Biohydrogen production from microalgal biomass: Energy requirement, CO2 emissions and scale-up scenarios

The H2 yield obtained was 7.3 g H2/kg of S. obliquus dried biomass. The results show that the production of biohydrogen required 71-100 MJ/MJH2 and emitted about 5-6 kg CO2/MJH2. Other studies and production technologies were taken into account to discuss an eventual process scale-up. Increased production rates of microalgal biomass and biohydrogen are necessary for bioH2 to become competitive with conventional production pathways.