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Power Wireless Networking Science Hardware

Wireless Power Now A Reality 197

slashdottit! tm
CSMastermind writes "CNN is reporting on a breakthrough technology. A startup called Powercast has developed and patented a device, the size of a dime and costing 5$ to make, which allows power to be transmitted wirelessly. The device has already gained FCC approval and the company has inked deals with the likes of Phillips. From the article: 'Powercast says it has signed nondisclosure agreements to develop products with more than 100 companies, including major manufacturers of cell phones, MP3 players, automotive parts, temperature sensors, hearing aids, and medical implants. The last of those alone could be a multibillion-dollar market: Pacemakers, defibrillators, and the like require surgery to replace dead batteries. But with a built-in Powercast receiver, those batteries could last a lifetime. '"
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Wireless Power Now A Reality

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  • dupe? (Score:5, Insightful)

    by Mr. Capris ( 839522 ) <tobeycapris&gmail,com> on Sunday April 01, 2007 @01:24AM (#18563907)
    IIRC, there was something like this last year....

    Although i could be thinking of the "wireless extension cords" on ThinkGeek...
    • Re: (Score:3, Informative)

      by SEMW ( 967629 )
      This isn't an april fools joke -- although I'm pretty sure it's a dupe nevertheless, and it's also not very interesting. It doesn't even use induction; it's just transmitting power by E-M waves -- here, radio waves; which certainly works -- crystal radios anyone? RFID chips? -- but is VERY inefficient (especially if you want to convert the radio waves back into electricity, rather than, say sound, as a crystal radio does), and can't be used to transmit more than tiny amounts of power. The only thing new
      • Re:dupe? (Score:5, Informative)

        by The Great Pretender ( 975978 ) on Sunday April 01, 2007 @02:04AM (#18564157)
        There was a report on cnet Jan 7 this year. They unveiled the concept and Philips interest at CES 2007 l []
      • by naoursla ( 99850 )
        What do you think induction is based on if not radio waves?
        • Re: (Score:3, Informative)

          by SEMW ( 967629 )

          What do you think induction is based on if not radio waves?
          An alternating magnetic field, which induces a current. This is NOT the same as electromagnetic radiation, of which radio waves are an example.
          • Re:dupe? (Score:5, Informative)

            by naoursla ( 99850 ) on Sunday April 01, 2007 @02:59AM (#18564429) Homepage Journal
            Radio waves are alternating magnetic fields. The faster the field is alternated the more power it has and the further it travels. Go study how an AM transmitter and receiver works. Most AM antennas are simple inductive coils that pick up a modulations in a magnetic field. Building an AM transmitter is one of the simplest projects you can do (and was a project in my first circuits class). All you do is make a periodic signal and bound the amplitude by some input (like from a microphone). Then you run it through a coil of wire to create the alternate magnetic field. The magnetic field then hits the coil in the antenna of the receiver and induces a current. The current passes over a resistor and you measure the voltage level. You run that voltage level through a band pass filter and then through an amplifier and then to a speaker and voila! you get to hear whatever the microphone on the other end is picking up.
            • Re: (Score:2, Informative)

              Radio waves are alternating magnetic fields.

              That's wrong, they are alternating magnetic AND electric fields, orthogonal to each other. That's what electromagnetic radiation means, indeed.

            • Such technologies have been in use for years, for pacemakers, cochlear implants, and other embedded medical devices. They're not hard to make. Of course, if you have such a device implanted, you *cannot* be safely put in an MRI. The shifting magnetic fields will couple to the embedded loops in the device and drive masses of current through it, destroying it and potentially overheating it. If the coupling is strong enough, such as if a magnet is in the device, then the MRI will couple *mechanically* to the d
            • Time to hit the books again. There are two ways to couple power: static field coupling (i.e. like a transformer) and propagating-wave coupling (i.e. radio.)

