a b s t r a c t Production of sustainable and clean energy through oxidation of biodegradable materials was carried out in a novel stack of microbial fuel cells (MFCs). Saccharomyces cerevisiae as an active biocatalyst was used for power generation. The novel stack of MFCs consist of four units was fabricated and operated in continuous mode. Pure glucose as substrate was used with concentration of 30 g l À1 along with 200 mmol l À1 of natural red (NR) as a mediator in the anode and 400 mmol l À1 of potassium permanganate as oxidizing agent in the cathode. Polarimetry technique was employed to analyze the single cell as well as stack electrical performance. Performance of the MFCs stack was evaluated with respect to amount of electricity generation. Maximum current and power generation in the stack of MFC were 6447 mA.m À2 and 2003 mW.m À2 , respectively. Columbic efficiency of 22 percent was achieved at parallel connection. At the end of process, image of the outer surface of graphite electrode was taken by Atomic Force Microscope at magnification of 5000. The high electrical performance of MFCs was attributed to the uniform growth of microor-ganism on the graphite surface which was confirmed by the obtained images.