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Comments: 124 +-   Wireless Power Demonstrated on Friday July 24, @04:10PM

Posted by kdawson on Friday July 24, @04:10PM
from the spooky-action-at-a-distance dept.
power
technology
Necroloth and other readers sent in the story of Witricity's latest demo at the TED Global conference in Oxford, UK. The company is developing a system that can deliver power to devices without the need for wires. The idea is not new — electrical pioneers Thomas Edison and Nicola Tesla assumed that power would be delivered wirelessly. The BBC quotes the inventor behind Witricity's tech as saying that Tesla and Edison "...couldn't imagine dragging this vast infrastructure of metallic wires across every continent." eWeek Europe notes some hurdles the technology must overcome: "The 2007 experiment it is based on had an efficiency of only around 45 percent, but [Witricity's CEO] promised power delivered wirelessly would start out 15 percent more expensive than wires, and improve on that." Intel has also demonstrated wireless charging.
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Submission: Wireless Power Shown by Necroloth (1512791)
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    • Only if the person you're aiming at happens to have hooked the correct resonant antenna into their muscles.

      • Re: (Score:3, Interesting)

        by powerlord (28156)

        Okay ... so what about a taser that works by firing the "head" of the taser but without the trailing wires.

        Heck, if that sort of approach worked (a huge "if" personally), the next obvious steps would be to miniaturize the "heads", perhaps make them burn out after a single use (cheap materials, built in resistor that burns out as the current crosses it) ... ... then pack a few of them into a magazine and we've created a rather nice "Assault Weapon" when you're trying to keep casualties to a minimum and are o

        • If I were a conspiracy theorist, I'd say the government would start feeding our babies pills to subtly alter their bone structure or do unnecessary surgery to add in antenna to resonate with secret government wireless tasers.

          But that's just wonky because of the logistics of the plan.

          Call it a immunization shot and require it for doing pretty much anything, and none the wiser.

  • Standard interface? (Score:4, Insightful)

    by elwinc (663074) on Friday July 24, @04:16PM (#28812961)
    Resonant transfer is great stuff, but what we need even more is a standard interface so that all our rechargable devices can recharge at the same source.

    • Thinkgeek has sold wireless extension cords for a long time [thinkgeek.com]. I wonder if Witricity has solved the issue about domestic cats getting in between the source and destination...

      • Re:Standard interface? (Score:4, Insightful)

        by dgatwood (11270) on Friday July 24, @05:35PM (#28813995) Journal

        I think that's massive overkill. Just provide a 12V rail, a 5V rail, and a ground using a polarized plug. Heck, you can probably dispense with the 12V rail. A 5V rail by itself should cover the vast majority of portable electronics these days. Amperage negotiation? Build the supply so that if it is under too much load, it sheds power connections, then periodically switches which jacks are shed. That's much cheaper to design, and it doesn't unnecessarily add to the complexity of the devices that use it.

          • Re: (Score:3, Insightful)

            by vivian (156520)

            DC to DC regulators are very cheap, for low power needs - which is what you are talking about for most small devices that use wall warts.

            Here's a bunch of devices, with datasheets & prices.
            ahref=http://www.semiconductorstore.com/pages/asp/category.asp?id=56rel=url2html-27418 [slashdot.org]http://www.semiconductorstore.com/pages/asp/category.asp?id=56>
            They start at about $1 and go all the way up to 3.86 for a device that can do dual power rails of exactly that spec - 5v to 3.3v.

            Of course, if you don't care quite as

      • This is only a good idea if the standard included a communication bus and spec for voltage, polarity, and amperage negotiation.

        That's electricity. All that matters here is frequency and amplitude. It'll be up to the receiving device itself to manage voltage and polarity. Amperage is a matter of the transmitter having a sufficient amplitude at its particular frequency, nothing more (power = amps x volts).

  • Thomas Edison ??? (Score:4, Insightful)

    by nurb432 (527695) on Friday July 24, @04:17PM (#28812967) Homepage Journal

    Electrical pioneer my ass, he just got lucky once and was able to afford to hire good talent ( like Nikola ). But i totally agree that Tesla proved it was possible ( and WAS a pioneer ). But he also proved that it takes more then tech to make such a project work, it also needs funding. As brilliant as he was, a businessman he wasn't, and we were set decades behind on projects such as this.