              A static field may be purely E or purely H, but it doesn't propagate. Transformers are the simplest example. There's a magnetic field generated by one inductor that's coupled to another inductor through a magnetic (H) field. There's no electric field to speak of. That field won't move ... at all. The physics says it can't.

              To get a propagating
            • by anethema ( 99553 )
              Radio waves are alternating magnetic fields. The faster the field is alternated the more power it has and the further it travels.

              Actually this is wrong. At least on the 'further it travels' aspect.

              If you look up the calculation on loss as a electromagnetic wave travels, one of the components is 20log(f), f being the frequency. So as f goes up, so does loss in the same amount of distance.

              Here is the full equation shamelessly taken from wikipedia.

              FreeSpaceLoss (dB) = 36.6 dB + 20*log[frequency(MHz)] + 20*log[
              • Radio waves are alternating magnetic fields. The faster the field is alternated the more power it has and the further it travels.

                Actually this is wrong. At least on the 'further it travels' aspect.

                Also the "just magnetic field" part, (as explained by another poster above.)

                And also the "faster the stronger" part.

                The rate of alternation is just the frequency of the wave, and has nothing to do with power.

                The power for a given waveform and polarization is proportional to the square of the peak field strength.
            • At shorter wavelengths, a coil of wire is not needed. You can do a lot at the molecular level. A common wireless power transmitter in my area is called a light bulb. A reciever is call a solar cell. The advantage of using this technology is once in a while you don't have to provide the power to make the light so you get free power. Unfortunately, this seems to work only during the daytime.
      • Re: (Score:3, Insightful)

        by evilviper ( 135110 )

        but is VERY inefficient

        It would certainly be idiotic for things like cellphones. However, I could see the technology being incredibly popular for medical implants.

        Instead of a $50,000 surgery to replace a battery, you put a little charged coil against your body for a few hours every few months to charge the battery.
    • Re:dupe? (Score:5, Funny)

      by saskboy ( 600063 ) on Sunday April 01, 2007 @02:08AM (#18564173) Homepage Journal
      My calculator has had wireless power - from light, for decades. This is such old news ;-)
      • Re: (Score:2, Funny)

        by RedElf ( 249078 )
        Decades? You thieving little techno-whore, this technology has been in my spaceship since long before the Earth came about.
  • Wow, are you guys not even trying? I mean, that's just freakin obvious!
  • See you Monday (Score:1, Insightful)

    by mh101 ( 620659 )
    Well, no point in me returning to Slashdot until Monday... hopefully nothing truly interesting and non-April-Fool's related gets posted until then.

    • At least it's a Sunday and I'm not at work trying to kill time. See you Monday, Slashdot.

    • Re: (Score:2, Funny)

      by l0cust ( 992700 )
      What would be funny if this story was correct for a change. Then we will win and you will lose, We will point and laugh and You will cry!

      Yeah I need some coffee now.
    • babelfish this [] in the meantime, then. Inventors working my themselves discovering amazing things and getting basically fought. I had seen the related video on national tv this ain't an april fool.
    • by AusIV ( 950840 )
      RTFA, it's dated March 30th. Unless they started their April fools joking early, I think this is legit. Plus, I've been seeing stuff similar to this for a year and a half or so, sometimes nowhere close to April fool's day.
  • by smash ( 1351 ) on Sunday April 01, 2007 @01:27AM (#18563941) Homepage Journal
    Tesla [] did this sort of thing prior to 1900...
  • Dupe (Score:1, Insightful)

    by splodger75 ( 961977 )
  • Not april fools (Score:5, Informative)

    by benh57 ( 525452 ) <bhines.alumni@ucsd@edu> on Sunday April 01, 2007 @01:30AM (#18563965) Homepage
    This one's real kids.

