Wireless Power Over Distance: Just a Parlor Trick? 215
Lucas123 writes "Companies like U.S.-based WiTricity and China-based 3DVOX Technology claim patents and products to wirelessly powering anything from many feet away — from smart phones and televisions to electric cars by using charging pads embedded in concrete. But more than one industry standards group promoting magnetic induction and short-distance resonance wireless charging say such technology is useless; Charging anything at distances greater than the diameter of a magnetic coil is an inefficient use of power. For example, Menno Treffers, chairman of the Wireless Power Consortium, says you can broadcast wireless power over six feet, but the charge received will be less than 10% of the source. WiTricity and 3DVOX, however, are fighting those claims with demonstrations showing their products are capable of resonating the majority of source power."
this rock you rounded off is useless (Score:5, Funny)
i mean, the amount of effort it took you to make that rock round and then roll a log over it? you could have carried 10 logs in that time. quit with the making new shit, gorg, it isn't useful at all and it isn't like anyone will ever find a way to improve on it. ...
oh, nice vette, gorg.
As it was before (Score:5, Insightful)
Re:As it was before (Score:5, Insightful)
Back in the day, Tesla had achieved even greater success. Though if you can charge from anywhere, how can you be billed? That is what will permanently stop this type of technology.
Exactly.
It's not that wireless power distribution is a "parlor trick" - rather, the problem is that the profiteers are doing it wrong.
No it isn't (Score:5, Interesting)
The problem is inefficiency. Power drops with the square of distance. That means you need a bigass transmission source to get a small amount of power any distance away, hence why things like FM stations have 5 digit wattage transmitters.
Yes we have been able to transmit power wirelessly for a long time, no it is NOT practical or efficient. If you are enthralled with Tesla, spend some time reading some actual books on him, not just the silly piece by the Oatmeal. He was a fascinating man and worth your time to learn about, but you need to learn about him if you want to go spouting off.
He didn't invent some magic transmission technology we can't replicate, he invented an inefficient transmission technology that we can replicate, but don't, because he was not able to solve the efficiency problems (and it may not be physically possible to).
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Power drops with the square of distance.
Not if you have a directed beam of energy.
The beam could be directed based on some set-up protocol between the energy-source and the energy-consumer.
And you can easily direct beams by using some antenna array.
Such direction-sensitivity could also be used to (partly) solve the billing problem.
http://en.wikipedia.org/wiki/Antenna_array_(electromagnetic) [wikipedia.org]
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Power drops with the square of distance.
Not if you have a directed beam of energy.
An Antenna array is lots of antenna, and in each one "Power drops withe the squar of distance".
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Even directed beams drop off with distance squared once you get outside the near field. A directed beam is a lot more efficient than an omnidirectional beam, but for any given directional beam, power will drop off with distance squared, and narrowing the beam will require larger antennas setups.
Yes, that can be done. But the collectors are very large if you want to catch most of the power. And they also suffer large efficiency losses compared to a wire and low frequency.
Re:No it isn't (Score:5, Informative)
ever heard of lasers?
Or optical masers, as they used to be called!
how about a radio wavelength laser?
So, regular masers, then?
Okay, cool.
Now go read about diffraction [wikipedia.org], and see if you can realize that lasers, masers, etc. aren't magic, and that every finite beam loses power like 1/r^2 in the far field.
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"radio wavelength laser" ... you mean a MASER, which is even older than the laser. Won't work. Although coherent radiation does not obey the inverse square law it does suffer divergence from diffraction effects (unavoidable) which is inversely proportional to distance. Also masers and lasers aren't very efficient so I don't think this is a solution either. Face it, Tesla was a great guy but on this he was plain wrong.
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The problem is inefficiency. Power drops with the square of distance.
That's when the transmitter is essentially a point source radiating in a sphere. I have a tiny bit of experience with very high powered radars that use beam-forming to narrowly direct their transmission. In the past that sort of beam-forming required lots of bulky equipment, but apparently that's changed in the last decade or so. I wouldn't be surprised if something similar could be used to direct wireless power with much better efficiencies.
