Physics promises wireless power (BBC) [View All]

[eppur_se_muova]

By Jonathan Fildes
Science and technology reporter, BBC News

US researchers have outlined a relatively simple system that could deliver power to devices such as laptop computers or MP3 players without wires.
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Although the team has not built and tested a system, computer models and mathematics suggest it will work.
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To overcome this problem, the team investigated a special class of "non-radiative" objects with so-called "long-lived resonances".

When energy is applied to these objects it remains bound to them, rather than escaping to space. "Tails" of energy, which can be many metres long, flicker over the surface.

"If you bring another resonant object with the same frequency close enough to these tails then it turns out that the energy can tunnel from one object to another," said Professor Soljacic.

1) Power from mains to antenna, which is made of copper
2) Antenna resonates at a frequency of 6.4Mhz, emitting electromagnetic waves
3) 'Tails' of energy from antenna 'tunnel' up to 5m (16.4ft)
4) Electricity picked up by laptop's antenna, which must also be resonating at 6.4Mhz. Energy used to re-charge device
5) Energy not transferred to laptop re-absorbed by source antenna. People/other objects not affected as not resonating at 6.4Mhz

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more: http://news.bbc.co.uk/2/hi/technology/6129460.stm