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What is the Future of Wireless Power?

CmdrTaco posted more than 6 years ago | from the this-is-gonna-burn-my-crotch-isn't-it dept.

Power 178

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?"

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I for one hail our new glowing overlords (4, Funny)

debatem1 (1087307) | more than 6 years ago | (#21985468)

I have to wonder whether this announcement and the glowing pigs announcement are just coincidental...

Woah (0, Troll)

ilovegeorgebush (923173) | more than 6 years ago | (#21985482)


Re:Woah (5, Insightful)

somersault (912633) | more than 6 years ago | (#21985622)

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!"?

Re:Woah (2, Funny)

ohtani (154270) | more than 6 years ago | (#21985874)

Should I use batteries to charge my batteries?

First post!!!! (-1, Troll)

snotclot (836055) | more than 6 years ago | (#21985488)

First post!!!!!!!!

Re:First post!!!! (0, Offtopic)

thegermanpolice (1194811) | more than 6 years ago | (#21985558)

First Post...

+++ ERROR Insert cheese +++

Redo from start...

Wireless Everything (5, Funny)

ShawnCplus (1083617) | more than 6 years ago | (#21985512)

Well my laptop has wireless internet and a wireless mouse, why not wireless power? I'd gladly accept a benign tumor or two if I could get more than 3 hours out of my battery.

Re:Wireless Everything (4, Funny)

ByOhTek (1181381) | more than 6 years ago | (#21985572)

well, I experimented with this. While the tumors were benign to me, after the third or fourth time I woke up to find one gnawing on the limb of a small child it apparantly captured/ate/killed, I decided it was time to have it removed. Apparantly three doctors were lost during the procedure.

Re:Wireless Everything (0)

Anonymous Coward | more than 6 years ago | (#21986140)

This will be a blessing for the cell phone makers. We're not responsible for your tumor because you have a powerless laptop. Prove it's not Dell's fault

Re:Wireless Everything (1)

Anynomous Coward (841063) | more than 6 years ago | (#21986540)

Speaking of tumors [] ...

is there a way (3, Interesting)

JeanBaptiste (537955) | more than 6 years ago | (#21985522)

to transfer power wirelessly without cooking whatever happens to pass inbetween the sender and receiver?

Re:is there a way (1)

gardyloo (512791) | more than 6 years ago | (#21986098)

Probably. Just make damned sure that the transmitter produces frequencies which couple strongly only to the receiver (very small bandwidth). Things which don't resonate at those frequencies will be essentially transparent to the signals. I suggest 2.45 GHz!

Re:is there a way (1)

Atti K. (1169503) | more than 6 years ago | (#21986868)

Power over WiFi FTW!

Re:is there a way (2, Interesting)

jdray (645332) | more than 6 years ago | (#21986114)

From what I understand, it depends on the frequency. For instance, a microwave oven operates at whatever frequency best excites a water molecule, which leads to cooking by making the water in everything hot.

There was a long-running experiment in California back in the seventies or so that transmitted kilowatts of power over a few kilometers. They were doing the test as a lead-in experiment to figure out whether or not satellite-based power generation and transmission was feasible.

I'm not confident that we know about the long term health effects of exposure to various magnetic fields. Back in the early nineties there was a discovery that sitting in front of a monitor for hours on end was causing health problems due to "ELF" (extremely low frequency) radiation. Monitor manufacturers jumped on re-tooling and shielding their CRTs to avoid the problem, and eventually all CRTs complied with a standard ("ELF-II" IIRC) that was deemed safe. I don't believe LCDs have the same issue.

Re:is there a way (1)

mfbatzap (1216220) | more than 6 years ago | (#21986542)

Those KM transmission used huge antennas and high frequencies which i doubt is feasible for daily application.

Re:is there a way (5, Interesting)

Otto (17870) | more than 6 years ago | (#21986722)

From what I understand, it depends on the frequency. For instance, a microwave oven operates at whatever frequency best excites a water molecule, which leads to cooking by making the water in everything hot.
That is incorrect, but you're forgiven because it is a common misconception that's even in a few encyclopedia's and such.

Microwaves work by producing an alternative electric field (using non-ionizing microwave radiation) that acts on molecules which have electric dipoles. Water is one of those, but so are many others, including fats and such. The process is called Dielectric Heating.

Basically, the molecule being heated is a dipole. It has a positive charge at one end, and a negative charge at the other. In an alternating electric field, it rotates as it tries to align itself with the field. This causes motion, which translates to heat. The heat spreads as the molecules hit other molecules and transfer the energy to them. Now, this process works really good on water because water is a very strong dipole, but it does not operate solely on water, and it doesn't have anything to do with water in particular.

