Patent ID: 7732174

Claim:
A method of using sequential chemostat culture vessels to provide continuous H 2 production, in which photosynthetic O 2 evolution and H 2 photoproduction are separated physically into two connected bioreactors, comprising; a) growing a microorganism culture able to continuously generate H 2 by photosynthetically producing cells at about the early-to-late log state in a first photobioreactor operating as a sulfur chemostat under aerobic and/or anaerobic conditions; b) continuously feeding cells from the first photobioreactor to a second photobioreactor operating under anaerobic conditions and sulfur deprivation conditions to induce hydrogenase and H 2 photoproduction to provide continuous cultivation of said microorganism's cells in the first photobioreactor and constant H 2 production at a stable rate in the second photobioreactor; and c) collecting the H 2 gas from the second photobioreactor.