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Physicists Promise Wireless Power

StrongGlad writes "The tangle of cables and plugs needed to recharge today's electronic gadgets could soon be a thing of the past. Researchers at MIT have outlined a relatively simple system that could deliver power wirelessly to devices such as laptop computers or MP3 players. In a nutshell, their solution entails installing special 'non-radiative' antennae with identical resonant frequencies on both the power transmitter and the receiving device. Any energy not diverted into a gadget or appliance is simply reabsorbed. The system currently under development is designed to operate at distances of 3 to 5 meters, but the researchers claim that it could be adapted to factory-scale applications, or miniaturized for use in the 'microscopic world.'"

8 of 411 comments (clear)

  1. Discovered???!??!?? by Anonymous Coward · · Score: 4, Informative

    Umm..

    hello.. Tesla??

    ever hear of that guy??

    yea.. he proposed this well.. 100 years ago..

    incidently.. the security word in the image.. photon.. how appropriate..

    1. Re:Discovered???!??!?? by Mr+Pippin · · Score: 4, Informative

      We might ALL know more of Tesla had JP Morgan not stopped his funding. Then again, Tesla had no problem with people getting power for free; which clearly caused issues for Morgan.

      He was also chiefly responsible for the adoption of AC power. Edison was a very strong proponent of DC power distribution, and attacked any advocates of AC power distribution. AC won out for very practical reasons. (power conversion was mostly just a transformer)

      Other than significant infrastructure cost, it's a pity that 3-phase power only enjoys success in commercial settings. It's much easier to make motors and other electricial appliance implementations with 3-phase power.

      Yes, we owe a lot to Mr. Tesla.

  2. Re:Loss by jimstapleton · · Score: 5, Informative

    Actually, the ironic thing is, if this is using Tesla's principles, it's extremely efficient. Maybe not as much as copper wire, but still rather higher than would be expected.

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  3. Re:Tesla ALREADY did it 100 years ago ? so ? by MindStalker · · Score: 4, Informative

    This is using frequency resonation, Tesla's system didn't.

    Think about it this way.

    Lets use sound.. Lets say I make a crystal that vibrates at an exact sound frequency, I can make that frequency sound causing no harm to anyone but that crystal, which will vibrate, and potentially break with intense exposure to the sound. Now of course making a sound intense enough to to shatter the crystal and at the same time cause no harm to ones ears is difficult but its possible.

    Now do this with electromagnetic waves. The real trick is figuring out how not to waste energy pumping it out in all directions. But its about as dangerous as me sitting here 1000 feet from a major radio broadcast station.....

  4. 6.4Mhz - Oh Dear. by MrSteveSD · · Score: 4, Informative

    This thing is supposed to transmit at 6.4MHz. Searching for 6.4Mhz on Google brings back many many links about devices for which that frequency is important. And we wouldn't just be talking about a little bit of radio interference. This would be high power interference.

  5. Re:Am I missing the point here... by Apocalypse111 · · Score: 5, Informative

    Even cell phones are proved to cause cancer...

    No, they're not. Cellular phones don't emit ionizing radiation, all their communications happen in the microwave band. This is not powerful enough to cause cell damage on its own. The thermal effects raise cell temperature a fraction of a degree on the surface of the head (an order of magnitude less than the change experienced by standing in sunlight), and the non-thermal effects show no rigorous evidence of genetic damage. Now, near a base station, the situation is a little different, but don't try to scare John Q. Citizen with unfounded FUD about cellular phones causing cancer.

    More info here.

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  6. RTFA??!?!? by EComni · · Score: 5, Informative
    Maybe the summary got edited to take out the word "discovered", but too many people are chiming in with "Tesla did it!". From the article itself:
    ...
    US researchers have outlined a relatively simple system that could deliver power to devices such as laptop computers or MP3 players without wires.
    The concept exploits century-old physics and could work over distances of many metres, the researchers said.
    ...
    Old technology
    The team from MIT is not the first group to suggest wire-less energy transfer.
    Nineteenth-century physicist and engineer Nikola Tesla experimented with long-range wire-less energy transfer, but his most ambitious attempt - the 29m high aerial known as Wardenclyffe Tower, in New York - failed when he ran out of money.
    Yes. Tesla did it. We know it. The article knows it and states it plainly. The credit has been given. So can we discuss the actual feasibility for short distances, now?
  7. Re:That would be really cool to see... by smellsofbikes · · Score: 5, Informative

    Ummm ... I don't know if you're really unaware of physics here, but if you stick a mouse in a microwave and turn the power to 11, the mouse sort of dies.

    The absorption frequencies of DNA might not specifically match cellphone radiative frequencies, but high-power microwave radiation absolutely is dangerous to living tissue. Water absorbs very nicely at most microwave frequencies, and thermally-induced damage to water-containing tissues means the cell has to repair the damage. The thermal damage may be to the DNA, and it may be just to random proteins in the cell, but either way the cell has to start translating/transcribing, and when DNA is unravelled and depaired for transcription, there's a much greater chance of damage to the DNA happening from random processes, free radicals, stuff like that.

    The question is: does sufficient damage happen to living tissue from radiation at the frequency and power density seen in cellphones, and I don't think anyone has positively answered that question yet.

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