See, the frequency doesn't actually have much to do with it. Normal kitchen microwaves operate at 2.4 Ghz or close to that. Industrial microwave devices tend to work at 915 Mhz. Also, if the frequency had something to do with it, then 2.4 Ghz would be the wrong one. The resonant frequency for water is somewhere in the 20 gigahertz range. The only reason 2.4 Ghz is used for microwaves is that it's a free bands of frequency (ISM frequency bands) that can be used worldwide.

So, there you go. Now you know.

Re:is there a way (1)

Otto (17870) | more than 6 years ago | (#21986802)

Typo correction: "alternative" should be "alternating".

Re:is there a way (3, Insightful)

Sarutobi (1135167) | more than 6 years ago | (#21987484)

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.

Re:is there a way (1)

Bill, Shooter of Bul (629286) | more than 6 years ago | (#21986184)

sure power can be sent wirelessly a number of different ways, with outcomes other than cooking
  • Sound waves carry energy, result: deafness
  • Visible Light waves carry energy, result: blindness
  • Positron beams waves carry energy, result: random explosions/ unexplained disappearance of electrons

Re:is there a way (1)

Stooshie (993666) | more than 6 years ago | (#21986202)

... without cooking whatever happens to pass inbetween ...

Don't worry. If you wear a foil hat you will be protected!

Re:is there a way (1)

contrapunctus (907549) | more than 6 years ago | (#21986648)

And an apron.

Re:is there a way (1)

grumpyman (849537) | more than 6 years ago | (#21986824)

That's right, soon you can place your tv dinner between your monitor and the no-battery wireless keyboard, surfing the web and see the meal cook right in front of you :)

Re:is there a way (1)

Atti K. (1169503) | more than 6 years ago | (#21987056)

And your neighbour can steal electricity from you, just like they can steal your open WiFi. No thanks, until they put some serious security on it. How about WPPA (Wireless Power Protected Access) ?

Out of curiousity... (5, Interesting)

Krinsath (1048838) | more than 6 years ago | (#21985588)

Does anyone know how much power is "wasted" (if any) due to using wireless methods versus wired connections?

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. So will using this technology to charge a device result in taking two or three times more energy to transmit the same amount of power to the device, or is there no discernible difference between wireless and wired?

Just wondering is all...

Re:Out of curiousity... (5, Insightful)

mblase (200735) | more than 6 years ago | (#21985694)

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.)

oblig. (1)

morgan_greywolf (835522) | more than 6 years ago | (#21986406)

HOMER: That's right, Lisa. In THIS house, we OBEY the Laws of Thermodynamics!

Re:Out of curiousity... (4, Informative)

tjstork (137384) | more than 6 years ago | (#21985760)

All fuels take more energy to produce... in a sense, our present fossil fuel predicament is because we are using stored energy from the sun over millions of years. That we can even think about creating biofuels or really, any sort of fuel, efficiently, says a lot for how far the technology has come. But we'll never be able to just "create" a fuel, and the world's going to have to accept that.

Re:Out of curiousity... (1)

timeOday (582209) | more than 6 years ago | (#21986506)

we'll never be able to just "create" a fuel
Nuclear does "create" energy (unless, I suppose, you think of mass as energy). Granted, that energy is still not coming from nowhere, but when you get c^2 (the speed of light, squared) working in your favor, you're doing pretty darn well for yourself. I realize nuclear is still very hampered by practical issues, and I'm not particularly taking a stand for nuclear power over more dissipated forms (solar, biofuels)... but when you step back and think about releasing that much energy from such a small package, it almost seems miraculous.

Re:Out of curiousity... (1)

TheRaven64 (641858) | more than 6 years ago | (#21987662)

Nuclear does "create" energy (unless, I suppose, you think of mass as energy).
This is true of fusion, but fission is solar energy in the same sense that fossil fuels are. The energy was put in to the heavier-than-iron elements by fusion reactions in stars a few billion years ago.

Re:Out of curiousity... (3, Interesting)

snowraver1 (1052510) | more than 6 years ago | (#21986678)

200 years ago people would never fly.
150 years ago it was impossible to talk to someone in another town
125 years ago it was impossible to own a car
50 years ago it was impossible to own a computer (except for banks, schools, and gov't)

You never know what the future might hold. Cold Fusion might prove to be possible. Zero point energy might be proved and harnessed. Maybe someone will figure out a way to take the heat out of the atmosphere and make electricity from that.

My point is, and I do have one, that nothing is impossible. There is more that we don't know then we know... Chew on that.

Re:Out of curiousity... (3, Informative)

MBCook (132727) | more than 6 years ago | (#21985770)

I'd think you'd have problems with RF, it'd be easy to waste power that way. The magnetic people mentioned in the article say they've hit 98.5%, which is great.

