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Intel Demos Wireless "Resonant" Recharging

Al writes "Last Thursday researchers from Intel demonstrated a way to recharge electronics from about meter away using a 'resonant' magnetic field. At an event held at the Computer History Museum in Mountain View, the researchers showed off a pair of iPod speakers connected to a 30-centimeter-wide copper coil that received power from a similar, but larger, copper coil about a meter away. The recharging technique relies on a phenomenon called resonant coupling, in which objects can exchange energy when tuned to resonate at the same frequency. A similar approach was developed by researchers at MIT in 2007, and spun off into a company called WiTricity. This company has already developed a few products that use resonant coupling to recharge, including a car battery."

184 comments

  1. Pacemakers? by sexconker · · Score: 2, Interesting

    Pacemakers lol?

    Seriously, this is nothing more than a simple application of a simple science experiment.

    Wireless fields / broadcasts are a joke, and until we change the laws of physics, always will be. (Directed transmissions are not a joke.)

    1. Re:Pacemakers? by Culture20 · · Score: 2, Insightful

      You jest, but charging pacemakers or other internal devices would be almost the only practical use for this technique.

    2. Re:Pacemakers? by vertinox · · Score: 3, Insightful

      Pacemakers lol?

      If you think replacing a battery on an iPhone is hard, try replacing your own pacemaker battery.

      --
      "I am the king of the Romans, and am superior to rules of grammar!"
      -Sigismund, Holy Roman Emperor (1368-1437)
    3. Re:Pacemakers? by abigor · · Score: 4, Funny

      I saw a documentary called Iron Man where this was done.

    4. Re:Pacemakers? by ShieldW0lf · · Score: 1, Troll

      Didn't Tesla figure this stuff out decades ago, before the US government seized all his research?

      --
      -1 Uncomfortable Truth
    5. Re:Pacemakers? by draggie3k · · Score: 1

      You jest, but charging pacemakers or other internal devices would be almost the only practical use for this technique.

      i wonder if grandpa with a 30cm copper coil attached to his body would serve as a lightning rod...

    6. Re:Pacemakers? by mrdoogee · · Score: 1

      About a century ago. 1894 according to Wikipedia. With a patent in 1897. Good to know that Edison's megalomania only held us back for a century.

    7. Re:Pacemakers? by rsmits · · Score: 2, Interesting

      Pacemakers lol?

      Seriously, this is nothing more than a simple application of a simple science experiment.

      Wireless fields / broadcasts are a joke, and until we change the laws of physics, always will be. (Directed transmissions are not a joke.)

      I was doing this as a kid in the sixties with a one transistor radio powered by rf from the local broadcast station. The radio had two tuned circuits - one for receiving power, one for tuning to the station. It's exactly the same principle used here. So now we get thousands of new sources of radio frequency interference from these chargers! Thanks a lot.

    8. Re:Pacemakers? by Anonymous Coward · · Score: 0

      According to mythbusters, you pretty much have to put a door knob on your face before it makes a difference for lightning.

    9. Re:Pacemakers? by sexconker · · Score: 1

      You jest, but it's actually easier than an iPod.

      Pacemaker people often get leads for recharging, or an easy-access flap for replacement. You can even charge through the skin.

    10. Re:Pacemakers? by arkowitz · · Score: 1

      Any company not giving Nikola Tesla explicit credit for this can go frak themselves.

    11. Re:Pacemakers? by Bigjeff5 · · Score: 1

      Yeah, this is only a million times more efficient. This operates at the Watt level, not the MegaWatt level. It took massive amounts of energy to just barely power a device that uses far less energy than an iPod in your case.

      Also, regarding the radio polution, these resonance devices operate at very high frequencies, and as a radio afficianado you must know, higher frequencies mean less distance and less substantial objects can block the signal. Furthermore, differing frequencies don't interact with one another, and the required tuning for higher frequency devices is much higher than low frequency devices. Chances are the EM waves for this device couldn't leave a room or penetrate the skin.

      --
      Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
    12. Re:Pacemakers? by Culture20 · · Score: 1

      You jest, but charging pacemakers or other internal devices would be almost the only practical use for this technique.

      WTF? How is this a Troll? Wireless power loses energy, so the only places it makes sense are were wires can't go or batteries can't easily be replaced. ie In The Human Body. If you're going to moderate, think a little before applying -1 Troll or -1 Flamebait.

    13. Re:Pacemakers? by Anonymous Coward · · Score: 0

      looks like a troll got some mod points

    14. Re:Pacemakers? by Anonymous Coward · · Score: 0

      Nikola Tesla invented this concept first. http://en.wikipedia.org/wiki/Nikola_Tesla

    15. Re:Pacemakers? by vlm · · Score: 1

      This operates at the Watt level

      Chances are the EM waves for this device couldn't leave a room

      Ham radio is just not popular here on slashdot, oddly enough. Used to be a very popular hobby amongst the technologically advanced, now even the most obvious basics seem forgotten...

      FYI a couple watts in the 40 meter band (where this device operates) will easily communicate/interfere around the world... google for various combinations of "ham radio" QRP "40 meters" 40M ARRL "five 5 watts". The idea that "watt level" 7 mhz signals won't leave a room, is very incorrect.

      73 de n9nfb

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    16. Re:Pacemakers? by Dragonslicer · · Score: 2, Interesting

      Wireless power loses energy, so the only places it makes sense are were wires can't go or batteries can't easily be replaced.

      It's also useful for small devices that would be safer without exposed contacts. Electric toothbrushes are the first thing that come to mind, though I'm sure there are plenty of better examples.

    17. Re:Pacemakers? by David+Gould · · Score: 1

      If you think replacing a battery on an iPhone is hard, try replacing your own pacemaker battery.

      And, just to drive in the point, make sure you can do it with the engine running

      --
      David Gould
      main(i){putchar(340056100>>(i-1)*5&31|!!(i<6)<< 6)&&main(++i);}
    18. Re:Pacemakers? by Parallax48 · · Score: 1

      Electric toothbrushes can be charged using inductance, as they are incredibly close to their base station when put down. A simple solution would have the brush dropped into a plain circular hole in the base, with no exposed contacts, just a drainage hole. The base has a wire-wrapped core wrapped around this hole. there is matching coil in the brush. The two create a transformer when the brush is in the socket, transmitting the electrical power.

      What is special about this system is the long range. I am sure it trades off efficiency, size and manufacturing complexity to get it. Long range is a very very compelling feature.

    19. Re:Pacemakers? by shentino · · Score: 1

      [citation needed]

    20. Re:Pacemakers? by shentino · · Score: 1

      Taking into account how much of the inverse square attenuated radiation was actually available for the radio to absorb would be a better measure of efficiency.

      The earth receives but a minute teensy fraction of all the solar output the sun gives off in total...and it's still a big fat can of whoop ass.

      You need a friggin strong transmitter to overcome inverse square over any appreciable distance unles s you aim.

  2. Intel expects this technology will be a hard sell by Anonymous Coward · · Score: 2, Funny

    As everyone's credit cards were erased during the demo.

    They did expect users with paper currency and PMs would be more open to purchase.

  3. Oh this is going to look cool by ColdWetDog · · Score: 4, Funny

    At an event held at the Computer History Museum in Mountain View, the researchers showed off a pair of iPod speakers connected to a 30-centimeter-wide copper coil that received power from a similar, but larger, copper coil about a meter away.

    I'm having a little trouble here with the concept. Instead of small white box plugged into the wall we have these freaking huge copper wires running in circles everywhere. Just doesn't jibe with the trendy iPod image.

    Can you imagine a Beowulf cluster of these things?

    --
    Faster! Faster! Faster would be better!
    1. Re:Oh this is going to look cool by vertinox · · Score: 4, Funny

      Just paint the copper wires white.

      --
      "I am the king of the Romans, and am superior to rules of grammar!"
      -Sigismund, Holy Roman Emperor (1368-1437)
    2. Re:Oh this is going to look cool by mehrotra.akash · · Score: 1, Funny

      Can you imagine a Beowulf cluster of these things?

      that would wipe out every credit card in the neighborhood, not to mention HDD's and CRT's

    3. Re:Oh this is going to look cool by Hognoxious · · Score: 1, Funny

      Will it interfere with the reality distortion field?

      --
      Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    4. Re:Oh this is going to look cool by Anonymous Coward · · Score: 0

      And charge a lot for them to offset your ad campaign costs in which hipsters mock plugs.

    5. Re:Oh this is going to look cool by insnprsn · · Score: 1

      Can you say proof of concept? Make it work, then make it viable for use

    6. Re:Oh this is going to look cool by mehrotra.akash · · Score: 0, Troll

      someone here has forgotten the definition of troll

      http://www.answers.com/troll

    7. Re:Oh this is going to look cool by Hurricane78 · · Score: 1

      Well, I think being fryed (a little, or a little more) when standing in-between the devices, also does not "jibe" that much...

      Try to put them anywhere near me, and I will sue you to hell and back. ^^

      --
      Any sufficiently advanced intelligence is indistinguishable from stupidity.
    8. Re:Oh this is going to look cool by dontmakemethink · · Score: 2, Insightful

      Not only is it completely impractical, not only it is not original, another much more practical contact-free charging method has been in widespread use for over 10 years. Inductance charging is reasonably efficient and very handy for waterproofing rechargeable devices, like my Panasonic shaver (link to charger image). Not nearly the range of "resonant charging", but all the other advantages apply, and no tumors or pacemaker failures.

