Researchers at University of Wisconsin-Madison have developed an inexpensive, simple method that allows them to convert footsteps into usable electricity.
The method puts to good use a common waste material -- wood pulp. The pulp, which is already a common component of flooring, is partly made of cellulose nanofibers.
They are tiny fibers that, when chemically treated, produce an electrical charge when they come in contact with untreated nanofibers.
When the nanofibers are embedded within flooring, they are able to produce electricity that can be harnessed to power lights or charge batteries.
And because wood pulp is a cheap, abundant and renewable waste product of several industries, flooring that incorporates the new technology could be as affordable as conventional materials.
While there are existing similar materials for harnessing footstep energy, they are costly, nonrecyclable, and impractical at a large scale.
"We've been working a lot on harvesting energy from human activities. One way is to build something to put on people, and another way is to build something that has constant access to people. The ground is the most-used place," said Xudong Wang, Associate Professor at University of Wisconsin-Madison.
The team's method published in the journal Nano Energy is the latest in a green energy research field called "roadside energy harvesting" that could, in some settings, rival solar power -- and it does not depend on fair weather.
Researchers like Wang who study roadside energy harvesting methods see the ground as holding great renewable energy potential well beyond its limited fossil fuel reserves.