Re:Out of curiousity... (4, Interesting)

Abeydoun (1096003) | more than 6 years ago | (#21985788)

Here's the Wiki [] I found on general wireless energy transmission.

From the wiki article

"WiPower [1] technology is a very recent example of inductive charging technology. The charging pad allow users to charge multiple electronic devices that are placed on its surface. It is insensitive to the position or orientation of the devices under charge. Unlike most inductive charging systems, the WiPower system uses air-core technology which allows the system to be integrated into very small electronic devices. The efficiency of the system actually exceeds many corded chargers which have a median efficiency of 57%."

I say neither, you say neither (5, Insightful)

Ancient_Hacker (751168) | more than 6 years ago | (#21985644)

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 (1)

purpledinoz (573045) | more than 6 years ago | (#21985720)

Maybe this is a good thing. I don't want my neighbour leeching my wireless internet AND my wireless power! Besides, I think a practical application of this would be as a laptop dock with no electrical connection. Place your laptop on the charging pad, and your laptop will start charging without having to plug in!

Re:I say neither, you say neither (1)

Fred_A (10934) | more than 6 years ago | (#21987276)

Besides, I think a practical application of this would be as a laptop dock with no electrical connection. Place your laptop on the charging pad, and your laptop will start charging without having to plug in!
At least if there's one thing we can be sure of judging from the last century or so of appliances is that each and every gizmo will have its own charging pad which will be absolutely incompatible with any other gadget you own. Those charging pads will also have "wall wart" transformers that only work with the pad they came with.

Ah, progress, it's so exciting !

Re:I say neither, you say neither (2, Interesting)

farkus888 (1103903) | more than 6 years ago | (#21985816)

it may not make a replacement for everything, but unless I am mistaken I have already seen electric toothbrushes that use something similar over very short distances. the advantage is they don't have to insulate any leads or connectors from the water it will inevitably be exposed to. a sealed case is always better than a sealed case with a rubber plug over the one opening where you give it power. range is not an issue because you are still dropping it into a charging dock [sitting it right on the transmitter] when the time comes to charge.

I also think another great idea would be to make the surface of a desk the transmitter, that way anyone can walk up and sit a laptop on it and their batteries never die. it would also have the nifty feature of powering you wireless mouse, or even speakers a monitor and a external keyboard on your desk at home with one power line to the wall.

Re:I say neither, you say neither (3, Insightful)

MBCook (132727) | more than 6 years ago | (#21985928)

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:I say neither, you say neither (0)

Anonymous Coward | more than 6 years ago | (#21986198)

There's a principal in your transformer? How do you feed him? I imagine he must make quite a mess too. Do you have to let him out once in a while to stretch his legs? Either way, it's a funny principle on which to base your transformers.

Re:I say neither, you say neither (1)

FredFredrickson (1177871) | more than 6 years ago | (#21985944)

I also think another great idea would be to make the surface of a desk the transmitter, that way anyone can walk up and sit a laptop on it and their batteries never die. it would also have the nifty feature of powering you wireless mouse, or even speakers a monitor and a external keyboard on your desk at home with one power line to the wall.
But for god's sake, don't touch the desk. *zap*

Re:I say neither, you say neither (1)

Kintanon (65528) | more than 6 years ago | (#21985972)

I swear I saw a proof of concept from a Korean company that was a desk where the surface was made out of some mat material they made. You plugged the desk/mat into the wall then it powered everything you dropped on it. They had a clock, a radio, and a couple of other little things. I would love for all of my peripherals to be charged/powered just by being in contact with my desk. That would be excellent.

Re:I say neither, you say neither (1)

somersault (912633) | more than 6 years ago | (#21987686) [] , I have seen similar things on TV a few years ago. You have disappointed me.. I thought all /.ers with low uids were like technology gods :(

Re:I say neither, you say neither (5, Funny)

Jeff DeMaagd (2015) | more than 6 years ago | (#21985864)

For the reasons you state, I'd put the people demanding wireless power among the people demanding pony-sized unicorns, at least for the forseeable future. I think pony-sized unicorns is more likely given how genetic engineering is going, but then the people that say they want them are going to say they won't pay more than $1500 for those.

Re:I say neither, you say neither (3, Informative)

Lumpy (12016) | more than 6 years ago | (#21986106)

you dont need to shoot it across the room, just charge the device when set on a table. Make ALL your tables charging stations and now you attain the "wireless power" illusion.

I did this way back in the 90's for one of my EE projects. I created a charge mat and charge adapters to make devices charge from the mat. worked great, erased tapes , credit cards, and discs though... All you did was set the device down and it started charging. worked great and could supply 100ma of charge current to 3 devices.

