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Wireless Power Demonstrated

kdawson posted about 5 years ago | from the spooky-action-at-a-distance dept.

Power 124

Necroloth and other readers sent in the story of Witricity's latest demo at the TED Global conference in Oxford, UK. The company is developing a system that can deliver power to devices without the need for wires. The idea is not new — electrical pioneers Thomas Edison and Nicola Tesla assumed that power would be delivered wirelessly. The BBC quotes the inventor behind Witricity's tech as saying that Tesla and Edison "...couldn't imagine dragging this vast infrastructure of metallic wires across every continent." eWeek Europe notes some hurdles the technology must overcome: "The 2007 experiment it is based on had an efficiency of only around 45 percent, but [Witricity's CEO] promised power delivered wirelessly would start out 15 percent more expensive than wires, and improve on that." Intel has also demonstrated wireless charging.

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prist puck off (-1, Flamebait)

Anonymous Coward | about 5 years ago | (#28812931)

just fuck off already, tesla was a cunt

Re:prist puck off (0)

Anonymous Coward | about 5 years ago | (#28813701)

Something is deeply wrong with the bbc; You can witness it yourself in their radio broadcasts and tv shows. They make a great show of having some leading expert explain something to their listeners then rudely cut the expert of mid-sentence with some half-assed 'thank you for explaiiiiiiiiiinning all of that' just so that they are able to maintain their fucking pre-determined schedule. What the fuck? Maybe if they could pretend more effectively that they gave a shit what some guy had taken time out of his day to explain, the general public would feel that the taxation imposed by the bbc, almost as an arm of the fucking government, would be worth it, rather than just a sink-hole for middle-class arts graduates who feel it is beneath them to try to understand HOW THE WORLD WORKS ?

<rant>

So what are the chances of... (1)

Drakin020 (980931) | about 5 years ago | (#28812953)

A wireless Taser?

Re:So what are the chances of... (1)

EdZ (755139) | about 5 years ago | (#28813455)

Only if the person you're aiming at happens to have hooked the correct resonant antenna into their muscles.

Re:So what are the chances of... (0)

Anonymous Coward | about 5 years ago | (#28813859)

If I were a conspiracy theorist, I'd say the government would start feeding our babies pills to subtly alter their bone structure or do unnecessary surgery to add in antenna to resonate with secret government wireless tasers.

But that's just wonky because of the logistics of the plan.

Re:So what are the chances of... (1)

bertoelcon (1557907) | about 5 years ago | (#28814473)

If I were a conspiracy theorist, I'd say the government would start feeding our babies pills to subtly alter their bone structure or do unnecessary surgery to add in antenna to resonate with secret government wireless tasers.

But that's just wonky because of the logistics of the plan.

Call it a immunization shot and require it for doing pretty much anything, and none the wiser.

Re:So what are the chances of... (2, Interesting)

powerlord (28156) | about 5 years ago | (#28814399)

Okay ... so what about a taser that works by firing the "head" of the taser but without the trailing wires.

Heck, if that sort of approach worked (a huge "if" personally), the next obvious steps would be to miniaturize the "heads", perhaps make them burn out after a single use (cheap materials, built in resistor that burns out as the current crosses it) ... ... then pack a few of them into a magazine and we've created a rather nice "Assault Weapon" when you're trying to keep casualties to a minimum and are only dealing with "soft" targets (Law Enforcement/Security/Hostage applications sound the most likely).

I predict these are "five to ten years away". ;)

YMMV but I still think it sounds like a neat concept, even if the technology can't/won't support the idea. The single biggest hurdle to the idea is the current need for a stun gun to have those wireless leads leading back to the "body" of the gun. If you can find a away to remove those (even if it means you are now firing a small projectile that isn't expected to penetrate much if anything), it can open the advancement up quite a bit.

Re:So what are the chances of... (1, Interesting)

Anonymous Coward | about 5 years ago | (#28815139)

Okay ... so what about a taser that works by firing the "head" of the taser but without the trailing wires.

check out the Tetanizing Beam Weapon [archive.org]

Re:So what are the chances of... (1)

EdZ (755139) | about 5 years ago | (#28815207)

So, essentially the piezoelectric shotgun rounds that are already in development then.

Re:So what are the chances of... (1)

Quothz (683368) | about 5 years ago | (#28815777)

Okay ... so what about a taser that works by firing the "head" of the taser but without the trailing wires.

Not what you meant, but you can fire the whole thing [wired.com] . From a shotgun.

Re:So what are the chances of... (1)

Jamie Lokier (104820) | about 5 years ago | (#28815163)

Try UV lasers to ionise a path through the air and send your taser pulse down that.

Standard interface? (3, Insightful)

elwinc (663074) | about 5 years ago | (#28812961)

Resonant transfer is great stuff, but what we need even more is a standard interface so that all our rechargable devices can recharge at the same source.

Re:Standard interface? (1)

BCSWowbagger (1230826) | about 5 years ago | (#28813259)

My understanding of the tech was that any device using a charger with the same resonance as the base station would be able to suck down power, dividing the base station's emitted power evenly between all "connected" devices. Of course, I only read the BBC article, so I might well be wrong.

FRAUD ALERT -- Slashdot sucked in again! (0)

Anonymous Coward | about 5 years ago | (#28814727)

Disgusting.

