Wireless Electricity Is Here (Seriously)

By: Paul HochmanTue Jan 6, 2009 at 1:30 PM

Photograph by Phillip Toledano

Ryan Tseng, CEO of WiPower, says his system is cheaper and better than rival eCoupled's. | Photograph by Phillip Toledano

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Ryan Tseng holds his wirelessly lit lightbulb 3 inches above its power source. | Photograph by Phillip Toledano

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The dominant player in this technology for the moment seems to be Michigan-based Fulton Innovation, which unveiled its first set of wirelessly charged consumer products at the Consumer Electronics Show early this year. Come April, Fulton's new pad-based eCoupled system will be available to police, fire-and-rescue, and contractor fleets -- an initial market of as many as 700,000 vehicles annually. The system is being integrated into a truck console designed and produced by Leggett & Platt, a $4.3 billion commercial shelving giant; it allows users to charge anything from a compatible rechargeable flashlight to a PDA. The tools and other devices now in the pipeline at companies such as Bosch, Energizer, and others will look just like their conventional ancestors. Companies such as Philips Electronics, Olympus, and Logitech will create a standard for products, from flashlights to drills to cell phones to TV remotes, by the end of this year.

TECH 2: Radio-frequency Harvesting
Availability: April

>> THE INDUCTION SYSTEMS are only the beginning. Some of the most visually arresting examples of wireless electricity are based on what's known as radio frequency, or RF. While less efficient, they work across distances of up to 85 feet. In these systems, electricity is transformed into radio waves, which are transmitted across a room, then received by so-called power harvesters and translated back into low-voltage direct current. Imagine smoke detectors or clocks that never need their batteries replaced. Sound trivial? Consider: Last November, to save on labor costs, General Motors canceled the regularly scheduled battery replacement in the 562 wall clocks at its Milford Proving Ground headquarters. This technology is already being used by the Department of Defense. This year, it will be available to consumers in the form of a few small appliances and wireless sensors; down the road, it will appear in wireless boxes into which you can toss any and all of your electronics for recharging.

TECH 3: Magnetically Coupled Resonance
Availability: 12-18 months

>> INVENTED BY MIT'S SOLJACIC (who has dubbed it WiTricity), the technique can power an entire room, assuming the room is filled with enabled devices. Though WiTricity uses two coils -- one powered, one not, just like eCoupled's system -- it differs radically in the following way: Soljacic's coils don't have to be close to each other to transfer energy. Instead, they depend on so-called magnetic resonance. Like acoustical resonance, which allows an opera singer to break a glass across the room by vibrating it with the correct frequency of her voice's sound waves, magnetic resonance can launch an energetic response in something far away. In this case, the response is the flow of electricity out of the receiving coil and into the device to which it's connected. The only caveat is that receiving coil must be properly "tuned" to match the powered coil, in the way that plucking a D string on any tuned piano will set all the D strings to vibrating, but leave all other notes still and silent. (This explains why Soljacic considers the machinery that create these frequencies, and the shape of the coils, top secret.)

Importantly, then, WiTricity doesn't depend on line-of-sight. A powered coil in your basement could power the rest of the house, wirelessly. Will the cat be okay? "Biological organisms are invisible to, and unaffected by, a magnetic field," Soljacic says. While I am mulling that statement, he tells me the company will not yet reveal the name of its partners because those partnerships haven't been formalized, but they include major consumer electronics brands and some U.S. defense customers.

As has been the tradition since Nikola Tesla and Thomas Edison angrily parted ways in 1885, the enormous consumer demand for wireless electricity is begetting intense competition. Last November, a consortium of manufacturers coalesced around Fulton's eCoupled system. But Fulton and WiTricity aren't the only companies fighting to bring wireless electricity to market. WiPower, in Altamonte Springs, Florida, has also created an induction system and says it, too, is close to announcing partnerships. And Pittsburgh-based Powercast, an RF system, sells wireless Christmas ornaments and is testing industrial sensors for release this summer.