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Beam forming is just the correct use of interference patterns, and it is very useful for *information* transmission, and an useless piece of crap for *power* transmission: you still leak power like a sieve. The math is not even complex, in fact it is downright simple.
The only way to increase efficiency is to redirect the wavefront and concentrate it where you need it instead of letting all that power go somewhere else it is not useful. This means you need to *reflect* it, maybe *guide* it (using waveguide
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not buying even if true (Score:3)
Looked at one of the demo videos. There is a 4000watt transmitter (in middle of floor, nevermind the radiated power someone is gonna trip on it!) a few feet away from most of the stuff and i don't see 2000w worth of stuff.
Don't know how it works, don't care so much to look. I don't plan on adding a 4000watt transmitter to each room, seems like a half dozen power cords would be a bit cheaper. Not that i have any interest or hope for anything called 3D power...sigh.
But...Does the green carpet in the one vid p
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tesla was the genuine article: a mad genius
so there's the genius
but there's also the crazy part to
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Like Newton and Alchemy.
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I thought the resonating magnetic field solved the efficiency problem for Tesla.
These guys aren't charging the planet at the right frequency.
Tesla Worship (Score:5, Insightful)
Personally, I think the Tesla worship among geeks has gotten WAY out of hand in recent years. Yeah, I know the Evil Rich Guy Edison vs. the Poor But Plucky Tesla makes for a great literary narrative. And I don't discount the guy's work (particularly with alternating current, which he was right to argue for over DC as a practical means of long range electrical transmission). But he wasn't a god, he wasn't 100 years ahead of his time (as some recent hyperbole would have it), he didn't invent anything which subsequent engineers haven't since replicated and improved on, and he didn't certainly didn't invent EVERYTHING (the list of claimed inventions seems to get longer every year, in spite of the fact that he remains decisively dead).
I think we do him an honor to recognize his REAL work. But we do him a dishonor to exaggerate, or even mystify, his accomplishments.
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I dunno, it isn't Tesla worship: but at least his real work, good , bad, or useless, was real work, and was really his. I think Edison once pointed out that Tesla would never be great because he didn't know how to steal. That from a man who did steal, and kill, too. Seems to me that after TARP, you would have had enough of great men. If that wasn't enough, there's the quadrennial election.
Tesla's inventions may not be practical for various purposes, but they did have a use within their own limits.
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Allright...
>but he was not even known until the media started there conspiracy over his Monster Tower
Utterly false - he had a famous exhibit with Westinghouse at the 1893 World's Fair. He was quite well known at the time.
> A lot of his patents and notes have been seized and kept classified
I've heard this claim over and over. I've never seen anyone provide any proof.
Re:Tesla Worship (Score:4)
For the record, that would actually be *consistent* with the claim that his patents and notes have been seized and kept classified. If you want to debunk the claim that something is being kept secret, you have to do better than, "I've never seen it.".
I'm not debunking anything as I don't have to. Some of Tesla's personal effects were seized by the government after his death and released to his nephew a few years later. Some of his documents went missing. It's possible that the government kept and classified them. It's also possible that they were simply lost, or stolen by someone else.
Now you need some back story. Tesla was a believer in aether theory - a theory that there was undetected type of matter that energy could flow through. These theories were shown false around the same time relativity was becoming popular (Tesla rejected the theory of relativity.)
If Tesla's dreaded beam energy weapon was based on the concepts of aether theory, the possibility of it working is basically nil.
So, what's more likely - Tesla was smarter than Einstein, Lorentz, Feynman, Hawking, Hubble, and a few hundred other extremely bright guys, understood physics in a manner unknown to all of mankind, and it's dumb luck that all our modern gizmos that depend on special relativity to operate function as they should.
Or - Tesla was wrong about relativity, his beam weapon never worked, and the papers about this weapon were lost somewhere?
Tesla was a certified genius. His contributions to electrical engineering are incalculably important. That doesn't mean he was infallible.
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The problem is inefficiency. Power drops with the square of distance. That means you need a bigass transmission source to get a small amount of power any distance away, hence why things like FM stations have 5 digit wattage transmitters.
