Advances in Microbial Fermentation for Sustainable Biohydrogen Production

ABSTRACT

The Earth's mean global temperature is closely linked to atmospheric greenhouse gas (GHG) concentrations, which have increased steadily since the Industrial Revolution. To meet rising energy demands while mitigating climate change, countries are accelerating the adoption of renewable and sustainable energy sources. Hydrogen has emerged as a promising clean energy carrier, with China being the world's largest producer. This review critically evaluates microbial fermentation as a sustainable route for hydrogen production. Recent advances in bioreactor design, fermentation pathways, substrate utilization, and metabolic engineering are discussed to enhance microbial efficiency. The integration of biohydrogen production with renewable energy systems is examined to improve sustainability. Key challenges related to feedstock variability, scalability, and economic feasibility are highlighted, along with future strategies for large‐scale, high‐purity biohydrogen production.