resonance is important only on transmitter, because if nothing eats its energy transmitter can take it back from magnetic field. however without use of superconductor coil this is doomed to have terrible losses.

receiver can be any resistive loop or any non ideal conductor material, so this will heat human body as well.
and you risk to damage sensitive electronic equipment if you move it to close to the transmitter.

Yes you could create witricity at home but you would need something that makes oscillating currents in 9-10MHz range.
They used a “standard Colpitts oscillator with inductive element in a single loop of copper wire 25cm in radius” and this coil was inductively coupled (like a transformer) with the transmitting self-resonant copper coil.
On the other end is the same setup in reverse: a receiving self-resonant copper coil and next to it an insulated wire loop with an attached light-bulb (see the picture, there is the insulated wire with the light-bulb).

I think the biggest challenge is to make the coils resonate. You will have to calculated the proper geometry using the formulas they give in the paper.

With the demonstration as showed and the article readily available it should be possible to build the system yourself, the set up is really elegant and seems simple… Hey I actually got enough education understand what they are talking about and to try this at home when I got some time to spare (Sadly, I don’t)

@Jackson - It is a very good question! Ed, you want to take this one? I hear you like the equations

The mathematical models and the experiments were limited to only two self-resonant coils. But theoretically any number of objects can participate in “strong coupling” as long as they are on resonance.

“Would a heavy load on one ‘receiver’ pull down the others?” - I don’t think so because for each “source< ->device” coupling there is a finite maximum of power transfer that depends on the geometry and size of the source and the receiving coils.

If you like math and physics here is a PDF of Prof. Marin Soljacic’s original research paper from 2006 where he presents his idea for the first time - http://arxiv.org/pdf/physics/0611063

Yes, you are right, the research paper is riddled with the math equations and I had a really hard time with them.

As far as the importance of this work… well it is still too early to say anything for sure. They experimentally proved their theory and were able to get decent results but the 40% efficiency is very low. The Japaneses work was at >80% and frankly I like their solution a lot more - very elegant indeed.

So (and I have no bearing on this), how important and practical do you think this actually is?