    Write-up from Jan. []

    Official Site []

  • by oDDmON oUT ( 231200 ) on Sunday April 01, 2007 @01:31AM (#18563979)
    "Frank! I *told* you you should get the cable backup, but noooo....they'd mess up the line of your suit". Shakes head dolefully and flutters hands ineffectually "At least I could have plugged that pacemaker in".
  • by jsm300 ( 669719 ) on Sunday April 01, 2007 @01:37AM (#18564019)
    If this is an April Fools joke then a lot of work went into establishing background for it. According to a CNET article back in January this company (Powercast) attended CES and mentioned Philips as a partner back then. The article referenced here was written on March 30th (although the URL has 04/01 in the name). That article is in complete agreement with the Cnet article. the Powercast website ( was established last October. Then again, Slashdot has a tradition of a bunch of bogus articles on 04/01, but perhaps this isn't one of them.
    • I've got an idea:

      Lets take a ridiculous sounding true story and then wait until April Fools to post it. No one will believe it, but the joke is still on them!
      • Make it one we had as an April fools joke *last* year, then ppl will cry "dupe" too. It's actually really funny if you think about it: the only real story thatll prolly get posted today, it's an (almost) unbelieveable breakthrough that's been made fun of on this day in the past, and everyone will gloss over it as an april fools gag...
  • Well, we know that every energy conversion step wastes some energy. So, at times where several governments are planning to ban incandescent lights, is it wise to go the way of wirelless power, with all the potential waste, just to enable people to have the convenience of charging their laptops without the minor hassle of handling a cable? (PS: Of course, for serious applications like medical implants, I think it's a good idea and worth the waste)
    • So you're trying to compare the efficiency of fluorescent bulbs versus incandescent to ... what? The idea here is mostly to power things that are running on batteries now. Anytime that you can replace batteries with grid power, even at low efficiencies, you're already ahead. And of course, all the devices that are simply impractical if they have to be plugged in or loaded up with bulky batteries.

      Besides, no one ever said that environmentalism and conservation meant that you have to live a shitty life w

  • All hail the power of induction! The same power that lets insane farmers lay down ~2km of copper wire underneath high tension lines to leech ~110V of current will power our PDAs from... a few centimeters away.
    • The same power that lets insane farmers lay down ~2km of copper wire underneath high tension lines to leech ~110V

      I heard of guy who lived next door to an AM radio transmitter. He hooked a wire to the cyclone wire fence around the transmitter, rectified and inverted it and used it to run his house.

      Must have taken a while to find, too.

  • by fermion ( 181285 ) on Sunday April 01, 2007 @01:53AM (#18564095) Homepage Journal
    post a real story on april fools day! We barely expect legitimate stories the rest of the year, much less on April 1. Next thing you know stories will be edited to meet standard English requirements.
    • Re: (Score:3, Funny)

      by smash ( 1351 )
      Dude, this story was posted on april fools day, to fool those who think it was an april fools into posting crap like "april fools" and "slashdot is so not worth reading until monday", etc..

      It's the thinking man's april fools story of the day :D

    • A real April Fool's Day post: "slashdot announced today that they're implementing a heuristic algorithm to detect and screen all duplicate submissions. And they're hiring a proofreader." Hee. It's funny because it's a lie...

  • Without wires, the price of copper will drop. What are all of those copper thieves going to do for money now? Maybe now I'll be able to legally melt all of my pennies again.
  • To recap (Score:5, Funny)

    by slickwillie ( 34689 ) on Sunday April 01, 2007 @02:06AM (#18564167)
    Let's see. We have:

    Power over Ethernet.
    Ethernet over power.

    Now we can have Ethernet over Power over Wireless over Ethernet over Power over ....

      I think we are almost there.
  • Lifetime (Score:5, Funny)

    by evilviper ( 135110 ) on Sunday April 01, 2007 @02:12AM (#18564201) Journal

    Pacemakers, defibrillators, and the like require surgery to replace dead batteries. But with a built-in Powercast receiver, those batteries could last a lifetime.

    The batteries already last a lifetime!

