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What is the Future of Wireless Power?
mfbatzap writes "According to Firdooze, we have seen various devices that can free ourselves from wires at CES 2008. The manufactures, Wildcharge, Powercast and Fulton Innovation, came out with two different methods of transmitting power from source to the devices. Wildcharge and Fulton banked on magnetic coupling while Powercast decided to go with RF (Radio Frequency). So which technology will eventually prevail to be the future of wireless power? Or will the technological setbacks from transferring power wirelessly make it unrealistic to accomplish a wire-free world?"
I'm relatively pessimistic about both of the technologies mentioned due to the inherent limitations that they pose (large leakage of radiated power or short range). I'm looking forward to seeing products based on the wireless power idea that came out of the Joannopoulos group at MIT in 2006.
The idea was that you can setup an RF wireless power transmitter in such a way that it does not actually transmit any power unless it resonantly couples to a precisely shaped receiver. This way there is little to no leakage and they claimed that the power transfer was quite efficient. I'm sure this was posted to slashdot, but I can't seem to find it. Here's a link to the paper if you are somewhere with access to Science: Science 6 July 2007: Vol. 317. no. 5834, pp. 83 - 86 and here's a link to the press release by the MIT news office (no subscriptions required).