Cool!
http://www.cnn.com/2009/TECH/09/02/wirel ess.electricity/index.html
Wasn't this what Tesla was working on?
Is this a spin off from his research?
http://www.cnn.com/2009/TECH/09/02/wirel
Wasn't this what Tesla was working on?
Is this a spin off from his research?

Comments
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.
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.
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.
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.
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
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 !!!!
Tesla was more interested in transmitting large amounts of power of long distances. It wasn't radio frequency resonance, it was magnetic. Also there is no proof that his ideas actually worked for anything practical, other than his claims.
A reasonable overview: http://electronics.howstuffworks.com/wi
Health wise, the unwanted energy transfer is probably less than wifi and cell phones,
Why do wifi and microwaves operate on the same 2.4ghz band?
That band is adsorbed by water, making it fairly useless for long range use,
The MIT work looks like its related to "evanescent wave coupling".
http://en.wikipedia.org/wiki/Wireless_e
The MIT work was at 9.9mhz. I'm not sure what other than
CB radio operates in that area.
One of the worst Ideas yet.
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.
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.