Microbial electrolysis cells: Fuelling the future with biohydrogen – A review

Abstract

Biohydrogen is a prodigious energy carrier, which emerged as one of the most practical solutions to combat global warming and climate change. In this regard, the emerging microbial electrolysis cell (MEC) technology could be utilized for green hydrogen production from a wide array of organic wastes. However, scaling-up of MECs is a significant barrier due to its architectural difficulties and increased internal resistance, resulting in the higher energy requirement and cost of the MEC at pragmatic scale. Thus, the present review elucidates the mechanism, different configurations and substrates, and scaling-up potential for biohydrogen production via MEC. Moreover, the techno-economic and environmental impact of biohydrogen production through MEC from different substrates is also presented. Furthermore, microbial dynamics that govern hydrogen production rate and commercialization potential are also reviewed critically, which makes this review article the first of its kind to the best of our knowledge.