Enhancing power generation of scale-up microbial fuel cells by optimizing the leading-out terminal of anode

Low power output and high cost are two major challenges for scaling up microbial fuel cell (MFC). The ohmic resistance of anode increasing as MFCs scale up can be one of main reasons for power density decrease. We present a simple model to simulate power loss and potential drop distribution caused by ohmic resistance of carbon mesh anodes with different dimensions and various leading-out terminals. We also conduct experiments to confirm the simulation work and the large impact of anode ohmic resistance on large-scale MFCs by varying leading-out configurations. The simulation results show that the power loss with an anode size of 1 m(-2) can be as high as 4.19W at current density of 3 A m(-2), and the power loss can be decreased to 0.04 W with optimized configuration of leading-out terminals and to 0.01 W by utilizing brass mesh as anode material. The experiments well confirm the simulation results with the deviations less than 11.0%. Furthermore, the experiment results also show that more than 47.1% of the power loss from small-scale to large-scale MFC comes from bad-leading-out terminal. These results demonstrate that leading-out terminal of anode is one of the key factors for scaling up MFC. (C) 2013 Elsevier B.V. All rights reserved.