BACKGROUND Electricity production in single-anode/cathode MFCs fed with simulated synthesis gas (syngas) as the sole electron donor has recently been demonstrated. This study evaluated the ability of a multi-anode/cathode MFC fed with syngas to achieve improved volumetric efficiency at several operating temperatures and electrode arrangements. RESULTS A maximum power density of 33 mW LR-1 (normalized to the anodic compartment volume) and a coulombic efficiency (CE) of 43% was achieved at an operating temperature of 37 degrees C. MFC operation at 50 degrees C resulted in a much lower power density of 10 mW LR-1 and a CE of 15%. The MFC power density was greatly impacted by the electrode arrangement and the highest power density was achieved in a three anode-two cathode (3A-2C) arrangement. CONCLUSION The multi-electrode design enhanced the performance of a syngas-fed MFC, which could have major economic and operational implications for designing large-scale syngas-fed MFCs. The MFC performance at elevated temperatures was restricted by low microbial activity, implying that a thermophilic rather than a mesophilic inoculum might be required for successful operation under thermophilic conditions. (c) 2013 Society of Chemical Industry