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Physicists Promise Wireless Power 411

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.'"
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Physicists Promise Wireless Power

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  • by brennanw ( 5761 ) on Wednesday November 15, 2006 @09:36AM (#16850918) Homepage Journal
    ... and the subsequent and inevitable lawsuits brought about by people convinced that the wireless power technology is giving them cancer would probably get a little tiresome.
    • Re: (Score:3, Interesting)

      by Zigg ( 64962 )

      You don't think there are any safety issues inherent here? I for one was surprised to see no discussion of it at all in the BBC article.

      It well could be safe (or at least as safe as any other tech currently in use) but, man, I'd be looking at it very closely myself if I were responsible for bringing it to market.

      • You have a point. (Score:5, Insightful)

        by brennanw ( 5761 ) on Wednesday November 15, 2006 @09:44AM (#16851016) Homepage Journal
        ... there might be health issues -- but I suspect there will be lawsuits whether there are health issues or not.
      • by TobascoKid ( 82629 ) on Wednesday November 15, 2006 @10:27AM (#16851622) Homepage
        From the BBC Article:

        5) Energy not transferred to laptop re-absorbed by source antenna. People/other objects not affected as not resonating at 6.4Mhz

        That was at the bottom of the graphic. So it should be safe (however, seeing as the technology only exists as a computer model and not as reality, I would bet that if there are any safety issues they will only come to light after such a device is actually built)
        • Isn't that one of the laws of thermodynamics? Not all the energy would be reabsorbed, correct? And that excess, no matter how small ... well, it would be enough for lawyers if not doctors.
          • Re: (Score:3, Informative)

            by 241comp ( 535228 )
            No, the laws of thermodynamics say that 100% of the energy will be absorbed... By the receiving device, by the transmitting device or by something else. But 100% of it will be reabsorbed by something, somewhere (well, unless it gets radiated at such a trajectory that it does not encounter any mass capable of absorbing it). The question is, what part of your body resonates at 6.4Mhz (and do you care if it absorbs energy).
      • by Intron ( 870560 ) on Wednesday November 15, 2006 @10:44AM (#16851866)
        Fortunately there are no health issues with Lithium-ion batteries. I sleep with my laptop.
      • Re: (Score:3, Insightful)

        by neoform ( 551705 )
        Forget Safety, what about efficiency?

        Doesn't anyone else think that this method means a massive waste of electricity during the conversion, not to mention the wasted energy not even using used by the target device?
    • Re: (Score:2, Insightful)

      Please don't assume it's totally harmless and I won't assume it's totally harmful.
      Sure, we're all gonna die, but some precautionary principle could ease the pain.
      • Re: (Score:3, Insightful)

        Do you live somewhere that has radio stations, tv broadcast, or cellular service? Whether or not you do, you'd better freak out. You're being penetrated by electromagnetic radiation all the time! No matter what you do! No matter where you are!
    • Re: (Score:3, Informative)

      Yesterday the Corus radio network across Canada had a guest on with a study that's presumably scientific but I missed the details, and he found that cell phone radiation poses a 2 to 3 times risk of giving the user tumours. He said the problems with initial studies was the assumption that microwaves at so low an intensity as to not HEAT the subject, could not do damage. But in fact, even low intensity waves cause damage according to his study.
      • by phritz ( 623753 ) on Wednesday November 15, 2006 @10:48AM (#16851924)
        Ummm ... I don't know if you're really unaware of the counter-argument here, but this has nothing to do with heating or not. The plain and simple fact is that DNA does not interact with light at microwave/radiowave frequencies. Therefore DNA can't get damaged by cell phone radiation. Therefore, it doesn't give you cancer. I'm still not aware of any non-crackpot scientific studies that show any evidence of tumors being caused by cell phones. If you can come up with a reference to this guy, I'd be happy to take a look, but he sure sounds like a crackpot to me.
        • by smellsofbikes ( 890263 ) on Wednesday November 15, 2006 @12:01PM (#16852956) Journal
          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.
  • Discovered???!??!?? (Score:4, Informative)

    by Anonymous Coward on Wednesday November 15, 2006 @09:36AM (#16850920)

