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Cordless Electricity?

Cool!

http://www.cnn.com/2009/TECH/09/02/wireless.electricity/index.html


Wasn't this what Tesla was working on?
Is this a spin off from his research?

Comments

( 12 comments — Leave a comment )
(Anonymous)
Sep. 2nd, 2009 05:05 pm (UTC)
Cordless Electricity
In my mind a huge waste of electricity.
Second, a huge exposure to wireless signals and radiation.

The wireless electricity has to travel through air which is a higher resistance than plain copper. Besides, placing your 'laptop', say, too close to the transmitter, may give it an over charge, while taking it away from the transmitter too far, may cause it to have too low voltage to operate.

The wireless range of this is really small, and at this moment a matter of inches (often where the transmitter is inside a pad, which one can place his or her laptop on.
As far as cars, it really makes no difference at all, you still need to get within a few inches close to the wireless receiver with the transmitter, so it won't make any difference to just plug in the vehicle,or bring a wireless device within the vicinity of a few inches off the vehicle.

For laptops the loss in electricity may be as close as 20% (meaning your current 100W power brick might need to be replaced by a 120W one, unless the wireless pad is large, which in that case would take up more space than most modern digital powerbricks.
(Anonymous)
Sep. 2nd, 2009 05:26 pm (UTC)
Re: Cordless Electricity
Either this or increase the range of the wireless power, which increases the radiation and Magnetic field.

The magnetic field might be the same density as Earth, but the amount generated if going into mass use, it will add up over the years. Basically we will all be living under a giant electric power lines radiating magnetic field and we know how people living under such constructs are really faring healthwise.
(Anonymous)
Sep. 2nd, 2009 05:22 pm (UTC)
Wireless electricity?
uhhh, is not all energy and vibrational frequencies in the universe quote-unquote 'wireless' in nature? We are the only species in the galaxy that forces energy to be on a wire... And yes Tesla did this work at a much higher level and was character assassinated by J.P. Morgan & Edison Electric when he wanted to give it away for free. His conscience would not allow him to put a meter on peoples homes and charge them for something that Mother Nature provided throughout the entire cosmos, essentially for free!
(Anonymous)
Sep. 2nd, 2009 05:30 pm (UTC)
Re: Wireless electricity?
Yes but we will be creating more of these energies at higher intensities to satisfy power needs. Artificial creations without a balance damages nature, not help.

Reports of Bees might get extinct in 10 years due to too much wireless radio signals which mess with their navigation system are coming out. That one alone will damage the ecology, thus nature, and then us. So let us increase more radio signals beaming with electrical powers.
(Anonymous)
Sep. 2nd, 2009 05:49 pm (UTC)
Re: Wireless electricity?
With 10 families in one apartment house, each having 4 members. Each having a laptop and cellphone, all charging. You would think that if you were standing on the ground and touched the building, you would turn into a light bulb.
(Anonymous)
Sep. 2nd, 2009 05:52 pm (UTC)
This technology certainly has its applications - for example where wires are not feasible for whatever reason (in the toothbrush example it would be more expensive to water-proof a toothbrush with wires). However, the health effect may be a big concern. A cell phone wireless transmitter is only a few watts and there are already concerns about its safety (the issue is still debated). A LCD TV is hundreds time more powerful.
We should not forget that our nerve system is based on electrical impulses and large percent of our body are polarized molecules (water, proteins, etc.). Strong electromagnetic fields do not bode well with us. In fact, there is a reason why doctors have limits on the number of MRI per year. In lab experiments strong electromagnetic field erased memory in mice.
As for wireless power transmission over long distances there is a commercially available alternative - lasers. Because of their higher frequency they can transmit a lot of power over a great distance. Poor birds that got into the beam, thought...
While I can see this used in the field where the field is directional and safely isolated (like the current transmission lines), or in small distances where the field is weak (toothbrush) I certainly do not want to cross a 100W beam every time I pass by my TV set.
(Anonymous)
Sep. 2nd, 2009 06:08 pm (UTC)
A cordless future for electricity?
Tesla indeed succeeded in powering devices at significant distances without wires -- it's called radio! The MIT resonant transformer idea is just as old. And "power pads" are just 1/2 transformers -- the other 1/2 (winding) is in the device to be powered -- also old news. Remember '50s inductive stove tops that required metal cookware?