      --

      War as we knew it was obsolete
      Nothing could beat complete denial
      - Emily Haines
    9. Re:Oh this is going to look cool by Anonymous Coward · · Score: 0

      Guess what, inductance charging is the same thing just with smaller coils and less distance.

    10. Re:Oh this is going to look cool by Falstius · · Score: 1

      Your argument is effectively, "prove physical relation, break rules of physics" You can't make it smaller without making it less efficient. The resonance effect they are using to get decent efficiency degrades quickly once the separation is greater than the coil diameters.

    11. Re:Oh this is going to look cool by insnprsn · · Score: 1

      Yes, because nothing in history has ever been done better after being shown to be possible. I dont pretend to understand the science behind it because I dont

  4. Dumb question... by DoofusOfDeath · · Score: 2, Interesting

    Isn't resonant vibration the way tons of energy transfers occur, including plain old radio communication?

    What makes this so novel?

    1. Re:Dumb question... by Steegest · · Score: 1

      Lazy people can be even lazier? I.E. no more bending over to reach that last inconvieniently placed outlet...

    2. Re:Dumb question... by ColdWetDog · · Score: 0, Troll

      What makes this so novel?

      It's probably patentable in one way or another.

      --
      Faster! Faster! Faster would be better!
    3. Re:Dumb question... by EkriirkE · · Score: 1

      I think an air-core transformer is already prior art...

      --
      from 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
      to 45 2F 6E 40 3C DF 10 71 4E 41 DF AA 25 7D 31 3F
    4. Re:Dumb question... by neomunk · · Score: 2, Interesting

      80% power efficiency.
       

    5. Re:Dumb question... by Anonymous Coward · · Score: 0

      "80 percent efficiency within a range of about a meter"
      My power cord is longer...

    6. Re:Dumb question... by BeardedChimp · · Score: 1

      Electromagnetic induction is the way 'tons' of energy transfers. It is also how transformers work but it is only efficient at short range.

      This application is different in that it makes use of resonance to overcome these shortcomings. From wikipedia:
      "resonance comes in and helps efficiency dramatically by "tunneling" the magnetic field to a receiver coil that resonates at the same frequency. If resonant coupling is used, where inductors are tuned to a mutual frequency and the input current is modified from a sinusoidal into a rectangular or transient waveform, significant power may be transmitted over a range of many meters."

    7. Re:Dumb question... by mrdoogee · · Score: 1

      I thought that Transformers work because of energon cubes.

    8. Re:Dumb question... by 2gravey · · Score: 1

      and it's 100% efficient!

    9. Re:Dumb question... by Emb3rz · · Score: 1

      I'm not educated in the ways of electricity, so I don't know which one of these contradicts you, but I'll let someone smarter than me pick:

      • Impedance
      • Resistance

      Either way, it most certainly is NOT 100% efficient.

    10. Re:Dumb question... by 2gravey · · Score: 1

      Obviously nothing is 100% efficient, but copper over a short run is so damn close, you'd have to be a nitpicking ninny (or a physicist, which you are clearly not) to insist on the distinction. Go smoke some more of your iHerb and mellow out.

    11. Re:Dumb question... by Anonymous Coward · · Score: 0

      Resistance is the real component of impedance (ie. for DC circuits resistance = impedance). Impedance takes into account the phase difference between the voltage and current with the imaginary component being caused by capacitive and inductive components.

    12. Re:Dumb question... by Falstius · · Score: 1

      This is magnetic coupling taking advantage of the resonant frequency of the system and is strictly a local effect. Radio's are electromagnetic radiation, which is where electrical and magnetic fields sustain each other will travelling through space indefinitely. The energy in the oscillation of a radio wave does not decrease with distance, it just gets spread out over a larger area (or absorbed, but that isn't relevant to this).

    13. Re:Dumb question... by Falstius · · Score: 1

      This technology makes the very short range technique used in transformers work over a medium range (on the order of the coil diameter), but it is not and probably can not be a long range technique (like lasers). I only say probably and not definitely because I have studied science history.

    14. Re:Dumb question... by Roger+W+Moore · · Score: 2, Informative

      Obviously nothing is 100% efficient...

      Actually super conductors are. They really have zero resistance. Unfortunately the temperatures involved mean that they are not very practical.

    15. Re:Dumb question... by Parallax48 · · Score: 1

      [nitpick]
      How do you connect the superconductor to the grid? Is that connection also superconducting?
      [/nitpick]

      @2gravey - the impedance of the cord is nothing to the impedance of the transmission mechanism (those power pylons and transformers)

    16. Re:Dumb question... by i_b_don · · Score: 2, Informative

      um... what?

      Did you mean "the RESISTANCE of the cord is nothing compared to the impedance of the transmission mechanism"? Impedance is ideally lossless... the reduction in current comes from capacitance and inductance which only store and redirect current instead of turning it into heat like resistance does.

      And your nitpick doesn't make any sense either. Just because one part of a transmission line is super conducting doesn't mean it all is. It's like switching between different resistance cables in your power transfer... what happens in one part of the line doesn't mean anything about the rest of the wire.

      The real problem with the efficiency of super conducting cables is the cost that goes into keeping them cool. You have to count that massive expenditure of energy against it when doing efficiency calculations.

      In the end, 2gravey is right, copper is one hell of a good conductor (the only material that I know is better is silver, and it's not better by much) so its rarely possible to improve on a good copper wire other than to make it a thicker copper wire.

      d

      --
      all language nazi's will burne in heil!
  5. power consumption by mehrotra.akash · · Score: 4, Interesting

    what is the power consumption of the transmitting coil when there is no load coil, also, does the power consumption increase or decrease based on the number of receiving coils??

    and, what happens if you place a HDD, or your phone contains a HDD and is charged using this method, wont the magnetic field damage the magnetic media??

    similarly, magnetic fields can mess up CRT's, try taking a magnet to a CRT screen..

    1. Re:power consumption by vintagepc · · Score: 1

      Nah... If you get distortion problems it just means your CRT is incompatible with the new technology (That was meant jokingly, but I suppose it applies literally too!). You'd have to take it in to a repair center where they replace it with a brand-new LCD for twice the cost of the in-store model.
      Same with HDDs -->SSDs. I sense a business opportunity here :)

      --
      Evolution - Est. 4500000000 B.C. Don't piss in the gene pool.
    2. Re:power consumption by MBGMorden · · Score: 1

      Well, in reality CRT's are pretty much on their way out these days. Sure there are some uses for them, but they're somewhat specialized now. I haven't seen a CRT monitor on a store shelf in years. If you go to an online retailer they might have a FEW of them (Newegg currently lists ONE CRT monitor and 215 LCD monitors) but at roughly equivalent prices to LCD's (and any minor price advantage is usually offset by a higher shipping cost). The ones that ARE still out there working for regular home use have a limited lifespan.

      As noted CRT's on retails shelves are all but gone. In 8-10 years I'd guess that they'll be exceedingly rare in home settings at all. And realistically, I don't think any holdout with a 10-15 year old CRT still chugging along is going to be an early adopter in line for wireless recharging technologies . . .

      --
      "People who think they know everything are very annoying to those of us who do."-Mark Twain
    3. Re:power consumption by Celeste+R · · Score: 1

      you're surrounded by magnetic fields, whether it's from the power wiring in the house you live in or your wifi access point.

      I'm guessing that the most significant reason why they have antennas that size is because they're trying to -not- have it interfere with things (well, your old microwave will still do that, but you can't do too much about that aside from replace it).

      The threat from magnetic fields comes from strong magnetic fields (it polarizes the atoms). This is why magnets around CRTs is a bad idea, but that being said, it takes a SIGNIFICANT amount of power to make an amagnetic object behave in a magnetic fashion.

      --
      There are no perfect answers, only the right questions. More questions at http://foresightandhindsight.blogspot.com/
    4. Re:power consumption by Anonymous Coward · · Score: 0

      isnt wifi on electrical field, not magnetic??

    5. Re:power consumption by ckthorp · · Score: 1

      The magnetic coercion of a hard drive is so high that I doubt that these coils could cause the media to be damaged. However, the extra EMI might just make the logic circuits fail.

    6. Re:power consumption by mehrotra.akash · · Score: 1

      never tried it with a hard disk, but a small set of 2.1 speakers has caused me to lose a lot of data from floppy disks

    7. Re:power consumption by Hurricane78 · · Score: 2, Insightful

      And what about humans.

      You know that our brain and nerves work electromagnetically, and many processes in our body do not expect a strong magnetic field on the outside.

      A weak field, OK. But a strong one will be bad. So the question is: How strong is still OK, and is the one who defines this trustworthy?

      --
      Any sufficiently advanced intelligence is indistinguishable from stupidity.
    8. Re:power consumption by Anonymous Coward · · Score: 0

      It's electromagnetic. So technically it's both.

    9. Re:power consumption by PitaBred · · Score: 1

      There's a reason it's called an "electromagnetic field". It's both.

