When the earth moves - free electricity

Stuart Corner
Tuesday, 03 June 2008 02:35

Business IT - Technology

Australian 'supercapacitor' manufacturer Cap-XX has teamed up with UK based Perpetuum which makes a 'vibration energy-harvesting micro-generator' to develop remote wireless sensing devices that operate without any external power source.

Plants and refineries monitor pumps, machines and processes to ensure optimum safety, up-time and efficiency. This means that maintenance engineers have to walk around to collect data, or use battery-powered wireless sensors which transmit the data to a remote monitoring system. Batteries may survive only two to five years in such harsh environments, so in plants with thousands of battery-powered wireless sensors, the cost of replacing and disposing of batteries is significant.

Perpetuum's PMG17 microgenerator converts mechanical vibration present in all such installations into very low power electrical energy (between 0.5mW and 50mW). However this is sufficient to charge a supercapacitor which is able to deliver the peak power needed to transmit sensor condition data over wireless networks such as Zigbee or WiFi.

"The micro-generator and supercapacitor combination eliminates battery reliability issues and time-consuming maintenance, while enabling significant savings in operational costs and energy use," said Dr Stephen Roberts, technical manager for Perpetuum."

The technology is being trialled at the Nyhamna gas plant in Norway. According to Cap-XX and Perpetuum it is operating faultlessly despite a wide range of temperatures. The sensors monitor the condition of rotating equipment - the main culprit in production shutdowns - and report temperature and overall vibration every five minutes.

CAP-XX and Perpetuum will present a joint paper on the technology at the Darnell nanoPower forum , / June 2 – 4 in Irvine, California.

Supercapacitors also find application in cellphones   where they can significantly improve performance - particularly flash for cameraphones and audio quality - and Cap-XX recently signed a partnership with Japanese manufacturer Murata that it said would boost the implementation of this technology in future handsets, and the development of the next generation of supercapacitors. It announced this week the signing of a formal contract cementing this relationship.