Eric Giler, chief executive of US firm Witricity, talks about a new system that can deliver power to devices without the need for wires. The new system exploits simple physics principles and can be used to charge a range of electronic devices over several meters.
At the TED Global conference in Oxford, Eric Giler showed mobile phones and televisions charging wirelessly. He said the system could replace the billions of disposable batteries and miles of expensive power cables. “There is something like 40 billion disposable batteries built every year for power that, generally speaking, is used within a few inches or feet of where there is very inexpensive power,” he said.
Eric showed off an Apple iPhone and a Google G1 phone that could be charged using the system.
How does this new technique work?
– Magnetic coil (Antenna A) is housed in a box and can be set in wall or ceiling
– Antenna A, powered by mains, resonates at a specific frequency
– Electromagnetic waves transmitted through the air
– Second magnetic coil (Antenna B) fitted in laptop/TV etc resonates at same frequency as first coil and absorbs energy
– Energy charges the device
The new system uses two coils: one embedded or attached to the gadget and the other plugged into the mains. Each coil has the same resonant frequency. When the main coil is connected to an electricity supply, the magnetic field it produces is resonant with that of with the second coil, allowing “tails” of energy to flow between them. As each “cycle” of energy arrives at the second coil, a voltage begins to build up that can be used to charge the gadget.
Eric Giler said the main coil could be embedded in the “floor, in the ceiling or underneath your desktop”. He also added that any gadgets or devices that uses this system would automatically begin to charge as soon as they were within range. “You’d never have to worry about plugging these things in again.”
This kind of wireless power transmission is said to have already been invented by Tesla, in the early 1900s. Reinventing the wheel is, from this perspective, a positive thing, but not already applying what had been invented before our days may have a more political meaning. Watch the video below: