back to article Boffins demo wireless electricity

Researchers in the US have demonstrated an experimental wireless energy transfer system that could pave the way for truly wireless computing. The team has already successfully made a 60W light bulb light up from a distance of 2 metres. This might be very early days, but the work has been described as "truly pioneering" by …


This topic is closed for new posts.
  1. jimbarter



  2. Anonymous Coward
    Anonymous Coward

    Not very environmentally friendly

    Nice demo of technology but if it ever becomes widespread then we will be using far less efficient means of power delivery and hence use a lot more power... The example of a 60W light bulb being lit at 40% efficiency means around 150W of power are needed to light it!

  3. Mark Daniels

    Coil, Coil Coil

    This is hardly 'new'. Nicola Tesla did the same thing 150 years ago. Hence the Tesla coil and that excellent White Stripes cameo in Coffee / Cigarettes from four years ago.

    Still, Americans 'invent' everything. After all, Turing was Texan, the Enigma code was cracked in the Bletchley CA and the all american apple pie is German.


  4. JBR


    Cobblers. My leccy toothbrush has been recharged without wires for years on its stand.

    Seriously, could they have timed their announcement any worse with the latest scare about killer mobiles and wireless routers eating babies?

  5. Anonymous Coward
    Anonymous Coward

    didn't Nicola Tesla do this in 1899?

  6. Anonymous Coward
    Anonymous Coward

    Electromagnetic radiation

    Considering the scare-mongering over Wi-Fi networks, can you imagine the impact of this? I'm stocking up on tinfoil hats now.

  7. Anonymous Coward
    Anonymous Coward

    No effect on the body??

    So when all the pigeons come crashing down out of the sky on the wireless power hotspots I think that the view that no effect on the body may change.

    Also how do people think that Magnetic Resonance Imaging works!!!!!! Umm Magnetic field to wobble all your atoms around so that they give off a radiative effect that can be measured!

    Sadly this is a typical science soundbite that is necessary for them to get continued funding!

  8. Skavenger


    Talk about energy wastage. Especially if its left on all day when your at work.

  9. James

    Electric toothbrushes do this - so what's new?

    Electric toothbrushes use this principle to get charged (wireless) - so all that's new here is the scale and separation.

    But just think of the field day (no pun intended) all those panicking about wireless networks will have when they find out about Wireless mains power !!

  10. Anonymous Coward
    Anonymous Coward

    "her LCD screen made her sneeze"

    Perhaps you should look up "photic sneeze" - it affects about 20% of the population. (

    Sensitivity to bright lights varies. I find that a fluroescent tube or sometimes even an ordinary tungsten bulb can trigger it, so I don't think it's far fetched to suggest that somebody particularly sensitive might be affected by staring at a bright LCD screen.

  11. Alastair Dodd

    Yeah been done before

    old idea and practical? I think having 30cm wide copper loops around a lightbulb is practical certainly especially if you lose 60% of the energy...

    OH COME ON! This is pointless and stupid especially considering most people are trying to save money. There are already much better devices coming out for phones, pdas, etc based on this anyway.

  12. Andrew Rose

    40% efficient

    From the BBC article on the same...

    "Measurements showed that the setup could transfer energy with 40% efficiency across the gap."

    They'll need to do a lot better than that in today's "green" age. (I know that some end devices, such as incandescent bulbs, are very inefficient. Even so, we can't afford to throw away another 60% on the path from energy source to energy use.)

  13. Jim Keir


    I can just see them... huge Tesla - sorry, WiTricity - towers, encircled by crowds of deeply confused migratory birds wondering why they're not in Finland yet.

    Still, might be a way of solving the Pigeon Problem in London, just set one of these up with an enormous bug-zapper installed downwind.

  14. Joel

    What, magnets don't work???

    Do you mean to tell me that all the money I spent on magnetic bracelets, insoles, matress covers and belts has been wasted?

    I feel sure that there will be comments about magnetic fields. There is an entire industry based upon the therapeutic effects of magnetism. Since the crystal believers already believe in this stuff, there is no way you can eliminate the furore simply by stating that there is no scientific evidence for magnetism having any effect on the human bodies.

    If they believed what scientists say, they wouldn't have the magnetic bracelets....

    One for Panorama, methinks.....

  15. Anonymous Coward
    Anonymous Coward

    And this is new?

    Just walk under a HT power line with a flourescent tube in your hand and see it light up?

  16. Anonymous Coward
    Anonymous Coward

    How many access points does it take to change a lightbulb?

    Don't know - ask S.I.D.