    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..
    • Re: (Score:2, Informative)

      by Ummite ( 195748 )
      Exactly, Tesla did it 100 years ago, and over more than a km distance! But people don't know that guy. Tesla coil, radio transmission, AC electricity etc. The only thing new is the usage, little scale.
      • by q-the-impaler ( 708563 ) on Wednesday November 15, 2006 @10:43AM (#16851852)
        My understanding was that it wasn't pursued because Tesla marketed it as "Free Power" and no company was interested in giving people free anything at that time. Oh, wait, nothing's changed.
      • Re: Tesla (Score:4, Funny)

        by RareButSeriousSideEf ( 968810 ) on Wednesday November 15, 2006 @10:48AM (#16851928) Homepage Journal
        Didn't he do that "Little Suzie" song?
      • Re: (Score:3, Informative)

        by delire ( 809063 )
        True. Sadly his plans for wireless-electricity were completely thwarted, interestingly enough, by a refrigeration company that needed low prices for copper in order to enjoy low-cost production for their cooling systems. The reason copper was cheap, of course, was because wired electricity was in demand at the time.

        More on that in here [].

        Next: An engineer working for Ford will be on the cover of Time magazine hailed as a saint for his invention, the Hydroden Engine. No one will find it conspicuous the a
        • by Rei ( 128717 ) on Wednesday November 15, 2006 @12:47PM (#16853828) Homepage
          Tesla did a lot of great, original work. Sadly, much of his later notions were demonstrably 5 parts fancy to 1 part reality. Heck, even Mythbusters tackled one of Tesla's later proposals (the Earthquake Machine).

          Tesla's method of wireless power falls into the latter. Even if there was a copper conspiracy, it would be a good thing, because it stopped money from being poured into an unworkable design. It was based on countless false claims and pseudoscience (random example: The atmosphere above 5km is so thin that it ceases to be an insulator and instead conducts electricity with almost no losses over long distances) -- most of them simply assumptions, without a hint of scientific backing, let alone a calculation on something so critical as efficiency.

          Why Tesla is treated in a cultlike fashion ("He said it -- it must be true!") by many people around here is beyond me. He invented some great stuff. He also proposed a good bit of pseudoscience. The two are not mutually exclusive, people. In his later years, he was nearly broke, and was desperate for new contracts. He became OCD. He claimed to have completed a unified field theory, yet no notes on it were ever found. He claimed that spacetime wasn't curved, and thought that Einstein was just bedazzling people and keeping them from the truth. He made astounding claims about what his "death ray" could do, without ever doing the math (obviously -- it was basically an ion drive). He started talking about creating a "wall of light" by using a certain pattern to manipulate electromagnetic waves which would allow spacetime and matter to be tweaked at will. He even proposed a device to take pictures of peoples thoughts, which he thought appeared in the retina. He proposed an earthquake machine, and said he could shatter the world if he built a big enough resonator.

          The list goes on.

          • by Sfing_ter ( 99478 )
            Ummm... he actually made one... and caused an earthquake...

            http://www.intuitor.com/resonance/tesla.html [intuitor.com]

            The problem with hiding technology is the telephone/radio/programming issue, where more than one person can come to the same conclusion, albeit via different means/functions/devices.
          • mythbusters (Score:3, Informative)

            by isotope23 ( 210590 )
            Yes, I saw that episode. I also saw that using a VERY small weight (like 5lbs max) they made the entire steel bridge oscillate. I believe Tesla did not specify how long it would take, only that it would do so. So IMO the theory was sound. If run long enough the oscillations should induce metal fatigue causing the bridge to fail. Too bad they don't have a bridge they could try to destroy, I'd like to see them hook up progressively larger weights to see if they could take it down.
    • alexchiu (Score:3, Insightful)

      by Hao Wu ( 652581 )
      This was concepted by powerman Alex Chiu. You are right. It is not new idea of super energy platform.
    • by Mr Pippin ( 659094 ) on Wednesday November 15, 2006 @10:48AM (#16851932)
      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.
      • Re: (Score:3, Informative)

        by ajs318 ( 655362 )

        It's much easier to make motors and other electricial appliance implementations with 3-phase power.