Yes we have been able to transmit power wirelessly for a long time, no it is NOT practical or efficient. If you are enthralled with Tesla, spend some time reading some actual books on him, not just the silly piece by the Oatmeal. He was a fascinating man and worth your time to learn about, but you need to learn about him if you want to go spouting off.
He didn't invent some magic transmission technology we can't replicate, he invented an inefficient transmission technology that we can replicate, but don't, because he was not able to solve the efficiency problems (and it may not be physically possible to).
Radio stations use that kind of power because they want to broadcast a signal hundreds of miles in a very noisy RF environment. True, it's inefficient but you could definitely transmit power a few feet and use the power to run some device. Charging most cell phones for example only requires about 500ma at 5vdc. Even at 10% efficiency it's doable; just inefficient.
Tv's and electric cars, though.. that sounds like a huge stretch. I wonder if the FCC has properly studied this stuff - at the transmission l
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Can't you see how crazy you sound? Smartphones are a new constant drain on electricity, and if you dropped the efficiency of the charging transmission line to just 10%, you'd potentially cost the grid GIGAWATTS of capacity.
Here are my thoughts:
Current worldwide sales of Smartphones were 154 million units in 2012 [techcrunch.com]. If they continue to grow like last year, in 2013 they will move 220 m
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He did solve those efficiency problems... Something called Alternating Current. It's gonna be big!
Of course without Tesla's work on wireless power, we wouldn't have "radio" (and various technologies) either. Marconi's famous radio patent used more than 20 Tesla patents...
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Yes, because in the 100+ years since, no one, I mean no one could ever have invented the stuff that Tesla did. There's no way that we would have radio, even today, without that man.
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If you are enthralled with Tesla, spend some time reading some actual books on him, not just the silly piece by the Oatmeal. He was a fascinating man and worth your time to learn about, but you need to learn about him if you want to go spouting off.
He didn't invent some magic transmission technology we can't replicate, he invented an inefficient transmission technology that we can replicate, but don't, because he was not able to solve the efficiency problems (and it may not be physically possible to).
Well, had you read some actual books on the topic, instead of spending your time coming up with snarky responses to satisfy your narcissistic need to baselessly denigrate others, you would know that Tesla had a solution indeed - many towers, spread strategically about the globe, creating a worldwide network of wireless power stations.
Had his brilliance been recognized at the time, we wouldn't be playing catch-up on century old technology. Let that be a lesson to the world - today's mad scientist may just
Re:No it isn't (Score:4, Insightful)
> The problem is inefficiency. Power drops with the square of distance.
Wrong!
That's how radio works.
Actually the resonant schemes DON'T use radio, they use inductance; which is just magnetic fields; and they work at much lower frequencies.
By contrast, radio is a particular mixture of magnetic and electric fields that propagate to infinity, and you tend to lose them. That was the genius of Marconi, to get the mix right.
But magnetic fields on their own don't propagate, that's partly why magnets don't go flat. The energy hangs around the transmitter and can be absorbed by a suitable receiver.
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You're correct that power drops with the square of distance, however it does not mean efficiency follows the same relation. It can be improved through resonance. This phenomenon allows the power of the magnetic field to be much higher than the electrical power put in the antenna. Think of somebody pushing a child on a swing. This works because an induction antenna does not simply send energy into space, but it sets up a magnetic field that can be recaptured and reused in the next cycle, adding up the energy
Re:No it isn't (Score:5, Funny)
I don't have any interest in carrying a phone in my pocket that's recharged via lightning bolt from the wall.
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"Sufficiently clever engineering is indistinguishable from magic, and there's fuck all in the cupboard."
L. Ron Hubbard's mother.
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Sufficiently clever engineering is indistinguishable from magic, and there's fuck all in the cupboard.
