Nafion, a sulfonated tetrafluoroethylene copolymer, consists of a hydrophobic fluorocarbon backbone (--CF2--CF2--) to which hydrophilic sulfonate groups (SO3-) are attached. The presence of negatively charged sulfonate groups in a nanomembrane brings about a high level of proton conductivity. In this study, Saccharomyces cerevisiae was used for production of bioelectricity in a 2-chambered microbial fuel cell (MFC). We selected 9- cm2 Nafion 117 and Nafion 112 as nanomembranes to transport the produced proton from the anode chamber to the cathode compartment at ambient temperature and pressure. Initial glucose concentration was 30 g/L. The maximum obtained voltage, current, and power density for Nafion 117 were 668 mV, 60.28 mA/m2, and 9.95 mW/m2, respectively. For Nafion 112, those results were 670 mV, 150.6 mA/m2, and 31.32 mW/m2, respectively. ; Nafion, a sulfonated tetrafluoroethylene copolymer, consists of a hydrophobic fluorocarbon backbone (--CF2--CF2--) to which hydrophilic sulfonate groups (SO3-) are attached. The presence of negatively charged sulfonate groups in a nanomembrane brings about a high level of proton conductivity. In this study, Saccharomyces cerevisiae was used for production of bioelectricity in a 2-chambered microbial fuel cell (MFC). We selected 9- cm2 Nafion 117 and Nafion 112 as nanomembranes to transport the produced proton from the anode chamber to the cathode compartment at ambient temperature and pressure. Initial glucose concentration was 30 g/L. The maximum obtained voltage, current, and power density for Nafion 117 were 668 mV, 60.28 mA/m2, and 9.95 mW/m2, respectively. For Nafion 112, those results were 670 mV, 150.6 mA/m2, and 31.32 mW/m2, respectively.