    10. Re:power consumption by ckthorp · · Score: 2, Informative

      That's a floppy. The magnetic materials are very different. Floppys are about 700 oersteds -- http://www.fujifilmusa.com/shared/bin/Degauss_Data_Tape.pdf Perpendicular HDs are much more (several thousand) -- https://www.mediaduplicationsystems.com/ProductDetails.asp?ProductCode=REM-1400NSA%20DEGAUSSER

    11. Re:power consumption by hedwards · · Score: 1

      That'll change as time goes by. The main use for CRTs has been in art for some time, but as the gamut, resolution and response time improves, there's going to be no justification for the added bulk.

      Personally, I wouldn't count on this sort of technology being of any use anytime soon, the current offerings like the products at wildcharge.com are likely about as close as we'll get. There's just way too many important things for this sort of thing to interfere with.

    12. Re:power consumption by Anonymous Coward · · Score: 0

      An MRI generates a tremendous magnetic field, many orders of magnitude stronger than these 30 cm coil loops...

    13. Re:power consumption by IorDMUX · · Score: 2, Informative

      what happens if you place a HDD, or your phone contains a HDD and is charged using this method, wont the magnetic field damage the magnetic media??

      Most HDD's are pretty well shielded, nowadays. Remember also that the receiving coil (in this case) is a 707 cm^2 wire coil, while the surface area of the hard drive in the magnetic field is likely no more than a few cm^2. (The energy absorbed by an object in this situation is proportional to its surface area in the plane perpendicular to the electric field, among other things.)

      does the power consumption increase or decrease based on the number of receiving coils??

      The power consumption in the primary would increase. Given the case of two coupled inductors (the two coils seen here), a mutual inductance couples the two and a "reflected impedance" is seen on each of them due to the effect of the other. In other words, if the receiving coil was consuming large amounts of power, a significant series load would appear on the transmitting coil, causing either a drop in the voltage and the transmitted power (if you hold the power consumed by the transmitting coil constant) or an increase in the consumed power (if you hold the transmitted power constant).

      --
      >> Standing on head makes smile of frown, but rest of face also upside down.
    14. Re:power consumption by PReDiToR · · Score: 1

      We needed a new "telly" last year, our old CRT had given up the ghost. We went shopping around (as one does when one wants a good deal on expensive technology) and saw a multitude of LCD and plasma screens.

      We saw pretty much the cheapest to the most expensive (approximates the the worst to the best) of these HD ready, DVB, HDMI, scart, give you a blowjob and do the dishes telescreens and we decided to go with a CRT anyway. The price wasn't the problem, it was the perceived image quality.

      In the opinion of my wife and I, LCD/plasma just isn't ready for putting in the corner of the room yet.

      YMMV and apparently does.

      --

      Do not meddle in the affairs of geeks for they are subtle and quick to anger
    15. Re:power consumption by vlm · · Score: 1

      You know that our brain and nerves work electromagnetically

      Actually, no. Your eyes are quite sensitive to EM waves in the just sub 1um range, and as a secondary effect, EM waves in the vague range of a kilowatt per square meter heat your skin just as much as sunlight does. Vision, and bulk thermal heating effects. That's about it for EM radiation effects on the body.

      Your neurons (assuming earth species) work on electrical potentials in the vaguely mV-ish range plus or minus an order of magnitude or two or so.

      Now, moving a charge carrier thru an immense magnetic field makes an electric field, that is whats theorized to cause any effects of "magnetism on the body".

      There is some pretty crackpotty stuff about certain organic chemicals and enzymes having a small dipole moment that may or may not react differently under extreme fields, but probably not even in a lab. If it were relevant, living things would probably evolve to be very sensitive to their magnetic alignment, which they seem not to be. If I got 0.005% better liver enzyme function if I slept aligned N-S, I probably would have evolved to sense that to get the free bonus, but thats not happened.

      and many processes in our body do not expect a strong magnetic field on the outside.

      The electrical signals in your brain make femto-tesla range fields, charges that move in a non-straight line, etc. So... uh... every brain thats ever existed has always floated in a femto tesla range field of its own making. So that certainly sets a low range of concern of about 1 fT below which our own brains create a field stronger than the external field of concern.

      Then there's the .1 mT -ish range earth's magnetic field. Which occasionally drops to zero. And probably, occasionally goes over it's normal range due to magnetic storms and stuff. Anything from the earth is green and organic and therefore good, much like, say, hemlock, or poisonous mushrooms. So, good old mother nature sets low range of 1 mT or so. It seems most species can't evolve a useful sense organ for "mT" level fields, strong indication fields of that strength are not biologically active.

      A kids toy bar magnet runs around single digit mT range, so I'd worry more about the red lead paint on the "N" side of the magnet, than the actual field itself.

      When you break out the liquid helium, then I'd worry about cryo accidents, suffocation / oxygen displacement accidents, and of course accidentally placing a body part between the "T" range magnet and something made of iron. Way down on the list of concerns, maybe there would be worries about the biological effect of the field.

      How strong is still OK

      Here's an interesting link from some green group, which may or may not be flaky, but seems remarkably reasonable to an engineer like me, and suggests fields stronger than current model MRI range are getting troublesome to humans.

      http://www.greenfacts.org/en/static-fields/l-3/4-interactions-body.htm

      Here's the world health organization's opinion. A gross generalization of their 30+ page report is don't worry be happy.

      http://www.who.int/entity/peh-emf/about/en/Static%20and%20ELF%20Fields.pdf

      and is the one who defines this trustworthy?

      Well, greenie luddites are probably as technophobic, and ignorant of what they fear, as a group can get, and they seem only mildly concerned about the highest field levels from the most powerful magnets being built in today's laboratories, everything else you'll ever experience is probably a factor of ten thousand to ten million lower field and probably a factor of more than thousands to millions safer, since risk is not strictly linear since we live in a planetary field and our own nerv

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    16. Re:power consumption by MBGMorden · · Score: 1

      Indeed. It all depends on what particular things about the image you like. CRT's can do non-native resolutions much better than LCD's can. CRT's generally have much better color accuracy as well. Their update time is also faster so there's less "ghosting" (though newer LCD's are much, much better at this than earlier ones). LCD's on the other hand tend to have more accurate picture geometry. They don't have the same problems with burn in. They burn less power, and their image is more "stable" (CRT's often have a wobbly appearance to the image for me. some much worse than others, but most that I've seen exhibit it to some degree). All LCD's are also flat screens whereas many CRT's are at least slightly curved.

      As to myself, I've got all LCD's for my computer screens. My bedroom TV and one living room is LCD (19" in the bedroom and 37" in the living room). I've got a 32" CRT in the other living room. I get by with any of them, but my preference is for the LCD's.

      --
      "People who think they know everything are very annoying to those of us who do."-Mark Twain
    17. Re:power consumption by Parallax48 · · Score: 1

      Usually with these devices, there are losses in the primary coil due to the current rushing around, but much less than you might expect - see http://en.wikipedia.org/wiki/Inductor#Stored_energy.

      As for the load on the primary increasing as secondary coils are added, see the First law of thermodynamics.
      "
      The increase in the internal energy of a system is equal to the amount of energy added by heating the system, minus the amount lost as a result of the work done by the system on its surroundings.
      "

      Secondary coils drawing power are causing the primary coil to do work.

      The way this stuff works in practice is that the primary coil makes a field that adds power...to the primary coil. This feedback loop reduces the power consumption of the primary coil. Secondary coils make this field weaker (by drawing power from it). The primary coil then has a lower positive feedback from its own field, so draws more power. This is the principle that makes electric motors draw more power when stopped / under load.

    18. Re:power consumption by BillX · · Score: 1

      No, magnets around CRTs (even little ones) are bad because they will semi-permanently magnetize any ferrous bits inside the CRT (or surroundings), slightly deflecting the output of the electron guns. (Or in case of big magnets, deform/rip the shadow mask off.) The amount of magnetization does not have to be much - on a color CRT, you only have to collectively kick a pile of these electrons over about one phosphor dot's worth (some microns) to completely screw up the colors.

      --
      Caveat Emptor is not a business model.
    19. Re:power consumption by TheSlashaway · · Score: 1

      Does not sound good for your body. I wouldn't buy or use one. Also, what if you sit in a metal chair near water, will it shock you?

    20. Re:power consumption by Celeste+R · · Score: 1

      Thank you for the clarification.

      --
      There are no perfect answers, only the right questions. More questions at http://foresightandhindsight.blogspot.com/
    21. Re:power consumption by Anonymous Coward · · Score: 0

      Well, magnetic resonance imaging exposes people to about 3 T, about six million times the recommended exposure limit for a pacemaker. This is considered a non-invasive procedure. Live animals have been exposed to fields stronger than 10 T (google "levitating frog") without negative effect. On the whole, neurons are much more resistant to magnetic fields than electronics.

    22. Re:power consumption by celtic_hackr · · Score: 1

      Well the field this article talks about is probably much stronger than a speaker's . Therefore, accordingly, it could have a negative impact on HDDs, if it is more than a a few tens of times stronger. It doesn't need to affect every molecule on a HDD to cause corruption. It only takes one weak spot. Unless you are proposing that a HDD has a perfectly uniform distribution of field strength with no weak spots. Which is fine ...

      in theory.

      But never occurs in application. I wouldn't feel comfortable having one of these anywhere near my HDD, and even less so near my many memory sticks. Or near my LCD monitors. What if only one in ten thousand bits gets flipped on an HDD, or one in 10 million? Are you really confident that we can produce an HDD that doesn't have 1 weak point every 10,000,000 bits? That's about a 99.99999% manufacturing precision. I'd love to see that. Especially now that densities are getter so much higher. High enough where we are reaching the maximum theoretical density.