Now I remember one of the reasons L. Ron creeped me out so much: nobody ever cussed in one of his novels (people who never cuss - this includes authors - often give me the heeby-jeebies).
wat (Score:2)
.....? So how many of Heinlein's novels did you have to read before finally concluding his non-cursing creeps you out? Was it a growing sensation, a feeling of unease slowly building inside you, nibbling away at your very soul as you shifted restlessly on your seat, brow furrowed in discontent? I can just imagine you sitting there with feet kicked back in your overstuffed blue armchair by a cozy fire, suddenly shooting straight to your feet when it dawns on you: "Holy shit! Now I realize what's been bugging
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You know, I hadn't considering the fact that Heinlein never did cuss either, not since I was a teenager at any rate. Perhaps it was something about the era the books were written in; I don't believe any of the other sci-fi I grew up on (novels primarily in the 50's and 60's, primarily) contained much if any, either. Nevertheless, there was something about L.Ron's writing that was struck me as slightly off; the absence of cussing always seemed to stand out like a sore thumb - perhaps it was because his depic
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I think you have L. Ron Hubbard and Heinlein mixed up.
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How about we refuse to accept the obvious ``this will never work'' and assume that ``some clever engineering will make it work''? Wireless power transmission is not impossible... heck, lightnining is pretty damn destructive, and manages to push a ton current through the air (a pretty damn good resistor under normal circumstances)---and somehow manages to avoid that whole square-of-distance thing (once arc is established).
But efficient wireless transmission with small receiving antennas is impossible. It all comes down to geometry.
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Lightning is incredibly inefficient. Yes it pushes a ton of current...but 90% or so of the power is lost turning the air into plasma. The fact it's still dangerous at ground level is just a reflection of the truly staggering amount of power their is to start with.
Re:No it isn't (Score:4)
Yes, but what if you could induce lightning in a certain location, and then convert it into energy ?
All we need is something that can absorb the energy , and give it back at a slower rate later.
Much more interesting than wireless electricity.
The trick is to collect it before it turns into lightning. Stop it doing all that work on the atmosphere.
Superconducting helium balloons connected to clouds which discharge the current build up as it occurs gives you more manageable levels of current. The average potential difference between stratosphere and the ground is something like 300,000 V at all times, so even in clear air conditions you'd get some power.
At this point though, the volcano powerplant makes more sense.
Marvin Heemeyer or Shawn Nelson ? (Score:2)
At this point though, the volcano powerplant makes more sense.
dude, you forgot the link to your Kickstarter page!
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An under-expressed notion by the people talking about MASERs. A 100W focussed beam of microwaves might charge your laptop, but it's also going to happily start microwaving any incidental internal organs in it's path.
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... if you can charge from anywhere, how can you be billed? That is what will permanently stop this type of technology.
Exactly. ... the problem is that the profiteers are doing it wrong.
J.P. Morgan figured he'd stick with the General Electric/Westinghouse business model and eschew the more efficient new technology, as it would not provide the market needed for his copper business.
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... if you can charge from anywhere, how can you be billed? That is what will permanently stop this type of technology.
Exactly. ... the problem is that the profiteers are doing it wrong.
J.P. Morgan figured he'd stick with the General Electric/Westinghouse business model and eschew the more efficient new technology, as it would not provide the market needed for his copper business.
J.P. Morgan is, in many circles, considered one of the greatest Americans ever.
It never ceases to amaze me how much praise and adulation the people in this country can heap upon the fantastical image of a person who, in reality, was far more concerned about maximizing his own bottom line than he was about advancing humanity, and was essentially a self-serving traitor to mankind... perhaps that's a testament to the human tendency towards selfishness.
Re:As it was before (Score:5, Insightful)
Though if you can charge from anywhere, how can you be billed?
Don't worry, I'm sure you'll be charged for the amount of power sent, and not the small amount of power received
Re:As it was before (Score:5, Interesting)
If anyone went through with this kind of thing they SHOULD be charged by the power sent. It is, after all, taking that much power to charge your device. The wastage is your problem for being too lazy to plug in your phone.
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And I propose an additional surcharge of 100% for using such a ridiculously inefficient and wasteful technology.
Re:As it was before (Score:5, Funny)
Yeah, and Tesla also cloaked a navy ship and accidentally sent it back in time! And the world is run by Illuminati Lizard-men!
Re:As it was before (Score:5, Insightful)
No he did not.
