British scientists have created a new way to charge smartphones - using urine.
Researchers have revealed a new system which transforms urine into electricity using a microbial fuel cell.
Just over half a litre of urine is enough for six hours of charge time, which can power a smartphone for three hours.
The average toilet break produces around 600ml of urine.
Researchers at the University of the West of England hope the technology will eventually allow people to stay connected when off-grid.
Professor Ioannis Ieropoulos, Director of the Bristol Bioenergy Centre, said: 'This project is all about generating1 electricity from waste material.
'In other words, turning waste into something really, really useful.
'-And the microbial fuel cell technology is something that does exactly that.
It takes the waste that we naturally produce and it converts2 it directly into electricity.'
The fuel cells contain living microorganisms such as those found in soil or the human gut3.
In breaking down and processing the urine they produce electrons which can then be harnessed into electricity.