Economist magazine poses the obvious question that why wireless electric power has not made enough progress? If phone calls and web pages can be beamed through the air to portable devices, then why not electrical power, too?
Gartner, a market-research firm, says the prospects for wireless power are realistic, but the path to widespread adoption may take 3 to 5 years. In December 2008, there was the formation of Wireless Power Consortium, a body dedicated to establishing a common standard for inductive wireless charging, and thus promoting its adoption. Universal standards are the single most important requirement for the adoption of wireless charging, according to the chair of this consortium.
Fierce competition between manufacturers of mobile devices is also accelerating the introduction of wireless charging. The star of this year’s Consumer Electronics Show, an annual jamboree held in Las Vegas, was the Pre, a snazzy smart-phone from Palm. As well as the standard arsenal of technical features—touch-screen, Wi-Fi, GPS, Bluetooth and built-in camera—the Pre also has an optional charging pad, called the Touchstone, which uses electromagnetic induction to charge the device wirelessly. When the device is placed on the pad, the two recognise each other through built-in sensors. Magnets embedded in the pad align the handset and hold it in place during charging.
Fulton Innovations is also a competitor in this and was also present in Vegas with their wireless charging products for cars.
In November 2008 TI announced that it had joined forces with Fulton Innovations “to accelerate development of efficient wireless power solutions”. TI, which provides components to many of the world’s leading mobile-phone makers said it was exploring the production of integrated circuits that supported the technology developed by Fulton Innovations, with the aim of reducing the cost and size of the components needed for wireless charging and making it easier for device-makers to incorporate them into their products quickly.
The magazine article talks about other startups such as WildCharge which has already started selling a number of wireless-charging devices that take a cheaper but simpler approach in which mobile devices make electrical contact with a special charging pad via four small conductive metal studs. WildCharge and the licensees of its technology have developed replacement back covers for a number of popular devices, including Motorola’s RAZR phones and video-game controllers for the Nintendo Wii and the Sony PlayStation 3.
Some companies have taken an approach on the other end of the spectrum: long-range transmission of wireless power.
This technique uses the energy in radio waves, broadcast from a transmitter and harnessed by an antenna, to generate electricity. Using the passive-power principle found in crystal radios, the method has proved successful over short distances in places where it is difficult to replace batteries or carry out maintenance. The problem is that the intensity of the radio waves needed to charge mobile phones and laptop computers over long distances might be hazardous to human health, and regulators would be unlikely to approve.