The Power Within
Charge your tech gadgets only with your voice
by: Jerry Liao
What do you do if you need to make an important call to a business partner or to a friend? Or you need to open your notebook computer only to find out you forgot to charge your device.
Panic will be the first reaction, frustration will come in second, and then its either you will look for the nearest mobile phone charging station or will look for a friend who will allow you to insert your SIM into use his/her phone. For notebook users, looking for the nearest internet cafe would be a solution.
Battery life remains a major concern for popular mp3 players and cell phones that are required to perform an ever-expanding array of functions. But beyond mere consumer convenience, self-powering devices are of major interest to several players.
Wouldn’t it be great if we can charge our mobile phones, notebooks and other devices by mere our voice?
Thanks to the recent work of Tahir Cagin, a professor in the Artie McFerrin Department of Chemical Engineering at Texas A&M University, the idea is not as far-fetched.
Utilizing materials known in scientific circles as “piezoelectrics,” Cagin, whose research focuses on nanotechnology, has made a significant discovery in the area of power harvesting – a field that aims to develop self-powered devices that do not require replaceable power supplies, such as batteries.
Specifically, Cagin and his partners from the University of Houston have found that a certain type of piezoelectric material can covert energy at a 100 percent increase when manufactured at a very small size – in this case, around 21 nanometers in thickness.
Key to this technology, Cagin explained, are piezoelectrics. Derived from the Greek word “piezein,” which means “to press,” piezoelectrics are materials (usually crystals or ceramics) that generate voltage when a form of mechanical stress is applied. Conversely, they demonstrate a change in their physical properties when an electric field is applied.
His findings, which are detailed in an article published this fall in “Physical Review B,” the scientific journal of the American Physical Society, could have potentially profound effects for low-powered electronic devices such as cell phones, laptops, personal communicators and a host of other computer-related devices used by everyone from the average consumer to law enforcement officers and even soldiers in the battlefield.
Many of these high-tech devices contain components that are measured in nanometers – a microscopic unit of measurement representing one-billionth of a meter. Atoms and molecules are measured in nanometers, and a human hair is about 100,000 nanometers wide.
“Even the disturbances in the form of sound waves such as pressure waves in gases, liquids and solids may be harvested for powering nano- and micro devices of the future if these materials are processed and manufactured appropriately for this purpose,” Cagin said.
While advances in those applications continue to progress, piezoelectric work at the nanoscale is a relatively new endeavor with different and complex aspects to consider, said Cagin.
On a grander scale, some night clubs in Europe feature dance floors built with piezoelectrics that absorb and convert the energy from footsteps in order to help power lights in the club. And it’s been reported that a Hong Kong gym is using the technology to convert energy from exercisers to help power its lights and music.
“When materials are brought down to the nanoscale dimension, their properties for some performance characteristics dramatically change,” said Cagin who is a past recipient of the prestigious Feynman Prize in Nanotechnology. “One such example is with piezoelectric materials. We have demonstrated that when you go to a particular length scale – between 20 and 23 nanometers – you actually improve the energy-harvesting capacity by 100 percent.
“We’re studying basic laws of nature such as physics and we’re trying to apply that in terms of developing better engineering materials, better performing engineering materials. We’re looking at chemical constitutions and physical compositions. And then we’re looking at how to manipulate these structures so that we can improve the performance of these materials.”
Though Cagin’s subject matter is small, its impact could be huge. His discovery stands to advance an area of study that has grown increasingly popular due to consumer demand for compact portable and wireless devices with extended lifespans.
As they always say, the power is within everyone of us.