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Wireless Power Consortium Pushes For Standard
Slatterz writes "We've already heard about wireless power before, but now we're a step closer to throwing away our power cables and chargers. A consortium of eight companies has launched an
initiative to develop a wireless power standard. The drive was announced at the first Wireless Power Consortium conference at the Hong Kong Science Park yesterday. Most consumer electronic devices require a different charger, and the resulting tangle of wires and bulky devices is 'ugly, frustrating and inconvenient to use,' the group said. 'Wireless power charging takes away the need for wires and connectors. You simply drop your mobile phone, game device, electric shaver on the charging station and the battery is recharged,' explained Satoru Nishimura, senior manager at Sanyo."
Wireless power is only practical in short ranges anyway. With standardized cables I wouldn't have drawerfuls of power cables.
...but that might not be such a good idea.
How can I believe you when you tell me what I don't want to hear?
The Wikipedia article talks about efficiencies between 40% and 80% for near field transmission. Indeed, that seems like a serious waste just for the convenience of not having to plug in your device...
FYI, far field transmissions using microwave can reach an efficiency of 95%, but I don't think you want such a beam in your house :-)
Wireless power covering an entire room will have to wait until wireless devices' power requirements go low enough that the radiated energy won't be a hazard to the user. At the power levels currently used by laptops, the power source would have to emit enough energy that you would microwave-cook the user. The device described in this article is probably using short-range magnetic coupling, not radio waves; not a particular threat to health, but putting your laptop on top of the charger would probably scramble the hard drive.
Isn't this "wireless power" stuff just a terrible waste of energy?
Transformers (not the Hasbro sort) are basically two adjacent coils, with the difference in the number of windings on each side determining the voltage step-up or step-down.
Here you have what is basically a transformer, just with the coils moved further away from each other. A 1:1 step ratio in a transformer is pretty efficient.
You're not wasting electricity spraying electrons in the air like a water sprinkler, there has to be a circuit before potential can be moved from one coil to the other. Electronics can keep idle current to a minimum. Where's the problem?
Do not mock my vision of impractical footwear
There are other advantages.
Your ad here. Ask me how!
For my Masters Thesis, I designed a wireless powering system for a fully implanted bio-monitoring device for a mouse running around, untethered, in a cage. Now, a mouse is actually quite small, so our implant had to be about the size of a U.S. dime (actually, a bit smaller). The mouse was never more than a few cm away from the cage floor, but could move around, stand up, roll over, etc., so we could not make the powering system very "directed" in nature. As a result, our optimized average power coupling efficiency we near 0.08% (Page 25, specs on Page 95), which was actually pretty good for the application. It did mean that our implant needed to be extremely low-power, however, involving all sorts of power supply optimizations (Chapter 3), MEMS sensors, and the like.)
The problem with trying to power your wireless devices anywhere in a room is similar, due to the fact that you can move around and change the orientation of your devices. As the ratio of power-receiving-antenna to "cage" is even lower, you are likely looking at even lower power efficiencies. Yes, you can perform all sorts of fractal antenna optimizations and the like, but, if you want to be able to receive power anywhere in the room, then you are limited by the laws of physics: If your powering system covers the whole room, your efficiency is limited by the simple ratio of the area of your receiving antenna in the plane parallel to the floor (or wherever you place your powering system) to the area of the powering antenna itself.
The recent demos of wireless power by Intel and others have all involved highly directed powering antennae, where moving the receiver even a small amount cuts off the power supply. Directed power does have its uses, however. Imagine medical implants that can be powered in a short time by placing a directed antenna on your skin each morning, or even wearing a battery pack on your belt with a directed antenna to power a device with a built in radio communicator. No (highly infectable) wires penetrate the skin, no surgery is necessary to replace batteries that run low, and, even in the worst cases, you should still be able to remove the battery back for a time to perform certain functions (exercising, bathing) without losing device functionality.
>> Standing on head makes smile of frown, but rest of face also upside down.
You can't develop a standard if you don't have similar technologies, and wireless power developers so far have been coming up with all kinds of different technologies. Remove the part of TFA that makes no sense in light of this, and you end up with an advertisement for this "consortium" disguised as a press release, faithfully and unquestioningly reproduced by PC Authority. Had PC Authority tried to do real journalism rather than simple reproduction, they'd have found that not only are the major proposed schemes so different that the idea of standardization is ridiculous, but that some of the members of the consortium aren't even developing any of those schemes.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
Intel chief technology officer Justin Rattner demonstrated a Wireless Energy Resonant Link as he spoke at the annual Intel developers forum in San Francisco yesterday.
Rattner demonstrated this by causing his ears to light up at 60 watts of power a yard from a power transmitter operated by his assistant Igor. Only four journalists were incinerated when the power earthed through them from his fingertips.
Rattner reassured us that pumping kilowatts of power around the home through magnetic induction power is absolutely harmless. "The human body is not affected by magnetic fields," he said as one journalist with a pacemaker collapsed and another with a knee replacement watched his leg catch fire. "There's no danger whatsoever from it, any more than there is from mobile phones cooking your brain, microwave leakage blinding you, chemical waste unraveling all the DNA in your balls or statistical clusters of kids with cancer wherever high-tension power lines run overhead. Asbestos and thalidomide were horribly slandered in their day too."
"Of course, Nikola Tesla did it first in 1899," said enthusiast Albert Tedious-Anorak, 54, of Little Boring. "I detailed this at length on Wikipedia, but they refused to believe the value of my revelations on this matter due to a conspiracy of Edison fans amongst the site administrators."
http://rocknerd.co.uk
On the other hand, MIT has managed to produce wireless power at 75% and even 90% efficiency, either of which would be more efficient than your laptop's power pack.
The details are trivial and useless; The reasons, as always, purely human ones.
FTA: 90% efficiency when three feet apart?
I've got a cold fusion rector you might be interested in...
No sig today...
So tell me - how far are your mouse, keyboard, and monitors from your desk?
The perfect use for this, in my mind, would be to have it built into your PC case. PC case sits under your desk, and monitors, mouse, keyboard, speakers are all just free standing. Awesome for LAN parties (assuming separate power transmitters don't interfere with each other), the worst thing about moving a computer (or even having one set up somewhere) is the spaghetti nest of wires tying it together. Of course, I'd probably duct-tape some tinfoil lining into my lucky rocketship underpants...
As for efficiency, I'd presume that the efficiency they're talking about is just that of the wireless transmission. There'd be a transformer at each side to get the voltages correct so it's still going to be less efficient overall than your power brick. A more apt comparison would be the 90% @ 3 feet compared to the power loss over the wires from the power brick to the device.
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.