      This is a bad idea, waiting for a disaster to cause And they're talking about putting these in laptops! Not to mention they are trying to claim IP on this. Even after admitting that Tesla invented it a century ago.

    23. Re:power consumption by hesaigo999ca · · Score: 1

      I would think the parts being able to be charged this way...car battery would be changed to this, while other appliances like HDD or LCD etc... might stay typical old fashioned plug in...baby steps here.

  6. This story resonates with me by Anonymous Coward · · Score: 1, Funny

    I get a real charge out of it.

  7. Nicola Tesla by FudRucker · · Score: 2, Funny

    i always wondered what that coil was for
    NicolaTesla
    he was recharging his ipod!!!

    --
    Politics is Treachery, Religion is Brainwashing
    1. Re:Nicola Tesla by theverylastperson · · Score: 0, Troll

      Thank You! I bet my buddy here that someone in the first 10 comments would mention Tesla.
      Of course he still thinks we're talking about music.

      --
      ed duval the very last person
    2. Re:Nicola Tesla by CarpetShark · · Score: 1

      If Tesla had an iPod back then, he must've been really into his music. I guess that finally explains why he started The Band

    3. Re:Nicola Tesla by dyingtolive · · Score: 1

      There is a lot of places in here where people mentioning Tesla are getting modded into the dirt. Is there some Edison fanatic out there with mod points today or is there something I'm missing? Genuinely asking.

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      Support the EFF and Creative Commons. The war is coming, and they're supporting you...
    4. Re:Nicola Tesla by vlm · · Score: 1

      There is a lot of places in here where people mentioning Tesla are getting modded into the dirt. Is there some Edison fanatic out there with mod points today or is there something I'm missing? Genuinely asking.

      A tesla coil is a simple resonant circuit, which in his day was basically a spark-gap radio transmitter, coupled to a quarter-wave helical/vertical quarter wave antenna. So, you make the resonator out of low resistance wire to get high efficiency, and make the quarter wave antenna high resistance/impedance to get crazy high voltages for a given power level. Works purely on EM waves coupling to the quarter wave antenna, not magnetically. It's just an old fashioned radio transmitter connected to a radio receiver antenna that operates at power levels that make sparks come out of the receiver antenna.

      The amazing never before seen device in the fine article, is a simple magnetic power transformer with non-coaxial windings cut in half, more or less, one half on the charging device, one half in the ipod/phone/laptop/car/whatever, with an air core instead of power transformer steel. That is why the cores are like foot on a side to charge an ipod... A close coupled steel lamination power transformer with "foot" dimensions will pass double digit kilowatts, this thing only passes "watts" at best.

      The device is claimed to be a magnetic device, but the windings and "air core" will make a poor antenna, so it actually outputs plenty of EM interference. Regular transformers don't emit much interference because it's easy to add a copper shield around the windings to prevent EM radiation, the frequencies of operation are low enough (25, 50, or 60 Hz) that the windings are incomprehensibly bad antennas, and the core laminations are too thick (eddy currents) to work well at higher frequencies. This "magnetic" gadget has none of those inherent design features to prevent EM radiation, therefore it's a scam to say its magnetic.

      So, they're either getting mod-ed down because the marketing claims it's magnetic and everyone knows teslas coil was a purely electromagnetic device, or, for slashvertisement purposes opinions critical of the false claim that its a magnetic non-EM radiator are being suppressed. Or they're being mod-ed down for the usual human stupidities on both sides. Hard to say if its overall good or bad.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    5. Re:Nicola Tesla by dyingtolive · · Score: 1

      So then, since its not a real magnetic device, aren't this device and the Tesla coil actually similar devices, except one is operating on the watt level rather than the kilowatt level? Admittedly that's a rather large difference, but still.

      --
      Support the EFF and Creative Commons. The war is coming, and they're supporting you...
    6. Re:Nicola Tesla by theverylastperson · · Score: 1

      All I did was comment that a comment had been made about Tesla and suddenly I'm a troll. I think it's Edison. He's still trying to keep Nick down. I was merely pointing out the fact that Tesla would come into play on the conversation rather quickly. I looked at some of the other comments after you made yours and you're right, someone isn't a Tesla fan. Of course, I'm still a troll or at least gnarled and bumpy.

      --
      ed duval the very last person
  8. Already have wireless power.... by Itninja · · Score: 3, Interesting

    ....it's called 'using batteries'. With a 3 meter range and relatively huge copper coils involved, how is this better that using batteries? Most devices use a transformer to customize the input for the device. With wireless power, would each device need some kind of special wireless receiver/transformer? And this would be better how?

    --
    I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
    1. Re:Already have wireless power.... by MBGMorden · · Score: 4, Insightful

      Um, this wasn't touted as a replacement for batteries. It was touted as a replacement for charging cables. IE, when I get home I throw my cell phone on the desk and it starts charging, rather than having to plug it into a cord.

      Personally, I CAN see some benefit to that concept. Not the least of which is that I just plain forgot to plug in my phone sometimes, but I ALWAYS sit it on the desk when I get home. It would also just clear up some of the clutter (I'm up to 4 different cables sitting on my desk now - a generic USB extension, a mini-USB connector, a cell phone charger, and an iPod connector).

      That said, every wireless power transmission scheme I've seen was EXTREMELY inefficient. Unless the technology could be made to work in the same ballpark efficiency as our current wired methods, I just don't see it as a good long term solution. If it was just a case though of "Yeah, we figured it out. Want one?" though then I'd be first in line.

      --
      "People who think they know everything are very annoying to those of us who do."-Mark Twain
    2. Re:Already have wireless power.... by Culture20 · · Score: 1, Funny

      Because now I can wardrive for power. Or, maybe I could drive a bumper-car on a road filled with these things.

    3. Re:Already have wireless power.... by Anonymous Coward · · Score: 0

      Lots of uses for this kind of technology. A single charing station you can set devices on to recharge, no cables involved, would be quite useful and is certainly possible. Cell phones, cameras, iPods, smart devices of many different types could be very conveniently recharged.

      Of course, I'd still rather see this kind of technology used for wirelessly powering vehicles, rather than charging our iPods... All in good time I suppose. Good to see more of Tesla's experiments put into practice.

    4. Re:Already have wireless power.... by mehrotra.akash · · Score: 1

      the article does boast of 80% efficiency..

    5. Re:Already have wireless power.... by Anonymous Coward · · Score: 1, Interesting

      The receiving end of this arrangement is a 12 inch copper coil. Unless your phone and iPod are fucking enormous, you'll still have to plug them into something. And you'll still have a tangle of wires bearing incompatible connectors.

      In other words, this "invention" is no more useful than a wire, but loses 20% of your power and takes up a shitload of space in your room. Count me out.

    6. Re:Already have wireless power.... by lobiusmoop · · Score: 1

      They are using a 7Mhz transmission for the power, so the receiver antenna needs to be roughly 10m long (1/4 wavelength). If they cranked up the frequency into the gigahertz range it would allow for a smaller receiver, but lower efficiency I guess.

      --
      "I bless every day that I continue to live, for every day is pure profit."
    7. Re:Already have wireless power.... by FudRucker · · Score: 1

      7Mhz, hmm i wonder what sort of mess this makes on the 40 & 71 meter HF band?

      --
      Politics is Treachery, Religion is Brainwashing
    8. Re:Already have wireless power.... by SparkEE · · Score: 1

      Well then, screw mobile device. How about using this to recharge electric vehicles? A 12-inch coil is no big deal in an automobile. I could see this being useful in something like the Volt or Circuit. You could install the larger coil at home and recharge your car without having to hook up a cable. It would be great for people without the luxury of a garage, and could mitigate the risks of a high power cable laying around outside all day.

      Even better, business could install the large coils and have special parking spaces that recharge the employees' or customers' cars during the day.

    9. Re:Already have wireless power.... by lobiusmoop · · Score: 3, Insightful

      FTFA:
      "the type of radiation shared between the two coils is nonradiative,"

      which I take to mean 'no more than a few Watts of power are involved', which is fine for mobile phones and the like I suppose.

      --
      "I bless every day that I continue to live, for every day is pure profit."
    10. Re:Already have wireless power.... by petershank · · Score: 0

      ....it's called 'using batteries'

      With this form of wireless power, you don't have to remember to replace the batteries, and you don't have to interrupt the device from working while the batteries are being replaced.

      ....With wireless power, would each device need some kind of special wireless receiver/transformer?

      Yes, just like wireless phones, which each need a special wireless receiver/transformer.

    11. Re:Already have wireless power.... by nine-times · · Score: 1

      It's not a replacement for batteries, it's a replacement for cables. Right now, even battery-powered devices need cables once the charge in the battery is used up. I'd love wireless power, to be able to ditch the rat's nest of cables I have everywhere going to every appliance and device. Unfortunately, I would guess that wireless power technologies would generally be (a) inefficient; (b) unreliable; (c) dangerous; or (d) some combination of the above.

    12. Re:Already have wireless power.... by Chyeld · · Score: 1

      SAMPLE APPLICATION:

      So when I get home today, I have a 'recharging' station where everything from my Wiimotes to my iPod get set so they can be plugged in and recharged. Each item has its own charger, with accompanying wall wart, and its own cord. I've attempted, in the past, to come up with 'stylist' ways over hiding this mess. LifeHacker had has many articles on building 'pretty' recharging stations, but nothing I've tried comes close to looking like anything more than a high tech tentacle monster attempting to rape my desk.

