Slashdot Mirror

← Back to Stories (view on slashdot.org)

What is the Future of Wireless Power?

Posted by CmdrTaco on from the this-is-gonna-burn-my-crotch-isn't-it dept.

mfbatzap writes "According to Firdooze, we have seen various devices that can free ourselves from wires at CES 2008. The manufactures, Wildcharge, Powercast and Fulton Innovation, came out with two different methods of transmitting power from source to the devices. Wildcharge and Fulton banked on magnetic coupling while Powercast decided to go with RF (Radio Frequency). So which technology will eventually prevail to be the future of wireless power? Or will the technological setbacks from transferring power wirelessly make it unrealistic to accomplish a wire-free world?"

12 of 178 comments (clear)

  1. Re:Woah by somersault · · Score: 5, Insightful

    For the types of application this is meant for, I think the old option would be a power cable. Unless you want to run your TV and computers from a few truck sized batteries. Seriously, when they brought out laptops did you say "JUST USE A DESKTOP!"? When they invented the telephone would you have said "JUST GO FOR A VISIT!". When people are walking into hospital do you should "JUST DIE ALREADY!"?

    --
    which is totally what she said
  2. I say neither, you say neither by Ancient_Hacker · · Score: 5, Insightful
    Wireless power is not going to happen.

    Shooting photons across a room to deliver significant power just ain't gonna be practical. If you use an omnidirectional antenna, the losses will be huge. If you instead have like a parabolic dish that tracks the receiver, the losses will be lower, but what happens to kitty or your eyeballs if they get in the way? Cooking your eyeballs to a nice firm egg-white consistency is not going to fly.

    Magnetic fields are dipole fields, that means the little wavy lines leaving the North pole want to curl back as quicly as possible to the South pole. Which means they have very little extent in space. The strength drops off as the CUBE of the distance, so any significant distance is a no-go.

    1. Re:I say neither, you say neither by MBCook · · Score: 3, Insightful

      That's not wireless (RF) like he's talking about, that's inductive. It works on the same principal as a transformer. It only works under VERY short distances. If you lift your toothbrush out of it's charger by a 1/2", it probably won't work anymore.

      An RF system would let you use the toothbrush without having it charged in a station. You could hang it from the ceiling with a piece of twine, turn it on, and let it run until something physically wears out.

      I agree with the GPP, it's impractical. Inductive coupling (which I think is the same as magnetic being discussed) makes far more sense.

      --
      Comment forecast: Bits of genius surrounded by a sea of mediocrity.
  3. Re:Out of curiousity... by mblase · · Score: 5, Insightful

    Off my limited knowledge, it would seem to be akin to one of the problems with biofuels...they currently take more energy to produce than they store.

    If I remember my Second Law of Thermodynamics correctly, this is true in any case.

    (Yes, I know what you meant.)

  4. Tough...No Easy Answer by BoRegardless · · Score: 2, Insightful

    There is s vast difference between a universal wireless charging "surface" or "plate" where your electronics go at night versus recharging at a distance of 10 feet.

    Then there is also a difference between the "idle" power loss versus "zero" while turned OFF & of the transmitters efficiency in getting power to a remoted device. I could imagine only 25% or less of the transmitter's input getting to the remote device.

    Time matters. Batteries are going to get better quicker if A123Systems & others are right, meaning charging with a standard cord may be the cheapest & best method giving a 5-10 minute recharge, as opposed to overnight.

    Ain't going to be easy. Lots of VC money is going to be burned up. The good news is the U.S. government is not picking and funding a single winner, as they tend to do when they back a "bill".

  5. Wireless power? by Gavin+Rogers · · Score: 3, Insightful

    Already invented. Next!

    http://en.wikipedia.org/wiki/Tesla_Coil

    1. Re:Wireless power? by thatskinnyguy · · Score: 3, Insightful

      Even better than that, Tesla was able to power stuff at great distances. He was doing stuff like this as early as 1891. Really people ought to start giving Tesla his due and stop claiming his concepts for themselves. More on his wireless power experiments here.

      --
      The game.
    2. Re:Wireless power? by aix+tom · · Score: 2, Insightful

      Yep. And then Westinghouse got wind of it, and thought "Wireless energy? How the hell will we be able to bill people for using it?" and axed the project.

      Which will still be a problem today, even when they overcome the technical problems.

  6. I like wires! by jabjoe · · Score: 2, Insightful

    I want to see what is connected to what in a nice clear visual way, i.e wires. I want soild connections, i.e. wires. I want secure connections I could see no one else is using, i.e wires.

  7. Misleading thoughts... by Velorium · · Score: 2, Insightful

    The focus shouldn't be on "wireless" power per say, but in general just absorbtion of energy which doesn't require a tether, AKA solar & etc. to an extent. RF may be possible but I'd be damn weary if there weren't some massive long term safety tests first.

  8. Re:is there a way by Sarutobi · · Score: 3, Insightful

    As long as we're getting in the scientifically correct... Frequency does matter. If the frequency is too high, the dipole won't be able to follow and you'll see other phenomena pop up. That is, for instance, why water is blue. The frequency of the electrons around the dipole allow them to absorb a bit of red light. If you go even higher, it will stop interacting altogether. If you go too low, the energy transfer will be hindered.

    --
    Think about this: Axe and Dove are actually the same company. Vincent L.B.
  9. Re:Great, more incompatible standards by vanyel · · Score: 2, Insightful

    In a sense, we've standardized our "wired power connectors" with the 120V (US) outlets. The devices haven't standardized their power inlets though, so we have a bazillion adapters.

    That would be the advantage of the rf method though: even if there were multiple incompatible formats, at least the device could pick up whatever it needed. You'd still have to carry the transmitters around unless they became ubiquitous though. That would be nice, but seems like the long shot, both for health concerns (valid or not) and efficiency reasons.

    The most likely "good" option would be a single inductive standard. You carry around a single pad that everything can sit on.

    With at least two different inductive systems going at it, I'm not holding my breath, but if there are only two of them, neither of which is a Big Name, there's at least a chance...