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BOB HIRSHON (host):
Electricity, without the wires. I’m Bob Hirshon and this is Science Update.
Wireless devices like cellphones and laptops are only wireless until their batteries run down, and they have to plugged in and charged. But now researchers at MIT have demonstrated a technology that would allow devices to be charged by wireless electricity, or "WiTricity." It uses a pair of magnetically coupled coils—one is plugged into a wall and generates a magnetic field of a certain frequency; the coil in the receiving device is tuned to that frequency. If the wireless device is anywhere in the room it picks up the electricity and charges automatically.
In other energy news, scientists at the University of Utah have developed small devices that turn heat into sound, and then sound into electricity. The devices could convert excess heat from power stations, factories, or even the circuits in computers into useful electricity. I’m Bob Hirshon, for AAAS, the science society.