      Cue this setup, which in the far future when everyone stops screwing around with proprietary recharging schemes, where I could have the coils hidden in a compartment in the desk and simply have to place all the devices requiring recharging on top of it. No more playing musical outlets to manage all the wall warts, no more tentacle monster.

      Just a desk with a bunch of devices tossed on top.

              Now that's just the first thing I can think of off the top of my head. But there are all sorts of uses for a cordless method of supplying power within a yard radius. Any wireless device out there that is meant to be used in a fairly stationary location could benefit from this tech. Instead of batteries, outfit a house with strategically placed coils within the walls, the same way we do with outlets today. Now, anywhere you go inside the house is automatically powered. Of course, in that instance, you probably want to make sure you have the circuitry in place to 'cut' the power to the coils till there is a device to pull a load from, but these are things that are fairly easy to work out these days.

      Do I see this as something that will actually happen in the near future? No. This new twist on the tech is an interesting one, but we've known in theory about this sort of thing for a long time now and people just don't trust 'power in the air'. Just think how paranoid the "don't live near high voltage lines" people would be over this sort of thing. But that doesn't negate what is being done, it just means that I imagine the tech will be matured far far earlier than the society it is meant for.

    13. Re:Already have wireless power.... by DragonWriter · · Score: 1

      Well then, screw mobile device. How about using this to recharge electric vehicles? A 12-inch coil is no big deal in an automobile.

      I expect that you will want to transfer energy more rapidly to your car than enough to power a single speaker. For more power at similar range, you will probably need a bigger antenna.

      (And 20% power loss from transmitter to receiver is pretty horrible efficiency.)

      It would be great for people without the luxury of a garage, and could mitigate the risks of a high power cable laying around outside all day.

      So could a having a cable with a a cable reel and a fixed, locked cabinet, which would also give you a lot better transfer efficiency and capacity than this seems to offer.

    14. Re:Already have wireless power.... by Culture20 · · Score: 1

      Because now I can wardrive for power. Or, maybe I could drive a bumper-car on a road filled with these things.

      Again... Wasn't trying to troll. I was joking about the wardriving for power, but I was serious about the road. People have been complaining about batteries in electric cars, and alternatives like cable-cars leave power lines dangling all over the road. Wirelessly powered mini-cars might be a good option.

    15. Re:Already have wireless power.... by SparkEE · · Score: 1

      I expect that you will want to transfer energy more rapidly to your car than enough to power a single speaker. For more power at similar range, you will probably need a bigger antenna.

      (And 20% power loss from transmitter to receiver is pretty horrible efficiency.)

      Quite true, but I personally have no idea how this technology scales. I wouldn't automatically assume that the antenna size needs to grow with power throughput. If I were to assume anything, I would assume antenna size is a function of the frequency being used. Perhaps that frequency is a function of power throughput though.

      So could a having a cable with a a cable reel and a fixed, locked cabinet, which would also give you a lot better transfer efficiency and capacity than this seems to offer.

      Yes, that's also true. However, I personally think that anything that would make plug-in electrics more convenient would help the adoption rate, and thus is worth investigating. I don't think many people really welcome the idea of having to wind up the cable from the car when it's pouring rain and/or they're running late for work.

    16. Re:Already have wireless power.... by Anonymous Coward · · Score: 2, Funny

      FTFA:
      "the type of radiation shared between the two coils is nonradiative,"

      Wow, they invented non-radiative radiation!

      Wait a second...

    17. Re:Already have wireless power.... by WolfWithoutAClause · · Score: 1

      It's not dangerous (you can set the field strengths below the allowed limits, which are pretty conservative anyway).

      It is a *bit* inefficient. Wireless are about 30-70% efficient or so. For low power items like cell phones or Ipods that doesn't matter- these devices use very small amounts of power, so inefficiency is not such a big deal (actually batteries are only about 80% efficient anyway).

      There's no reason why it would be unreliable; actually it could well be more reliable as there's no connectors or power leads. I for one have destroyed one laptop by tripping over the power lead, so overall reliabilty is probably higher in fact.

      --

      -WolfWithoutAClause

      "Gravity is only a theory, not a fact!"
    18. Re:Already have wireless power.... by vlm · · Score: 1

      (And 20% power loss from transmitter to receiver is pretty horrible efficiency.)

      So... My gasoline car engine, is at best, 20% efficient, so it dumps 4 times the heat, and takes about 7 hours at highway speed to empty the tank. That requires a giant finned liquid cooled radiator with thermostatic control, coolant pump, running under pressure at 250 degrees, with electrical auxiliary fan, and it needs to be run outdoors in moving air or it will overheat.

      Historically, even engines at 1/4 the power (1/4 the heat output) still required a similar coolant system, just maybe it ran unpressurized at 180 degrees, maybe no thermostat, maybe no electrically controlled aux fan.

      An electric charger will still need to be outside, need actively pumped liquid coolant system the size of the entire front of the car with an electric fan running continuously. Probably not as elaborate of a cooling system as a modern gasoline car, but pretty complicated none the less.. It will not be able to dissipate that kind of power in an enclosed garage, other than maybe in the dead of winter. No idea how you'll keep animals and homeless away from the heat. Watching rain sizzle on the parked car will be weirdly cool. On the bright side you'll never need to scrape snow/ice off the windows, it'll be melted off.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    19. Re:Already have wireless power.... by Falstius · · Score: 1

      You're thinking of radiated power, this is magnetically coupled power. The wavelength is set by the resonant frequency of the coil and load. You want the coils to be much shorter than the wavelength to avoid radiating power (which is wasted).

    20. Re:Already have wireless power.... by Ken_g6 · · Score: 1

      Well then, screw mobile device. How about using this to recharge electric vehicles? A 12-inch coil is no big deal in an automobile.

      I expect that you will want to transfer energy more rapidly to your car than enough to power a single speaker. For more power at similar range, you will probably need a bigger antenna.

      (And 20% power loss from transmitter to receiver is pretty horrible efficiency.)

      The second page of TFA says they recently demonstrated a 3KW charger for electric vehicles.

      It would be great for people without the luxury of a garage, and could mitigate the risks of a high power cable laying around outside all day.

      So could a having a cable with a a cable reel and a fixed, locked cabinet, which would also give you a lot better transfer efficiency and capacity than this seems to offer.

      No, this isn't really good for home use. But imagine you're a cab driver, driving a plug-in hybrid. Gas is $2-$5/gallon, electricity is $1/gallon-equivalent. Now imagine you can pull up in front of a hotel or airport and automatically start charging your batteries, paid for with your toll pass or something similar, for maybe $1.50/gallon-equivalent, while being immediately available for a fare. Isn't that worth it?

      --
      (T>t && O(n)--) == sqrt(666)
    21. Re:Already have wireless power.... by MBGMorden · · Score: 1

      I don't think many people really welcome the idea of having to wind up the cable from the car when it's pouring rain and/or they're running late for work.

      Operate on the same concept as a winch. Flip a switch and let the cable wind up itself.

      There would definately need to be a failsafe somewhere though. I do see a possibility of an accident waiting to happen if a relatively high voltage electrical wire caught on something and a motorized winch kept pulling. Basically, if it met a threshold of resistance it would need to stop pulling.

      --
      "People who think they know everything are very annoying to those of us who do."-Mark Twain
    22. Re:Already have wireless power.... by Tacvek · · Score: 1

      A better solution would have been the splashpower product. The product in it's original incarnation, was a mat that was slightly bigger than a mousepad, and some small inexpensive receiver components. It is based on inductive coupling. The idea is that you could just lay your devices on the mat (a mat could support multiple devices simultaneously if they were small enough to fit.)

      Here is a concept image: http://web.archive.org/web/20050308101803/http://www.splashpower.com/_cms_images/sp_small.jpg

      Unfortunately, the company ditched that, for a design that is basically a cradle, which more or less completely eliminates any benefit the technology has.

      --
      Stylish sheet to fix many problems in Slashdot's D3: https://gist.github.com/801524
    23. Re:Already have wireless power.... by Anonymous Coward · · Score: 0

      Find out the level of rf magnetic field near the transmitter coil. Remember that the induced voltage on a conductor loop equals the change of magnetic flux in a unit of time. From this it is easy to see that a meagerly 10 uT of rf magnetic field at 13.58 MHz would generate a hefty 70 V of rf voltage in a loop with dimensions of 1 ft x 1 ft.
      .
      Think about induced (EMC) voltages in nearby mains conductors. The mode of transfer might be nonradiative but the induced rf voltages radiate like hell. One nonlinear component connected to a wire near the transmitter is results in radiation of VHF and UHF disturbances all around the setup.
      .
      Have these guys even seen the FCC rules regarding electromagnetic compatibility?

  9. Test for other sources by Lev13than · · Score: 4, Funny

    Did they ensure that the iPod speakers were properly shielded against RDF interference? Now that Jobs is getting his strength back, I fully expect that Apple devices will discard with batteries completely and just feed off his sheer willpower.

    --
    When you have nothing left to burn you must set yourself on fire
  10. Efficiency? by juanergie · · Score: 3, Insightful

    Anybody familiar with the efficiency of this process? What fraction of the wattage is lost during transfer?

