Microalgae-derived hydrogen production towards low carbon emissions via large-scale outdoor systems

Hydrogen as a clean fuel is receiving attention because it generates only water and a small amount of nitrogen oxide upon combustion. Biohydrogen production using microalgae is considered to be a highly promising car-bon-neutral technology because it can secure renewable energy while efficiently reducing CO2 emissions. However, previous studies have mainly focused on improving the biological performance of microalgae; these approaches have struggled to achieve breakthroughs in commercialization because they do not heavily consider the complexity of the entire production process with microalgae, including large-scale cultivation, biomass harvest, and biomass storage. This work presents an in-depth analysis of the state-of-the-art technologies focused on large-scale cultivation systems with efficient downstream processes. Considering the individual processes of biohydrogen production, strategies are discussed to minimize carbon emissions and improve productivity simultaneously. A comprehensive understanding of microalgae-derived biohydrogen production suggests future directions for realizing environmental and economic sustainability.

Automated summary

This study provides an in-depth analysis of microalgae-based biohydrogen production, focusing on large-scale cultivation systems and efficient downstream processes. Strategies to reduce carbon emissions and improve productivity simultaneously are discussed by considering each production process. This research has significant implications for achieving environmental and economic sustainability.