Piezo fabric powers up

Researchers at Chalmers University of Technology have developed a fabric that converts kinetic energy into electric power. According to the team, which is working with the Swedish School of Textiles and Swerea IVF, the greater the load applied to the textile and the wetter it becomes, the more electricity it generates.

The fabric, developed by Chalmers researchers Anja Lund and Christian Müller, features a piezoelectric yarn made of 24 fibres woven together with an electrically conducting yarn. It currently generates enough power to light an LED, send wireless signals or drive small devices, such as a digital watch. Lund and Muller say the fabric is suitable for mass production on industrial looms.

“The textile is flexible and soft and becomes even more efficient when moist or wet,” Lund said. “To demonstrate our research, we used a piece of the textile in the shoulder strap of a bag. When our bag was loaded with 3kg of books, we produced a continuous output of 4µW; enough to intermittently light an LED. By making an entire bag from our textile, we could get enough energy to transmit wireless signals.”