    --
    Aeroespacio.org
    1. Re:Efficiency? by Darkness404 · · Score: 0, Troll

      I love it how some mod managed to moderate about 50% of the comments here trolls... Including this one which actually isn't a troll.

      --
      Taxation is legalized theft, no more, no less.
    2. Re:Efficiency? by Quantumstate · · Score: 1

      I you RTFA it said 80% for 1m range.

    3. Re:Efficiency? by Anonymous Coward · · Score: 0

      I attended a talk given by Marin Soljacic. This is the same method. The first demonstrations were roughly 50% efficient, don't know how much they've improved since then, but the technology itself is theoretically very (~90%) effiicient.

    4. Re:Efficiency? by eliphas_levy · · Score: 1

      From TFA:
      "For the Intel project, the large coil was hooked up to electronics that produced a current oscillating at seven megahertz. The receiving coil was tuned to the same frequency, and thus is able to accept an energy transfer with about 80 percent efficiency within a range of about a meter, says Josh Smith, the lead researcher on the project."

      --
      eliphas
    5. Re:Efficiency? by Anonymous Coward · · Score: 0

      And another question, where is this energy lost to? Will all the objects in the proximity of the charger heat up?

    6. Re:Efficiency? by hasdikarlsam · · Score: 1

      It'll attempt to induce electric currents in them.. ...yes, in practice, they'll heat up. Eventually, all that electricity turns into heat.

  11. We owe thanks to.... by Anonymous Coward · · Score: 2, Insightful

    Nikola Tesla and that crazy discovery of wireless energy transfer. Next time you power up your gizmo (via AC to DC conversion) raise a glass to the man who started it all!

    1. Re:We owe thanks to.... by vamidus · · Score: 1

      from WiTricity site: "...WiTricity technology for power transfer is different than the technologies proposed by Tesla, but his work is referenced and acknowledged in the scientific articles published by WiTricityâ(TM)s founding technical team..."

      --
      èåæç©
    2. Re:We owe thanks to.... by Ungrounded+Lightning · · Score: 1

      Tesla coupled the resonators with the electric field. This couples them with the magnetic field.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  12. Wasted Energy by wjousts · · Score: 3, Interesting

    So in this era of concern about energy supplies, we have a new way to charge our phones that is less efficient and will waste a ton of energy. But at least we won't trip over any cables.

    1. Re:Wasted Energy by twistedsymphony · · Score: 1

      how much energy are we saving by not manufacturing and eventually disposing of those cables?

      Also keep in mind that it's 80% efficiency at distance, I'm sure it's higher at close range (eg: a charge plate on your night stand that your phone sits pretty much directly on) and once the technology is being mass produced, just like every other product on the planet improvements will be made to improve it's efficiency over time.

      just because it's not perfect RIGHT NOW doesn't mean it wont be, but making it RIGHT NOW will often allow us to reach that pay-off point sooner. I also see this tech being beneficial for other applications... like putting a solar panel on on the roof of my garage and using this tech to charge the battery of my electric vehicle by simply parking in said garage.

    2. Re:Wasted Energy by wjousts · · Score: 1

      Well, that's a fair point on manufacture and eventual disposal of cables, but those are one time charges, so the whether or not it balances out in the end will depend on the lifetime of the device in question, something that is disturbingly short in many devices. Probably a far more efficient solution would be standards for chargers so that you don't need a new charger for every device.

      The fact is that this will never be as efficient as using a cable unless you can change the laws of physics. It'll have some applications, medical devices come to mind and I like your solar garage idea, but in general I think it's a bit of a non-starter unless you have plenty of clean energy to waste.

    3. Re:Wasted Energy by rs79 · · Score: 1

      Capacative inductance isn't exacly new. Around here some guy (no, not me, I'm crazy not stupid) that took two 50 gallon drums, wrapped them with two miles of thick copper wire and put them at the end of his property near some electric transmission wires. Then he ran wires from them to his grow op.

      It took Ontario Hydro about 2 weeks to find him and bust his ass.

      Point is you could probably at least charge an ipod if you live close to transmission lines.

      --
      Need Mercedes parts ?
    4. Re:Wasted Energy by Quantumstate · · Score: 1

      But you should also bear in mind that the coil they used was fairly large so if you shrank it then the efficiency would drop.

  13. Similar technology already in Wacom tablets by Captain+Spam · · Score: 1

    Isn't resonant coupling what Wacom tablets use to both power and communicate with their styluses and pucks (kinda-sorta tablet mice)? I know it's not technically "charging" either of them, per se, but it IS powering them, and it's done by resonance coupling.

    --
    Demanding constant attention will only lead to attention.
  14. Good luck with the FCC by odin84gk · · Score: 1

    7MHz? Good luck getting that through the FCC regulations on radiated emissions, not to mention all of those HAM operators. However, if they do achieve 80% efficiency then I will wish them the best of luck.

    1. Re:Good luck with the FCC by moon3 · · Score: 1

      Exactly, they achieved to build very powerful emitter, something that FCC is looking for like hawks to weed out from any consumer electronics.

    2. Re:Good luck with the FCC by Areyoukiddingme · · Score: 1

      Read other comment threads. It's not radiative. Therefore the FCC will neither notice nor care. It requires a RESONANT antennae to even pick it up. Your standard TV/radio/etc/ antennas aren't built to resonate. They wouldn't work if they did.

  15. useful, but dangerous by Vanderhoth · · Score: 2, Funny

    I read about this sort of thing awhile ago. http://www.pwrmat.com/ There would be some nifty applications, you could build this sort of power distribution system into a wall. Then you just have to be within the proximity of the distributor. It would primarily be a convince/lazy thing, but at least you wouldn't have to worry about your kid putting a fork in a wall socket. Then again by doing that you could be removing a natural selection factor and end up with even more stupid people that otherwise would have been electrocuted and taken out of the gene pool.

    1. Re:useful, but dangerous by vlm · · Score: 1

      at least you wouldn't have to worry about your kid putting a fork in a wall socket.

      Adding up all my wireless devices, a hundred watts delivered might be a power level that would be useful to me. Less than that, don't bother, more than that... read on for why that would be bad.

      So, at 20% efficient, my 100 watts delivered, dissipates 400 watts into heat. I'm guessing a surface area of a square foot or so. It'll be a nice space heater on 24 hours a day. Not so bad in northern climates in the winter. Not so good in the summer. A couple hundred watts with no ventilation, lay some papers on it, maybe not hot enough to ignite the paper, but easily hot enough to melt xerox/laserprinter toner.

      I would worry a lot more about my wedding ring acting as a single turn transformer secondary. Lets figure it would adsorb the full power level. The effect on my finger would be roughly like, touch skin w/ 100 watt soldering gun and pull trigger. In other words, if I move my hand quickly to place and remove my recharging devices, in less than a second, it will be uncomfortable but no damage due to thermal mass if starting from body temperature. But, hold my finger there for ten seconds, serious burn damage, hold my hand there a minute and its definitely emergency room time/burn clean off. Also for a good time toss my round key ring on the table next to my phone, I estimate red hot in about 20 seconds if I guessed an appropriate wire gauge equivalent for my keyring's ring...

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    2. Re:useful, but dangerous by hedwards · · Score: 1

      Lazy is one aspect, but the main draw is that these sorts of devices are meant to power multiple different types of gadgets and to use less power when just plugged in.

      And when we get a standardized option available manufacturers wouldn't have to include a charger because we'd be able to use the same one that we're using for most of our other devices.

    3. Re:useful, but dangerous by kimvette · · Score: 1

      It wouldn't be a lazy thing. It would mean I wouldn't have to bring a cellphone, external HDD, laptop, PDA, camera, and laptop charger/power supply with me. One charger would handle it all. This means when I travel I can pack significantly lighter, draw less suspicion from "Security Theater" "cast members" ;) (yes, I am equating Homeland Security to Mickey Mouse), and having need of only one type of charger, it would be harder to forget the wrong one. If I needed to buy one after forgetting the one-size-fits-all charger, I could buy one anywhere when I reach my destination.

      It has nothing to do with being lazy. It's also a hell of a lot more environmentally-friendly because I wouldn't have to pay for the manufacture of many different proprietary power supplies.

      --
      The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
    4. Re:useful, but dangerous by Areyoukiddingme · · Score: 1

      That's how it works if you're being exposed to radiated energy, yes. We're not talking about radiated energy. We're talking about paired resonating antennas. Your wedding ring or key rings (and keys) won't resonate with the charging antennae and therefore won't pick up any power. The same goes for paper and toner.

      The MIT group decided to get cute with their version and took a group photograph with a bunch of them standing between two operating coupled antennas transmitting and receiving enough power to light up an incandescent light bulb. None of them were busy slapping out a fire in their pocket, or running around shrieking because the metal fillings in their teeth were heating up. Resonant power transmission is both considerably safer than radiated power transmission and considerably more efficient.

  16. We need a standard for this by Animats · · Score: 3, Insightful

    There are at least four schemes for short-range wireless power transmission around. This needs to be standardized so it can be deployed.

    The very short range ones, which couple a tabletop pad to a device on it, would be most useful. All the little stuff that needs recharging should be on the same system, with recharging pads in bedroom, office, hotel room, car, airline tray table, Starbucks, etc. Unless the players get together and agree on a standard, this is going nowhere.

