Intel demonstrates wireless electricity
The wall-outlet crawl is a familiar dance that takes place in cafes and airport terminals: laptop computer and cell-phone users desperately hunting for a place to plug in their gadgets, rearranging furniture or settling uncomfortably on the floor to access an outlet.
If only there were a way to pull electricity out of the air, letting consumer electronics operate and recharge while untethered.
Scientists are now hot on the trail, trying to do for electricity what Wi-Fi did for the Internet. The idea is to perfect a transmitter that sends electricity coursing through a room to gadgets, eliminating the need for messy and inconvenient cords.
The technology for wireless power is emerging, and Intel Corp. took a significant stride toward a power cord-less future Thursday when it demonstrated a system that made a light bulb glow when it was several feet from its power source.
Intel's setup was more science fair than Best Buy, but wireless power researchers say the technology points to a future when electricity hot spots coming from a single source in a room provide juice to any number of electronic devices within range.
Picture an airport gate area where every passenger's computer and phone gets charged before boarding, or an office worker not worrying about battery power for a laptop. Researchers say such widespread consumer applications are likely several years away.
"It's an engineering challenge just to build a system that's actually useful," said Joshua Smith, a Seattle-based researcher at Intel. "What we showed was powering a light bulb. But to make it work, we need to power a laptop or a battery charger, which is actually a little bit different. There are still quite a few unknowns."
Intel's work in this field piggybacks on research at the Massachusetts Institute of Technology, which unveiled its breakthrough in June 2007. MIT professor Marin Soljacic got the idea for wireless power one night when he was again roused by his cell phone, which was beeping because it was low on battery power. He wanted to develop a technology to let his phone charge itself.
MIT isn't working with Intel, but Soljacic welcomed the company's news.
"It's very exciting that other people are taking very serious interest and it also demonstrates the potential of wireless power," Soljacic said. "It's something that would undoubtedly have many applications."
Soljacic said the technology could power the wireless recharging of pacemakers, eliminating the need for invasive surgery. Meanwhile, industrial company Leggett & Platt has partnered with Fulton Innovation, a Michigan-based technology firm, to outfit a new line of trucks that charges flashlights and power tools as they sit on a shelf.
Dave Baarman, Fulton Innovation's director of advanced technologies, said he remains skeptical that consumers and regulators will embrace residential electric hot spots, despite researchers' assurances that the technology is safe for humans.
"I don't think the public is ready to say: 'We're going to broadcast kilowatts of power across your living room,'" Baarman said. "We have a big enough issue with some of the really low-power transmitters, like cell phones."
Intel and MIT's systems use electromagnetic fields that are generated when two objects resonate at the same frequency, similar to how a singer can shatter a glass by finding the exact pitch at which the glass is vibrating. Powercast, a company in Philadelphia, is looking at different wireless power technology that converts radio waves to electricity.
Both systems are built to transmit power over a room-size area. Trying to provide enough wireless power for a city block would pose technical and health risks, researchers say.
"We never want to be putting out enough power that we would in any way impact safety," said Steve Day, senior director of marketing at Powercast.
In the early 20th century, inventor Nikola Tesla attempted to build a tower that would wirelessly send power over long distances. His efforts proved unfruitful, and modern initiatives have also presented challenges.
Mohammad Shahidehpour, who chairs the electrical and computer engineering department at the Illinois Institute of Technology, said he worked with NASA a decade ago on technology to beam solar power from space to Earth in the form of a laser.
"The problem was that if you moved it a fraction of a degree, you could melt a city," Shahidehpour said.
For now, despite Tesla and his successors' efforts, there still isn't a wireless replacement that bests the traditional electrical grid.
Tesla "never dreamt that people would have loved electricity so much they would drag this huge infrastructure of metal wires across continents," Soljacic said.