  17. Mad as a Bat

    ...there you go...

    exposure to anything to do with electricity or magnetism gives you coughs and sneezes

  18. Chris Collins


    I think you'll find this causes cancer in small children and should be banned

  19. Anonymous Coward
    Anonymous Coward

    Ye canna change the laws of physics, Captain!

    "The team adds that it is about a million times more efficient than non-resonance based induction."

    And possibly a million times less efficient than a mains adaptor. And the only reason I have so many adaptors is that every gadget needs a different one.

    Although the fact the many nowadays can be recharged from a USB socket is enforcing standardisation.

    What we really need is a mains adaptor that can charge several USB rechargeable devices simultaneously.

  20. MacroRodent Silver badge

    Old stuff

    Reminds me of a very old (first published in the 1920's, I think) Finnish book for technically minded kids called somethig like "the Book for experimenters and inventors". It had recipes for several fun experiments along those lines involving what the book called "a Tesla transformer." There was also a simple wireless telephone based on induction coils: Wind two 2-meter diameter loops of wire (I don't recall how many windings you need, except I recall I ran out of wire when trying to build one) , hook a telephone microfone and battery to one and a telephone earpiece to other, and talk up to 100 meters distance.

  21. Neil Barnes Silver badge

    Shall we get the Nobel committee ready?

    'MIT explains how resonant coupling can add energy to a system ...'

    They changed the laws of thermodynamics since I were a nipper, then?

  22. Alan Potter

    And who's going to pay your 'leccy bill?

    With WiFi I didn't mind too much if someone used a bit of my bandwidth as long as they didn't take the piss.

    But I'm buggered if I'm going to let someone add costs to my electricity bill - it's expensive enough as it is!

  23. Richard Dawson

    Not all Tesla, all of the time

    I think you Tesla fans are brandishing your clubs of outrage without good cause. It appears that the chaps at MIT are using a rather different mechanism of power transmission than that used by Tesla.

    Just because the great man came up with a way of wirelessly transmitting power doesn't mean that he has dibs on all mechanims for doing this.

  24. Anonymous Coward
    Anonymous Coward

    just a note

    'So when all the pigeons come crashing down out of the sky on the wireless power hotspots I think that the view that no effect on the body may change.'

    Pidgeons have eyes. They only used magnetic fields for long distance navigation. I don't think there will be a 'Core' like barage of missile pidgeons hitting skyscrapers all of a sudden after flying through a teslectric field...

  25. Stephen Tompsett

    Research Grant?

    Do you think it's worth applying for a grant to research a 99.99% efficient method of getting power to a lightbulb, using a pair of metallic conductors?

  26. Mike Silver badge

    Collateral Damage to Pigeons

    Tesla would have never allowed it. There was a man who _really_ loved pigeons, or, at least, some of them.

  27. dodge

    sounds quite hard, actually

    Take a Tesla coil and measure the electric field around it.

    Now the MIT bunch say that there is almost no electric field on their contraption (and magnetic and electric field are highly linked usually -- hands up the Right Hand Rule), and on their device even the magnetic field is constrained unless it is energising another coil. This is more like high frequency antenna/wave guide design than a couple of loops of copper.

    I'd imagine one of those fluorescent "low energy" lightbulbs would make it go bananas, though.

    And the point about the sheer numbers of crystal believers and magnet healers is very true. I suspect the MIT guys don't hang around many wholistic healing neighbourhood markets.

  28. Terrence Stffer

    You bastards

    You are damned bastards, you'll cause additional eletromagnetic pollution and hazards.

    N. Tesla was always sick for its continuous experiments with magnetic fields, he had a deficit in immuno systems and he can't suffer the contact of common objects and foods. All this because his body was always exposed to magnetic fields.

    Now you want to use magnetic fields for transmitting electric power: you should be cooked in a microwave slowly, you bastards, together with all your companions.

  29. Chris

    MAGNETIC field to recharge a laptop?!?

    I can't believe no one has mentioned this yet. According to this article, the wireless power transfer uses a MAGNETIC FIELD to transfer the power. The researcher may be correct in saying that magnetic fields have not been shown to have an effect on the human body. But magnetic fields sure as hell do have a very noticeable effect on electronics. Go ahead, recharge your laptop's battery using that magnetic-field wireless power transfer. Just don't expect your hard drive to contain anything meaningful afterwards. Oh, and be sure to keep any CRT monitors or televisions far away as well.

  30. Michael Martin

    RE: MAGNETIC field to recharge a laptop?!?

    Ooooh yeah... There's a very good reason I set my CRT monitor to have a refresh rate of at least 75Hz. It gives me a headache to watch that obnoxious flicker that only becomes more pronounced in my peripheral vision. Just imagine having a constant 60Hz wobble on the screen.

