Wireless device converts 'lost' energy into electric power
Nov 07, 2013


This five-cell metamaterial array developed at Duke University has a power-harvesting efficiency of 36.8 percen -- comparable to a solar cell. Credit: Duke University

Using inexpensive materials configured and tuned to capture microwave signals, researchers at Duke University's Pratt School of Engineering have designed a power-harvesting device with efficiency similar to that of modern solar panels.

The device wirelessly converts the microwave signal to direct current voltage capable of recharging a cell phone battery or other small electronic device, according to a report appearing in the journal Applied Physics Letters in December 2013. (It is now available online.)

It operates on a similar principle to solar panels, which convert light energy into electrical current. But this versatile energy harvester could be tuned to harvest the signal from other energy sources, including satellite signals, sound signals or Wi-Fi signals, the researchers say.

The key to the power harvester lies in its application of metamaterials, engineered structures that can capture various forms of wave energy and tune them for useful applications.

Undergraduate engineering student Allen Hawkes, working with graduate student Alexander Katko and lead investigator Steven Cummer, professor of electrical and computer engineering, designed an electrical circuit capable of harvesting microwaves.
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Read more at: http://phys.org/news/2013-11-wireless-de...ectric.html#jCp

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http://www.dailymail.co.uk/news/article-...like-Wi-Fi.html