Re:I say neither, you say neither (1)

replicant108 (690832) | more than 6 years ago | (#21986362)

Re:I say neither, you say neither (1)

felipekk (1007591) | more than 6 years ago | (#21987244)

Nowadays people seem to think that any electromagnetic transmission is going too cook your . To cook something (as in heating the water inside that thing) the frequency must be around 2.4GHz.

It might not be as bad as you think, therotically. (2, Interesting)

sectionboy (930605) | more than 6 years ago | (#21987560)

An average laptop consumes about 50 watts. Using the back of a 15" screen as receiver (0.07 m^2), the intensity is about 50 / 0.07 = 714 watt/m^2. As a reference, "a site in Eastern Oregon receives 600 watts per square meter of solar radiation in July". > See, it's just like walking by an unshaded window in a summer's day.

Re:I say neither, you say neither (1)

Toonol (1057698) | more than 6 years ago | (#21987858)

Yeah, those methods seem inevitably lossy to me. But what about lasers? How efficient are they? It seems like a microwave laser would transport energy efficiently... but I don't know how efficient the creation of the maser is in the first place.

Inventions magazine, 1936 (2, Funny)

Anonymous Coward | more than 6 years ago | (#21985662)

Good news everyone!

Radio-Fuel autos may solve gas problem!" []

All you do, you see, is you put this big coil above your car, and several gigawatts RF transmitters embedded in the roadway! Waste heat from the transmitters (and the melted tires, and the roasting humans) can even be used to ensure that ice never accumulates on the road!

No more cords! (1)

Ngarrang (1023425) | more than 6 years ago | (#21985674)

Wireless power certainly should have a future if a single standard was achieved. It would be nice to be able to sit my child's toys near the charging station and have them charge themselves. No more fuss with changing batteries every month. No risk of losing the AC adapter.

And it can certainly be made efficient and safe by using a focus beam to the device being charged. We are surrounded by RF signals everywhere we go. What is one more RF signal?

arcing (1)

192939495969798999 (58312) | more than 6 years ago | (#21985700)

How do you prevent arcing with wireless power? Seems to me that wireless power pretty much means arcing through the air of some kind for any high-power applications... sounds dangerous in the proximity of the broadcast and receiving antennae.

Re:arcing (1)

desenz (687520) | more than 6 years ago | (#21985828)

That isn't a problem if you're using RF or magnetics.

Magnetic is better (1)

MBCook (132727) | more than 6 years ago | (#21985728)

I'm not in the field. I'm not officially qualified to decide. But this is /.

Wireless (RF) worries me. You either have to confine it to a little beam (then why not just set the device down somewhere?) or pump a ton of power into it (most wasted). There are a few limited applications where it might make sense (the Wii, since we already know you'll be standing in front of the TV). I'm also worried about health concerns (really high frequencies can solve this, to a good degree) and interference (this is what I see as the biggest problem).

The idea of just setting a device down and having it charge seems good enough for me. It would work easily for keyboards and mice, cell phones, laptops, monitors, and many other thing. It's more efficient, and as the article mentions they can provide different amounts of power (like 5v to a cell phone and 12v to a hard drive). The guy who wrote the article worries about things like it erasing your credit cards or zapping you if you take a piece of metal near. This is easily solved by adding a tiny RF signal (like RFID) to detect devices. If you only supply power in the vicinity of that signal, then when someone sets a spoon down you won't fry them.

People have been working on this stuff for years. I hope they finally start getting it out there. It would be great to do something like be able to rearrange my desk (2 monitors, mouse, keyboard, laptop, other stuff) without having to bother plugging in or unplugging all those power cables. Add in a wireless version of HDMI or DVI or DisplayPort and all of a sudden things get really easy. But the best part would be being able to just put my phone on the counter (or desk or whatever) at night and have it change without me having to do anything. Very useful. Bigger batteries wouldn't be as important if you could easily charge devices anywhere and everywhere without having to carry and adapter and fumble for a free outlet.

creators' newclear power already here (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#21985754)

no gadgets required. let yOUR conscience be yOUR guide. you can be more helpful than you might have imagined. there are still some choices. if they do not suit you, consider the likely results of continuing to follow the corepirate nazi hypenosys story LIEn, whereas anything of relevance is replaced almost instantly with pr ?firm? scriptdead mindphuking propaganda or 'celebrity' trivia 'foam'. meanwhile; don't forget to get a little more oxygen on yOUR brain, & look up in the sky from time to time, starting early in the day. there's lots going on up there.;_ylt=A0WTcVgednZHP2gB9wms0NUE [];_ylt=A9G_RngbRIVHsYAAfCas0NUE [] []

