What is the Future of Wireless Power?

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?"

Comments

Re:Woah

[somersault]

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!"?

I say neither, you say neither

[Ancient_Hacker]

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.

Re:I say neither, you say neither

[MBCook]

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.

Re:Out of curiousity...

[mblase]

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.)

Wireless power?

[Gavin Rogers]

Already invented. Next!

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

Re:Wireless power?

[thatskinnyguy]

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.

Re:is there a way

[Sarutobi]

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.