    • Edison has gotten far more coverage in the history books (at least US ones), He was probably best at business, although he is known as an inventor. On the other hand, Tesla was, without a doubt, the greatest engineer that has ever lived. He is proof that a formal advanced education is not necessary for scientific greatness. It is too bad that most people don't realize the impact he truly had.

      • ya, i should give Edison credit for his business savvy.

        Just was irritated to see his name in the same sentence as Tesla in this context and went off on a mini-rant.

    • Re: (Score:3, Interesting)

      by lawnboy5-O (772026)
      My grandmother worked for Thomas Edison - so I the FUD on Edison I can speak to directly as she was my intellectual mentor growing up - and yes we spent hours and hours talking about that crazy Edison.

      Some points you should know:
      Most of the consumer devices you use today are direct descendants of Edison's inventions.
      Edison was no Crook either - even if only paying my sweet grandmother ~17 cents a day around the 1920's.
      He was indeed eccentric toward the later years of his life however, and experienc

      • Most of the consumer devices you use today are direct descendants of Edison's inventions.

        They were 'his inventions' only because his employees created them. So i guess technically you are correct, but that is stretching intellectual honesty. Sort of like saying Bell Labs invented the silicon transistor, when it was actually employees of the labs that did..

        . ...and by the way - it was Marconi that invented most of what was later attributed to Tesla... and returned to Marconi only recently by world courts.

        I call BS. And even if its true they gave them back, Marconi used Telsa's work to achieve it, AFTER Tesla did, so Tesla earned the credit and should retain it.

      • Re: (Score:2, Insightful)

        by kliklik (322798)

        ...and by the way - it was Marconi that invented most of what was later attributed to Tesla... and returned to Marconi only recently by world courts.

        Actually, it's the other way around. Check [wikipedia.org] your [tfcbooks.com] facts [wikipedia.org].

    • Re:Thomas Edison ??? (Score:4, Funny)

      by Heed00 (1473203) on Friday July 24, @05:29PM (#28813923)
      Bah. He came up with that cool electric hammer that was recently discovered as well as the extra hinged legs on chairs to stop you falling over if you lean back too far.

    • Re: (Score:3, Informative)

      by westlake (615356)

      Electrical pioneer my ass, he just got lucky once and was able to afford to hire good talent

      Luck favors the prepared.

      1869 Stock ticker

      1874 Quadruplex telegraph [wikipedia.org] [Polar modulation]
      Rights sold to Western Union for $10,000. [about $170,000 in 2005 dollars Historical Value of U.S. Dollar [mykindred.com]]

      Menlo Park was in the business of invention. That in itself was a new idea.

      1877 Phonograph

      The most interesting thing about the phonograph is that no one saw it coming.

      1880 Incandescent lamp.

      Edison needed a lamp which could be w

      • Edison was very much a crook. How it is exactly that Tesla ended up being labeled some sort of lunatic while Edison is considered some sort of modern Renaissance Man is quite beyond me.

        • It's called politics. Edison new how to work the crowd, Tesla was a lunatic mad scientist. Edison new how to play the game of marketing, tesla annoyed his own followers. Edison was the Bill Gates of his day. an acceptable scientist, but a really good marketer. Tesla is like RMS. a mad scientist.

            • Except perhaps that Stallman was pretty much always right in predicting abuses of software licenses..... The man may be difficult to cope with, but he most certainly is a visionary. That's where the analogy with Tesla is quite fitting.

        • The same way psychopaths on the dole get named "captains of industry" while people who actually work their asses off every day barely make enough to live on.

        • How? More or less the same way that VHS became the standard for consumer video recording over Beta: Marketing.

  • Tesla and Edison predicted it... (Score:3, Interesting)

    by roc97007 (608802) on Friday July 24, @04:18PM (#28812987) Journal

    ...but as geeks we should remember that Heinlein cautioned against it.

    • Are you talking about "Blowups Happen" or "Magic Inc."?

      • No, Waldo. "Blowups Happen" was a (premature, somewhat unwarranted) cautionary tale about nuclear power. Magic Inc could be a cautionary tale about... lessee... nationalized health care. Yeah, that works for me. But Waldo (usually bundled with Magic Inc) was (at it's core) about human physical deterioration brought on by widespread broadcast power.

