensors are located on machinery, there is a more obvious solution. Microgenerators such as Perpetuum's PMG17 are able to convert mechanical vibration into usable electrical energy. If this is combined with a suitable storage technology such as a supercapacitor, it is possible to deliver the peak power required for indefinite regular status reports over wireless networks. For machinery where vibration is a part of normal operation, such power harvesting is an ideal solution.