Now, human pee to charge cellphones

Pee power! In a world first, UK scientists claim to have developed a novel method to charge mobile phones - using human urine.

Scientists working at the Bristol Robotics Laboratory have described the "breakthrough" finding of charging cell phones using urine as the power source to generate electricity.

"We are very excited as this is a world first, no-one has harnessed power from urine to do this so it's an exciting discovery. Using the ultimate waste product as a source of power to produce electricity is about as eco as it gets," Dr Ioannis Ieropoulos from University of the West of England (UWE), Bristol, an expert at harnessing power from unusual sources using microbial fuel cells, said.

"One product that we can be sure of an unending supply is our own urine. By harnessing this power as urine passes through a cascade of microbial fuel cells (MFCs), we have managed to charge a mobile phone. The beauty of this fuel source is that we are not relying on the erratic nature of the wind or the Sun, we are actually re-using waste to create energy," said Ieropoulos.

He said so far the microbial fuel power stack that scientists have developed generates enough power to enable SMS messaging, web browsing and to make a brief phone call.

"Making a call on a mobile phone takes up the most energy but we will get to the place where we can charge a battery for longer periods. The concept has been tested and it works - it's now for us to develop and refine the process so that we can develop MFCs to fully charge a battery," he said.

The Microbial Fuel Cell (MFC) is an energy converter, which turns organic matter directly into electricity, via the metabolism of live microorganisms, researchers said.

Essentially, the electricity is a by-product of the microbes' natural life cycle, so the more they eat things like urine, the more energy they generate and for longer periods of time; so it's beneficial to keep doing it, they said.