The production of hydrogen which results from the dissociation by light of water into molecular hydrogen and oxygen. This process is observed in cyanobacteria and microalgae. [ GOC:mengo_curators http://www.ncbi.nlm.nih.gov/pubmed/20395274 http://www.ncbi.nlm.nih.gov/pubmed/20692761 ]
Synonyms: hydrogen biosynthesis via biophotolysis