This is old stuff (2, Funny)

hannson (1369413) | about 5 years ago | (#28813443)

Thinkgeek has sold wireless extension cords for a long time [thinkgeek.com] . I wonder if Witricity has solved the issue about domestic cats getting in between the source and destination...

Re:This is old stuff (0)

Anonymous Coward | about 5 years ago | (#28813819)

That's an April Fool's Joke.

Re:Standard interface? (1)

jeffliott (1558799) | about 5 years ago | (#28813475)

This is only a good idea if the standard included a communication bus and spec for voltage, polarity, and amperage negotiation. Without these things, we would have a lot of burnt out equipment. Unfortunately, this would also increase the complexity and cost of the small devices and chargers, but hopefully the volume of the components used would lessen the expense.

Re:Standard interface? (3, Insightful)

dgatwood (11270) | about 5 years ago | (#28813995)

I think that's massive overkill. Just provide a 12V rail, a 5V rail, and a ground using a polarized plug. Heck, you can probably dispense with the 12V rail. A 5V rail by itself should cover the vast majority of portable electronics these days. Amperage negotiation? Build the supply so that if it is under too much load, it sheds power connections, then periodically switches which jacks are shed. That's much cheaper to design, and it doesn't unnecessarily add to the complexity of the devices that use it.

Re:Standard interface? (1)

jeffliott (1558799) | about 5 years ago | (#28814199)

That would be great, if 1.5v-3v devices could automagically operate safely with 5v. Essentially, your concept requires the device to convert DC voltage, which isn't cheap, and generally very wasteful. However, on the charger end, they could have an switchable transformer and produce the desired voltage.

Re:Standard interface? (2, Insightful)

vivian (156520) | about 5 years ago | (#28815417)

DC to DC regulators are very cheap, for low power needs - which is what you are talking about for most small devices that use wall warts.

Here's a bunch of devices, with datasheets & prices.
ahref=http://www.semiconductorstore.com/pages/asp/category.asp?id=56rel=url2html-27418 [slashdot.org] http://www.semiconductorstore.com/pages/asp/category.asp?id=56>
They start at about $1 and go all the way up to 3.86 for a device that can do dual power rails of exactly that spec - 5v to 3.3v.

Of course, if you don't care quite as much about efficiency, or you are only stepping down your voltage a little, you can always use an LM78xx (where xx is the output voltage needed) they cost a buck or two also, and with very few additional components needed.

Re:Standard interface? (1)

node 3 (115640) | about 5 years ago | (#28814073)

This is only a good idea if the standard included a communication bus and spec for voltage, polarity, and amperage negotiation.

That's electricity. All that matters here is frequency and amplitude. It'll be up to the receiving device itself to manage voltage and polarity. Amperage is a matter of the transmitter having a sufficient amplitude at its particular frequency, nothing more (power = amps x volts).

USB (1)

HalAtWork (926717) | about 5 years ago | (#28814683)

But then, many devices also want their own USB cable interface...

Thomas Edison ??? (3, Insightful)

nurb432 (527695) | about 5 years ago | (#28812967)

Electrical pioneer my ass, he just got lucky once and was able to afford to hire good talent ( like Nikola ). But i totally agree that Tesla proved it was possible ( and WAS a pioneer ). But he also proved that it takes more then tech to make such a project work, it also needs funding. As brilliant as he was, a businessman he wasn't, and we were set decades behind on projects such as this.

Re:Thomas Edison ??? (0)

Anonymous Coward | about 5 years ago | (#28813019)

I concur Tesla was responsible for the TESLA COIL. Edison was a thief and an idiot who caused a large number of house fires insisting DC was safer than A/C he had no clue.

Tesla invented 90% of the components required to build a radio, edison did not. Bose put together the first functional radio, yet edison got the patent.... Also Edison worked at the patent office. Tesla is the most underrated inventor of all time and he deserves better.

Re:Thomas Edison ??? (1)

MightyMartian (840721) | about 5 years ago | (#28813035)

Edison was very much a crook. How it is exactly that Tesla ended up being labeled some sort of lunatic while Edison is considered some sort of modern Renaissance Man is quite beyond me.

Re:Thomas Edison ??? (1)

peragrin (659227) | about 5 years ago | (#28813351)

It's called politics. Edison new how to work the crowd, Tesla was a lunatic mad scientist. Edison new how to play the game of marketing, tesla annoyed his own followers. Edison was the Bill Gates of his day. an acceptable scientist, but a really good marketer. Tesla is like RMS. a mad scientist.

Re:Thomas Edison ??? (0)

Anonymous Coward | about 5 years ago | (#28813773)

Don't ever compare Tesla to RMS. N. Tesla was a genius, Stallman is a fucking idiot.

Re:Thomas Edison ??? (2, Insightful)

Corporate Troll (537873) | about 5 years ago | (#28813977)

Except perhaps that Stallman was pretty much always right in predicting abuses of software licenses..... The man may be difficult to cope with, but he most certainly is a visionary. That's where the analogy with Tesla is quite fitting.

