by ALex Hutchinson
Vibrations
Whether in bridges, shoes or keyboards, large movements beget smaller ones—most of which go to waste.
PIEZOELECTRICS
+ 3 MICROWATTS PER DEVICE
In November 2010, Georgia Tech researchers built the first nanogenerator capable of powering portable electronics. A simple squeeze of the fingers generated 3 microwatts, enough to light up a liquid crystal display. The generator contains zinc-oxide nanowires, which are piezoelectric, meaning that they create electricity when stressed or deformed. The first proposed application of the new nanogenerator is harvesting vibrations from passing vehicles to provide power for sensors that monitor bridges. Other researchers have been pursuing similar goals. Princeton University scientists have developed “piezo-rubber” that they hope will power implantable pacemakers, eliminating the need to replace batteries. Engineers at Louisiana Tech University have even built a piezoelectric generator into the heel of a shoe. The amount of power harvested by these vibration generators is small—but if they become cheap enough, they could be deployed, well, everywhere.
Popular Mechanics for more