Air Date: Week of February 27, 2004

Living on Earth’s Cynthia Graber reports that bacteria can clean waste water and generate electricity for a fuel cell - at the same time.

Transcript

CURWOOD: Just ahead: organic winegrowers go after genetically engineered crops at the ballot box. First, this note on emerging science from Cynthia Graber.

[SCIENCE NOTE THEME]

GRABER: Many treatment plants use bacteria to clean wastewater. Now, scientists at Penn State have shown that this waste-eating bacteria can be used to generate electricity in fuel cells, while cleaning the water at the same time. The process works like this: As bacteria consume their food – in this case, the organic matter in wastewater – they shed electrons. These electrons are then captured by a wire in the fuel cell. The wire transfers these electrons to a chamber of oxygen. This flow of electrons creates electricity.

Until now, scientists have used simple sugars, such as glucose, to power the bacteria in these so-called microbial fuel cells. Researchers are hoping to refine the wastewater technology so that larger amounts of electricity are produced. Eventually, they say, providing power on site could help lower the cost of operating wastewater plants. Developing countries could benefit from this technology by reducing costs of cleaning contaminated water, thereby slowing down the spread of disease. That’s this week’s note on emerging science, I’m Cynthia Graber.

CURWOOD: And you’re listening to Living on Earth.

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[MUSIC: Star Wars: Figrin d'An and the Modal Nodes "Cantina Band #2" (RCA - 1997)]