        • Well, we haven't listened to Gibson about the "black shakes" caused by too much RF - heck we put RF gear near our heads daily.
          Why would we stop now when we can charge it while wearing it? (cancer? naaaaaaah)

        • That's right, it's been decades since I've read them. Time to dig in the book pile again.

          Thanks.

    • Heinlein also wrote about a character that was effectively immortal. Banged his daughters, his sisters, his clones, went back in time and banged his mom and his dad, gave his best friend a sex change so he could bang it, got the AI running a planet and the AI running his ship bodies cloned from him (so he could bang them) and really pretty much humped everything that moved, while being a bigger bad ass than the illicit love child of Dirty Harry, Chuck Norris, and Vin Disel.

      A good wordsmith, but not exactly

  • Mmmm; I'm under the impression that the problem with contact-free power is a significant loss in efficiency. So, if I have to use 25% more power (for example) to charge all my devices just so I don't need to connect a wire, that sounds like a great way to make stuff cost more due to increased electricity demand.

    If I were building power plants, of course, this would sound like fantastic news.

  • Edison? (Score:3)

    by Corson (746347) on Friday July 24, @04:20PM (#28813021)
    I don't know about Edison but Tesla certainly carried out experiments proving that wireless energy transfer is possible.

    • Re: (Score:3, Informative)

      by n3umh (876572)
      It's not only possible, but really damn easy to do.

      You can build a reasonably efficient resonant power transfer doohickey in your backyard out of some copper tubing, some low loss tuning capacitors, a RF power generator, and some diodes and filter caps on the far end to turn the received RF into DC.

      I've built one to couple 4MHz pulses across to a rotating experiment for ultrasound measurement: http://n3ox.net/files/us_ring.jpg [n3ox.net]

      You couple 'em that tightly, and they're like 99% efficient at transferr

      • Re: (Score:2, Interesting)

        by Ryvar (122400)

        But even with Tesla aside, this isn't new... it's just not as vastly useful as people re-discovering it seem to think it is. It doesn't work over gigantic distances, only moderate ones, and there's no engineering you can do to get around that.

        The misunderstanding a lot of people have is that they think Tesla was chasing *truly* wireless power - when in fact this was probably never his goal. Tesla was always chasing after something he called "longitudinal waves" in an attempt to perform worldwide "wireless"

  • Retarded. (Score:5, Insightful)

    by girlintraining (1395911) on Friday July 24, @04:27PM (#28813121)

    Blasting large amounts of EMI solely to avoid the need to put a battery in something is stupid. Right now EM radiation is controlled to the lowest levels it can practically be in order to achieve some transfer of information between two or more points. Any power transfer system is going to muck up what's already in the air. It's called Shannon's Law -- and no matter how you sex up the technology, the fact is you're raising the noise floor doing this.

    Bad engineer. No cookie for you.

    • For Powercast's technology, here's the spreadsheet that can be used to calculate transmission efficiency given distance, frequency, etc.
      http://powercastco.com/wireless-power-calculator.xls [powercastco.com]
    • Hear, hear!
      We'll have practical flying cars before we have practical wireless electricity. Hell, we'll probably have over-unity energy before we have practical wireless electricity!

    • How is that any different than Ethernet over Power?
       
      (I'm not an engineer, someone please explain)

      • Ethernet over powerlines noises up the powerlines, but won't add much EM interference to your wireless, e.g.. I believe the GP is saying that wireless energy transmission is going to make any wireless communication have to compete with the noise, going from a hiss to a yell, like the 2.4Ghz noise of millions of microwave ovens suddenly turning on while you're reading this on your iphone's wifi.

