I. A. Ieropoulos et al., Phys. Chem. Chem. Phys. (2013)

ScienceShot: Urine-Powered Cell Phones Make a Splash

The newest source of battery power for your cell phone is both cheap and abundant. Scientists at the University of the West of England in Bristol report that microbial fuel cells using human urine can directly power a cell phone battery. The researchers first demonstrated in 2011 that our pee is viable fuel: As it cascades through a series of fuel cells, hungry bacteria consume it and release electrons, which generate an electrical current. Their new research, published this week in the Royal Society of Chemistry journal Physical Chemistry Chemical Physics, presents two devices for converting human waste into talk time, which they hope will help people in remote areas stay connected. However, the devices are not quite portable enough to come in handy during a marathon pub crawl. One consists of six, 4-inch-long ceramic cylinders; the other is a network of 25 smaller fuel cells borrowed from the team's waste-fueled EcoBot. And urine-powered conversations would have to be short and sweet. After 24 hours of charging, a Samsung phone stayed alive for 25 minutes—enough to send several texts and make a 6-minute, 20-second call.