is it time to get real yet? A LOT of energy is being squandered in attempts to keep US in the dark. in the end (give or take a few 1000 years), the creators will prevail (world without end, etc...), as it has always been. the process of gaining yOUR release from the current hostage situation may not be what you might think it is. butt of course, most of US don't know, or care what a precarious/fatal situation we're in. for example; the insidious attempts by the felonious corepirate nazi execrable to block the suns' light, interfering with a requirement (sunlight) for us to stay healthy/alive. it's likely not good for yOUR health/memories 'else they'd be bragging about it? we're intending for the whoreabully deceptive (they'll do ANYTHING for a bit more monIE/power) felons to give up/fail even further, in attempting to control the 'weather', as well as a # of other things/events. []

dictator style micro management has never worked (for very long). it's an illness. tie that with life0cidal aggression & softwar gangster style bullying, & what do we have? a greed/fear/ego based recipe for disaster. meanwhile, you can help to stop the bleeding (loss of life & limb); []

the bleeding must be stopped before any healing can begin. jailing a couple of corepirate nazi hired goons would send a clear message to the rest of the world from US. any truthful look at the 'scorecard' would reveal that we are a society in decline/deep doo-doo, despite all of the scriptdead pr ?firm? generated drum beating & flag waving propaganda that we are constantly bombarded with. is it time to get real yet? please consider carefully ALL of yOUR other 'options'. the creators will prevail. as it has always been.

corepirate nazi execrable costs outweigh benefits
(Score:-)mynuts won, the king is a fink)
by ourselves on everyday 24/7

as there are no benefits, just more&more death/debt & disruption. fortunately there's an 'army' of light bringers, coming yOUR way. the little ones/innocents must/will be protected. after the big flash, ALL of yOUR imaginary 'borders' may blur a bit? for each of the creators' innocents harmed in any way, there is a debt that must/will be repaid by you/us, as the perpetrators/minions of unprecedented evile, will not be available. 'vote' with (what's left in) yOUR wallet, & by your behaviors. help bring an end to unprecedented evile's manifestation through yOUR owned felonious corepirate nazi glowbull warmongering execrable. some of US should consider ourselves somewhat fortunate to be among those scheduled to survive after the big flash/implementation of the creators' wwwildly popular planet/population rescue initiative/mandate. it's right in the manual, 'world without end', etc.... as we all ?know?, change is inevitable, & denying/ignoring gravity, logic, morality, etc..., is only possible, on a temporary basis. concern about the course of events that will occur should the life0cidal execrable fail to be intervened upon is in order. 'do not be dismayed' (also from the manual). however, it's ok/recommended, to not attempt to live under/accept, fauxking nazi felon greed/fear/ego based pr ?firm? scriptdead mindphuking hypenosys.

consult with/trust in yOUR creators. providing more than enough of everything for everyone (without any distracting/spiritdead personal gain motives), whilst badtolling unprecedented evile, using an unlimited supply of newclear power, since/until forever. see you there?

"If my people, which are called by my name, shall humble themselves, and pray, and seek my face, and turn from their wicked ways; then will I hear from heaven, and will forgive their sin, and will heal their land."

meanwhile, the life0cidal philistines continue on their path of death, debt, & disruption for most of US. gov. bush denies health care for the little ones; []

whilst demanding/extorting billions to paint more targets on the bigger kids; []

& pretending that it isn't happening here; []
all is not lost/forgotten/forgiven

(yOUR elected) president al gore (deciding not to wait for the much anticipated 'lonesome al answers yOUR questions' interview here on /.) continues to attempt to shed some light on yOUR foibles. talk about reverse polarity; []

When will people learn? (5, Funny)

Kuukai (865890) | more than 6 years ago | (#21985782)

Wireless power was simply never meant to be. Nikola Tesla tried it, and look what happened to him. He's DEAD!
I wouldn't touch wireless power with a ten foot, umm... wire.

Re:When will people learn? (0)

cpaalman (696554) | more than 6 years ago | (#21987518)

So you are saying that if wireless power WAS meant to be... then Nikola Tesla would still be alive? Because he lived to a ripe old age of 86 []

Gyroscope (1)

COMON$ (806135) | more than 6 years ago | (#21985802)

Can someone explain if this is a matter of transferring electrons between two devices, eg the source and recipient of the energy? Wouldn't we be better off either A: improving batteries, or B playing with an source that creates an event that would cause a pendulum of sorts to charge a device?

Re:Gyroscope (1)

zehaeva (1136559) | more than 6 years ago | (#21986138)

using magnetic induction(my preferred method) is a matter of passing some wires through a moving magnetic field, which then inducts a current in the wires. any beginning physics course can explain this phenomena. its the same way we get power from waterfalls and dams and its how electric cars work and how induction (theres that word again) stove tops heat your metal pans. its really nifty.

i am too lazy to post a wiki link.