        In practicality, that means your phone batteries will die much faster as it has to pump out 1 bar worth of power i

    • Not that you'd learn it from this non-technical news report, but the energy transfer in WiTricity is non-radiative for this and other reasons. Indiscriminately radiating power not only will interfere with other devices (and violate FCC regulations), but also wastes power by dumping it into the environment, not to mention that people tend to dislike the idea that power is being dumped into their brains. See my other post below.
  • Here's a company that's had wireless power tech since 2007:
    http://www.powercastco.com/ [powercastco.com]
    They even won a best of CES 2007 award from CNET:
    http://reviews.cnet.com/8301-12760_7-9673092-5.html [cnet.com]
    They released working wirelessly powered Christmas tree lights in December 2007 as a consumer product!
    http://news.cnet.com/8301-17938_105-9793204-1.html [cnet.com]
    So this type of wireless power tech has been available in consumer products since 2007 and it appears that there has not been a lot of interest. I am really mystified as why nobody cares. Is it because they mistake this technology for some other kind of well known technology? I can't figure out the psychology here.
    • There are several very different schemes currently being explored for wireless power transfer, with different strengths and weaknesses.
      • Radiative transfer: send a directed beam of energy from a source to a receiver. The advantage is that this can work over long distances, the disadvantage is that you need to either have fixed locations or some active tracking system to keep pointing at the receiver as it moves around, and you need some kind of automated kill switch to make sure you don't accidentally fry anything that walks between the transmitter and receiver or waste power when the receiver is not there. It looks like PowerCast [powercastco.com] and PowerBeam [powerbeaminc.com] fall into this category.
      • Traditional inductive, non-radiative power transfer. This works well, and does not transfer power when the receiver is absent, but is extremely short-range if you want any kind of efficiency; typically, the device to be charged must be sitting directly on or adjacent to the charger. The Wireless Power Consortium [wirelesspo...ortium.com] is pursuing this kind of approach.
      • Resonant, non-radiative power transfer. This relies on the source and receiver being electrical resonators at the same frequency, so that they preferentially transfer energy to one another rather than to other objects in the environment via resonant coupling. This is the approach being pursued by WiTricity [witricity.com], where they additionally rely on resonators that couple primarily via magnetic fields (the electric-field energy is mostly in capacitors inside the devices), which have the advantage that most materials are non-magnetic at these frequencies so the power source dissipates very little energy into extraneous objects (or people). (In contrast, Tesla coils produce strong electric fields external to the device, which interact much more strongly with matter; it's no coincidence that Tesla coils are used as lightning generators.) This operates efficiently at mid-range distances although not as far as radiative transfer (meters at most), does not transfer or dissipate power when the receiver is absent, and is not directional so does not require active "pointing" of the power at the receiver. But it is more complicated than the short-range non-resonant inductive transfer, and requires careful impedance-matching of the source and receiver.

      Full disclosure: I know Prof. Soljacic at MIT, who founded WiTricity, although I personally have no financial interest in the company; all of the above information is public and published, however.

    • So this type of wireless power tech has been available in consumer products since 2007 and it appears that there has not been a lot of interest. I am really mystified as why nobody cares. Is it because they mistake this technology for some other kind of well known technology? I can't figure out the psychology here.

      I'm going to place a guess that it involves price, and possibly obscurity.

      Admittedly, I am just going by the $400 pricetag on that tree from 2007, but most people that would be preparing and setting up a christmas tree today, have been doing so for awhile already and in most all cases don't see a drawback to the wires. They have wired things up before, so the process is pretty well understood and worked around.

      Now, as a geek I would love to have these, but for me it would be specifically for the reason tha

  • I'd like to be the first to complain that resonant power transfer has nothing to do with quantum entanglement.

    You'll be getting a memo from the Tesla Death Ray department shortly; Not observing it won't save you.
  • Tesla actually demonstrated it. He just never got the chance to scale it up. So.. before going around and saying that this has just been invented, go check Tesla's patents.
  • Does it cause cancer yet? If it doesn't, it will because somebody will figure out some way to claim it happens.

  • ... at least in good weather during the day.

  • A company I visited as an FAE back as far (actually is it far?) as 2003 (Splashpower, Cambridge, UK) demonstrated a pad that with specially adapted battery packs would recharge any handheld electronics placed upon it, without wires. I know they didn't survive. I wonder what happened to them, anyone know? I do remember their chief engineer was one of the Atari Jaguar 2 designers, so he must have been fairly used to canned projects.. Yes that's right, the Jaguar 2!

  • Meh. (Score:2, Interesting)

    by djMouton (267156)

    To quote John Dvorak: "My toothbrush has been doing this for years."

    (ducks)

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