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Well, I'm glad that you're finally trying. However, you still have problems of non-applicability, and have introduced spherical cow problems. To be blunt, in theory, there's no difference between theory and reality. In reality there is. Oh, and I'm quite up on my physics, and they don't say that I'm wrong. I may not be an EE, but I'm still STEM. So you can drop the credentials fallacy.

Next, I'll point out that you're strawmanning my(and my cited article)on the actual efficiency. The article, and I, have at most said "as efficient or possibly more". You immediately dropped the "as efficient" to argue against more efficient. To meet "possibly more", all you'd need to do is find a fairly inefficient corded charger. A cheap one, not properly optimized for efficiency.

All I've been arguing is "as efficient".

Still, you might want to read your links to make sure they say what you mean. For example, your first link says this:

But, ferromagnetic materials like steel as core of transformer, suffers from hysteresis loss, eddy current losses. Also it faces problem of getting saturated after certain level of magnetization. But these can be avoided in air core transformer as ferromagnetic core is absent in this transformer.

Looks to me like they're saying the opposite of what you're asserting. In specific circumstances, air core transformers can be more efficient than steel core. Thank you for providing more proof for my position.

Second link, continuing on from slide 5, at slide 8 they mention that increasing the dimensions of the transformer increases the coupling factor, and I can clearly see the charts showing a factor above 0.95, where 1 would be a theoretical ideal coupler ratio.

Given that one of the points I've made is that inefficiency is noted on the wiki page for under 100 watt applications, presumably with a coil around an inch across, while EV class induction coils bust the 5kW where it isn't a problem anymore, and are closer to a couple feet...

So congratulations, citation 2 also supports that a nice large open core induction coil can realistically be efficient enough for the cited charger efficiencies. You'd almost think that the businesses designing them put engineering work in.

Still, let's look at what wikipedia says about magnetic cores.

In some cases the losses are undesirable and with very strong fields saturation can be a problem, and an 'air core' is used. A former may still be used; a piece of material, such as plastic or a composite, that may not have any significant magnetic permeability but which simply holds the coils of wires in place.

What is this in reference to? Losses from eddy currents, hysteresis, and high field strengths causing saturation. What might we be seeing at 5kW and up? Why might we NOT want losses?Sounds like a potential application for an air core to me.

Citation 3 is really irrelevant. It isn't even a good explanation of coupling factor for laymen.

Noticeably lacking from your citations is that iron core is always better than air core.

Also, I reject your contention of misaligned coils, as quite a lot of development work was done to prevent that little problem.

SAE International -93% efficiency, grid to battery.

Notice that I'm posting, not theoretical stuff, but actual produced hardware, documentation about inductive EV chargers, not theoretical stuff.

Oh, and I just noticed. You're attacking a strawman. I didn't say that an air core transformer is more efficient than steel core. If that was true, we wouldn't use steel cores. Though some of that is about cost too. I'm looking

There are other gotchas though such as what if stray pieces of conductive material get in the way? If the vehicle is going to actually charge at a reasonable rate then some stray piece of metal can be a real problem in terms of picking up energy and heating. You could carefully monitor the power on both sides but it's hard to say if the difference is going to heat something. Another is broadcasting all kinds of errant emissions. When you broadcast that much power even little screwups like not parking in the exact right spot or minor damage to the bottom of the car could create tons of unwanted noise at all kinds of frequencies.

You included the key word in your own text. Broadcasting is specifically what they are not doing. Everybody agrees that a purely radiant broadcast is a terrible way to move power wirelessly. That's why WiTricity intends to use resonant antennas, as described here. That prevents both heating of stray objects, because essentially no stray metal objects will be the right size to resonate, and prevents broadcast noise, because very nearly all the power is confined to the near field.

That said, I doubt its only 10% loss...

According to the WiTricity FAQ the efficiency can be quite high:

Q: How efficient is WiTricity technology?
A: The power transfer efficiency of a WiTricity solution depends on the relative sizes of the power source and capture devices, and on the distance between the devices. Maximum efficiency is achieved when the devices are relatively close to one another, and can exceed 95%.

What "relatively close to one another" means, how big the marketing sauce on that is and if it still works with other conducting items with 1 km radius remains to be seen.
My own limited knowledge of this stuff tells me this could work. High frequency usually helps with transmission efficiency and resonant coils help a lot too.
The WiTricity site mentions near field transmission. I can't find the exact frequency, but I'll assume that it's the same as their phone charger frequency (which is in their white paper): 6.78 MHz. The wavelength in meters for that is 300,000,000/6,780,000,000= 44 meter. The near field is up to about a wavelength in distance, so the near field for this should be up to 44 meter. I have not enough experience to say much insightful about the efficiency drop off inside those 44m.

The near field Witricity technology can transmit power over a meter or two. Even further with passive repeater antenna which can be disguised as picture frames, table-mats etc.

It's a much better technology than the simple induction pads that you put your mobile phone on and could be quite revolutionary. It seems they have recently released development kits too, so hopefully it won't be too long before its generally available.

I designed one of these systems years ago in a theory paper. Basically I took a lot of ideas from Star Trek, gave it 2009+ technology, and wrote it for a graduate marketing class because I figured I could confuse everyone enough that I would be forced to get a decent grade. Not that grades matter but I had a game theory course the same semester that I wanted to learn more from and needed a fluff filler.