Tesla needs props, but the Tesla myth does not.
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Lack of imagination seems to stop it pretty well.
I could see residential communities utilizing this complete with meters and billing.
Especially if it can be dispensed at a specific frequency.
Even without metering, the electricity only goes so far and a fair communal price for usage could be instituted based on general usage and on a flexible rate.
Hey, radio waves go everywhere, but they seem to be able to charge for XM/Sirius with no problems. Satellite T.V., Wifi, sure there are some using it for free, but
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Assuming you could make the power transfer practical, there's nothing to stop you from implementing an identification protocol over the inductive connection. Sure, it could be spoofed, but at the end of the day, *anything* can.
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Except that now the device can have chips in to measure the amount of power being supplied, and if somebody hasn't paid, can cut it off.
And actually the original problem about how you can be billed was solved by television broadcasters; mostly it relied on people being honest, and occasionally driving around with a truck with equipment to sniff out people that were stealing.
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You mean "hear, hear".
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Well what's the equation for it?
You mean like Maxwell's equations?
Empirical observations and working technology mean nothing
You mean like the metric fuck ton of empirical observations related to electromagnetism in every day life and engineering done for a huge swath of technology? I've seen people on the internet claim to found disagreement with Maxwell's equations. Although it seems really funny that things I've designed and built that would be orders of magnitude more sensitive to the various deviations they show work exactly as predicted. Some people don't realize how many things around t
unintended consequences (Score:2, Funny)
Have they tested its ability to charge the phone of someone with a pacemaker or other medical device? Sure, it charged the phone, but he was no longer around to make a call...
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Sure, it charged the phone, but he was no longer around to make a call...
[marketing] So dispense with cables and increase time between charges.[/marketing]
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Inductive charging pads (Score:3)
I think these are a great idea and I would not be surprised if Apple start to support them in the future. A phone could be built with no open connections at all. Just wireless data and inductive charging. But over longer distances the laws of physics catch up with up. Obviously the shorter the wavelength the less doffraction you get over a given distance so if you direct power with a laser and convert it into electricity with a photovoltaic cell then you could easily get more efficiency over a few metres than with induction. Maybe in the future it will be considered normal to transmit power that way.
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The Duracell Powermat make adapters for various devices, but they understandably add bulk. If there could be some wireless charging standard similar to the UK "All mobile phones charge via MicroUSB" system, we'd all be a lot better off.
You can transmit power wirelessly over distances. (Score:2, Interesting)
...but, the further you go the more it resembles eating your lunch sitting on power lines.
At the one end, there is no measurable danger in charging handset on a pad charger. But do you really want to spend all your television watching hours in a room where 200 watts of power is being beamed to your TV (and 19x being radiated) from the wall to save you the bother of the unsightly cord?
If you have magnetic wave energy, you have electric wave energy, which means you have RF. You can shape the way you transmi
What about the dangers? Does it cause cancer? (Score:2, Troll)
So I would think it would be possibly dangerous to come close to fields where energy is passing through your body. The more energy involved the worse off I'd think people would be. I don't tend to worry much about low energy fields like cell phones or wifi. Yet if a job powered all the computers with remote energy so I'm exposed all day long, I'd have to decline that job. No sense risking cancer for any
Re:What about the dangers? Does it cause cancer? (Score:5, Informative)
(Emphasis mine.)
It depends entirely on the range of course (Score:3)
Re:What about the dangers? Does it cause cancer? (Score:4, Interesting)
My reasoning is that people who live near high power lines develop cancer at a higher rate than the general populace, while people using regular electronics and in home wiring systems don't get impacted as bad.
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people who live near high power lines develop cancer at a higher rate than the general populace
[citation needed]
Propagation, Dissipation, and Inductance (Score:2)
I'm as big a Tesla fan as anyone, but I'm also a practical electrical engineer.
Someone above already raised the end-point billing issue the utilco's will have, so we needn't bother with the bean-counter side of things. MBA's, rest easy. Your obscene profits are safe.
However, going from a theoretical ability to blast x amount of joules across an air gap to capturing a useful fraction of x without frying the adjacent wildlife and neighbors is quite another thing. As TFA points out, they seem impressed with a
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There is no billing issue. Billing would be easy.