        The 1950s called, they want their words back. Inverters aren't hard to build. Just turn your AC into DC; then have a three-stage phase-shift oscillator with each output driving a power amplifier. There's your 3-phase AC. You can even change the frequency (which gives you motor speed) and the phase ordering (which gives you direction of rotation) electronically.

        DC brushless motors are everywhere nowa

        • by Grishnakh ( 216268 ) on Wednesday November 15, 2006 @02:27PM (#16855714)
          DC brushless motors aren't really DC at all, they're AC. The only reason they're called "DC brushless" is because the motor amplifier is powered with DC, and converts this to waveforms to power the motor. There's two kinds of amplifiers, linear and PWM. Linear amplifiers create true sinusoidal waveforms for driving the motor, while PWM amps, as you might imagine, use PWM in place of sinusoidal waveforms.

          Also, high-quality DC brushless motors/amps use encoders instead of hall-effect sensors because of their greater resolution. HE sensors are usually still used to determine absolute position.

          But back to 3-phase power; yeah, it really doesn't make that much sense for non-industrial applications, because of the extra copper wire you have to run, and the extra complexity. The advent of power electronics has made it unnecessary. Even AC isn't that necessary any more at high power levels: in many places, high-voltage DC (HVDC) transmission lines have been installed instead of AC, because today's sophisticated power electronics are able to convert between AC and HVDC with very high efficiency.
    • RTFA??!?!? (Score:5, Informative)

      by EComni ( 998601 ) on Wednesday November 15, 2006 @11:12AM (#16852228)
      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?
  • by joss ( 1346 ) on Wednesday November 15, 2006 @09:37AM (#16850930) Homepage
    I bet I'm not the only one here who has taken the piss out of someone for asking if they can get a wireless power supply for their laptop
  • Loss (Score:2, Interesting)

    by Nerdfest ( 867930 )
    I can't see avoiding a large degree of power loss, and the last thing we need right now is something more inefficient than wll-warts.

    It would also suck to have a random bdy part resonate in a similar frequency ...
    • Re:Loss (Score:5, Funny)

      by Anonymous Coward on Wednesday November 15, 2006 @09:39AM (#16850962)
      I can't see

      that's why you're not a genius.
    • Re:Loss (Score:5, Informative)

      by jimstapleton ( 999106 ) on Wednesday November 15, 2006 @09:42AM (#16850998) Journal
      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.
    • Re: (Score:2, Funny)

      by Dunbal ( 464142 )
      It would also suck to have a random bdy part resonate in a similar frequency ...

            I dunno, I guess it all depends on exactly WHICH body part we're talking about... this might revolutionize the online pr0n industry :)
    • I can't see avoiding a large degree of power loss, and the last thing we need right now is something more inefficient than wll-warts.

      I would expect that it's worst than that, the wireless power transmitter would be powered with a wall-wart.
    • In local news, an impatient businessman checked his email while waiting on his child's orthodontic work. Seventeen people were injured.
    • Well, I was thinking along similar lines -- it wouldn't seem to offer much if at most, you can power a factory, since a factory can already be easily powered via cords. But then I thought about aircraft (I work in aerospace). Remember that with aircraft, conserving weight is so important, and you basically have "skeletons in the sky". Since you have to send electrical wiring to many parts of the aircraft, that requires you to put holes through the frames (left-right spanning structural members), which we
      • Well, yes, sure, but how can one get through the metal bulkheads with an electromagnetic signal ? Unless your aircraft is made from some type of material that will allow e and b fields to buzz right through it (and if so, perhaps we can sell that material to various Stealth programs, no ?), you're going to have to cut holes for waveguides instead of cable ways.

        The major savings in transmitted power in an aerospace environment would be in weight of wiring. If your transmitter / receiver assembly and waveguid
  • 100 years later... (Score:4, Insightful)

    by Anonymous Coward on Wednesday November 15, 2006 @09:37AM (#16850940)
    Three Cheers for Nikola Tesla!
    • Re: (Score:3, Funny)

      by Rhinobird ( 151521 )
      My what a good excuse for us geeks to go and get a beer!
      Telsa is vindicated! Pass me a beer!
      It's Wednesday! Pass me another beer!
  • Problems (Score:5, Insightful)

