An Intel boffin has come up with a way to harvest electricity from the
airwaves, and he hopes the technique could be used to power mobile
phones or small gadgets sometime in the future.
By using a TV antenna pointed at a massive TV tower, Intel researcher
Joshua Smith and student Alanson Sample managed to power a small LED
thermometer. It's a good start, but nowhere near enough for any truly
practical use. Obviously there are tons of digital and analogue signals
at various
frequencies, traveling through the air and even our own bodies, but
making any use of what basically amounts to radio pollution isn't
easy.
"That's the thing with these broadcast mechanisms - if you don't
collect the power and do something with it, that energy's just going
to, you know, heat up the grass or something," says Smith. "There's
nothing else that could happen with it."
Smith hopes that the technology could be used to provide mobile devices
with extra power sometime in the future, allowing them to remain on
standby indefinitely. It will probably never produce enough power to
forgo chargers and batteries, but every little helps.
One of the more interesting ways of using the technology would be to
create wireless keyboards, mice and gamepads, and Smith believes that
in a couple of years we could see a truly wireless mouse or Wii
controller, powered by Oprah.
Nokia is also trying to harvest power emitted by cell towers, as well
as TV towers and other transmitters, and MIT used a similar approach to
light a light bulb in 2006.
More
here.