E.E. Powell, J.C. Bolster, G.A. Hill, R.W. Evitts
microbial fuel cell, photosynthesis, CO2 neutral, bioethanol, electricity generation
A completely biological microbial fuel cell (MFC), using photosynthetic growth at the cathode and yeast fermentation at the anode, has been developed and operated successfully for the first time. The photosynthetic culture, Chlorella vulgaris, was employed as the electron acceptor in the cathodic half cell, while the yeast fermentation culture, Saccharomyces cerevisiae, was used as the electron donor in the anodic half cell. The potential difference across the two cultures resulted in an entirely microbial electricity generation system. Loading effects and power generation for the complete MFC have been examined. The addition of supplemental dextrose to the yeast at the anode of the MFC significantly improved the electrical output of the system. Enriching the feed air bubbled into the cathode cell with 10% CO2 significantly increased the algae biomass growth and the voltage. This novel MFC has potential importance in the clean technology field. It is a completely biological fuel cell. Growth of C. vulgaris at the cathode consumes significant CO2. This could include the CO2 produced by the yeast at the anode during operation, making this a carbon dioxide neutral power generation technology. In addition, the S. cerevisiae cells at the anode produce significant amounts of ethanol during growth.