Confusing magnetic resonance and radiated RF power (Score:2)
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Chapter 4 of the ARRL Handbook (Score:2)
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What this says to me is that as long as the antennae are large you can have a decent distance. Which means that it should be great for charging cars but shit for charging phones.
Ask 'em to put another load nearby (Score:4, Insightful)
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Now THAT is actually interesting. Finally, some discussion of the practical aspects of resonant systems. I'd never heard anybody mention system detuning if there's more than one load.
I had heard about the alignment problem before, but when you're talking about most gadgets, they have an obvious antenna orientation because they generally have one particularly slim dimension and two broader ones. I'd assume you'd build the plane of the antenna to correspond to the broader dimensions, since it apparently ne
Re:Tesla (Score:5, Informative)
You also have to consider the efficiency. Running a 1GW power plant just to light a 100W light bulb a few kilometers away does not seem a good idea.
Yes, it is possible to transfer power without wires - radio has been doing it for a long time (a simple crystal radio set does not need any power other than what it gets from the antenna, but you'd better have some sensitive headphones, a big antenna and a station that is relatively close). The problem is transferring a lot of power efficiently and without huge antennas.
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You also have to consider the efficiency. Running a 1GW power plant just to light a 100W light bulb a few kilometers away does not seem a good idea.
Yes, it is possible to transfer power without wires - radio has been doing it for a long time (a simple crystal radio set does not need any power other than what it gets from the antenna, but you'd better have some sensitive headphones, a big antenna and a station that is relatively close). The problem is transferring a lot of power efficiently and without huge antennas.
Their claims are apparently that they can achieve better efficiency than had been thought possible.
Anyone who wants us to believe differently should have independently verified proof. If you suspect parlor tricks, it's helpful to have a magician involved in addition to the scientist or engineer. "Extraordinary claims" and all that...
Or maybe a bad summary? Almost 50% loss over a relatively short distance might match the claims of "majority of the power".
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I could build a (very expensive) field generator with some funky shaped field with much of the flux passing through some point six feet away. Only problem is, you'd have to stand in that exact spot.
I agree that these products are BS and/or a waste of energy. If you just think about field lines, either they all pass through your phone or they don't. If they cover a wide area, clearly most of the possible flux is not hitting your phone. Fields 101.
I suppose you could install many field generators and have the
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I could build a (very expensive) field generator with some funky shaped field with much of the flux passing through some point six feet away. Only problem is, you'd have to stand in that exact spot.
You need a flux capacitor.
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"Wireless high power transmission using microwaves is well proven. Experiments in the tens of kilowatts have been performed at Goldstone in California in 1975 and more recently (1997) at Grand Bassin on Reunion Island. These methods achieve distances on the order of a kilometer."
http://en.wikipedia.org/wiki/Wireless_energy_transfer#Microwave_method [wikipedia.org]
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Yeah and? You realize that most of the power was lost before being received over that long distance, right? Tesla didn't break the laws of physics despite what his modern-day, rabid fans would have you believe.
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"Tesla figured out how to broadcast power miles away, wirelessly, using technology available in the late 1800s. "
STOP IT. this is a false statement. Tesla went bat shit crazy, and made shit up.
Yes he was a genius and found out how to do some great stuff. Lets celebrate that and not the Bullshit myth.
I'll be impressed when you idiot can start to separate fact from fiction.
And before you replay, if such a device existed, billing would be trivial. IT's like people really ignorant of electrical engineering and
Re:Tesla (Score:5, Informative)
I'm waiting for my apology.
Re:Tesla (Score:4, Informative)
The problem with Tesla's system is the frequency on which it operates. 10 Hz has a wavelength of 34.73 meters. Properly receiving power at that frequency requires an antenna sized to match. Needless to say, it's not going into a handheld device. Tesla intended his system to be used in relatively large scale fixed installations. You could power your house with it, but the individual pieces of equipment in the house would be wired to the receiver. So yes, in theory his system could eliminate the grid as we know it and that does indeed address "power over long distances" as the headline does (really long distances). However, it's solving a different problem, that of very long distances using very large equipment, rather than the handheld gear over tens of feet as the articles are arguing over.
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I looked into that article and the guy who wrote it. The quote you're quoting comes from a book he wrote himself (although the quote is from a chapter written by some other guy.)
Unfortunately I couldn't find an online reference however, so it's impossible to know just how the measurements "Dr Van Voorheis" mentions were made. So far I've had a hard time to find any examples of people who have actually reproduced the large scale effects that Tesla claimed to achieve.
If you look for the author of the article
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If it's an isotropic antenna radiating the power, then yes... the amount of received energy decreases as a square of the distance. But tesla wasn't using isotropic antennas. In fact, he was basically using giant coils to induce current flow in the Earth's magnetic field. By coupling it to the already-existing magnetic field, he could transmit power over very long distances at low losses... but it required a very low frequency (7.8hz) and a massive amount of input energy to run the process. It was definately
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How was it lost? We know exactly the physics behind his transmitter. There was nothing magic about it.
Re:Tesla (Score:5, Funny)
Why was his info "Illegally Seized " a at the time of his death and is still not known today ?
I'm not saying it was aliens....but it was aliens.
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he didn't invent wireless communication.
look up photophone (1880)
or
David E. Hughes 1889
or
Heinrich Hertz
or
Chandra Bose
One popular comic ass talks about Tesla, makes factual wrong statements about Tesla, and every self proclaimed 'nerd' starts repeating it like it's actual fact.
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he didn't invent wireless communication. look up photophone (1880) or David E. Hughes 1889 or Heinrich Hertz or Chandra Bose
Theoretical experimentation != invention.
If it did, I would be considered one of the "inventors" of anti-gravity.
One popular comic ass talks about Tesla, makes factual wrong statements about Tesla, and every self proclaimed 'nerd' starts repeating it like it's actual fact.
Or, one popular comic ass talks about Tesla, and every self-aggrandizing asshole and his brother comes out of the woodworks to accuse everyone else knowing precisely dick about the topic.
Get over yourself, dude - some of us were Tesla fanatics long before there was such a thing as shitty web comics.
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Marconi and Braun, Nobel prize winners. Tesla was like 10 when they did this.
Is tree bark made of chocolate, in this fantasy world you inhabit?
Just curious...
Re:No difference between power and radio (Score:5, Insightful)
If you don't make your power signal directional, most of the power is just gonna leak away into the atmosphere.
This is not how these devices are supposed to work... that is to say, this is not the same as radio. It's a near-field, not radiative, effect. Most of the power that does not go into the receiver returns to the transmitter as part of the resonant oscillation (via a collapsing magnetic field.) Some will be lost to fringing, but the percent lost to that per oscillation is much lower than the percent absorbed by a properly tuned receiver, by design.
Not that I'd advocate this for consumer use, it will still be less efficient than a wire, and I'd rather see consumers suck it up and run a wire where appropriate instead of finding yet one more way to waste energy and pile ruin on our planet. However there may be some very productive niche uses.
Re: (Score:3)
no more car chargers, no more wall wart chargers, no more devices disposed of due to worn out charger connections.
make sure all are compatable, or near compatable with only variability being amperage output, clearly marked on chargers and mi
Re: (Score:2)
no more car chargers, no more wall wart chargers, no more devices disposed of due to worn out charger connections.
However this problem could be fixed without ever leaving the wired space. To some extent, it is already being fixed with USB, but for higher power devices, PoE/PoE+ might be a good thing to encourage, even for non-networked devices.
Now if we could just get them to stop changing the damn connectors all the time.
Re: (Score:2)
However if you can make a beam like transmission path the then the area never diverges your power density will never drop. I have no idea how you would even start to do this
I believe the device you're thinking of is a laser.
Re: (Score:3)
Or a wave tube. There are various things that are readily available, that will serve: for visible light, try those little fiber optic thingies. For radio and microwave, try steel pipe or conduit. For electric, try a strip of drawn copper wire, isolated with either air or polyester/pvc/nylon.