When you go on a trip, how many cords, chargers and batteries do you need to bring with you to power up all your gadgets – your digital camera, gaming device, cell phone, Blackberry, iPod and laptop. When you are at home, how long does it take you to find the right plug from among the tangle of cords coming out of every outlet?
Someday, the solution to your problem could be wireless power transmission. While powering up electrical devices without power cords may sound like science fiction, it isn’t. Over a century ago, Nicola Tesla proposed theories of wireless power transmission (but he was never able to implement them because he ran out of capital). Of course, radio waves or Wi-Fi are a form of wireless transmission of power, but they are not feasible for substantial power transmissions because radio waves and Wi-Fi radiation spread in all directions and vast amounts of power end up being wasted.
Dell Latitude Z
Several wireless charger based products are currently available in the market. Examples are Powermat, WildCharge, Dell Latitude Z and the Touchstone charger for the Palm Pre. These products however still require a physical contact between the charger and the device to power up.
Recently, a new company, WiTricity, based in Watertown, MA has been developing a technology for charging electrical devices without any physical contact. The technology uses oscillating magnetic fields to exchange energy efficiently between twp objects without leaking much power to other objects. MIT physicist, Marin Soljacic, came up with the idea about two years ago when dying batteries of his wife’s cell phone beeped every night as they ran out of power.
The WiTricity system is able to operate safely because when two objects have the same resonant frequency, they exchange energy strongly without having an effect on other, surrounding objects. The system does not involve a transfer of electricity and therefore poses no risk of electrocuting anyone.
WiTricity thinks its system could replace miles of expensive power cords and billions of disposable batteries. Whether it will be successful remains to be seen. Wouldn’t it be great though if we could throw out our power cords and with a simple device half way across the room power up all our electrical devices?
