Innovations hint at a battery-free future

December’s proven to be a boon for cleantech geeks: earlier this month, we learned about the possibility of mobile devices powered by nothing but voice energy, and now comes news that engineers are working to build an energy-harvesting radio that never needs a battery change.

Engineers at Kansas State University are working with Peregrine Semiconductor to develop a radio that generates and stores all the power it needs by harvesting external sources of energy. Such a device, if made commercially viable, could provide great advantages for such tasks as structural stress monitoring, pressure sensing on bridges and other applications.

Currently, such monitoring radios rely on battery power, making maintenance a tremendous hassle.

“This type of radio technology may exist in your house, for instance, if you have a temperature sensor outside that radios data to a display inside,” said Bill Kuhn, a professor of electrical and computer engineering. “But those devices need to have their batteries changed. This radio doesn’t.”

A prototype device built by master’s student Xiaohu Zhang currently taps into solar energy using small PV cells from hand-held calculators. However, Kuhn said other sources of energy — including thermal, electrochemical or mechanical –could also be used to power the radio.

The Kansas State team plans to discuss their research at a symposium next month. As to when such an energy-harvesting radio will be available on the market? Well, don’t toss your spare batteries just yet.