Re:Thomas Edison ??? (1)

PinkyGigglebrain (730753) | about 5 years ago | (#28815297)

You say "Mad Scientist"
I say "Grumpy Visionary"
cool site [printfection.com]

IMO, Edison was a Business genius like Gates but Tesla was a true Creative Genius, not just an inventor.

Re:Thomas Edison ??? (1)

sjames (1099) | about 5 years ago | (#28813379)

The same way psychopaths on the dole get named "captains of industry" while people who actually work their asses off every day barely make enough to live on.

Re:Thomas Edison ??? (1)

kheldan (1460303) | about 5 years ago | (#28813389)

How? More or less the same way that VHS became the standard for consumer video recording over Beta: Marketing.

Re:Thomas Edison ??? (0)

Anonymous Coward | about 5 years ago | (#28813489)

History is written by the victors.

Re:Thomas Edison ??? (1)

pitu (983343) | about 5 years ago | (#28813953)

exactly, edison was the one that burned cats with the "evil" alternative tesla current on public places... and is the one that "invented" electrocution... so i do find it revolting that his name ends up next to tesla's with the adjective pioneer...pffff on the other hand, though tesla experimented on wireless power transfer I have not seen any proof that he actually did it... there is much speculation about his work...does anyone have references that he actually proved it was possible? ...and also, tesla was seeking for a wireless power transfer, not because he was unable to imagine the "modern" ultra costly and barbaric infrastructure but because he believed that wireless transfer was the only way to provide electricity [and progress] to any how ever distant point of the world... he also talked about some kind of a resonator in frequency with the earths own oscilations that "could" make possible the transfer of power to any point of the planet...one would just need to plug to the ground....

Re:Thomas Edison ??? (1)

anotherzeb (837807) | about 5 years ago | (#28815253)

Tesla wanted an all wireless electricity transfer system from generator to device, but couldn't get the transfer to go more than about a couple of metres, so the idea got dropped, even after the idea of having a generator every couple of blocks was suggested.

The resonator you mentioned was far too effective - it ended up destroying his building - so maybe resonating wasn't the way to go either.

I don't remember the original sources for these, but here [blogspot.com] is a film about him and his work - sounds like parts of his life were pretty good.

Re:Thomas Edison ??? (1)

davcorp (465418) | about 5 years ago | (#28815785)

I'm pretty sure he fried elephants also.... just my 2cents....

Re:Thomas Edison ??? (0)

Anonymous Coward | about 5 years ago | (#28813037)

-1 Troll

Re:Thomas Edison ??? (1)

slimak (593319) | about 5 years ago | (#28813287)

Edison has gotten far more coverage in the history books (at least US ones), He was probably best at business, although he is known as an inventor. On the other hand, Tesla was, without a doubt, the greatest engineer that has ever lived. He is proof that a formal advanced education is not necessary for scientific greatness. It is too bad that most people don't realize the impact he truly had.

Re:Thomas Edison ??? (1)

nurb432 (527695) | about 5 years ago | (#28813511)

ya, i should give Edison credit for his business savvy.

Just was irritated to see his name in the same sentence as Tesla in this context and went off on a mini-rant.

Re:Thomas Edison ??? (3, Interesting)

lawnboy5-O (772026) | about 5 years ago | (#28813363)

My grandmother worked for Thomas Edison - so I the FUD on Edison I can speak to directly as she was my intellectual mentor growing up - and yes we spent hours and hours talking about that crazy Edison.

Some points you should know:
Most of the consumer devices you use today are direct descendants of Edison's inventions.
Edison was no Crook either - even if only paying my sweet grandmother ~17 cents a day around the 1920's.
He was indeed eccentric toward the later years of his life however, and experienced what many would consider a form dementia today.

His list of inventions towers over just about all other modern inventors - I suggest all of you look them up - there are many, many stories to tell. From movies to music, refrigeration to your TV, he's been involved in some way.
...and by the way - it was Marconi that invented most of what was later attributed to Tesla... and returned to Marconi only recently by world courts.

Re:Thomas Edison ??? (1)

nurb432 (527695) | about 5 years ago | (#28813757)

Most of the consumer devices you use today are direct descendants of Edison's inventions.

They were 'his inventions' only because his employees created them. So i guess technically you are correct, but that is stretching intellectual honesty. Sort of like saying Bell Labs invented the silicon transistor, when it was actually employees of the labs that did..

. ...and by the way - it was Marconi that invented most of what was later attributed to Tesla... and returned to Marconi only recently by world courts.

I call BS. And even if its true they gave them back, Marconi used Telsa's work to achieve it, AFTER Tesla did, so Tesla earned the credit and should retain it.

Re:Thomas Edison ??? (1)

lawnboy5-O (772026) | about 5 years ago | (#28815291)

Your admiration/enthusiasm for Tesla is not unwarranted - his genius was original, but you need to loosen up on the others.... Marconi did it before Tesla but both indpendently, actually. And as far as Edison goes, he was indeed hard to work for, but to claim he raped his employees for everythng is far too fetched, and outright false. He did indeed depend on his employees more in his later years, but his genius was legit, and his Inventions genuinly his own.

Re:Thomas Edison ??? (2, Insightful)

kliklik (322798) | about 5 years ago | (#28813771)

...and by the way - it was Marconi that invented most of what was later attributed to Tesla... and returned to Marconi only recently by world courts.