  17. Troll Explosion by Anonymous Coward · · Score: 0, Informative

    Why are there so many replies in this topic modded as "Troll"? Even ones that clearly are not trolls. Is someone trolling the mod system?

    1. Re:Troll Explosion by Anonymous Coward · · Score: 0

      I blew the last 4 of my mod points to correct some more egregious troll-marking.

  18. Dang! by NES+HQ · · Score: 1

    I guess we're going to have to stop using those 'wireless power' jokes that pop up whenever we come across equipment that's been unplugged!

    1. Re:Dang! by Samah · · Score: 1

      *Irish accent*
      Have you tried turning it off and on again?

      --
      Homonyms are fun!
      You're driving your car, but they're riding their bikes there.
  19. Intel demonstrates wireless power for the home by David+Gerard · · Score: 0, Offtopic

    A future without batteries -- no need to charge phones or MP3 players, or even electric cars. No lost phone chargers, no running out of power sockets. Intel chief technology officer Justin Rattner demonstrated a Wireless Energy Resonant Link as he spoke at the annual Intel developers forum in San Francisco yesterday.

    Rattner demonstrated this by causing his ears to light up at 60 watts of power a yard from a power transmitter operated by his assistant Igor. Only four journalists were incinerated when the power earthed through them from his fingertips.

    Rattner reassured us that pumping kilowatts of power around the home through magnetic induction power is absolutely harmless. "The human body is not affected by magnetic fields," he said as one journalist with a pacemaker collapsed and another with a knee replacement watched his leg catch fire. "There's no danger whatsoever from it, any more than there is from mobile phones cooking your brain, microwave leakage blinding you, chemical waste unraveling all the DNA in your balls or statistical clusters of kids with cancer wherever high-tension power lines run overhead. Asbestos and thalidomide were horribly slandered in their day too."

    "Of course, Nikola Tesla did it first in 1899," said enthusiast Albert Tedious-Anorak, 54, of Little Boring. "I detailed this at length on Wikipedia, but they refused to believe the value of my revelations on this matter due to a conspiracy of Edison fans amongst the site administrators."

    --
    http://rocknerd.co.uk
  20. Powercast released wireless power products in 2007 by TheNarrator · · Score: 1

    http://www.powercastco.com/

    True Wireless Power

    Powercast recognizes there are several alternatives available for powering devices without the use of wires, each with different addressable markets. The alternative methods may seem similar on the surface, however, they offer limited solutions. Powercast is the only company with the technology and component-level products to deliver continuous charging, and provide its capability at a scalable distance.

    They even won a best of CES 2007 award from CNET:

    http://reviews.cnet.com/8301-12760_7-9673092-5.html

    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

    Stuff like this comes up all the time but disappears down the memory hole very shortly thereafter.

  21. Hippies afraid of brain tumors will get this banne by Anonymous Coward · · Score: 0

    They already afraid of Cellphones

  22. Tesla would be proud. by Kotoku · · Score: 2, Funny

    Tesla would be so proud, many years later we are finally honing and putting to use technology that was before it's time.

  23. I see a lot of... by seramar · · Score: 1

    I see a lot of you saying things like, "big deal," "this idea sucks," "just use batteries," etc. As though the current implementation is the final version of this technology. I'm surprised that, on /. of all places, you guys aren't thrilled that this implies in the near future you won't even notice this technology... it ought to just work. Instead you're all bashing it and claiming it's a bad/stupid idea and implying they ought to just scrap the whole project. I say - keep working on it, no matter how ugly those coils are, because I know sooner or later, I won't even see the coils anymore.

    --
    australian project gutenberg is better than the original.
    1. Re:I see a lot of... by vlm · · Score: 1

      it ought to just work. Instead you're all bashing it and claiming it's a bad/stupid idea and implying they ought to just scrap the whole project.

      It sets off all the scam detectors for anyone that knows anything about power transmission, magnetic induction, medical diathermy machines, power transformer design, air core RF chokes/transmission lines, pretty much everyone in the field but gullible journalists.

      No explanation of how it works. No reason I've seen that explains why this would not have rolled out, say, 60 years ago to recharge WWII era army walkie-talkies. Nothing new in the magnetic world other than improvements in permanent magnet material science, mu-metal shielding is "cheaper", and superconductors, all of which have nothing to do with this product. Well, there are some advances in higher permeability materials, but the whole point of this product is to use an air core inductor. So, what are they doing with 1890-ish era technology that hasn't been done until now?

      How great it would be, if only it were true, is more appropriate for religious recruitment than electrical engineering. Of course it's possible to make jokes about optimistic electronic device data sheets, but this is carrying it a bit far.

      The overall effect is very similar to handing slick marketing brochure for a perpetual motion machine to a P.E. or thermodynamics engineer. Just gonna get laughed at.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  24. New Palm Pre does this now by Dcnjoe60 · · Score: 1

    The New Palm Pre does this now, just not across a large distance. The Pre has the alternate charger that you just place your Pre on (no wires to hook up or plug in to the Pre itself) and it charges through the back of the phone. Pretty cool, actually.

  25. Samer Theory? by kenp2002 · · Score: 1

    As a long time listener of Garage Logic on AM1500 (I only had AM in my car growing up, go fig) they frequently refer to a guy named Samer (sp?). He had a theory that the reason people, as a whole, have lost it, is that all the electromagnetic noise and radiation we have created litterally is frying out brain's ability to function normally.

    With all this talk about wireless charging and what I see in the world, I am starting to wonder if this Samer theory has legs... and if so what are the implications on humans?

    We know power lines can confuse cows internal compass. We've seen radar stations toss migratory birds a curve ball. What are the larger implications on humans since we've never really looked into how much all that 'noise' effects us.

    Simply ask yourself this: You are in a room with 5 people in silence. Any stress? Ok now as the noise increases, does the stress? Now ask this: what about all the noise you don't perceive but still might pick up... is this going to be just more noise and if so what are the implications if we assume the Samer theory has some validity.

    --
    -=[ Who Is John Galt? ]=-
  26. Induction FTW by jtownatpunk.net · · Score: 1

    When I was a kid, I had an electric toothbrush that charged via induction. Not the same thing this article is about but it seemed like magic at the time. Set the plastic toothbrush in its plastic base with no metallic contacts on either and it would charge. I was just a kid but even I knew you needed conductive material to conduct electricity and plastic wasn't conductive. (I thought my grandpa was pulling my leg and taking the battery out and charging it at night while I was asleep.)

    1. Re:Induction FTW by Anonymous Coward · · Score: 0

      my philips sonic-care tooth brushes will charge when placed in their plastic chargers. i have often wondered why more electronics are not being made with a flat mousepad sized structure where you can just lay your equipment on it and it recharges.

    2. Re:Induction FTW by Tacvek · · Score: 1

      Yes. Especially if a standard emerged, such that you could place multiple devices on a single mat. That was part of the original design of the SplashPower system. A more realistic implementation is the pwrmatt. (http://www.pwrmatt.com) (due in Fall 2009). Unlike the SplashPower proposal, this one starts out assuming devices will not already have the system built-in, so they will be selling what are basically plastic protective covers for devices that have the power receiver built-in. I'd be very surprised if they would not be very willing to negotiate with device manufacturers to incorperate support directly into the product. That is of course the ideal solution. Unfortunately, it appears that for most devices the supported solution will be a small pad with a cable that you connect to the device.

      If they are smart, they will also make the receivers in extra thin form available to hobbyists at minimal cost so people like you and me can integrate the technology into existing product. (Pop the case off your cell phone, put the receiver in a spot with a bit of room, and solder the leads to the USB power pins.)

      --
      Stylish sheet to fix many problems in Slashdot's D3: https://gist.github.com/801524
  27. got your crowbar ready? by Anonymous Coward · · Score: 0

    I hope nobody throws a bunch of these off a cliff.

    It could cause a resonance cascade.

  28. No real porn use, so it's on to advertising by Anti_Climax · · Score: 1

    Make it cheap enough and combine this with cheap electronic paper and we could have store aisles stocked with animated labels on anything big enough to carry a receiving antenna.

    If you think walking with your child down the gauntlet that is the cereal aisle is bad now...

    --
    Even people that believe in pre-destiny look both ways before crossing the street.
  29. charging dish by wren337 · · Score: 1

    I can imagine a dish or plate on top of your dresser where you can throw your ipod, phone etc at night and it charges without having to plug it in.

  30. Nikola Tesla, thou art avenged! by crmartin · · Score: 1

    Hmmm. Resonant coupling, magnetic fields, wireless power transmission, where have I heard this before?

  31. It pays off to be paranoid... by Chrutil · · Score: 1

    ...when your tinfoil hat can save you from brain cancer... ^C

  32. Begining baby steps of a new technology. by ACMENEWSLLC · · Score: 1

    So here is what I imagine. You know how a generator works, right? http://en.wikipedia.org/wiki/Electrical_generator Spinning copper wire around a shaft generating a current. And something has to spin the shaft.

    With this, the idea is that the generator is something resonating. e.g. It is just moving back and forth. So you make these very small, and put them inline with a battery. If you come within a resonate field, your batteries are automatically charged.

