

The Ghost of Tesla: MIT researchers demonstrate wireless electrical power transfer  - nickb
http://web.mit.edu/newsoffice/2007/wireless-0607.html

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sosuke
Not to downplay the accomplishment but I was fairly surprised that the article
represented the idea as entirely unique without ever actually mentioning
Tesla.

"WiTricity is rooted in such well-known laws of physics that it makes one
wonder why no one thought of it before."

~~~
DaniFong
The concept of sending electricity wirelessly has been imagined, but nobody
had come up with a decent way to avoid the losses except by using an actively
controlled beam method. It's pretty darned innovative.

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mynameishere
Snore. Basic fact checking 101 (for MIT!):

<http://www.google.com/search?q=microwave+power+transfer>

<http://en.wikipedia.org/wiki/Microwave_power_transmission>

~~~
DaniFong
This is a non-radiative method: in the absence of a receiving device with a
correctly tuned inductance, in the field surrounding the emitter there will be
no, or hardly any E x B field. In other words, there would be no, or hardly
any energy leaving the emitter.

Most interestingly, the method they describe can be used in a unidirectional
manner, and the power supplied would fall off much less quickly than 1/r^2.
One could even put a switch on the receiving circuit. When the circuit is
broken, the total energy expended by the emitter would zip down to zero
passively, without any control required. In fact, it's a fairly
straightforward game to construct one of these on one's own. Too bad I didn't
think of it ;-)

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zandorg
Do they use this in nature?

