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Cell Phones Powered By Conversations

Posted by CmdrTaco on from the yakkity-yak dept.

disco_tracy sent in a story about some fancy new power technology designed to tap energy from sound waves. Although the cell phone concept grabs the headline, they also talk about harvesting noise from traffic.

28 of 119 comments (clear)

  1. Infinite power by grapeape · · Score: 4, Funny

    Geez if I could hook up a storage battery and wire it to my wife I could go off grid.

    1. Re:Infinite power by $RANDOMLUSER · · Score: 2, Informative

      Congress could power the whole country.

      --
      No folly is more costly than the folly of intolerant idealism. - Winston Churchill
    2. Re:Infinite power by Lotana · · Score: 2, Insightful

      With our state of infrastructure, that much supply would overload the whole thing.

    3. Re:Infinite power by MobileTatsu-NJG · · Score: 4, Funny

      Geez if I could hook up a storage battery and wire it to my wife I could go off grid.

      From what I understand about your wife, she'd use it up again before sunrise.

      --

      "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

  2. I could go one better by T+Murphy · · Score: 2, Funny

    Just make a phone that, while making a call, recharges its battery from the motion of the car. You've got a lot more energy to work with there than just sound energy, especially if you can derive energy from sudden stops.

    --
    My webcomic
  3. Re:first post by ohiovr · · Score: 2, Funny

    If only data centers could be powered by forum posts like this. Theres an unlimited supply to draw from.

  4. Great by EkriirkE · · Score: 4, Funny

    SORRY I'M YELLING, MY BATTERY IS LOW!!!

    (off-topic lowercase to side-step /. yelling filters here)

    --
    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
    1. Re:Great by Anne_Nonymous · · Score: 3, Funny

      Could you speak up a bit? My battery is low too.

    2. Re:Great by hack++slash · · Score: 2, Funny

      PARDON?

      --
      To do something right, you often have to roll up your sleeves and get busy.
  5. Bogus by dtmos · · Score: 5, Informative

    This is a bogus story that wanders around every now and then. Cell phones require hundreds of milliwatts of transmit power, an amount of power far beyond what the human voice can achieve -- even at 100% conversion efficiency.

    1. Re:Bogus by Charliemopps · · Score: 2, Interesting

      You're completely misunderstanding how it works. A. The human voice produces a hell of a lot more power than a cellphone, you can disagree if you want but it's not even relevant because: B. Ambient noise. It's not just you powering the device, it's everything that makes noise around you. and then, don't forget: C. Energy over time. It's charging it all day long, even when you're not on the phone. They aren't talking about you literally powering the phone as you talk. They are talking about a device on the phone that helps recharge the battery as you talk. Just like breaks on electric cars recovering the breaking energy aren't going to power the car entirely, but they certainly will help make the battery last longer.

    2. Re:Bogus by blueg3 · · Score: 5, Informative

      The human voice produces a hell of a lot more power than a cellphone, you can disagree if you want

      Well, a human shouting is about 1 mW. A cell phone's antenna outputs in the ballpark of 250 mW.

      Some quick back-of-the-envelope calculations suggest that if the entire area of a cell phone could pick up sound energy, the ambient sound level was at the pain threshold of 120 dB (1 W/m^w), and it achieved 100% energy conversion, this would generate about 15 mW. For just the 250 mW antenna, this means about 90 minutes of talk time per 24 hours exposure.

      120 dB is very loud, and a far cry from how much sound a phone would normally be exposed to. Note that sound is measured on a logarithmic scale. If the phone was constantly exposed to 60 dB of sound, then it'd only generate 15 nanowatts.

    3. Re:Bogus by complete+loony · · Score: 2, Interesting

      But could you use this trickle of energy to reduce or eliminate the battery drain when the phone is idle?

      --
      09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
    4. Re:Bogus by blueg3 · · Score: 2, Informative

      Not really. All of my estimates are very high (conversion of 100%, entire phone is covered in the sound-converting material, etc.), but the ambient noise level is the problem. In a crowded place like a restaurant, you're talking about maybe 60 dB of sound. An entire day's exposure to 60 dB of sound would get you less than 1 microwatt-hour. That's a uselessly tiny fraction of a battery's storage.

  6. Conservation of Energy by __aajfby9338 · · Score: 4, Insightful

    If only we could harvest energy from articles about operating multi-watt devices from nanowatt energy sources, all of the world's energy problems would be solved.

    1. Re:Conservation of Energy by Jedi+Alec · · Score: 2, Funny

      I suppose we could go around wrapping dead scientists in copper wire...?