    As in: when they die, you die.
  • I have only read the summary, but I am overjoyed by this fantastic new development! Batteries that could last a lifetime! Yippee! I am fed up with laptop and cellphone batteries losing capacity after a couple of years.
    • Has nothing to do with that. Thats a problem from the technological limitations of the battery cycle lifetimes This technology (like TFA says) allows such things as charging your cell phone while you sit at your desk, while its in your pocket.
  • My toothbrush has been charged wirelessly for years. So, they just cranked up the power? Hmmm
    • My toothbrush has been charged wirelessly for years. So, they just cranked up the power? Hmmm

      not quite. what that kind of wireless charger uses is inductive coupling, using coils and using a magnetic field to induce a current in device's coil.

      this method uses radio waves, which is a more interesting trick and works over a longer range (inductive charging is limited to a few inches at most with reasonably-sized coils).

      still, this isn't delivering an enormous amount of power yet. about enough to drive a cell
    • The Sonicare toothbrush uses induction, not electromagnetic transmission. The little plastic tower on which you set the toothbrush is the primary of a transformer. The secondary of the transformer is in the toothbrush. The primary and secondary must be very close to allow the transfer of power (or the frequency must be high).

      Neither induction or electromagnetic transmission allow the transfer of power over significant distance around people, because of the possibility that humans could be in the way.

  • Umm: Microwave? (Score:3, Informative)

    by Irvu ( 248207 ) on Sunday April 01, 2007 @02:35AM (#18564289)
    Microwave power transmission has been a reality since at least the 60's and is still in use today (just don't get in the way :). See Das Vikipediem [] for more info. I believe also that Nikolai Tesla did some little work in this area again see El Viki []

    Don't get me wrong I applaud any technology the size of a dime that can be made for $5 and transmit power safely for our nifty home devices and pacemakers but, due respect to CNN's science guys I ain't about to go out and buy Powercast's stock just yet. Especially since the most common use of bradcast power (the Radarange) nd medical tech (pacemakers) are rumoured not to get along together. []
  • But is it worth all the shocks?
  • by jimmydevice ( 699057 ) on Sunday April 01, 2007 @02:38AM (#18564309)
    I would like to invest in your development of this super power source. This requires a private arrangement. My company, IM-krook LTD has reviewed your patent and find it valid. IM-krok will be willing to fund the progjct for $40,000,000 Million dollars. USA. We will need a bank deposit number and credit card numbers with pins to verify your sincerity^w^w^w^w. You will receive these funds underlegal claims; all legal documents will be carefully worked out to ensure a risky free transfer. I am willing to pay a generous management fee as well as appreciation as soon as this transaction is financialy sponcored & completed by you. I have all the details. All correspondences will be via email, for now. The funds in question are quite large. I will expect a straight answer from you. Yes or no. If yes, Kindly furnish me with your personal information which must includ your direct cell phone and fax number, your address and company name, then lets work out the modalities from there Thanks and God bless you, Mr. David Yong. Phone: (44) 7024097815
  • But... the microwave power plant shouldn't be available until around 2028; that's what the strategy guide said!
  • by CrazyJim1 ( 809850 ) on Sunday April 01, 2007 @03:08AM (#18564467) Journal
    "If you had asked me seven months ago if this was possible, I would have said, 'Are you dreaming? Have you been smoking something?'" says Govi Rao

    I thought this was common knowledge 10 years ago, just not the engineering side.
    • The basic physics was common knowledge since the first germanium crystal radios, and since Tesla's work. The engineering side of a cheap and efficient receiver has always been difficult. There's a major mistake in the little blurb in The Fine Article, though. The reflections off the wall do not change the frequencies of the transmitted waves: they do smear the shape of the waves, and mess up the phases of the components, and make it more difficult to tune the receiver to recover the power efficiently. 70%
  • Haha! Made you look. April fools. Buh-bye. See you Tuesday. By then, all this stupid crap should have worked its way off the front page.

