Along the road that leads to wireless electricity, or "witricity" there is an important new travel companion: a circuit developed by Duke University researchers capable of capturing energy from sound and wifi signal with an efficiency close to that of solar cells.
This is a small device that uses 5 copper and glass fiber conductors connected in a circuit through 5 channels made with a metamaterial. The circuit 'captures' energy from the aforementioned sources by converting it into 7.3V electricity (to get an idea, consider that the charging cables of mobile phones provide 5V energy).
"We work to achieve the highest possible efficiency," says Allen Hawkes, one of the project managers. “The properties of the metamaterials do not allow them to be exploited with the design of current antennas. Inserting the power of the metamaterials into a cell phone would allow us to keep it charged simply by bringing it to an area covered by the Wifi signal, and in the future simply to an area covered by the telephone signal ".
In other words, cell phones that never drain the battery.
The research is published in detail in the journal Applied Physics Letters.