At Massachusetts Institute of Technology (MIT), a team led by assistant professor Marin Soljacic is developing a method to broadcast power to devices to charge them, rather than depending on cords and cables. Instead of irradiating the environment with electromagnetic waves, a power transmitter would fill the space around it with a "non-radiative" electromagnetic field. Only devices designed to "resonate" with the field would pick up energy. Energy not picked up by a receiver would be reabsorbed by the emitter.
Still in the simulation stage, these non-radiative wireless power emitters would have limited range, and the range would be shorter for smaller-size receivers. The team calculates that an object the size of a laptop could be recharged within a few meters of the power source. Placing one source in each room of a house could provide coverage throughout. Wireless energy could find industrial applications powering freely roaming robots within a factory pavilion or charging cell phones.
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