Robots could be powered by pee

Posted by Emma Woollacott

A team at the Bristol Robotics Lab is looking into the use of urine as the fuel for Microbial Fuel Cells (MFCs), which use bacterial cultures to break down 'food' to create power.

The team has previously developed EcoBot-III, a robot which can power itself by digesting waste. In the past, Dr Ioannis Ieropolis has fed his MFCs with everything from rotten fruit to dead flies. Now, he plans to add to that appetizing menu by using urine as a potential power source.

He also wants to scale up the MFCs so that they can work together in a 'stack' – a series of cells which are connected both electrically and in terms of the liquid feed-lines under a continuous flow system.

"Urine is chemically very active, rich in nitrogen and has compounds such as urea, chloride, potassium and bilirubin, which make it very good for the microbial fuel cells. We have already done preliminary tests which show it being a waste material that is very effective," says Dr Ieropoulos.

"Although it is early days for this research, we hope to work towards producing a prototype portable urinal which would use urine to create power from fuel cells.  We envisage that this could be used, for example, at music festivals and other outdoor events."

The researchers are already talking to a waterless urinal company, Ecoprod Technique, about the technology. 

"We are looking forward to helping with this unique project with the supply of Urimat – The Waterless Urinal which the research team have chosen," says Ecoprod's Marcus Rose.

"This will be a valuable and interesting collaboration for the company to be involved in."