Actually, it's the other way around. Check [wikipedia.org] your [tfcbooks.com] facts [wikipedia.org] .

Re:Thomas Edison ??? (1)

lawnboy5-O (772026) | about 5 years ago | (#28815339)

This is interesting - but wiki is wrong here IMHO. The credit in question on many of the conflicts between Marconi and tesla have been on going for decades... Discovery and History both in recent docmentations claim the opposite... And give Marconi the credit... As do some governing bodies and courts. But i guess we will have to wait for more compeling evidence for the truth to be known ( if wiki is correct).

Re:Thomas Edison ??? (1)

The_mad_linguist (1019680) | about 5 years ago | (#28815645)

Edison invented one major thing:

The mass production of inventions.

Everything else was either stolen or subcontracted.

Did you know Edison didn't believe in Ohm's law?

Re:Thomas Edison ??? (4, Funny)

Heed00 (1473203) | about 5 years ago | (#28813923)

Bah. He came up with that cool electric hammer that was recently discovered as well as the extra hinged legs on chairs to stop you falling over if you lean back too far.

Re:Thomas Edison ??? (2, Informative)

westlake (615356) | about 5 years ago | (#28814673)

Electrical pioneer my ass, he just got lucky once and was able to afford to hire good talent

Luck favors the prepared.

1869 Stock ticker

1874 Quadruplex telegraph [wikipedia.org] [Polar modulation]
Rights sold to Western Union for $10,000. [about $170,000 in 2005 dollars Historical Value of U.S. Dollar [mykindred.com] ]

Menlo Park was in the business of invention. That in itself was a new idea.

1877 Phonograph

The most interesting thing about the phonograph is that no one saw it coming.

1880 Incandescent lamp.

Edison needed a lamp which could be wired in parallel. His team had to design every component - down to the wiring, fixtures, fuses and switches that would be safe for use in the home.

Tesla and Edison predicted it... (2, Interesting)

roc97007 (608802) | about 5 years ago | (#28812987)

...but as geeks we should remember that Heinlein cautioned against it.

Re:Tesla and Edison predicted it... (1)

Nethead (1563) | about 5 years ago | (#28813655)

Are you talking about "Blowups Happen" or "Magic Inc."?

Re:Tesla and Edison predicted it... (1)

roc97007 (608802) | about 5 years ago | (#28813785)

No, Waldo. "Blowups Happen" was a (premature, somewhat unwarranted) cautionary tale about nuclear power. Magic Inc could be a cautionary tale about... lessee... nationalized health care. Yeah, that works for me. But Waldo (usually bundled with Magic Inc) was (at it's core) about human physical deterioration brought on by widespread broadcast power.

Re:Tesla and Edison predicted it... (1)

WinterSolstice (223271) | about 5 years ago | (#28814071)

Well, we haven't listened to Gibson about the "black shakes" caused by too much RF - heck we put RF gear near our heads daily.
Why would we stop now when we can charge it while wearing it? (cancer? naaaaaaah)

Re:Tesla and Edison predicted it... (1)

Nethead (1563) | about 5 years ago | (#28814391)

That's right, it's been decades since I've read them. Time to dig in the book pile again.

Thanks.

Re:Tesla and Edison predicted it... (1)

Chyeld (713439) | about 5 years ago | (#28814039)

Heinlein also wrote about a character that was effectively immortal. Banged his daughters, his sisters, his clones, went back in time and banged his mom and his dad, gave his best friend a sex change so he could bang it, got the AI running a planet and the AI running his ship bodies cloned from him (so he could bang them) and really pretty much humped everything that moved, while being a bigger bad ass than the illicit love child of Dirty Harry, Chuck Norris, and Vin Disel.

A good wordsmith, but not exactly Cassandra.

Re:Tesla and Edison predicted it... (1)

nine-times (778537) | about 5 years ago | (#28814819)

Maybe it just hasn't happened yet?

Re:Tesla and Edison predicted it... (0)

Anonymous Coward | about 5 years ago | (#28815079)

Lazarus Long? It's been a while...

Re:Tesla and Edison predicted it... (0)

Anonymous Coward | about 5 years ago | (#28814395)

Actually Tesla did it to some extent...

Efficiency? (1)

jdgeorge (18767) | about 5 years ago | (#28813001)

Mmmm; I'm under the impression that the problem with contact-free power is a significant loss in efficiency. So, if I have to use 25% more power (for example) to charge all my devices just so I don't need to connect a wire, that sounds like a great way to make stuff cost more due to increased electricity demand.

If I were building power plants, of course, this would sound like fantastic news.

the problem with contact-free power (1)

wonkavader (605434) | about 5 years ago | (#28813113)

Mmmm; I'm under the impression that the problem with contact-free power is a significant loss in efficiency.

I, on the other hand, always thought the problem with contact-free power was cancer.

Re:the problem with contact-free power (1)

jeffliott (1558799) | about 5 years ago | (#28813561)

Mmmm; I'm under the impression that the problem with contact-free power is a significant loss in efficiency.

I, on the other hand, always thought the problem with contact-free power was cancer.

Considering the large amount of EMI emitting transformers and oscillating devices found in the common nerd's dwellings, I doubt adding a little more would hurt all that much, relatively speaking that is.

Edison? (2)

Corson (746347) | about 5 years ago | (#28813021)

I don't know about Edison but Tesla certainly carried out experiments proving that wireless energy transfer is possible.

Re:Edison? (3, Informative)

n3umh (876572) | about 5 years ago | (#28813401)

It's not only possible, but really damn easy to do.

You can build a reasonably efficient resonant power transfer doohickey in your backyard out of some copper tubing, some low loss tuning capacitors, a RF power generator, and some diodes and filter caps on the far end to turn the received RF into DC.

I've built one to couple 4MHz pulses across to a rotating experiment for ultrasound measurement: http://n3ox.net/files/us_ring.jpg [n3ox.net]

You couple 'em that tightly, and they're like 99% efficient at transferring power.

But even with Tesla aside, this isn't new... it's just not as vastly useful as people re-discovering it seem to think it is. It doesn't work over gigantic distances, only moderate ones, and there's no engineering you can do to get around that. It's near-field coupling between resonant circuits. That said, I think it might end up pretty useful for non-contact charging of your electric car like TFA suggests. That's a *good* application for it, and it has more efficiency than "ordinary" inductive coupling.

Re:Edison? (1, Interesting)

Ryvar (122400) | about 5 years ago | (#28814487)

But even with Tesla aside, this isn't new... it's just not as vastly useful as people re-discovering it seem to think it is. It doesn't work over gigantic distances, only moderate ones, and there's no engineering you can do to get around that.

The misunderstanding a lot of people have is that they think Tesla was chasing *truly* wireless power - when in fact this was probably never his goal. Tesla was always chasing after something he called "longitudinal waves" in an attempt to perform worldwide "wireless" power transmission - he even called one of his companies World Wireless [pbs.org] .

Tesla certainly wasn't foolish enough to believe this distance was possible with purely wireless transmission, but instead investigated single-wire transmission systems using the ground as the single wire. His initial success at single-wire transmission was at Colorado Springs in 1900 with three lightbulbs in a closed circuit loop with no power source and a transmission source a hundred feet away. In this experiment, as in his later vacuum tube powering experiment performed at considerably greater distances (eventually miles away), the objects in question were always had a metallic contact with the ground.

Take a look at figures 3, 6, and 7 on this page: http://amasci.com/tesla/tmistk.html [amasci.com] . This seems the most likely explanation for the experiments at Colorado Springs and Wardenclyffe. Wardenclyffe in particular is where we find Tesla sinking iron rods 300 feet into the ground, burning out local power station dynamos with his energy demands, and constructing a massive omnidirectional transmission tower.

The reasonable conclusion from all this is that Tesla was always pursuing single-wire transmission schemes in which literally the entire Earth itself was the single wire, and the transmission medium for the wireless component was the entire ionosphere. "World Wireless" seems to have been meant quite literally, which was in keeping with all we know about Tesla's personality. Unfortunately, as we all know, Tesla needed something like an order of magnitude more funding than JP Morgan was willing to provide - particularly after Marconi.

Beyond that, though, Morgan would have probably pulled the project even if Tesla had gotten it working: if single-wire worldwide transmission was in fact his intention, it would've been impossible to meter consumption on a per-user basis.

Fortunate side effect (1)

drukawski (1083675) | about 5 years ago | (#28813079)

Turns out the strong EMF fields created by the technology also have the bonus side effect of microwaving tinfoil hat conspiracy theorists skulls.

Retarded. (4, Insightful)

girlintraining (1395911) | about 5 years ago | (#28813121)

Blasting large amounts of EMI solely to avoid the need to put a battery in something is stupid. Right now EM radiation is controlled to the lowest levels it can practically be in order to achieve some transfer of information between two or more points. Any power transfer system is going to muck up what's already in the air. It's called Shannon's Law -- and no matter how you sex up the technology, the fact is you're raising the noise floor doing this.

Bad engineer. No cookie for you.

Re:Retarded. (1, Insightful)

n3umh (876572) | about 5 years ago | (#28813311)

It's called Shannon's Law -- and no matter how you sex up the technology, the fact is you're raising the noise floor doing this.

Bad engineer. No cookie for you.

Except that energy transfer is not information transfer, and doesn't really require any bandwidth. Of course, every emission has *some* bandwidth due to noise, etc, but you should be able to do wireless power with very narrow band oscillators and I suspect you have confine emissions to the the ISM (industrial, scientific, and medical) bands. Maybe it needs a little bit of slow digital transmission if you need to sync devices and chargers beyond just whether or not there is another resonant device around (you don't want charging stations trying to feed power to each other).

But the fact of the matter is that resonant power transfer requires sharply resonant circuits, so you can't emit much power over a wide bandwidth even if something goes wrong.

Re:Retarded. (1)

kheldan (1460303) | about 5 years ago | (#28813427)

Hear, hear!
We'll have practical flying cars before we have practical wireless electricity. Hell, we'll probably have over-unity energy before we have practical wireless electricity!

Re:Retarded. (1)

hannson (1369413) | about 5 years ago | (#28813483)

How is that any different than Ethernet over Power?
 
