Biohydrogen production as a potential energy resource – Present state-of-art

Biological hydrogen production is one of the most challenging areas of technology development for sustainable gaseous energy generation. The future of biological hydrogen production depends not only on research advances, i.e. improvement in efficiency through genetically engineered microorganisms and/or the development of bioreactors, but also on economic considerations, as compared to fossil fuels, social acceptance, and the development of hydrogen energy systems. The present study critically updates various biohydrogenation processes with special references to their merits and demerits. Different approaches towards improvement of the bioprocesses are also outlined.