Now for reality, power density is what it's all about. A radio/TV transmitter needs to disperse its power, maybe 50,000 watts, around a wide reception area, ending up as microwatts at each receiver. A microwave oven needs to focus it within a cooking chamber that also contains a resonant receiver -- water molecules. A Mars rover needs to focus its radio waves at this small little spot we live on, so our huge receiving dishes can get something useful in the way of weak electromagnetic signals that represent data/pictures.

Power density is also what damages living things and other electronic devices, so blindly thinking that dumping wires is good, is actually dangerous. As the early DEW-Line technicians and medics discovered when standing in front of our anti-Russian-bomber radars in the Arctic -- their internal organs got cooked, even at 40 below outside.

For decades, poor people in slums have used old flourescent tubes for their lighting, by attaching a long antenna wire to pick up power from nearby high-voltage power lines. Wireless power is simply the use of the electric and/or magnetic field components produced by any electrical device, even if it's not designed to be a transmitter. That's one of the oldest eavesdropping techniques.

Bottom line is that whatever electrical energy is radiated and not received by an intended device is wasted, creates interference, damage, or worse, becomes a health threat. Wireless "electricity" is just radio waves, or "near-field" coupling, all which contain both magnetic and electric components -- see Maxwell's Equations, if interested. It's a solution to only some very restricted problems.

But, like all techie media-fluff stuff, it sounds good, but may not taste great.
;]
Dr. Alex

(Anonymous)
Sep. 2nd, 2009 09:20 pm (UTC)
Tesla...
Yes...Tesla had this idea. It is nothing new. It just never was developed. Now that no one really cares about the health of the general public as opposed to making money...the idea will probably take off.
(Anonymous)
Sep. 2nd, 2009 10:09 pm (UTC)
Cordless Electricity
Isn't this going to be pretty inefficient??
The power loss from converting to magnetic fields and back again is pretty high in induction coils. We even use that to effect in our circuits. How much power loss would this method of power transmission cause. I thought we were going to come up with ways to save energy. Not use more !!!!
(Anonymous)
Sep. 3rd, 2009 04:28 am (UTC)
A huge huge huge mistake
There's a reason that no one went forward with Tesla's designs for wireless electricity: Massive EMF exposure. You think cancer rates are high now. Just wait until they institute this! Deadly. Live under a power line and and transformer and tell me if you don't start developing strange illnesses.

One of the worst Ideas yet.
bobbyglide
Sep. 6th, 2009 12:50 pm (UTC)
Tesla
I've read some of the replies you've gotten to this-interesting. Tesla's system of wireless energy dispersion used the magnetic field of the Earth as a kind of energy "bank" that he pumped huge amounts of power into, and the power could be "withdrawn" by anyone providing their device was set to the same frequency of cycle. Tesla claimed that power transmission of this kind was completely safe and was conducted at virtually 0% loss. Currently in our homes, the copper wires in our walls lose quite a bit of electricity (almost 7.5% including the trip from the power plant to your wall socket), and they generate a magnetic field and give off low levels of EM energy. I think the safety concerns of a device that operates in a magnetically coupled system like the one demonstrated are nil. They are essentially the same magnetic forces we are subjected to constantly by the Earth itself. The power is transmitted only to devices that are set to resonate at the same frequency. Therefore, there is minimal loss of power during the transmission cycle. The same almost 7.5% losses apply to the existing energy transmission by wire from the grid to your home, though.
It's a shame Tesla was not allowed to realize his vision in this regard. Had he, the world would be quite different now. Imagine a world with free power, harvested from the sun and transmitted around the globe freely without loss- that was Tesla's dream. Of course, the rich and powerful wouldn't much like that.
(Anonymous)
Sep. 9th, 2009 12:14 am (UTC)
Recycled technology
Every decade or so, some lab tech at some college will propose a Tesla idea as original thought.
Back in the 60's I built a transistor radio that was powered by the RF it received! Yes, it worked, but it was impractical to implement. It required a long antenna and earth ground, not portable...
Unless they can void the rules of physics, it is an impossible goal, and it drove Tesla mad in his old age.
( 12 comments — Leave a comment )

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