Enhancing bioelectricity generation and mitigating methane emissions in paddy fields: A novel approach using activated biochar in plant microbial fuel cells

Abstract

In the innovative realm of green energy solutions, plant microbial fuel cells (PMFCs) have emerged as a promising frontier, embodying a greener technological approach. However, PMFC is not yet viable for large-scale application due to its low voltage generation. This study explores the integration of PMFC technology in paddy field, using activated biochar as electrode material to enhance voltage production while reducing methane emission. According to the findings, rice PMFCs equipped with activated biochar achieved the highest power density, reaching an impressive 106.67 mW m−2 of anode area, significantly outperforming SMFCs, which peaked at 38.28 mW m−2 when integrated with a biochar anode. Additionally, rice-PMFCs emitted 38 % less methane than the normal rice plant, while the reduction was 27.1 % for rice plants equipped with activated biochar, with no significant change in plant yield observed. Furthermore, PMFCs reduced greenhouse gas emissions by 70 % and 67 % compared to traditional coal and natural gas-based power plants, respectively. In summary, activated biochar shows promise as a potent alternative to traditional graphite electrodes in PMFCs.