Microbial Fuel Cell

The research team at the Bristol Robotics Laboratory which is part of the University of the West of England created a microbial fuel cell (MFC) that is being powered by urine. The MFC is an energy converter which turns organic matter directly into electricity via the metabolism of live micro-organism. The researchers managed to design the microbial fuel cell by growing bacteria on carbon fi ber anodes and then placing them in ceramic cylinders. When urine is placed in the cell, the bacteria breaks down the chemicals in the urine, creating an electrical charge which is stored on a capacitor. By harnessing the power as urine passes through a cascade of MFCs, the researchers managed to charge a Samsung mobile phone. The researchers used 12 ceramic cylinders 10.2 cm (4”) long wired with a cathode and an anode. These cylinders were stacked in sets of three with each stack acting as a cascade – thus allowing continual charging while the urine passes through each cascade. Currently the technology is the size of a car battery containing a stack of the microbial fuel cells and can power a cell phone enough to send texts, browse the web or for a short phone call. The team ultimately hopes that the technology could lead to a smart toilet that can produce electricity from urine. This new technology might also be interesting for a decentralized concept of energy harvesting, since we have access to an almost unlimited supply of urine. One possible applucation might be the installation of the microbial fuel cell in bathrooms to harness the urine and produce suffi cient electricity to power showers, lighting or razors as well as mobile phones. Furthermore, it would allow cities to use their liquid waste in a sustainable way that even allows them to generate energy.