    There is a lot of waste. It's never going to be as energy efficient to plug one of field generators into a wall to charge up, versus an electrical cord. However, what if you use other power sources? Solar for example. Plug in a resonate field generator into a solar source, and have it generate this field all day long. You come home, leave your cell phone and Laptop unused on your desk, and by morning it is charged. That's the idea, at least. Baby first steps.

  33. Nothing new here by kpainter · · Score: 3, Informative

    A company I worked for was charging the batteries in medical implants in this manner 10 years ago. In fact, the implant's charge coil is inside its Titanium case. The magnetic field goes right through the case. The charger had a class E amplifier. It worked very well. I would not doubt if this company already has a patent on this technique.

    1. Re:Nothing new here by Anonymous Coward · · Score: 0

      Of course there is nothing new here. Nicola Tesla was doing this stuff like 100 years ago.

      http://www.wirelesspowerconsortium.com/technology/resonant-coupling.html

    2. Re:Nothing new here by Anonymous Coward · · Score: 0

      I'm not sure you can really patent http://en.wikipedia.org/wiki/Faraday's_law_of_induction

      Then again, if you were very convincing...

    3. Re:Nothing new here by Anonymous Coward · · Score: 0

      Tesla already has the patent for this. It's ether an air gap transformer (my soniccare tooth brush has one. Charges with no connecting wires.) or is a high frequency transmitter/receiver.

    4. Re:Nothing new here by IorDMUX · · Score: 1

      This wireless charging/powering is by no means a new technique. My masters thesis included plenty of material and research on this topic, and I was referencing papers on wireless powering for implants as far back as the 70's. The class-E amplifier driving an inductive coil resonantly tuned with a receiving coil is the standard architecture used by decades.

      I'm confused at the submitter's hailing 'resonant coupling' as a (seemingly) recent advance, as resonant coupling is simply what happens whenever a tuned transmitter and receiver antenna communicate. In communications devices, the tuning is broad so that the receiver takes in a wide range of frequencies which are filtered out down the line. In power transmission devices, the tuning is much more narrow, as only a single frequency (the power wave) is transmitted.

      Ironically, [please tell me I've used that word correctly] what makes wireless powering and charging more feasible today than 20 years ago is not an improvement in the electromagnetic theory of wireless power. Rather, it is a combination of a reduction in the power requirements of the receiving device due to advances in low-power electronics, as well as an improvement in evolution-based software which can simulate and design better and better directed antennas--something which by-hand design has never been able to do. All in all, though, it's a nice demo but isn't much in the way of new and useful science.

      --
      >> Standing on head makes smile of frown, but rest of face also upside down.
    5. Re:Nothing new here by Quantumstate · · Score: 1

      They did successfully patent the online quiz. I would definitely be worried.

    6. Re:Nothing new here by TheNarrator · · Score: 1

      These guys developed the same technology too. They have released commercial products, demoed and won awards at many trade expos and you can even order a developer kit:

      http://www.powercastco.com/

      It's amazing the amount of unfounded disbelief and misunderstanding of this technology on this thread.

    7. Re:Nothing new here by kpainter · · Score: 1

      I'm not sure you can really patent...

      I am pretty sure you can. This is the application of the law of induction to specifically charge a battery. Besides, from what I have seen, you can patent almost anything. When I worked for that company, our competitor had patented the concept of using 9 Volts in an implant. I am serious. We had to avoid using that specific voltage. They also had patented the concept of storing the implant settings in an eeprom. Note that both of these were specific to medical implants. Not too sure how valid these patents are but they have more money than god and love to sue.

    8. Re:Nothing new here by kpainter · · Score: 1

      Tesla already has the patent for this

      Don't patents expire after 20 years? Besides, he is dead.

    9. Re:Nothing new here by neonsignal · · Score: 1

      reference from wikipedia:
      J C Schuder. "Powering an artificial heart: Birth of the inductively coupled-radio frequency system in 1960". Artificial Organs. Vol 26, no 11, pp 909-915, 2002.

  34. oblig HL by Theodore · · Score: 1

    "I never dreamed I'd see a resonance cascade failure, let alone create one"...

  35. Sounds very similar to... by strangeattraction · · Score: 1

    This all sounds very similar to that new fangled gadget called a radio. I read about them here. http://en.wikipedia.org/wiki/Radio

  36. Anonymous Coward by Anonymous Coward · · Score: 0

    Gee, we had something similar in 1965 in the form of an electric toothbrush... the primary side of the "transformer" was the A.C. line, the secondary was inside the body of the toothbrush motor body and it recharged every time you put it on the stand. They increased the efficiency by having a "pole piece" sticking up inside the body of the toothbrush motor when it was in the charging stand, but other than that it was nothing new.

    EMI all over the place just because people don't want to plug something in? No thanks. Efficient it ain't. Safe? Not for all the credit cards and other magnetic media in your wallet.

  37. Other Stuff too by Anonymous Coward · · Score: 0

    A few years ago, I had an powered toothbrush set that charged that way - bought it in a branch of the LIDL supermarket.

  38. thinkgeek -- Wireless Extension Cord. by Anonymous Coward · · Score: 0

    How does this compare?
    thinkgeek already has a wireless extension cord (110v A/C) if Im gonna fry something, use microwave!

    link: http://www.thinkgeek.com/stuff/41/wec.shtml
    image: http://images.thinkgeek.com/products/zoom/wec.jpg

    pay no attention to the fact this was an april fools joke originally... Since I believe science fiction is based on reality (though not always implemented as such) this must be real too!

  39. Oh, wow! by frank_adrian314159 · · Score: 1

    They've recreated the technology in my rechargable toothbrush! This is a true breakthrough. I can't wait to see what's next! Maybe a wireless communications device? Or a horseless carriage? Oh, the wonders of the modern scientist!

    --
    That is all.
  40. Worse than credit cards... by Roger+W+Moore · · Score: 1

    What happens if it happens to "resonantly connect" with the springs in your sofa or other metal loops in your house where passing a large current and the associated heating may lead to a fire? The chance of something being exactly the correct dimensions may be small but how small exactly given the number of different locations this might be deployed in? You'll probably need some safety system to ensure that this does not happen.

  41. Not quite the same situation as NMR by Roger+W+Moore · · Score: 1

    ....but that is a constant (in time) magnetic field. Living creatures can sustain far higher fields than that (lookup the video of the flying frog on You Tube - this uses fields ~10 times higher than NMR to suspend creatures and objects through diamagnetism). I doubt there is a problem for a varying magnetic field but the situation is not exactly the same.

  42. Another non-story from Slashdot by Anonymous Coward · · Score: 0

    Another non-story from Slashdot that advertises a magazine. Was someone paid for this Slashvertisement?

    This is old, old technology, with no new elements.

  43. Wireless power... by JoCat · · Score: 1

    Sometimes referred to as lightening.

  44. Exposure to EM radiation by Anonymous Coward · · Score: 0

    The people behind these resonant antenna ideas usually seem to ignore the effects of large electromagnetic fields on biological tissue. It is a risk to have a rf magnetic field of say 30 microteslas at f > 20 MHz in a region with human access. There are very strict rules of the exposure limits based on the ICNIRP guidelines

    http://www.icnirp.de/documents/emfgdl.pdf

    The people developing magnetic resonance imaging devices (MRI) have struggled with the issues of induced rf currents and rf heating (SAR) for a long time. They are using similar frequencies but lower average rf magnetic fields because of the safety limitations. Kinda funny seeing this kind of hype where the safety point of view is completely forgotten. Maybe someone just rewrote the Maxwell equations...

    Think what happens when a microwave oven leaks rf. Remember the discussions of "dangerously high" rf radiation levels from cell phones. It is the same mine field here.

  45. Cost! by KiwiCanuck · · Score: 1

    80% efficiency looks good on paper. However, will energy stay cheap such that one can accept a reduced efficiency? This would work wonders on large scale. Electric cars that don't need a huge battery packs. Just some ultra caps..

  46. Heart surgeons don't do that though... by DRAGONWEEZEL · · Score: 1

    They put you on bypass machine, which pumps blood for you. It's not the same at all, but it's not all that much different. It's amazing how mechanical surgery is.

    --
    How much is your data worth? Back it up now.
    1. Re:Heart surgeons don't do that though... by David+Gould · · Score: 1

      Yeah, I know, but one tries not to let facts get in the way of a good joke. (Funny, a near-identical exchange followed the last place I saw that joke posted.)

      Maybe it would work better with brain surgery. Or, if the mechanic was allowed to stop the engine but had to do major work on the car's electrical system without losing my radio presets.

      --
      David Gould
      main(i){putchar(340056100>>(i-1)*5&31|!!(i<6)<< 6)&&main(++i);}
    2. Re:Heart surgeons don't do that though... by DRAGONWEEZEL · · Score: 1

      lol sorry, I work in Healthcare so It's hard not to debunk myths like this. 8')

      BTW, in my car, my radio presets are flashed (stock 2000 pontiac monsoon stereo) It's so nice to disconnect the battery and still have stations set. It's especially good since my display backlight died a year ago. I'm just now getting around to replacing it. I've got a sony MEX-5700 coming that I'm waiting on installation funds to have it put in. I hope it has the same feature!

      --
      How much is your data worth? Back it up now.
  47. Looks like the secret Intel Police.. by Zarf_is_with_you · · Score: 1

    Looks like the secret Intel Police secured the Missing Tesla Documents and have been working on it in secret at these years. They cant touch me now that the secret is out *&%#$( NO CARRIER