Waste-to-Energy Valorization: Harnessing cassava peel extract as a sustainable substrate for microalgal fuel cell bioelectricity generation

Abstract

The escalating global energy demand, coupled with environmental challenges, necessitates the development of sustainable bioenergy technologies. Cassava processing generates substantial agricultural waste, particularly cassava peels, which constitute 10-20% of tuber weight and present significant disposal challenges. Microbial Fuel Cells (MFCs) offer a promising waste-to-energy valorization pathway by converting organic waste into bioelectricity through microbial metabolism. This study investigates the potential of Cassava Peel Extract (CPE) as a low-cost, agro-waste-based substrate for sustainable bioelectricity generation using Parachlorella sp. in a double-chamber MFC system. A double-chamber MFC was constructedwith Parachlorella s . as biocatalyst, CPE supplemented with calcium carbonate as anolyte, while 0.01 M potassium ferricyanide as catholyte. System performance was monitored, and energy harvesting was evaluated by charging 2.7 V 1F supercapacitors. Results identified 5 mL as the optimal feed volume, yielding stable currents of 0.26–0.28 mA (batch) and 0.18–0.24 mA (continuous) over 40 days. Furthermore, a multi-way electrical configuration increased supercapacitor charging efficiency by 73% compared to a one-way setup. These findings establish Parachlorella sp. as an effective agent for cassava waste valorization and contribute to the circular bioeconomy by transforming agricultural waste into renewable energy, offering a sustainable solution for both waste management and clean energy production.