Video: Urine-powered mobile phone charger lets you spend a penny to make a call

A group of researchers from the University of the West of England have invented a method of charging mobile phones using urine. Key to the breakthrough is the creation of a new microbial fuel cell (MFC) that turns organic matter – in the case, urine – into electricity. The MFCs are full of specially-grown bacteria that break down the chemicals in urine as part of their normal metabolic process. The bacteria produce electrons as they consume the matter and it this natural process that creates a small electrical charge to be stored in the MFC. "No one has harnessed power from urine to do this so it's an exciting discovery," said Dr Ioannis Ieropoulos, an engineer at the Bristol Robotics Laboratory where the fuel cells were developed.