This is the hope of a research team at the University of Queensland, who was just awarded funding in the amount of $140,000 by the Queensland Government’s Sustainable Energy Innovation Fund. The researchers will attempt to transform organic matter leftovers of brewery wastewater into a source of energy, using microbial-based fuel cells, or biocells, to drive the process. A biocell prototype has already been produced, and plans are underway to create a bigger, more workable, model.

Korneel Rabaey, one of the researchers, states that biocells work like batteries, in that they generate electricity via an electron-yielding chemical reaction. However, unlike conventional batteries, which run down unless recharged, biocells are continually recharged by the influx of food metabolites, allowing a constant release of electrons and thus electricity. Clean water and renewable (non-polluting) carbon dioxide are also produced. Therefore, not only could microbial fuel cells be used to generate energy, but also to treat sewage water.

The University of Queensland group is not the only batch of researchers attempting to make a working biocell. At Pennsylvania State University, Bruce Logan and his colleagues are testing out another biocell prototype. The Plexiglass cylinder contains rows of anodes (negative electrodes), upon which the bacteria are attached, and a single central cathode (positive electrode). Generated electrons travel from anode to cathode, moving along a wired circuit.

The wastewater that is pumped through the fuel cell nourishes the bacteria, whereupon they digest organic matter and release electrons into the cell’s circuitry. The bacteria also release hydrogen ions, which pass through a proton-exchange membrane on their way to the cathode. The cathode itself is exposed to air. When the hydrogen ions, the oxygen from the outside air, and the generated electrons all mix, water is created.

Halina Z.