Say goodbye to range anxiety with the electric car you don't have yet if Stanford makes this project a reality: by embedding resonating magnetic coils under roads, you'd be able to charge your car while you drive and get to your destination with more juice in your batteries than when you left.
Magnetic resonance coupling is a way of transmitting power wirelessly using two coils of metal wire that have been tuned to resonate at the same natural frequency. Think of it like a speaker placed next to a wine glass: if you hit the right pitch with the speaker, the wine glass will begin to resonate with it, wirelessly converting energy from the speaker into mechanical motion. You can do the same sort of thing with coils of wire, except using magnetic fields to transmit electricity instead of using sound to transmit mechanical energy.
What a research team at Stanford wants to do is to embed these resonating coils into roadways, with other coils in the bottom of your car, so that whenever you were driving you'd also be constantly receiving a charge. The resonating system will function at distances of up to six feet, and the peak efficiency is about 97%, which is pretty damn good. Oh, and the reason that your car won't explode (and why you'd be able to walk on an actively resonating road and not get fried) is that unless something is resonating at the exact same frequency as a coil, it's entirely unaffected. You can even walk between two coils that are transmitting power safely.
This idea looks fantastic on paper: if all highways have continuous charging systems, you'd never have range anxiety. You could drive anywhere without stopping for gas. Power generation could be distributed in eco-friendly ways. Also, since highways would have these coils running down the center of each lane, GPS accuracy could be improved to tell your car which lane it's in, opening up opportunities for increased safety and autonomous operation.
You've probably spotted the big stumbling block to this project: to implement it will involve "revamping the entire highway system," Stanford acknowledges. And it'll also involve revamping the electric car manufacturing system, too. It might make the most sense to try and install this stuff gradually, over heavy use areas, since those areas generally need relatively frequent revamping anyway, and then if it ends up being as brilliant as it purports to be, we can suck it up and wire up the rest of our roads from there.
Via Stanford News