    by Solokron ( 198043 ) on Wednesday November 15, 2006 @09:39AM (#16850956) Homepage
    This would bring an entirely new scale of issues. People getting arrested for wireless power theft would be cute.
    • Well, AFAIK people already have been punished for wireless power theft. The power in that case came from a radio transmission tower.
  • by jimstapleton ( 999106 ) on Wednesday November 15, 2006 @09:40AM (#16850970) Journal
    Now I know you haven't seen the rats nest behind my desk, but 3 computers (only one a notebook), a PS2, monitor, KVM, Hub, printer, associated power strips, Nintendo DS plug and MP3 player plug... I assure you, I would not just use this for my laptop and MP3 player. I have way too many wires, and if I could remove a dozen or so of them, it'd help a lot. Add wireless networking to the mix, and wireless speakers, and it just might be manageable again... And yes, I know both of those already exist.
    • Re: (Score:2, Funny)

      by dscx ( 230411 )
      All that hardware, and a rats nest too? You sure keep a busy office...
      • Re: (Score:3, Funny)


        Rats are awsome critters, very friendly and social. I finally got them to stop gnawing on my feet. I even still have three toes left!
  • Great (Score:5, Funny)

    by Frankie_CWRU ( 711904 ) on Wednesday November 15, 2006 @09:44AM (#16851014)
    now the people driving around in vans stealing my wireless don't even have to stop to recharge their laptops.
  • wouldn't this (Score:4, Interesting)

    by Broken scope ( 973885 ) on Wednesday November 15, 2006 @09:44AM (#16851020) Homepage
    be best suited for low power applications. Charging a cell phone or palm pilot for example. I mean, I don't see this working for my 500watt computer or my xbox 360. It might charge the controller for my 360, but it would really only get rid of maybe 2 cables behind my computer.
  • 6.4Mhz - Oh Dear. (Score:5, Informative)

    by MrSteveSD ( 801820 ) on Wednesday November 15, 2006 @09:56AM (#16851160)
    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.
  • tesla promised not only wireless power, but also death ray. could you make sure you deliver that to?



    technology historians for the realization of past promises

    ps: don't think we've forgotten about those rocket cars mr. popular science!
  • The ability to deliver wireless electricity has been known decades. The big problem has been how to determine who uses what. I believe Tesla proposed a huge power generator that could be used to power all the electricity needs of a city wirelessly. His idea was, of course, shot down because no one knew who to charge for what.
    • Re: (Score:3, Interesting)

      by gad_zuki! ( 70830 )
      More like it was (and remains) highly inefficient and would have used a large part of the spectrum. You could have wireless power to your home but you can kiss the cell phone, tv, radio, etc goodbye.

      A great deal of Tesla's achievements are apocryphal. There is no real proof about claims of wireless power to motors miles away and other things people attribute to him. In reality he was a clever guy but not this victim of forward thinking/backwards government as his myth protrays him as.
  • This amazing new "wire-less" technology is the all the rage to-day.
  • by Dasher42 ( 514179 ) on Wednesday November 15, 2006 @10:03AM (#16851246)
    What would happen if these were used on highways to power electric cars? Batteries still only return a tenth of the energy put into charging them, so directly conveying power to automobiles would be interesting indeed.
    • by shmlco ( 594907 )
      I suspect we'd be bankrupt, as tearing up every street, road, and highway in the country to bury the transmitters is going to be a fairly expensive proposition...
      • put caps in the car sufficient to let them go from 'section' to 'section' with the amount of juice provided from the last section enough to get to the next one..

        further, who said it has to be under the roads? but it in the light fixtures overhead,-- hell- put a retransmitter on the front & rear of every car and allow them to pass the juice along in a chain gang..

        the thing about the concept that would scare me is you've saved so much in battery weight, & the cars are much more efficient, they must
    • by Macka ( 9388 )

      Or perhaps trains or trams. Do away with the need to have some part of the train/tram in connection with a live electrical connector and there might be speed, maintenance and possibly noise benefits to future designs. It's certainly an interesting area for research.