Re:Gyroscope (1)

COMON$ (806135) | more than 6 years ago | (#21986820)

Yes I am aware of that phenomena, it powers my flashlight :) What I am asking though is if there could be an event in a location such as a magnetic field that pulsed or something that could be used to control the rhythm of the wires so that when you were in a location where this event occurred the device's "Charger" would be able to use it to create a current without actually passing anything harmful through the air.

Tough...No Easy Answer (2, Insightful)

BoRegardless (721219) | more than 6 years ago | (#21985850)

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".

Wireless power? (3, Insightful)

Gavin Rogers (301715) | more than 6 years ago | (#21985854)

Already invented. Next! []

Re:Wireless power? (3, Insightful)

thatskinnyguy (1129515) | more than 6 years ago | (#21985996)

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:Wireless power? (2, Informative)

Anonymous Coward | more than 6 years ago | (#21986776)

Telsa was an absolute prodigy. It's a damn shame he is not more often mentioned in the history and school books!

Don't know who he is? Take 10 mins. and see that he is an equal to names like Einstein and Newton: []

Really, just do this, open your eyes!

He had wireless power working with his 'radiant energy' approach... almost with zero loss.

There is not a single student being taught the complete thing when it comes to EE. Maxwell's original theories have been simplified by Heaviside; this is why so many interesting behaviour of electrical systems is lost. As a result, this missing part of EE is not researched anymore.. at least not in public projects..

(Public) EE is still in it's infancy and free electricity is possible, 'from the very wheelworks of nature'.

Re:Wireless power? (2, Insightful)

aix tom (902140) | more than 6 years ago | (#21986990)

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.

omni directional power transmission? (2, Interesting)

Original Replica (908688) | more than 6 years ago | (#21985964)

So where does the power go, that doesn't make it into the device? In this day and age of energy efficiency and conservation, this seems a step backwards. Maybe that energy is slowly heating the room or maybe it's slowly increasing my risk for cancer, but either way if the vast majority of the power isn't going into the device it's being wasted. Tis tech might have some specific applications where the wirelessness is of true overall benefit, but everyday hand held devices aren't it. As global energy demands continue to grow using something like this to charge your cellphone will become a hallmark of bourgeois ass-hattery.

Re:omni directional power transmission? (1)

EW87 (951411) | more than 6 years ago | (#21986092)

Charging cable have a median efficiency rate of 57% as stated above. The magnetic solution has already been known to reach 98.5 efficiency. I would trust the RF power more than the magnetic solution, simply because magnet + credit card = 0.

I like wires! (2, Insightful)

jabjoe (1042100) | more than 6 years ago | (#21985998)

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.

Re:I like wires! (0, Flamebait)

JCSoRocks (1142053) | more than 6 years ago | (#21986206)

Yeah, cell phones are the work of the devil! I'll take a soup can and a string over that any day. That way I know for sure who I'm talking to!

will destroys (2, Funny)

Thuktun (221615) | more than 6 years ago | (#21986018)

will magnetic coupling destroys your HDD
Oh, noes! They be destroying my disks!

It will be the one.... (1)

asaivan (1025940) | more than 6 years ago | (#21986076)

...which is probably the most harmful to human health, and which allows corporations the most ability to cut corners, maximize profits, and make off like bandits while people quietly contract leukemia.

Question (1)

kellyb9 (954229) | more than 6 years ago | (#21986162)

With all the cancerous death rays bouncing around now, I have to ask - is there a possibility of major health concerns, and have they been fully examined? I just have some reservations about shooting electricity around my house.

Re:Question (1)

mfbatzap (1216220) | more than 6 years ago | (#21986770)

but unlike electromagnetic waves, magnetic waves does not affect humans because they don't easily interact with the environment. furthermore, they actually demonstrated the technology with a lappy.. i guess the magnetic field ain't strong enough to affect HDD. I mean, your laptop itself has a magnetic source (i.e your speakers). Thus, if that ain't bothering the HDD and the product is tested and does not show any signs of HDD issues, I guess it should be ok? Not too sure abt credit card though. Anyone wanna try? CES 2008 is still on!! LOL!!

omnidirectional wireless power (5, Informative)

sluke (26350) | more than 6 years ago | (#21986166)

I'm relatively pessimistic about both of the technologies mentioned due to the inherent limitations that they pose (large leakage of radiated power or short range). I'm looking forward to seeing products based on the wireless power idea that came out of the Joannopoulos group at MIT in 2006.
The idea was that you can setup an RF wireless power transmitter in such a way that it does not actually transmit any power unless it resonantly couples to a precisely shaped receiver. This way there is little to no leakage and they claimed that the power transfer was quite efficient. I'm sure this was posted to slashdot, but I can't seem to find it. Here's a link to the paper if you are somewhere with access to Science: Science 6 July 2007: Vol. 317. no. 5834, pp. 83 - 86 [] and here's [] a link to the press release by the MIT news office (no subscriptions required).