  • Thought it was an April's Fool.
    The fools sit - as so often - in the USPTO. They have granted, I repeat *granted* the following claim 1 of US7,027,311:

    "1. An apparatus for a wireless power supply comprising: means for receiving a range of RF radiation across a collection of frequencies; and means for converting the RF radiation across the collection of frequencies into DC, the converting means includes an absorbing mechanism which is resonant for a desired band of RF spectrum." []
  • NOT april fools. (Score:4, Informative)

    by Devistater ( 593822 ) * <> on Sunday April 01, 2007 @04:09AM (#18564783)
    Official webpage: [] Also, they were picked "Best Emerging Technology at CES 2007" Theres other links availible on their webpage (and from google), and NONE of the source articles are dated April 1st.
  • Not an April Fools (Score:4, Interesting)

    by mustafap ( 452510 ) on Sunday April 01, 2007 @04:27AM (#18564889) Homepage

    This has already been reported. There is nothing new here, really: it's just an efficient transformer.

    My concern is just how efficient will it be? We waste huge amounts of energy already with directly coupled chargers that are left plugged in and powered when not in use. This is just a *less* efficient version of the same.

    So, anyone have any figures for efficiencies compared to direct connection chargers?
  • it's Philips (Royal Electronics B.V.) - not Phillips (the screws).
  • Sure you could have a power station that only broadcast radio energy when a suitable device comes in range but even with that I'd guess at least 95% of the power is wasted. That's fine for medical implants and other devices where the wireless power transfer is a necessity rather than an option. But for conventional devices like cell phones and mice and keyboards, your burning a lot of fossil fuel just for a little convenience.
  • On their website [], you can sign up to receive some docs by email. The "datasheet" devotes one page each to the transmitter and receiver chips.

    The transmitter is a 12-pin package; mostly ground pins, plus serial clock/data, vdd, and rf out. It operates on 5V.

    WPT series Powercaster(TM) modules are programmable frequency
    sources for use in RF power harvesting applications. The modules
    encapsulate proprietary algorithms which extend the effective
    range of power transmission without increasing average power. Numero

  • Energy waster (Score:3, Insightful)

    by FridayBob ( 619244 ) on Sunday April 01, 2007 @07:28AM (#18565643) Homepage
    Up to 70% efficient means at least a 30% energy loss; when recharging millions of little devices, that all adds up to a lot of waste. In virtually all cases, recharging the old fashioned way is likely to be better for the environment. However, it looks set to become so popular, that I wonder if we'll be given the choice. I hate wires too, and the convenience of this invention is obvious, but it also has a down side.
  • A slight problem with wireless power is illustrated here: []
  • by kurt555gs ( 309278 ) <kurt555gs@ov i . c om> on Sunday April 01, 2007 @09:37AM (#18566243) Homepage
    This is an example of how broken our patent system is. Prior art goes back to Tesla, where over 100 years ago he transmitted 100 Watts of AC power 100 miles and recovered 97 Watts of energy. Secondly all RFID chips use this to power themselves. There is NOTHING innovative or novel in this device and it never ever should have been granted a patent.

    I really wonder how far our world could have advanced in the last 200 years if patents either didn't exist or were structured in such a way that they were much more limited in scope.

    Another bad day for us for 17 years.

  • All April fools jokes aside, Nikola Tesla DID do this, decades ago.

    Please at least pick someting that isnt real if you are going to do a April 1 joke...
  • The simple fact is that if a capacitor combined with this tech can be created cheaply, then it will replace most batteries overnight. Basically, nobody likes changing batteries. But if I can buy batteries for my kid's toys and never have to take them out again until the toy ends (at which point, I get to re-use the "battery"), then I am all over it. And so will other parents.
  • As a few people have pointed out, using this device will waste an additional 30%+ of the energy used to recharge batteries.

    They will have been working on this product for several years and must have been agonising over the attention that has been focused on global warming and energy efficiency in the last year or so.

    To combat this they have put together a hilarious white paper on the environmental benefits which you can request from their website. My favourite is the solar panel one:

    An Ecologically Friendly

Nondeterminism means never having to say you are wrong.