Researchers at the Massachusetts Institute of Technology have successfully tested a system to deliver power to electronic devices wirelessly.
The researchers have successfully sent a beam of electricity, like a radio wave, between two points to power a 60 watt light bulb. The bulb was lit from a power source seven feet away, with no physical connection between the two points.
The project has been dubbed WiTricity, which stands for wireless electricity. The team consisted of both professors and graduates, and it was funded by the US Army Research Office, the US National Science Foundation and the US Department of Energy.
In spite of the fact the power transfer has a limited range, the researchers said: “Power levels more than sufficient to run a laptop can be transferred ... nearly omni-directionally and efficiently.” This applied even when objects obstructed the line of sight between the two coils.
A WiTricity laptop would charge automatically in a room with a transmitter, without having to be plugged in.
The technique is similar to magnetic induction, used in power transformers that have coils very close to each other to transmit power between them. But as the distance increases, these coils become less efficient, according to the researchers.
Reports of the experiment have triggered a storm of blogs from those who argue that electrical scientist Nikolai Tesla created a more powerful power transmitter over a century ago, in his famously dramatic experiments in Colorado Springs.
Among other things, Tesla was the inventor of the Tesla coil, a transformer that uses a technique called the spark gap to transform a low-voltage, low-frequency current into a high-voltage, high-frequency current.