How do you make a renewable, natural, oxygen-producing, CO2-storing material even more sustainable? Make it as close to zero-waste as possible. Wood waste left over after milling lumber already gets put to myriad valuable uses, from paper products to biomass fuel, and a new innovation will actually enable it to produce clean energy. Engineers at the University of Wisconsin-Madison have discovered a way to manufacture wood floors embedded with wood pulp nanofibers that generate electricity when you step on them.
Chemically treated, tiny cellulose fibers within the waste pulp produce an electrical charge when they come in contact with untreated nano fibers. Stepping on wood floors enhanced with these fibers generates electricity, effectively harnessing energy from footsteps without the need for complex equipment.
Published in the journal Nano Energy on September 24th, 2016, the method is ingeniously simple and inexpensive, with the potential to produce electricity that can be harnessed to power lights or charge batteries. The technology can easily be incorporated into virtually every kind of wood flooring that’s already on the market, including Eastern White Pine.
The functional section of the wood containing the electricity-producing fibers takes up less than a millimeter in thickness, so it doesn’t significantly alter the shape or look of the wood. To produce more energy, manufacturers could simply add more layers.
The technology is currently being tested and optimized on the University of Wisconsin-Madison campus, with a prototype in development to demonstrate the concept.
“Our initial test in our lab shows that it works for millions of cycles without any problem,” says Xudong Wang, an associate professor of materials science and engineering who’s working on the project. “We haven’t converted those numbers into year of life for a floor yet, but I think with appropriate design it can definitely outlast the floor itself.”
Have you ever thought about all of the scraps of wood that are produced as a byproduct of the lumber industry? Once harvested wood is cut and milled, there’s a lot of bark, sawdust and other forms of wood left behind. In the past, much of that wood was simply wasted, but today – with the rise of biomass as a form of renewable energy – it’s helping to power our world in a way that’s far better for the environment and our health than the burning of fossil fuels.
Sustainable biomass is a critical component of a clean energy future. There’s a wide range of biomass resources, ranging from wood waste sourced from the logging and paper industries to crops like switchgrass and even chicken litter. In addition to industry waste wood, which still makes up the majority of biomass burned for power in the United States, energy can be produced from the combustion of forest wood and woody residue.
According to the U.S. Forest Service, thinning out small-diameter and dead trees from overcrowded forests and harvesting the byproducts of forest management (limbs, needles, leaves, etc.) not only improves the health of the trees left behind in the forest, it’s also a valuable opportunity to reduce our dependence on fossil fuels and our greenhouse gas emissions.
Biomass is considered renewable because the carbon stored within trees and released back into the atmosphere remains the same, whether the trees are burned or left to decompose in the natural cycle. If new trees are planted as quickly as the harvested ones are burned, the carbon cycle is balanced. The key to keeping this process sustainable is planting trees for biomass on otherwise unproductive land, or only using byproducts of forest management, rather than cutting down forests specifically for biomass.
Biomass is converted to power in a variety of ways, including direct combustion, in which it is burned to create steam and turn turbines, and co-firing, a process in which it is mixed with coal. Learn more about the technicalities of how biomass works at the Union of Concerned Scientists.
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