Bio-Electrochemical Systems for Simultaneous Wastewater Treatment and Green Hydrogen Production in a Decarbonized Energy Transition

Microbial electrolysis cells (MECs) are used in this study to cleanse wastewater and produce green hydrogen in a decarbonised energy transition framework. The system produced steady hydrogen generation rates surpassing 18 L m⁻² d⁻¹ with ≥ 95% purity, COD elimination, and energy efficiency under fluctuating influent circumstances by using soft-sensor validation, forecasting, and supervisory control methodologies. MEC-derived hydrogen reduced global warming potential by 52% compared to traditional steam methane reforming, demonstrating its environmental benefits. However, difficulties such electrode passivation, membrane fouling, and cost fluctuation (2.1–3.8 $ kg⁻¹) require long-term durability research and techno-economic optimisation. MECs show promise for energy-positive wastewater treatment, cyclic resource recovery, and carbon-neutral hydrogen generation.