Wednesday, December 03, 2008

Powering the World Using Natural Motion

In the search for alternative energy sources, scientists are moving to harness the natural motion of air and water everywhere.

Take the promising field of piezoelectrics for example. When piezoelectric materials are jostled by something even as mild as a sound wave, they produce a small amount of electrical current. Experts think that with more development, they can use this energy to power hand held electronics without needing batteries.

Research into this phenomenon has been charging full speed ahead. Scientists at the University of Houston recently found that the electrical sweet spot producing the most efficient charge occurs when a piezoelectric filament is about 21 nanometers long. To put that into perspective, if you lined up 4,000 of these filaments next to each other, it would be about the width of a human hair.

The amount of power each filament produces isn't much, but since they're so small, a lot can be wired together inside a cell phone or laptop, no problem. Putting a series of them next to a phone's mouthpiece could power it by converting sound waves into electricity.

Self-powered phones may be years away, but technicians are working on harnessing a different kind of natural motion on a much grander scale.

The ocean is constantly flowing and churning, the perfect source for capturing large amounts of energy. Portugal already has a small power station that converts surface waves into electricity. A brand new design just released by and engineer at the University of Michigan, has long buoys swaying to and fro on the seabed, capturing the force of subtle underwater currents.

Neither of these watery power plants need anything more exotic than old fashioned electromagnetism to work. Much like a traditional power turbine, the swaying buoys induce electricity by moving a large magnet within a coil of wire.

Because water is constantly flowing all over the world, this kind of power source would be abundant and completely renewable


  1. It's really amazing where you can find new sources of energy if you look hard enough. Geothermal heat from the Earth's red hot core is another promising potential energy source.