SciTech

Wireless electricity eliminates tangled cords

Wireless electricity is based off the idea of energy conversion; electrical energy can be converted into different forms of energy, like magnetic energy, to send it wirelessly across distances. Wireless electricity may be common within the next few years. (credit: Soojin Yoon/Art Staff) Wireless electricity is based off the idea of energy conversion; electrical energy can be converted into different forms of energy, like magnetic energy, to send it wirelessly across distances. Wireless electricity may be common within the next few years. (credit: Soojin Yoon/Art Staff)

A common fixture in any college dorm room is the overflowing power strip, with wires stretching across the room to power laptops, TVs, microwaves, and mini-fridges. This unavoidable disarray is common enough to be tolerated, but eliminating the need for wires is a thought that has probably crossed the minds of many individuals. With current research in this field, however, this may become a reality in upcoming years.

Wireless electricity is based off a concept known as resonant energy transfer, introduced around 100 years ago by Nikola Tesla. At TEDGlobal 2009, WiTricity CEO Eric Giler explained that a wire coil, called the power source coil, uses electricity to resonate at a very high frequency. The energy from the coil’s resonance can then cause another coil to resonate without having to physically touch the original coil. The second coil is the power capture coil, which is made to resonate only at the same frequency as the power source coil. If the two coils are placed close enough, the power source coil will cause the power capture coil to resonate, and magnetic energy will transfer between them. This is the basis of wireless electricity transfer.

“The power source converts the electricity into an oscillating magnetic field, and the magnetic field carries the energy from point A to point B, and at point B it’s converted from a magnetic field back into electricity,” explained David Schatz, director of business development and marketing at WiTricity.
Scientists at WiTricity state that wireless energy transfer will provide more than just convenience and better organization.

Many electronic devices today are powered by disposable batteries, which are detrimental to the environment, cost-ineffective, and inefficient compared to many other sources of power, according to Giler. In addition, batteries are often used around power sources. “By building an electricity power source into one of these heavy devices [like a computer] that’s around and happens to be plugged in, you can then use it in devices that are always used nearby [like an iPod or cell phone],” Schatz said, “and thus they don’t even need to have a battery.”

WiTricity, a company founded in 2007, is hoping to revolutionize the way electronics may be powered in the future. The name WiTricity comes from “wireless” and “electricity,” which is a perfect description for their research. Currently, the company is developing a method to safely power electronics without using wires. Other companies are working on different forms of wireless electricity, like WiPower, which hopes to be able to charge devices wirelessly using a charging pad.

It may be shocking to think that power cords will someday be a thing of the past, but it has already been proven that this technology is functional.
Just recently, working with electronics manufacturer Haier, WiTricity showcased their product at the 2010 Consumer Electronics Show by powering a 32-inch TV set completely without wires, according to a report from www.SFGate.com.

While this revolutionary technology is enticing, roadblocks do exist in its distribution. “It takes a while to convince companies to adopt something as radically new and different as this, because they have to change their products to incorporate it,” Schatz said. “And we have to take the technology and develop it from some sort of laboratory scientific experiment to something that can be produced in the factory.”

It will take more improvement before wireless electricity devices will be able to be produced efficiently and cost-effectively. In addition, there is a range limitation for powering devices. Schatz realizes that some devices will eventually need to move away from power sources. “What we’ll be able to do with those products is to be able to allow them to charge without having to be plugged in. In some cases you can directly power things if they happen to be always used in proximity to a source, and in other cases you can usually charge the devices when they’re in proximity to the source,” he said. In short, wireless electricity can be used to directly power larger appliances that are not mobile, like desktop computers, and can also be used to charge devices that can be taken anywhere, like cell phones.

Despite the current limitations, we can expect to see this technology being implemented in the very near future. Schatz said that while the technology “is more of a conceptual design, in 2010 the very first of our products will be shipped to customers in commercial and military applications. In the end of 2010 and early 2011, it will start to be shipped in some consumer electronics applications.”