Re:omnidirectional wireless power (1)

12357bd (686909) | more than 6 years ago | (#21986670)

Tesla was the master of Magnetics and Resonance. That paper states just a 60W 40%efficient 2mts power transmission setup, sorry but for now MIT guys just look like amateurs.

Re:omnidirectional wireless power (1)

mfbatzap (1216220) | more than 6 years ago | (#21986846)

I read that paper before. And in countries where AC supply oscillates at 50Hz, how are you gonna get 1Mhz for resonance to work? You'll lose lotsa power generating the high frequency magnetic field (if i'm not wrong).

Re:omnidirectional wireless power (3, Informative)

Big_Breaker (190457) | more than 6 years ago | (#21987652)

Sorry but you have this one wrong - converting mains AC to 1mhz is very easy. A common switch mode power supply chops the 50/60hz AC from the wall into a 100khz to 1Mhz waveform with a common (but fast) MOSFET. The chopped signal is then run through a stepdown transformer. The transformer and ripple filtering capacitors in the second stage can be MUCH smaller and more efficient due to the higher input frequency. In this way the high frequency generation is effectively free for a wireless power system, since most DC converter will have a high frequency first stage anyway.

The resonant coupling is the hard part. Switch mode frequency chopping is bog standard.

It's called "WiTricity" (2, Informative)

replicant108 (690832) | more than 6 years ago | (#21986752)

As I mentioned elsewhere, the BBC named it as one of the 'technologies of the year' - The technology with impact 2007 []

Re:It's called "WiTricity" (1)

sluke (26350) | more than 6 years ago | (#21987066)

Thanks for the info, I did a quick search to see if it was being commercialized and found nothing. That link showed something that makes me pause though, the receiving coil looks HUGE! I am assuming that to get to a smaller coil they would have to use a higher frequency field which I'm assuming will decrease range. Hmmm. I guess I should just do the math myself and see....


thoolie (442789) | more than 6 years ago | (#21987418)

Yea, this group is doing what tesla did a hundred years ago, but it's still neat. They currently are on what would be considered "the cutting edge" of this field, no pun intended. The thing that's been a killer in the past has been the power generation and conversion efficiency (30%). The trick is getting power electronics to switch at ~10MHz without losing 60% of your total power input. The thing that makes all of this so interesting, is that advances in SiC (silicon carbide) technology are just opening up the high frequency, high power, high efficiency box. Thus, making wireless resonant inductively coupled power transfer viable (at least for distances of less than 3m).

Re:omnidirectional wireless power (1)

xannik (534808) | more than 6 years ago | (#21987832)

I agree completely. If these MIT guys don't start a company based on this technology somebody else better, because it seems obvious to me that this is the best wireless power solution to date and it seems like it would be easy to standardize the industry on it. Is there any news on what these guys are currently doing with the technology?

It is simply a bad idea (1, Informative)

damburger (981828) | more than 6 years ago | (#21986174)

There is one of two ways you can get power wireless with RF radiation:

1. Send it out in all directions. Incredibly wasteful and, because of the inverse square law, has to be so powerful it will interfere with other stuff.

2. Send it out in a narrow beam. I really wouldn't want to be standing in between a laptop and an outlet if this were the method...

Either way, I prefer living in a home that isn't a microwave oven.

This sounds familiar... (2, Funny)

arotenbe (1203922) | more than 6 years ago | (#21986268)

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?

The future? (1)

nurb432 (527695) | more than 6 years ago | (#21986330)

I bet Tesla does not get any credit for doing it decades ago.

Is Plugging in Really that Bad? (1)

Roman Geyzer (1215500) | more than 6 years ago | (#21986380)

After all, it does work! I mean, I can't wait to have to set the WEP Key on my wireless power router! "Honey, why did the power go out?" "Wait, I'm going to reset the router!"

Misleading thoughts... (2, Insightful)

Velorium (1068080) | more than 6 years ago | (#21986384)

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.

Pacemakers (2, Interesting)

Stooshie (993666) | more than 6 years ago | (#21986400)

One thing not mentioned (particuarly with the magnetic induction system) is how pacemakers are affected.

At least with MRI scanners there are notices everywhere about people with pacemakers. If these things become widespread people with pacemakers are going to have to avoid a lot of places.

Re:Pacemakers (0)

Anonymous Coward | more than 6 years ago | (#21987868)

Here's a link to IEEE: []

There have been methods to charge pacemakers through inductive coupling.

