Algae-Assisted Microbial Fuel Cell for Electricity Generation from Food Waste

Microbial Fuel cells (MFCs) are bio-electrochemical systems that utilize microbes as biocatalysts in metabolizing organic substances to generate electricity. Microbial fuel cells are sustainable alternatives for electricity generation for small-scale applications. In an algae-assisted MFC, the electrons released from the anode chamber are passed to the cathode where the electrons are accepted due to the presence of oxygen from the photosynthesis reaction of algae. In this work, the dual-chambered algae-aided MFC was constructed to process 0.5 kg of composted food waste at the anode, and algae lake water at the cathode. The setup was operated for about 6 months without the addition of extra nutrients albeit giving a decreased voltage due to gradual depletion in organic content. The maximum voltage output was found to be in the range of 786 mV and a maximum current of 200 μA was obtained with an LED load on the 16th day for an aluminum electrode. A large-scale setup of 5 kg capacity was constructed and connected via Nafion membrane resulting in 1.061 V open circuit voltage. A series setup linking three MFCs of 0.5 kg capacity each was built, resulting in a maximum of 2.16 V open circuit voltage. Hence, the algae-assisted microbial fuel cell can be a viable solution for the production of algal biomass, carbon sequestration, food waste treatment, and as a power source.