Recent Advances in Biohydrogen Production from Wastewater for Enhanced Bio-Hydrogen Production

Rapid exhaustion of fossil fuel resources underscores an urgent global transition towards sustainable energy systems, with biohydrogen from wastewater emerging as a pivotal solution. Advances in biological hydrogen production illustrate significant progress in reactor technology, microbial consortia optimization, and process integration, yet achieving commercially viable synthesis rates remains a formidable challenge. Exploiting mixed microbial cultures and integrating artificial intelligence for reactor control enhance operational stability and scalability, particularly when employing wastewater substrates. To realize the full potential of biohydrogen, future research must focus on precision engineering of bioreactors, metabolic pathway enhancement, and robust process modelling- all guided by lifecycle and techno-economic analyses. Overcoming biochemical and operational bottlenecks will not only enable cost-effective large-scale production but also contribute decisively to greenhouse gas mitigation and circular resource management. By addressing these integrated scientific, technological, and economic dimensions, biohydrogen production from wastewater can be positioned as a transformative technology for sustainable energy futures. This review highlights technological progress in fermentative, phototrophic, and electrochemical processes, summarizes influential operational parameters, and discusses prospects for scale-up and economic viability.