Radiated power--and somebody's nuts

The BBC reported on using radiated power to power portable devices. The astute observer will notice that the light bulb in question is connected to a rather large coil--not entirely portable. There's a fancy name for the technology: WiTricity, but one of the people (Prof Pendry) they have explaining it is quoted as saying

"Ordinarily if you have a transmitter operating like a mobile phone at 2GHz - a much shorter wavelength - then it radiates a mixture of magnetic and electric fields," he said.

This is a characteristic of what is known as the "far field", the field seen more than one wavelength from the device. At a distance of less than one wavelength the field is almost entirely magnetic.

"The body really responds strongly to electric fields, which is why you can cook a chicken in a microwave," said Sir John.

"But it doesn't respond to magnetic fields. As far as we know the body has almost zero response to magnetic fields in terms of the amount of power it absorbs."

As a result, the system should not present any significant health risk to humans, said Professor Soljacic.

Somebody doesn't know what he's talking about. I suspect the reporter. Changing magnetic fields produce electric fields. You're not going to get current to flow in the laptop without electric fields. You can get power to transfer more efficiently at resonance, but there still have to be some kind of electric fields.

The fields are probably harmless in any event, since the E/M fields can be small, but the explanation is wrong.