Fields are pesky, they never stay put. Solution... (1)

goodmanj (234846) | more than 6 years ago | (#21986534)

The problem with wireless power transmission is that it's hard to control where your electromagnetic fields go. They tend diverge as an inverse square law, scatter and bounce all over and be absorbed by things that are not your antenna. This is wasteful, because your wireless power ends up heating up trees, grass, and rivers rather than powering your city, and dangerous, because if a human absorbs even a tiny fraction of a gigawatt power transmission from a generation plant, he'll be cooked.

In recent years, engineers have come up with several schemes to prevent the scattering and leakage of electromagnetic energy. The most clever involves the use of a long strand of copper, which acts as a "guide" to shape and direct the EM fields and keep the power tightly focused and moving in the right direction.

Re:Fields are pesky, they never stay put. Solution (0)

Anonymous Coward | more than 6 years ago | (#21987120)

The reactive field stays put quite nicely. If one could set it up without generating that pesky wandering radiating field...then we'd be all set. Who cares if it's a cube law device, if your not losing anything to radiation you can make the field as strong as you like. Sure, your uncle with the CABG might not like having the tie wires ripped out of his sternum but what do you care, you're in the will.

None of the Above.. (1)

Talkischeap (306364) | more than 6 years ago | (#21986730)

Power over Glass/Plastic Fiber.

Thats the Future of Power Transmission.

All the rest are Losers Games.

Nikola Tesla (1)

traveller604 (961720) | more than 6 years ago | (#21986750)

Did it like what, 70-80 years ago? These guys are a little late..

Wasteful (1)

fozzmeister (160968) | more than 6 years ago | (#21986872)

Isn't this technology very wasteful, a huge proportion of the power must just escape into the air. I would not be too surprised if it ends up getting banned.

Mister Ignorant Here .. (1)

kthejoker (931838) | more than 6 years ago | (#21986930)

What's wrong with wired power, exactly?

Way better ideas (2, Informative)

Casandro (751346) | more than 6 years ago | (#21986964)

Well first of all, the biggest untapped energy source on the planet still is an increase in efficiency. Why does my laptop need take 60 Watts of power in order to heat up my lap?
Why do we have displays in mobile devices that waste 5/6 of the light they generate?
Why do we still have processors that take _Watts_ of power althought alternatives with milliwatts are available?

I believe that a 1 Watt laptop-like device is definitely possible. It won't have a colour screen nor Windows Vista, but it would do everything you want it to do. Just look at old Psions which ran for months.

Great, if standardized (1)

Animats (122034) | more than 6 years ago | (#21987000)

As I pointed out previously [] , there were at least three companies demonstrating wireless charging systems. This new article lists two more, Powercast and Fulton Innovation.

Short-range systems using long-wave near-field RF are probably the way to go. Power ratings can be quite high. The GM EV-1 charger used an inductive paddle operating at 400KHz, and could transfer kilowatts across about half an inch at 90%+ efficiency. The MIT system [] operates in the 4-10 MHz band.

Great, more incompatible standards (1)

vanyel (28049) | more than 6 years ago | (#21987108)

One of the big advantages to this idea is not having to have a bazillian different wall warts for every separate device. Usually unlabeled so that 6 months later, you have no idea what goes with what if you haven't rigorously kept things together and/or labeled them yourself, not to mention having to lug around a few kilos of the things when you travel.

Except now they're going to beta/vhs us so some things need this charger and some need the other charger. If you get it wrong 6 months later, you've got a device you absolutely needed charged and you put it on the wrong pad, leaving you stranded high and dry.

Re:Great, more incompatible standards (1)

OutOfMyTree (810249) | more than 6 years ago | (#21987394)

So we could use magnetic coupling, wireless power, or just standardize our wired power connectors? Which method seems likely to win out in our current world?

Wireless Power (0)

Anonymous Coward | more than 6 years ago | (#21987332)

1. Spotlight
2. Photovoltaic Panel Wired to Laptop Battery
3. ????
4. Profit!

What is the Future of Wireless Power? (1, Funny)

Cctoide (923843) | more than 6 years ago | (#21987554)

Hmm. Good question.

Someone will hire a company to implement this. This company will have a very stubborn, self-righteous president, but it will manage to get a working solar satellite into space, along with a terrestrial reception station. However, efficiency will not be as high as expected. Eventually a decision will be made to cut public spending on this technology, and the president will say, I quote:

A few days later, everyone will be weeping over the catastrophe caused by a mysteriously misaligned microwave beam. The president of the company will be nowhere to be seen, but his name will start appearing unusually frequently in pump-and-dump stock scams.
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