Wood floors are beautiful, but what if they could generate renewable energy too? Engineers at the University of Wisconsin-Madison have designed revolutionary wood floors that harvest energy from footsteps. Not only can they create power, but the floors are also sustainable because they utilize wood pulp that would most likely be wasted otherwise. Multiple industries end up with wood pulp as a waste product, but inside wood pulp are cellulose nanofibers that have the potential to produce a charge if they are chemically treated and encounter untreated nanofibers.