Raise your hand if despite the “wireless” world we live in, your house is littered with cables. C’mon, I know I’m not the only one, fess up. Miriam’s and my apartment has cables everywhere, whether they run to the fan or the speakers, or they form a terrifying mass near the lone desktop. I’ve often wished for wireless electricity, but you know, I was always convinced it would create massive fields of invisible electrical death.
An MIT professor, Marin Soljačić, has devised a way to make wireless electricity, only without the death. He uses the principle of magnetic resonance.
A classic example is a set of wine glasses, each filled to a different level so that it vibrates at a different sound frequency. If a singer hits a pitch that matches the frequency of one glass, the glass might absorb so much acoustic energy that it will shatter; the other glasses remain unaffected.
He uses the same principle for electricity.
He took two copper coils and hung them about six feet apart. He plugged one coil into a wall outlet. then he attached a 60W lightbulb to the second coil. Since the two coils were “tuned” the same (I’m not certain how one tunes a coil) the light bulb lit up.
The application here would be to walk into your house and have your electronics charge automatically – iPod, cell phone, laptop whatever. No more low-battery beeps. No more losing a call to low battery power! No more tripping over the extension cord to the fan, pulling down the fan onto a startled cat causing it to yowl at 2 a.m.! Or is that last one just me?
UPDATE: I’m adding this because Sam asks such an excellent question in the comments below. I’m thinking it will be bad for your electric bill. It’s not clear form my googling whether the transmission coil will be on all the time or not, though I expect you can fix that by turning it on when you come home or something. But the article does mention a 70% efficiency rate, which means you’re losing 30% of your electricity via the transmission over the air. So electric bills will certainly be higher for wireless luxury (though not 30% higher unless you power everything in your house wirelessly).