The wireless power room in action. Moshe Mahler/Disney Research
Mickey Mouse, Donald Duck, and… breakthroughs in wireless power transfer? Yep, scientists at a branch of the Walt Disney Company called Disney Research have found a way to charge devices on a room-scale without using any wires.
Wireless power is an idea that goes back to the 19th century, with Serbian-American inventor Nikola Tesla perhaps being its most famous proponent. But getting it to work has been a bit of a problem, with the extent of modern wireless power coming mostly in the form of electric toothbrushes or flat charging pads for phones.
A team at Disney Research, though, showed how they were able to transmit power in an entire room, powering a variety of devices while remaining relatively safe for humans. They published their findings in the journal PLOS ONE.
“Wireless power delivery has the potential to seamlessly power our electrical devices as easily as data is transmitted through the air,” they wrote in a brief statement. “However, existing solutions are limited to near contact distances and do not provide the geometric freedom to enable automatic and un-aided charging.”
To solve this, the team came up with “quasistatic cavity resonance (QSCR)”, where magnetic fields are generated to deliver kilowatts of power to receivers. These receivers can be connected to a device, like a phone or fan, to supply it with power.
The room built by Disney Research was lined with aluminum panels. In its center was a copper tube between the floor and the ceiling, with a current running through it. Fifteen capacitors in the pole are used to set a resonant frequency in the room and isolate electric fields from a signal generator, which outputs at 1.32 MHz. A uniform magnetic field is then run through the room at the same frequency.
The receivers use a coil of wire to resonate at the same frequency, providing power to a device. The researchers were able to deliver about 1,900 watts with an efficiency of 40 to 95 percent.
There are a couple of issues, though. First is obviously the need for an aluminum-encased room, although they note their design – 54 cubic meters (1,900 cubic feet) – can easily be scaled up or down. Also, the circular nature of the magnetic field produced means receivers only work when at right angles to it, although this can be solved with three coils pointing in different directions.
It's safe for the most part too, although the researchers note people shouldn't stand closer than 46 centimeters (18 inches) to the pole, which exceeds federal guidelines for how much energy a human can be subjected to, known as specific absorption rate (SAR). Oh, and if you're pumping 1,900 watts into the room, you also need devices to be using this to remain safe.
Otherwise, sign us up.
