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Sony Prototype Sends Electricity Through the Air
itwbennett writes "Sony announced Friday that it has developed a prototype power system based on magnetic resonance that can send 'a conventional 100 volt electricity supply over a distance of 50 centimeters to power a 22-inch LCD television.' Unfortunately, Sony's prototype wasted 1/5 of the power fed into it and additional losses 'occurred in circuitry connected to the secondary coil so the original 80 watts of power was cut by roughly a quarter to 60 watts once it had made its way through the system.'"
But if they can't improve on 50cm, I'm just getting a 2ft extension cord for fixed items.
(sorry for mixing units)
Arguing with an engineer is like wrestling a pig in the mud. After a while, you realize the engineer enjoys it.
If you still need a cable to connect your video sources, what's the point?
But how is it different from WiTricity?
http://blogs.lns.kicks-ass.net/moonjihad/
Why is anyone wasting any time on useless technology like this? Is it based on consumer demand? If so then consumers need some basic physics and electronics lessons. This is not Star Trek, people, we can't "beam" your power to you via subspace, the inverse-square law fully applies, this is not ever going to be efficient or practical! Electrically powered things require power cords, get over it!
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
If this is a Sony technology, you better believe the electricity is going to be in some kind of proprietary format that requires you to purchase special electrons at a 30% premium over industry standard.
If libertarians are so opposed to effective government, why don't they all move to Somalia?
Yes but no but anyway you can't stop me, you whale-kissing hippy.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Only another 42,163.9995 km to go to use this to send solar power from geosynchronous orbit.
Quick! Somebody buy the Sony engineers a pair of these!
"You cannot simultaneously prevent and prepare for war." -- Albert Einstein
I'm appalled. This "prototype" isn't already perfected technology and they had the gall to send out a press release! They should just chunk the idea out the window! And please people, please stop creating this technologizma stuff because it's destroying Mother Earth.
75% efficiency is perfectly acceptable for low power devices. Making and shipping alkaline batteries repeatedly, or relying on rechargeable NiMH batteries that often leak more energy than gets used in the device, is certainly far more wasteful. So using this sort of tech to power those kinds of devices (clocks, smoke alarms, stick-on lights, etc) sounds quite reasonable. I'd certainly buy a $20 device that meant I never had to change a smoke alarm or clock battery again. In fact, 75% efficiency means it'd probably be a about breakeven powering a NiMH Roomba or Scooba versus charging their packs (in addition to leaking, NiMH isn't a very efficient charger). So you could have your home robotics never leak charge or have to waste energy charging, and never have battery packs need to be replaced, as well as the obvious "no limit on how long they can run for before needing to go back to dock".
They're going to have to significantly improve on the range, though. 1 1/2 feet isn't much at all.
Another interesting possibility would be to have a pocket-sized device powered by a li-ion battery pack. Carry it on your person and all of your portable gismos -- cameras, flashlights, cell phones, etc -- stay charged. When you get back home or to your hotel room, you plug it in to charge it. They wouldn't need as much range improvement, but they would need to make it a lot smaller than 40cm across (unless it'd be something you carry in a backpack).
Certainly you don't want 75% efficiency running TVs or charging electric cars (unless you can do it on the road, for long trip range extending -- but then you'd need some *serious* range!). But for battery-powered devices, that's fine.
I just invaded Grammar Czechoslovakia and duped Grammar Neville Chamberlain; now it's on to Grammar Poland.
Tesla was working on wireless electricity transmission but he was also working on a load of other stuff, all while baking his brain with "health-giving" X-rays. And while Tesla both claimed to have succeeded in wireless transmission and others are purported to have witnessed it, he never once made a claim as to the efficiency which, based on the efficiency of a lot of his other inventions (70% [RMS] for AC, >80% for a coil) was never higher than what Sony's come up with here.
one side of the tech business is actively thinking "hmmm fossil fuels will be running out, WTF are we gonna do" whilst the other side goes "WOOOOOOOOOO! Wireless power! PARTY ON!"
Don't be a doofus, this is a prototype. It's not like they're releasing it for mass consumption. Besides, who says we can't have wireless green electricity. The only thing NOT green about this is where the electricity comes from. Who gives a shit if it wastes 1/5th of the power if all that power comes from solar panels. There are plenty of nasty false dichotomies in the public sphere (nature/nurture, democrat/republican) we don't need another one. Don't be a doofus.
Does this sig remind you of Agatha Christie?
You'd be hard pressed to measure the line loss of a standard copper wire over two feet. It's probably like 99% efficient, if not higher.
I'd certainly buy a $20 device that meant I never had to change a smoke alarm or clock battery again.
What happens when the power goes out? Does the $20 dollar device have a battery?
On the Oregon Cost born and raised, On the beach is where I spent most of my days
The wasted energy is most likely dissipated as high frequency RF energy. In most primary/secondary coil designs (for the less enlightened... think Tesla coil), the bulk (80-90%) of "lost" energy is dissipated as high frequency RF. The rest is dissipated as heat and light.
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Indeed, just because this early prototype has 75% efficiency we must assume that the maximum that can ever be achieved. Best to just stop investigating it instead of working on improving the range and efficiency. After all scientific progress has advanced quite far enough hasn't it?
God forbid that we improve this technology and use it to replace other sources of loss to reduce energy consumption! After all we are rapidly moving towards an electric infrastructure for vehicles, and they are always this close to the road. Imagine just how bad it would be for global warming if we replaced batteries (and their associated losses) with this technology. Evil scientists.
Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
What took us so long?
Do you have any idea how much power is used to actually produce that few inches of wire? Doubtfull as it may be but systems like this may end up saving energy in the future. Even if they are not 100% energy efficient. Imagine how much money/energy would be saved if you never had to wire a house in the first place. Or if we could actualy get a wireless transmission system. Those telephone polls don't grow on trees.... Get a clue
Every new house is required to be wired for smoke detectors.
Perhaps every new house, but mine certainly isn't. I have to change the 9-volts regularly.
Honestly, I can only think of one application where not needing a power cord for a 50cm distance is all that helpful:
Take a walk through your house some time, and look at every last little gadget in the house, and count how many batteries (replaceable or rechargeable, embedded or removable) you find. I bet you'll be surprised.
a "charging pad" to recharge your mobile devices by just setting it on the pad, without having to mess with wires and connectors. However, I don't think this is likely to happen for a long, long time
Huh? That's already here. And inductive charging has been used in electric toothbrushes for ages. The difference for this is that you actually have range.
I just invaded Grammar Czechoslovakia and duped Grammar Neville Chamberlain; now it's on to Grammar Poland.
A typical lightweight power cord is 16 AWG. 60 Watts (assuming good power factor correction) is 0.5 A. 16 AWG wire is ~ 4 mOhm/ft. So 4 ft of wire (2 ft cord, supply and return) is 16 mOhm. That means you're losing 8 mV of your supply voltage, or 4 mW of power. That's about 99.993% efficient.
You have to get significantly longer extension cord and put a lot more current through it before the power loss is relevant. Even if you used a 12 ft cord, and drew a rather significant 4A, that's still only 1.5W out of 480, or 99.7% efficient. And most extension cords are 14 AWG or thicker.
nothing, it uses magnetic resonance, like an MRI machine. Are your hands magnetic?
Forget the Sony jokes for a minute. I can think of a great use for this technology : recharging smartphones!
Essentially, if they can miniaturize the receiver coils sufficiently enough, you could pack them so that they are integrated inside the batteries used in a smartphone. (yes, yes, it is somewhat inconvenient to swap the battery in certain Apple phones...)
Imagine the possibilities. You could have one of these transmitters in your car, plugged into the cigarette lighter and stuck between the driver's seat and the cupholders. Another could be on top of your nightstand in your bedroom, or wherever you tend to toss your keys, wallet, and phone at the end of the day. A third one would be in your office on your desk.
If the range is enough (100 centimeters or so) your phone would get recharged while it's still in your pocket! You'd never have to remember to plug it in, and you would be able to use the various power sucking features (games, turn by turn GPS, etc) all you wanted and would almost never run out of battery. It would neatly solve the battery problems with the current generation of smart-phones without having to make the phones bulkier or heavier.
Problems :
1. The receiver coil might take up too much space inside the phone.
2. The range might not be 100 centimeters due to various scaling laws
3. The electromagnetic charging fields might cause biological tissue damage, making it dangerous to use while in your pocket. It might interfere with pacemakers.
4. The fields might wipe credit cards or interfere with electronics in your car or office.
But if these problems aren't that bad, or can be avoided somehow, it would be great!
Nikola Tesla invented wireless electricity transfer at the turn of the 20th (yes, 20th) century. He was trying to prototype it by constructing what was called the Wardenclyffe Tower. Of course, everyone during that time thought he was a nut and the funding ran out.
Tesla is a candidate for the title of "smartest person who ever lived," and without him we probably would not have alternating current, which probably means we would get zapped much more often from our PCs (or "PMFs", i.e. Personal MainFrames). Now, considering the way society neglects its heroes of innovation, just watch Sony finish this and claim to have brought "wireless power" to the world, without ever having mentioned Tesla. "Oh yeah, him? Well we figured this out on our own. We just read a lot of these old books on magnetic resonance and pieced it all together. So smart is we!"
>>>75% efficiency is perfectly acceptable for low power devices.
Then how come the EU and U.S. are banning incandescent bulbs? The latest prototypes using laser-carved filaments operate at just 20 watts, and make the same light as a 15 watt compact fluorescent light. So that's what? 75% efficiency? And yet this is considered unacceptable by the politicians.
I say, if the bulbs are banned for inefficiency, then so too should these over-the-air power transmissions (for the same reason).
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
Hmmm, let's see: "electricity through the air." Where have I heard that before? Oh, that's right. Lightning.
One "Aw, Shit!" is worth 100 "Ata boys!"
All this "broadcasting power" stuff is not going to fly.
All the schemes that have been tried by Tesla and latecomers don't have a chance. Either they're spewing out energy, which goes down in intensity as the square of the distance, or they're like Sony, and making big air-core transformers, where the fields go down as the CUBE of the distance. You'll notice it takes a 40cm coil to send power 50cm. And so on.
Then there's the problem with all the scattered energy that does not end up in the receiving device. We're talking many watts of power. Microwave ovens are only allowed to leak a thousandth of a watt-- no national safety agency is going to allow ten thousand times that much power wandering around our houses. Yes, the power couples somewhat weakly to flesh, but it's still a lot of power to be bathing in 24/7.
What happens when the power goes out? Does the $20 dollar device have a battery?
Don't worry. The power never goes out in a fire.
is hardly enough distance to reach more than 2 shoulder-to-shoulder people in a crowd. the govt's gonna want better range, and probably higher wattage, before they consider this for crowd control.
"To stop the terrorists."