Sustainable power generation from bacterio-algal microbial fuel cells (MFCs): An overview

Microbial fuel cells (MFCs) are bioelectrochemical devices that allow the harvesting of electricity generated during anaerobic respiration of selected bacterial species. This technology shows promise in both wastewater treatment and sustainable bioenergy conversion applications. Bacterial respiration occurs in the anaerobic anode compartment of the MFC, and is electrochemically coupled with electron acceptors in the MFC's aerobic cathode compartment. This paper summarizes the published results of bacterio-algal MFCs. The use of microalgae in MFCs has gained interest primarily due to algae's ability to photosynthesize atmospheric CO2, producing both biomass and oxygen and thereby facilitating the cathodic reaction. These phototrophic microorganisms can serve as biocatholytes in MFCs because the oxygen produced is an electron acceptor for the electrons harvested from the anode compartment. The bacterio-algal MFC can provide multiple benefits including 1) power generation, 2) wastewater treatment, 3) algal biomass cultivation and pigment production, 4) carbon dioxide assimilation, and 5) oxygen production. This review article summarizes not only successful published results of bacterio-algal fuel cells but also highlights critical operational parameters and their effect on power generation and output efficiency.