Applied resistance for power generation and energy distribution in microbial fuel cells with rationale for maximum power point

The present study aimed to basically understand the bioanodic function over microbial power generation and energy distribution under applied external resistance in a microbial fuel cell (MFC). External load (resistor) optimization was carried out to determine the maximum power point (MPP). After long term operation of about 25 batch cycles, the MFC which was closed with resistance at MPP resulted in a maximum power density (114 mWm−2). This observation was further supported by the anode potential profile that being lowest at MPP and maximum coulombic efficiency with 80% of substrate utilization. The energy distribution revealed that only a fraction (∼16%) of the overall chemical energy input is actually converted into net electrical energy and the energy losses were traced by polarization slope analysis. Voltammetric profiles depicted the biocatalyst activity in terms of direct electron transfer to anode as function of applied resistance.