Nineteenth-century physicist and engineer Nikola Tesla experimented with long-range wireless energy transfer, but his most ambitious attempt – the 29m high aerial known as Wardenclyffe Tower, in New York – failed when he ran out of money.
Others have worked on highly directional mechanisms of energy transfer such as lasers. But these required an uninterrupted line of sight, and therefore not good for powering objects around the home.
A UK company called Splashpower has designed wireless recharging pads onto which gadget lovers can directly place their phones and MP3 players to recharge them. But the pad is in direct contact with the device.
The concept exploits century-old physics and could work over distances of many metres, the researchers said.
Marin Soljacic, an assistant professor in MIT’s Department of Physics and Research Laboratory of Electronics, described his and his MIT colleagues’ research into the physics of non-radiative energy transfer and the possible design of wireless-power systems yesterday in San Francisco.
Although the team has not built and tested a system, computer models and mathematics suggest it will work. A simple copper antenna designed to have long-lived resonance could transfer energy to a laptop with its own antenna resonating at the same frequency. Energy would only be picked up by gadgets specially designed to “resonate” with the field. The computer would be truly wireless.