Urine: The Next Renewable Energy Source

By Christina Phillis

Researchers have long been trying to come up with alternative, more sustainable energy sources. They’ve tried everything from electricity to vegetable oil, but one of the newest choices might be one of the strangest. Using a mini fuel cell, researchers at the University of Bath were able to generate electricity from urine.

The microbial fuel cell that was used to power this innovation is a device that relies on the natural biological processes of “electric” bacteria to turn organic matter into electricity. For the reaction to happen, urine must pass through the fuel cell. Then electricity generated by bacteria can be either stored or used directly to power electrical devices.

A Smaller Fuel Cell

In addition to developing a new source of energy, researchers set out to make a fuel cell that is smaller, more powerful and cheaper than other devices. The fuel cell they developed, with the help of Queen Mary University of London and the Bristol Bioenergy Centre, is one inch square in size. They used ovalbumin, a protein found in egg white, and glucose as catalysts. This combination is much cheaper than the platinum used in other fuel cells and, more importantly, renewable.

To maximize the amount of power this tiny fuel cell could generate, scientists enlarged the cell’s electrodes from 4mm to 8mm, which increased the power tenfold. Additionally, they stacked multiple units together, increasing the power further.

The fuel cell can generate 2 Watts per cubic meter of power, or just about enough energy to power a cell phone. Although this doesn’t seem like much compared to other renewable sources, the technology is worthwhile because of its cost, inexhaustible supply and lack of harmful gases.

The team of researchers is currently working on improving the power output of the cell. By optimizing the design of the cell, they are optimistic that they can improve its performance. In the future, this device has the potential to generate electricity in remote areas for only about $1.50 to $3. “To have created technology that can potentially transform the lives of poor people who don’t have access to, or cannot afford electricity, is an exciting prospect,” Jon Chouler, lead researcher, told Science Daily.