Concept was basically reproducing everything a Majel Barrett ST computer system could do. I started small, voice activated locks, windows, lights, and simple "Siri" inquires (pre-Siri mind you). Step 2 in development would incorporate moving things like the windows, auto-sensor doors (would help with moving days!), and add in different users. I wanted to add in people tracking based on IR or whatever so you can locate people inside the house or you dog. Even say "Computer, I put my keys here" and it would know exactly where and would be able to track where they went if it fell when you either lose of them or half-assed put them on an unstable surface. Add in a remote diagnostics if a unit doesn't work. Add in iOS / Android add-ins. This was before the iPad I think. I designed a tablet that also would be wall mountable and integrated / hung up somewhere. Don't think iPad, think LCARS. http://en.wikipedia.org/wiki/LCARS

I also did a research study (surveymonkey) of gamer / tech people.. which I think was the main point of the assignment (data analysis) but I had fun with it. So I have some hard data on what that market segment would jump on.

I didn't patent anything frankly because I'm not in it for the money and I'd rather see it be done. (though if a 2012 650xi shows up at my door one day, I'll be appreciative)

Here are some problems;
You need an OS. I like Android because it's open and I don't like Android because it's open. Don't mod my stuff... at least at first. Once you buy the system, you can blow your house up, whatever. Just keep the brand name out of the news. Also open for a linux / unix platform language... maybe even assembly. It might need a new language, unfortunately.

There are problems with the given technology. Power, data bandwidth (2009.. G was big, N was semi there, AC was a dream), OS, security, and integration. I was young an nieve.. I mentioned a possible backbone with Intel Light Peak for 10gbps.

Power was easy. Hook up with my pals from CMU who can take care of the wireless power problem for a full wired system. I did a mock up transmitter like a modded Glade plugin with a witricity emitter.
http://www.witricity.com/

Data is now easier. At one point I mentioned an integrated circuit board for drywall to have a smart wall or something to pass data. Internal transfer conduits (interlocking so you really don't need nails and quicker to assemble a room) or something like a built in wifi repeater to completely bypass the problem with signal loss. I think I mentioned I needed more review of safety standards and requests from construction workers / engineers to see how to improve drywall and make it smarter. Those guys work their asses off... yet they shouldn't in 2012. That turned into some side project that never took off.

Security. I was stumped on this. What stops Joe blow from saying "LOL CALL TEH COPS" or a robber saying "CANCEL POLICE CALL". Three years later... two level of security code. Authenticated / recognized users would need to say a PIN (Mac OS X elevation, anyone?). There were two PINs (can add in more but two in function. Like 5 safe passwords and 1 omg emergency password incase someone overhears you). One was normal and another was emergency. Meaning if I call the cops, robber puts a gun to my head and says cancel it, I can fake-cancel the call with the Panic PIN. Meaning the computer will say it "cancelled" the call but will make a notation. Sort of like if the banks really gave a shit about your well

Inductive charging is a good idea, but there are at least three competing standards, which is why it isn't going anywhere. If the industry would settle on a standard and get business hotels to put a charging pad in hotel rooms, this mgiht get deployed.

Personally I would love to see more wireless charging electronics with a single home base station. Heard about them a few years ago but no economical applications yet.

There is this. Yes, the applications are not mainstream yet, but it appears to me as though these guys are open for business and ready to go, they're just waiting on clients. This is /., if we had to wait for marketing/finance approval for every interesting new thing, we'd be reading a Sharper Image catalog.

Is it me, or are people having a hard time believing the technology actually exists?

Two Companies Already Have Products:

http://www.powercastco.com/
http://www.witricity.com/

NY Times Covered this stuff in 2007

http://www.nytimes.com/2007/12/09/magazine/09wirelessenergy.html?_r=1&ref=magazine

Here's CNET demoing powercast's tech in 2007!
http://cnettv.cnet.com/powercast/9742-1_53-25606.html

You can buy full blown evaluation boards online that powercast manufactures that implement wireless electricity:

http://www.futureelectronics.com/en/technologies/development-tools/rf-wireless/Pages/9660812-P1110-EVB.aspx

Why is everyone having such a hard time with this concept?

I saw a demonstration of this from MIT students. I'm pretty sure sony bought it, not developed.

Video
http://www.ted.com/talks/eric_giler_demos_wireless_electricity.html

Site
http://www.witricity.com/

• Radiative transfer: send a directed beam of energy from a source to a receiver. The advantage is that this can work over long distances, the disadvantage is that you need to either have fixed locations or some active tracking system to keep pointing at the receiver as it moves around, and you need some kind of automated kill switch to make sure you don't accidentally fry anything that walks between the transmitter and receiver or waste power when the receiver is not there. It looks like PowerCast and PowerBeam fall into this category.
• Traditional inductive, non-radiative power transfer. This works well, and does not transfer power when the receiver is absent, but is extremely short-range if you want any kind of efficiency; typically, the device to be charged must be sitting directly on or adjacent to the charger. The Wireless Power Consortium is pursuing this kind of approach.
• Resonant, non-radiative power transfer. This relies on the source and receiver being electrical resonators at the same frequency, so that they preferentially transfer energy to one another rather than to other objects in the environment via resonant coupling. This is the approach being pursued by WiTricity, where they additionally rely on resonators that couple primarily via magnetic fields (the electric-field energy is mostly in capacitors inside the devices), which have the advantage that most materials are non-magnetic at these frequencies so the power source dissipates very little energy into extraneous objects (or people). (In contrast, Tesla coils produce strong electric fields external to the device, which interact much more strongly with matter; it's no coincidence that Tesla coils are used as lightning generators.) This operates efficiently at mid-range distances although not as far as radiative transfer (meters at most), does not transfer or dissipate power when the receiver is absent, and is not directional so does not require active "pointing" of the power at the receiver. But it is more complicated than the short-range non-resonant inductive transfer, and requires careful impedance-matching of the source and receiver.

Full disclosure: I know Prof. Soljacic at MIT, who founded WiTricity, although I personally have no financial interest in the company; all of the above information is public and published, however.