were generated according to Eqns. 4 and 5. The cycling time between the OCV and different applied Rext values was 1 to 2 hours, which was sufficient for a healthy MFC of the same design to reach a stable value in the short-term. Initially (t=42 days), the power density curves showed a typical monotonic approach to maximum power density (Pmax=360 mW m -2 ), and no overshoot was observed at high current densities, similar to measurements observed during the first month.