Imagine a device that fits inside a pair of shoes, harvests the energy leftover from walking and stores it in AAA or watch batteries. At the Center for Research in Advanced Materials (CIMAV) in Chihuahua, Mexico, scientists have done just that. 


CIMAV personnel have designed 
a cylinder to store the mechanical-
vibrational energy a person generates when walking. With the captured energy, they have been able to recharge AAA and watch batteries.


The prototype is a pill-shaped device with a diameter of 2 inches and a thickness of ⅛ inch that fits in a shoe sole.


Abel Macias Hurtado, head of research and specialist in materials science, said the pill is a piezoelectric device, measuring pressure, force and acceleration, that is placed in the sole of a shoe and converts mechanical energy into microwatts using a circuit. 


When connected to batteries, it was tested with good results. Hurtado indicated that, in the area of nanostructured materials, an important base of the research is to harvest or produce clean energy, and this prototype is ideal for that purpose.


“We want to improve the circuit of the tablet to make it more efficient at capturing energy,” he said. “Now we are working in making it more efficient; currently, we already have clean energy.”


Hurtado said that, although a pair of shoes can generate power for the operation of a battery, he is considering adapting a similar system on a “mat” and placing it on the entry of a mass transport system. There it could generate energy capable of illuminating the public transport stations.


“Today, the energy generated by people walking is wasted; if we learn to harvest it and turn it into electricity, we can contribute to the global impact,” Hurtado said.