Concrete-Based Dual-Chamber Microbial Fuel Cell for Continuous Power Generation

Abstract

The increasing demand for sustainable electricity generation necessitates the exploration of innovative technologies. Biomass technology is emerging as a promising alternative to address the energy crisis for low-power devices and reduce reliance on fossil fuels. One of the methods to generate energy from this biomass is by using microbial fuel cells (MFC). However, the efforts made with this technology are still mainly limited at the laboratory scale, limiting its interest and its utilization for electrical power generation. This paper presents the real-life implementation and feasibility of a dual-chamber microbial fuel cell fabricated with concrete. 15 dual-chamber reactors were manufactured, with a volume of 0.5 liters for each chamber. Inside the anodic chamber, a carbon foam measuring 4.5 x 4.5 cm² was placed and used as the anode electrode. Two different electrode materials were used for the cathode electrodes. Six reactors used 4.5 x 4.5 cm2 carbon foam while the other 9 used graphite rods of 5 mm diameter and 15 cm long. The anode chamber was inoculated with a mixture of 25% cow dung and 75% tap water and then sealed airtight. Each cathode chamber was filled with 0.5 liters of saline solution. After 7 days of manipulation, the Open Circuit Voltage (OCV) obtained from this investigation ranged from 0.415 V to 0.732 V. That reflects the successful conversion of chemical energy of this waste in the concrete-based microbial fuel cell reactor into electrical energy. The average maximum power density obtained using graphite rod cathodes was 14.15 mW/m² while an average of 20.21 mW/m² was obtained from the MFCs using carbon foam cathodes. When the MFCs were stacked together in series, a total voltage of 8.5 V was observed.