(I'm not an engineer, someone please explain)

Re:Retarded. (1)

bugnuts (94678) | about 5 years ago | (#28813817)

Ethernet over powerlines noises up the powerlines, but won't add much EM interference to your wireless, e.g.. I believe the GP is saying that wireless energy transmission is going to make any wireless communication have to compete with the noise, going from a hiss to a yell, like the 2.4Ghz noise of millions of microwave ovens suddenly turning on while you're reading this on your iphone's wifi.

In practicality, that means your phone batteries will die much faster as it has to pump out 1 bar worth of power in a 5 bar zone (that is, it will have to raise the power output to be heard by the tower over the noise, even if the tower is nearby). That means your wifi will be interrupted much easier, or have much lower bandwidth, and won't be usable for long distances. And all these communication devices that have to "yell" to be heard, will be adding just that much more noise for other devices.

the energy-transfer here is non-radiative (1)

stevenj (9583) | about 5 years ago | (#28814061)

Not that you'd learn it from this non-technical news report, but the energy transfer in WiTricity is non-radiative for this and other reasons. Indiscriminately radiating power not only will interfere with other devices (and violate FCC regulations), but also wastes power by dumping it into the environment, not to mention that people tend to dislike the idea that power is being dumped into their brains. See my other post below.

Re:the energy-transfer here is non-radiative (1)

Jamie Lokier (104820) | about 5 years ago | (#28815157)

It's non-radiative only as long as there's no object in the vicinity which happens (by chance of it's structure) to resonate with it and form an antenna.

If Witricity used something like coded spread-spectrum for it's magnetic waveform, that would be very unlikely, and make stealing power more difficult too. But from the little description in the articles, it looks like it depends on a simple narrow band resonance. An unlucky mechanical structure could resonate with that and radiate.

Re:the energy-transfer here is non-radiative (1)

stevenj (9583) | about 5 years ago | (#28815365)

First of all, you don't understand the meaning of "non-radiative". Whether or not there is power transfer, it is in the near field, not the far field, and hence it is not radiative. Second, it's not sufficient to have the same resonant frequency; you also have to be impedance-matched. The combination of the two is unlikely in the extreme.

Re:the energy-transfer here is non-radiative (1)

Jamie Lokier (104820) | about 5 years ago | (#28815515)

I believe I understand the meaning of non-radiative and near-field, but I won't claim expertise.

As a simple thought experiment, a Witricity receiving coil connected by ordinary cable to a radiating antenna resonant at the same frequency, with all three components impedance matched, would clearly be a mechanical object which passively coupled with the transmitter and produced a (radiating) far field.

The transmitted field's shape is modified by antenna elements in the vicinity of the transmitter. With complex impedance, that is enough to make the whole assembly produce a far field component unless the transmitter has active compensation, i.e. it senses and adapts with a complementary field shape, which is not easy.

The question is whether the far field component so produced is so tiny as to be effectively zero, or not.

How unlikely is it?

I'm guessing it's very unlikely unless there's the equivalent of impedance matching components in just the right places in one's random household object. It's hard to judge the likelihood of that.

Perhaps "does not unintentionally couple with standardised wireless power sources" will become a design requirement for new electronic devices as they become more common :-)

Re:Retarded. (1)

grumpy_old_troll (1049646) | about 5 years ago | (#28814839)

Just because you're much closer to 102.5's radio tower doesn't mean you can't listen to 93.3.

They're not adding the Gaussian white noise that Shannon's Law refers to, they're going to pump at some specific frequency, so you presumably get to filter it out for your communication channel.

Re:Retarded. (1)

Ungrounded Lightning (62228) | about 5 years ago | (#28815063)

Just because you're much closer to 102.5's radio tower doesn't mean you can't listen to 93.3.

Get close enough to 102.5's tower and it does. And the farther it is from 93.3's, the farther you have to be from 102.5's tower to hear 93.3.

Look up "receiver quieting".

Yes they're different frequencies. But the sharp tuned circuits are AFTER the first few stages. Saturate the front end and you can forget listening to the quiet stuff.

So things like this need to be in bands far enough removed from the signals of interest that the minimal tuned circuits at the front end of the receiver can reject them adequately to keep the front end's electronics working correctly.

Re:Retarded. (1)

msheekhah (903443) | about 5 years ago | (#28815825)

This method of recharging is going to be much less harmful than the power transformers... Why? High resonance frequency EMF vs. Low resonance frequency EMF. Our entire environment is magnetic. However, it's very low resonance frequency, that we are evolved to survive in. Sure, we're going to loose efficiency with this method of charging. That's why we need to focus on research to create better power sources. Also, what if we found the magnetic resonance frequency of the earth (core/atmosphere, whatever is actually the cause) and derive power from that? Semi Free power? However, to keep from draining the planet like a battery in geological time frames, we can paint artificial structures so that the roofs are black... trapping radiant heat in the atmosphere, where it helps recharge the earth's (core/atmosphere) or something like that. Or I could just be thinking up sum guud science fiction

Re:Retarded. (1)

labnet (457441) | about 5 years ago | (#28815953)

Actually, one the main problems they will have is dealing with ETSI EN 300 330-1, which governs the field strength of inductive based transmitters.
The USA also has a similar FCC standard but in screwed up volts/m units.
We develop 134kHz RFID equipment, which pushes right on the boundary of this standard, and it aint a lot of power.
eg a 1200mm x 600mm antenna can just power a 1" RFID tag at 1.5m
Remember near field systems loose strength from the transmitter at 1/r3.

