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Did you ever hear of it? Wireless electricity. How can it be possible to transfer power without cable? It’s not a new idea. Scientists are researching on it for about 100 years. But it’s only few years that it has come to reality. Though, it’s in initial experimental state, I am sure it has a bright future, if the scientists are successful. Just think, the electricity is movie like your data on the air. Unbelievable! So far only one device could be powered through wireless electricity. Recently, MIT WiTricity team powers two devices simultaneously. They come to the point that using magnetic induction to send electricity to devices is more efficient when more than one machine is involved. The efficiency of the energy is better for multiple machines.

Before, high-powered microwaves to focused beams of infrared had being tested. But researchers at the Massachusetts Institute of Technology (MIT), led by physicist Marin Soljacic, think using magnetic fields to induce a current in a distant device is the most promising approach. They tune the transmitter and receiver to magnetically resonate at the same frequency to maximise efficiency. Waves carry energy most effectively between objects that resonate at the same frequency, an effect at work when a singer smashes a nearby glass with the right note.

Previously, an MIT WiTricity team powered a 60-watt light bulb from across the room using a magnetic coil. That was 2007.

Yesterday, that MIT team has shown it is possible to power two devices, wirelessly, when the are placed on either side of a single 1-sq. meter coil. The effective distance from coil to device was anywhere between 1.6 to 2.7 meters. Cooler still, the researchers discovered that by using two devices the power transfer was 10% more effective than using just one. Additionally, the researchers’ models suggest that the efficiency would increase even more should they try and introduce more devices into the mix.

According to New Scientist:

That makes it possible to power a collection of devices with poor individual links, perhaps because they are scattered across a room far from the coil. “We could have reasonably good efficiency over a room-sized area from a coil embedded in ceiling or a wall in order to power multiple gadgets or devices,” said Kurs. The efficiency increases because more of the broadcasting coil’s field falls on receptive receivers.

“This is a promising road to full wireless connectivity, not just for signals but also for power,” says electrical engineer Luk Arnaut of Imperial College London. “However, the efficiency of the system rapidly deteriorates with increasing distance,” he adds, explaining that specialised antennae will need to be developed to counter that.

The MIT researchers have set up a spin off company called WiTricity Corporation, joining electronics firms such as Sony in trying to commercialise wireless electricity transfer.

The end game is a wall or ceiling-mounted coil that would wirelessly power an entire room of gadgets. One remaining issue is distance: When the devices are moved outside the 1-2 meter range, the signal deteriorates rapidly, as would be expected. Fortunately for wireless power buffs, MIT is working on a specialized antenna to counter the weakening signal.

Just watch this funny but informative video

Source: New Scientist, Gizmodo