    • The electromagnetic radiation being used isn't directed, so it would dissipate very quickly. I expect this would waste a lot of energy over short distances for handheld electronics, but it would be totally infeasible for cars.
    • Batteries still only return a tenth of the energy put into charging them,

      Sorry, this is rubbish. Batteries are generally highly efficient. The efficiency of the system is determined by the charger which can be anything from crap (30%) to excellent (90%).
  • by MrJerryNormandinSir ( 197432 ) on Wednesday November 15, 2006 @10:05AM (#16851268)
    Nothin new hear really. remember Tesla's dream? Free wireless power. The Huge facility at colorado springs did just that.
    The only wireless energy source transmission I've seen so far is with RFID tags. have you ever taken one apart? Chek out the
    antennea.. much like the tesla antennea.
  • April Fools! (Score:4, Informative)

    by RobertNotBob ( 597987 ) on Wednesday November 15, 2006 @10:07AM (#16851286)
    This was one of Think Geek's April Folls jokes earlier this year.


    I guess truth CAN be stranger than fiction.


  • .. or maybe they are just very small batteries ...
  • If this works, we need to define a standard resonance frequency NOW. I, for one, don't need a repeat of the wall wart debacle where every device needs its own charger.
  • by eno2001 ( 527078 ) on Wednesday November 15, 2006 @10:15AM (#16851394) Homepage Journal
    ...welcome our new tumor causing overlords!
  • Microscopic gods.... (Score:5, Interesting)

    by Himring ( 646324 ) on Wednesday November 15, 2006 @10:16AM (#16851420) Homepage Journal
    This sounds so much like one of the first Sci Fi books I ever read in high school called, "Microscopic gods" (or was it "Microcosmic gods"?) -- I think it was. A scientist creates microscopic evolution. He keeps experimenting, forcing "stresses" on the creatures to make them evolve. They eventually become sentient, intelligent, creative. To fund his research he invents wireless power. A congressman hooks up with him and uses subterfuge to wrist the new power invention from him. Meanwhile, his microscopic gods keep evolving until they are more advanced than the scientist himself. They refer to him as their "father" or "god" or something. The congressman sends in the military, using the wireless power, to take over the scientist's lab and even washington I think. The scientist sends a request to his creatures to invent an invulnerable forcefield to withstand the attack. They do so, but make it only big enough to cover their little area. He cannot contact them. They send him a -- for the first time ever -- message humbly asking if the parameters were right since they suspected he could not reach them. They also provide the means for him to communicate back. He tells them to increase the size to cover his island and they do. All the planes using the wireless power to take over the country crash, and senator is fouled and the scientist lives happily ever after in his grey, dome, shelled, island with his little gods. The story ends stating the military continues to use the dome for target practice....

    • Re: (Score:3, Funny)

      by Valdrax ( 32670 )
      As others have mentioned the author and title of the story you're looking for, I'd just like to chip in that, in a similar vein, "Blood Music" by Greg Bear is also quite good. It's about a guy who invents intelligent white blood cells and injects himself with them.
  • And it won't be long before we get a Waldo [wikipedia.org] who can show us all how to get power for free! My Evil Plans will no longer require a gigawatt power source! Bwahaha!
  • I worked with a guy 4 years ago that was developing this. I have seen it work and it is cool. One of his backers asked me what I though it could be used for and I began listing all kinds of stuff at a n office. No need for anything to plug into the wall. It really was cool. Although with his, and the frequency that he was using, you just needed to set your cell phone within 2 feet of the transmitter. Come back a couple of hours later and the phone was charged.

    In all honesty this really is old news. Nicola T [wikipedia.org]
  • Hmmm (Score:3, Funny)

    by Bombula ( 670389 ) on Wednesday November 15, 2006 @11:41AM (#16852650)
    The article mentions resonant frequencies, and I'm suddenly reminded of a certain visor-wearing Starfleet officer always blaming the phase-inducers for some damn thing to do with resonant frequencies...
  • by QuantumFTL ( 197300 ) on Wednesday November 15, 2006 @06:18PM (#16860256)
    Here's the actual paper [arxiv.org] the article is about.

    Seems to me to be little more than a clever way to couple oscillators using higher order moments (that confine the majority of the energy around the device to be very close as they drop off much faster than inverse squared). The paper contains some interesting preturbation methods for determining how badly other objects in the nearby area would affect such a system, however I haven't had time to go through the math in detail.

    Disclaimer: IANAP (but I do have a degree in physics) - any actual physicists like to comment on the mechanism here?

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