Recharging your laptop computer, your cell phone and a variety of other gadgets may one day be as convenient as surfing the web -- wirelessly.

Scientists discovered electromagnetic radiation in the form of radio waves, and they showed that another form of it--light--is how we get energy from the sun. But transferring energy from one point to another through ordinary electromagnetic radiation is typically very inefficient: The waves tend to spread in all directions, so most of the energy is lost to the environment.

Soljacic realized that the close-range induction taking place inside a transformer--or something similar to it--could potentially transfer energy over longer distances, say, from one end of a room to the other. Instead of irradiating the environment with electromagnetic waves, a power transmitter would fill the space around it with a "non-radiative" electromagnetic field. Energy would only be picked up by gadgets specially designed to "resonate" with the field. Most of the energy not picked up by a receiver would be reabsorbed by the emitter.

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DA Morgan