A car tire is a car tire, right? Well, not according to scientists at the University of Wisconsin-Madison. They developed an energy generating car tire that harvests energy from friction. The scientists concluded that the friction created as a car’s tires run over the ground accounts for approximately 10% of the vehicle’s fuel usage. A waste of energy, they thought, so they started looking into ways to embed the tire with a nanogenerator and electrodes. These produce a small electric current when they rub against the road. The technology still needs more research and improvement but has the potential to make cars more energy-efficient.