Pulling Power Out Of Thin Air

By Cheryl Ajluni

It wasn’t all that long ago that voice communication via a traditional landline was the norm. At the time, consumers would have been hard pressed to imagine a world in which anytime, anywhere communication (voice and data) with a device no bigger than the human hand was possible.

Many of those same consumers might today find it hard to conceive of a world in which their mobile phones are powered by the jacket they are wearing, but that too—like the mobile phone—may one day become a commercial reality. Given the ongoing research and developments in this area, that reality may be closer than many people think.

One technology hoping to give life to this vision is energy harvesting—a process by which energy is derived from an external ambient source (e.g., kinetic energy, RF, solar power, thermal energy, or vibration and wind energy), captured and then stored. Energy harvesting devices convert the ambient energy into electrical energy. In a wearable electronics application, for example, power captured from an ambient energy source is converted to electrical energy and stored in a device like a battery or a capacitor. The stored power can then travel through a microprocessor and be subsequently transmitted, usually wirelessly. Energy harvesters generally provide only small amounts of power (e.g., just a few milliwatts), dependent in part on their design and size, and are therefore considered suitable for powering low-energy electronics or small, autonomous devices like those used in wearable electronics and wireless sensor networks.

To read the complete article, please visit: http://www.chipdesignmag. com/lpd/blog/2009/09/17/pulling-power-out-of-thin-air/