So to obey the standards and get useful power you either need to be very close, or use ferrites to help close the magnetic field.

Wireless power has been around for a few years now (2, Informative)

TheNarrator (200498) | about 5 years ago | (#28813321)

Here's a company that's had wireless power tech since 2007:
http://www.powercastco.com/ [powercastco.com]
They even won a best of CES 2007 award from CNET:
http://reviews.cnet.com/8301-12760_7-9673092-5.html [cnet.com]
They released working wirelessly powered Christmas tree lights in December 2007 as a consumer product!
http://news.cnet.com/8301-17938_105-9793204-1.html [cnet.com]
So this type of wireless power tech has been available in consumer products since 2007 and it appears that there has not been a lot of interest. I am really mystified as why nobody cares. Is it because they mistake this technology for some other kind of well known technology? I can't figure out the psychology here.

not all wireless power is the same (4, Informative)

stevenj (9583) | about 5 years ago | (#28813971)

There are several very different schemes currently being explored for wireless power transfer, with different strengths and weaknesses.
  • Radiative transfer: send a directed beam of energy from a source to a receiver. The advantage is that this can work over long distances, the disadvantage is that you need to either have fixed locations or some active tracking system to keep pointing at the receiver as it moves around, and you need some kind of automated kill switch to make sure you don't accidentally fry anything that walks between the transmitter and receiver or waste power when the receiver is not there. It looks like PowerCast [powercastco.com] and PowerBeam [powerbeaminc.com] fall into this category.
  • Traditional inductive, non-radiative power transfer. This works well, and does not transfer power when the receiver is absent, but is extremely short-range if you want any kind of efficiency; typically, the device to be charged must be sitting directly on or adjacent to the charger. The Wireless Power Consortium [wirelesspo...ortium.com] is pursuing this kind of approach.
  • Resonant, non-radiative power transfer. This relies on the source and receiver being electrical resonators at the same frequency, so that they preferentially transfer energy to one another rather than to other objects in the environment via resonant coupling. This is the approach being pursued by WiTricity [witricity.com] , where they additionally rely on resonators that couple primarily via magnetic fields (the electric-field energy is mostly in capacitors inside the devices), which have the advantage that most materials are non-magnetic at these frequencies so the power source dissipates very little energy into extraneous objects (or people). (In contrast, Tesla coils produce strong electric fields external to the device, which interact much more strongly with matter; it's no coincidence that Tesla coils are used as lightning generators.) This operates efficiently at mid-range distances although not as far as radiative transfer (meters at most), does not transfer or dissipate power when the receiver is absent, and is not directional so does not require active "pointing" of the power at the receiver. But it is more complicated than the short-range non-resonant inductive transfer, and requires careful impedance-matching of the source and receiver.

Full disclosure: I know Prof. Soljacic at MIT, who founded WiTricity, although I personally have no financial interest in the company; all of the above information is public and published, however.

Re:Wireless power has been around for a few years (1)

dissy (172727) | about 5 years ago | (#28814175)

So this type of wireless power tech has been available in consumer products since 2007 and it appears that there has not been a lot of interest. I am really mystified as why nobody cares. Is it because they mistake this technology for some other kind of well known technology? I can't figure out the psychology here.

I'm going to place a guess that it involves price, and possibly obscurity.

Admittedly, I am just going by the $400 pricetag on that tree from 2007, but most people that would be preparing and setting up a christmas tree today, have been doing so for awhile already and in most all cases don't see a drawback to the wires. They have wired things up before, so the process is pretty well understood and worked around.

Now, as a geek I would love to have these, but for me it would be specifically for the reason that they are wireless lights.
To non-geeks, the primary function of christmas lights is to pretty up the tree (well, or 'tradition' maybe), and both wired and wireless lights would do that job. I can see lack of wires helping it be more attractive for sure, but these days most christmas tree wires are green colored to blend in and hide, and due to the fact everyone they know would have the same setup, it's not like you are the odd guy out with some weird freak setup.

Compare a $10 string of lights (Or $1-2 from discount/dollar stores) to $400 for wireless, when both perform the primary function identically, many will go for the cheapest option. Especially considering some people have no problems paying under $20/year for new strands of wires, just to avoid having to untangle them or replace bulbs. It isn't exactly a long term investment item ;}
Clearly the wireless light tree is an investment, but that still goes back to the fact not many people are in the mindset to invest in one.

Then there is the problem of obscurity.
Even I had no idea this product was on the market until you pointed it out. And I think it is awesome and would like something like this!
Most non-geeks have no such desire, thus wouldn't go looking for it, and are less likely to run across it being mentioned (such as I just did on a tech site, from another fellow geek)

I hate to say "If I didn't know about it being a geek, how would any non-geek know?" but it really feels like that.

I dunno, just thinking out loud. Those are my guesses anyway.
PS, thanks for the links! :D

Cats and hats (-1, Offtopic)

Anonymous Coward | about 5 years ago | (#28813333)

Great, but can it duplicate my hats and kittehs?