    In regards to the hard drive though, I suspect the magnetic field is not as strong as you think. The entire reason it affects the pickup coil is because it's at just the right size for the frequency of the power signal to get picked up. So though it may decrease the overall life expectancy of any data on a drive due to the constant low-grade magnetic fluctuation, it will not immediately wipe it clean. The platters aren't conductive, and even if they were, they wouldn't be the right size to pick up on the signal as effectively as the pickup coil.

  31. Jim


    So you have an electric toothbrush that recharges wirelessly. This is via induction, re-read the article.

    The article also seems to have neglected to emphasise that one of the charcteristics of resonant-coupled circuits is that there are very little stray fields produced, that is how a high(ish) efficiency is achieved compared to inductive transfer.

    I don't know about other people but I don't consider having to cart around a 2ft diameter coil as being particularly convenient...

    Lastly, I think this is the first scientist I have heard that categorically states that it is only the electrical bit of microwaves that cooks the chicken, or maybe they just forgot what the M in EM radiation means...

  32. Mike VandeVelde

    done before

    I saw Tesla do this with my own eyes in "The Prestige" ;-) Lit up a whole hillside of bulbs, pretty neat. So these guys don't impress me!

    The sun makes me sneeze too, especially through overhead wires or even scragly trees. I've heard it's a genetic thing. Same things with my 2 yr old son - also sneezes when I turn on the light in his room at night to see what he's yelling about. It's for real man!

  33. Anonymous Coward
    Anonymous Coward

    Like a whirlpool


    Gah. Nikola Tesla must be spinning in his grave. Which, ironically, could be done with remotely-powered electric motors. So perhaps it's not so bad.

  34. Anonymous Coward
    Anonymous Coward


    Finally a reality >:)

  35. prathlev

    Hm... tin foil hat alert

    There are some very interesting I-wear-a-tin-foil-hat-all-the-time comments above. I thought most people were at least moderately proficient in reading. ;-)

    To the anonymous poster @10:52 Fri 8th June: The article is from "BrainCourse", and "Creative Alternative" web site that professes methods of learning to use our brains one hundred percent. Sounds a lot like the old Einstein joke. (Which his memory doesn't deserve the blame for.) Related to Scientology maybe? I'll pass anyway... :-)

    And the one who asks: " do people think that Magnetic Resonance Imaging works!!!!!!" (oh wait, missing a question mark, so not a question, and I haven't seen that many exclamation marks since my last viewing Jeff K's "hoemapeg". ;-) Well: How do YOU think it works? The 'by "wobbling" the atoms inside you?' is not all wrong, but I think you paint the wrong picture. You make it sound dangerous, even lethal, when in fact no studies have shown that to be the case yet. MR is primarily a problem for people carrying electronics (and metals) inside them, like them "auto resize breast implants" and stuff like that.

    I agree that it's a burden to carry around these 60cm coils, and I am lay man on the matter so this comment may be misplaced, but hey: Computers started out big, and look now. Maybe we all carry around micro coils in 20-30 years. :-)

    Too bad Terrence didn't attack the Reg Staff by the way, otherwise I think it would be a nice FToW. :-D


  36. Aubry Thonon

    Re: Not all Tesla...

    "Just because the great man came up with a way of wirelessly transmitting power doesn't mean that he has dibs on all mechanims for doing this."

    ..he would if he had taken a US Patent, given how lax the USPO is with regards to restricting scope. ^_^

  37. Anonymous Coward
    Anonymous Coward

    Return of the wireless.

    Much as the inventors enthuse about this new technology, (or is it a re-invention of the wheel?) I cannot help but think that there are more dangers to this than are at first apparent. We already live in an ever increasing atmosphere of RF smog. (Any radio enthusist will confirm that.) I would suggest we need electricity measured in MHZ, which is, by definition, surely in the RF bracket, as much as a fish needs a bike! The more of these gizmos there are, the worse things will get. As far as magnetism being harmless, why has so much been spent on law suits in various countries by people living under power lines and becoming ill? Why are there massive signs at radar esatblishments telling people NOT to stand near radar antenna(whoops. nearly said aerial!) and why are pilots of radar equipped aircraft forbidden to switch on radar sets whilst still on ther ground? Anyway, switching lights on from a distance is no big deal. I turned my upstairs light on tonight from downstairs. Sure is a powerful thing, this 'ere sunken wiring!

  38. David Schreiber

    Late April First Post?

    Would someone please explain to us Non-MIT-trained, how a magnetic field is generated that does not contain an electrical component?

This topic is closed for new posts.

Biting the hand that feeds IT © 1998–2019