      Now if you'll excuse me, I'm off to patent the magnetic coffin.

      --

      People replying to my sig annoy me. That's why I change it all the time.
  7. People use cell phones for conversations? by Haeleth · · Score: 2, Insightful

    Cell phones are for apps, or texting. I didn't realise anyone used them to talk any more, except for members of an evil secret society dedicated to inflicting pain on users of public transport.

  8. Hams have done it ... by EABinGA · · Score: 5, Interesting

    A ham operator has built a voice powered radio and has made several long distance contacts with it.

    Details are here

  9. This is a terrible idea by iONiUM · · Score: 2, Funny

    So those people on their phones 24/7 (I realize that's a bit of a 90s comment right there, but you know who I mean) will only be rewarded with MORE battery power? They already won't shut up. Damn it.

  10. It already does by wisnoskij · · Score: 2, Informative

    The phone already taps the energy of sound, if their was no energy in the sound then the microphone would not be able to pick up the sound waves and send the information on.

    But even assuming that they can get the device to convert the power to small enough it does not matter, you would need a wide receiver, as the energy dissipates in all directions at a squared rate.
    and I would think that even if you converted all the power it would still not even be close to enough.
    think about it, you are basically saying the energy taken from a person speaking normally could be used for the same voice to be heard miles away, does not sound like it follows the laws of conservation of energy unless you think that it will be operating at 100% efficiency.

    --
    Troll is not a replacement for I disagree.
  11. Re:Traffic solution? by Lotana · · Score: 4, Informative

    ...and remember that things powered by the car driving over a power capturing device is stealing gas from your tank indirectly.

    Stealing? Are you trying to troll by attempting to get people outraged that the device powers from the sound generated due to inefficiency of your vehicle?

    It is technically true, the energy of the sound does comes from your fuel tank. But remember that your car would still be expanding just as much energy on generating the noise whether or not there is any sound-gathering device around. Driving on the country road in the middle of nowhere will not increase your fuel efficiency.

    Really the term "stealing" is completely invalid in this case. Now if the headline was about some fancy road surface that converted traction into energy then you would be absolutely correct, because it would adversely affect the performance of your vehicle, thus increasing its energy expenditure, thus stealing from your fuel tank.

  12. finally a device... by Odinlake · · Score: 3, Funny

    finally a device that actually might start working again when you yell at it.

  13. Really? by pookemon · · Score: 3, Funny

    From TFA - "Just as speakers transform electric signals into sound, the opposite process -- of turning sound into a source of electrical power -- is possible"

    I never would have guessed that. Maybe now they can make something capable of turning sound into electrical impulses. I will patent that idea I think - and call it an anti-speaker. Or an audioelectictransmogrifier for short.

    --
    dnuof eruc rof aixelsid
  14. From the Article by PiAndWhippedCream · · Score: 3, Informative

    The sound waves produced a mild electrical current of about 50 millivolts. The average cell phone requires a few volts to operate, several times the power this technology can currently produce.

    Wrong, so very wrong. Millivolts is not a unit of current, and volts is no unit of power. Nor is power current. I've seen journalists not understanding electrical units before, but never have I seen something quite so wrong as this.

    1. Re:From the Article by cosm · · Score: 2, Funny

      Shhhh. Your going to confuse average joe-sixpack even more. The editors must have assumed that their tripe would pass the standard jargon filter. Does anybody have a regex for finding all the jargon in some text, so you can subsequently replace it with stuff this guys says?

      I am sure six-pack wouldn't notice.

      --
      'We are trying to prove ourselves wrong as quickly as possible, because only in that way can we find progress.' RPF
  15. Sound-Powered Telephone.... by Anonymous Coward · · Score: 2, Informative

    Hmm.. Sounds a lot like the "Sound-powered Telephone" that's been in use with the US Navy (and probably many other navys) for over 6 decades....

    http://en.wikipedia.org/wiki/Sound-powered_telephone

  16. Re:Traffic solution? by sjames · · Score: 2, Insightful

    Many would consider it to be recovering some bit of the peace and quiet the passing cars despoil.

  17. Ridiculous times 100,000 by Ancient_Hacker · · Score: 2, Insightful

    Ridiculous. Phones need about a watt. If you SHOUT into a microphone, you will maybe generate 50 millivolts across 600 ohms, or (E^2/R) about FIVE BLEEPIN MICROWATTS.

    We're a good five powers of ten below what is needed.

    Doesn't anybody do math anymore?