And if you're wearing a tinfoil hat (1)

Ralph Spoilsport (673134) | about 5 years ago | (#28813381)

Your head explodes!

Yay!!!

As a physicist... (5, Informative)

The Master Control P (655590) | about 5 years ago | (#28813431)

I'd like to be the first to complain that resonant power transfer has nothing to do with quantum entanglement.

You'll be getting a memo from the Tesla Death Ray department shortly; Not observing it won't save you.

Re:As a physicist... (1)

n3umh (876572) | about 5 years ago | (#28813487)

I'd like to be the first to complain that resonant power transfer has nothing to do with quantum entanglement.

Entanglement, no. Tunneling, yes... if you like to market your device by insisting on quantum descriptions of things that involve transition rates of 10^28 photons per second. A ~10MHz photon doesn't pack a very big punch, energy-wise.

It's a classical effect but can be framed in quantum terms for "welcome to the future" cred.

Re:As a physicist... (0)

Anonymous Coward | about 5 years ago | (#28815763)

As respected member of species: Ravenous Bugblatter Beast of Traal, I would very much like to disagree.

Tesla did not just assume that you could do this (1)

cwills (200262) | about 5 years ago | (#28813541)

Tesla actually demonstrated it. He just never got the chance to scale it up. So.. before going around and saying that this has just been invented, go check Tesla's patents.

Re:Tesla did not just assume that you could do thi (1)

RobVB (1566105) | about 5 years ago | (#28813925)

It says Tesla assumed it would be delivered wirelessly, meaning he didn't think we'd build amazingly expensive and ugly power lines all over the world. But you're right, Tesla did demonstrate it. That just wasn't the point of the sentence.

Re:Tesla did not just assume that you could do thi (1)

pitu (983343) | about 5 years ago | (#28814051)

any reference that he demonstrated this? ....besides his patents

Causing Cancer (1)

Nom du Keyboard (633989) | about 5 years ago | (#28813753)

Does it cause cancer yet? If it doesn't, it will because somebody will figure out some way to claim it happens.

Re:Causing Cancer (1)

schnikies79 (788746) | about 5 years ago | (#28813821)

Only in California.

Re:Causing Cancer (1)

crazzzyjoe (1605169) | about 5 years ago | (#28814011)

Well duh, of course it does! It uses science doesn't it? And we all know that science causes cancer. Always.

We already have wireless power almost everywhere (1)

Skapare (16644) | about 5 years ago | (#28814115)

... at least in good weather during the day.

Splashpower (1)

Colourspace (563895) | about 5 years ago | (#28814125)

A company I visited as an FAE back as far (actually is it far?) as 2003 (Splashpower, Cambridge, UK) demonstrated a pad that with specially adapted battery packs would recharge any handheld electronics placed upon it, without wires. I know they didn't survive. I wonder what happened to them, anyone know? I do remember their chief engineer was one of the Atari Jaguar 2 designers, so he must have been fairly used to canned projects.. Yes that's right, the Jaguar 2!

Meh. (2, Interesting)

djMouton (267156) | about 5 years ago | (#28814241)

To quote John Dvorak: "My toothbrush has been doing this for years."

(ducks)

Wireless Vehicles (0)

Anonymous Coward | about 5 years ago | (#28815019)

Why be content with a wireless light bulb when you can have wireless vehicles?

Here's a demo of wireless power transmission providing the motive power for the 'Tesla Roadster' built by Nevada Lightning Laboratory:

http://www.youtube.com/watch?v=QuAkdynoMuM

Cost hides the ineffiency hides the cost .... (1)

fygment (444210) | about 5 years ago | (#28815133)

Inefficient use of an energy resource is NOT what is needed. Even if it cost as little as wire, it delivers energy less efficiently and puts more demands on resources to deliver the energy. And, no, it will never be efficient because of the square law [wikipedia.org] .

Our problem isn't the energy consumed, it's that through inefficiency we waste resources.

Wireless Vehicles (0)

Anonymous Coward | about 5 years ago | (#28815201)

Wireless power using magnetic coupling is relatively weak; lighting a bulb with magnetic wireless systems is touted as a major achievement.

Tesla's original scheme using electric coupling is far more potent, as can be seen in this video where an electric-coupled wireless system powers a human-driven electric cart, over a considerable distance:

http://www.youtube.com/watch?v=QuAkdynoMuM

 

Where does the lost power go? (1)

Jamie Lokier (104820) | about 5 years ago | (#28815203)

If it's only 45% efficient, and powering a 20W light bulb (guessed), and apparently doesn't radiate or heat people...

Where is it dumping the remaining 55% (11W)? Does the transmitter just get hot safely?

Wireless Power is a great idea (1)

plaxion (98397) | about 5 years ago | (#28815481)

Wireless Power gives everyone a warm fuzzy feeling... oh, wait...

*sigh* (1)

davcorp (465418) | about 5 years ago | (#28815771)

Edison??? Really?? Puhleeze........!

From TF(BBC)A (1)

DynaSoar (714234) | about 5 years ago | (#28815979)

"Wireless power system shown off" [article title]

Well, that's one state necessary for a fully functional system, but I'd be far more impressed if it was shown on.

Who's going to lug around the transmitter and receiving unit (if not internal to the device) when they can stuff a thin wire in their pocket?

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