High intensity mass algae culture requirements and limitations

The design of algae culture units intended to maximize the growth of algae in sunlight is discussed, considering CO2 and oxygen supply, culture depth, temperature control, and cell suspension density. Emphasis is placed on photosynthesis, photorespiration, the partial processes involved, rates of oxygenation of ribulose-1.5-bisphosphate, and the net quantities of ATP and NADPH which may be utilized from a given quantity of light with regard to C4 and C3 plants. It is shown that maximum efficiencies of solar energy conversion to chemical potential energy in biomass can only be achieved when the photon flux density is the rate-limiting factor, which requires that the O2 and CO2 concentrations at the carboxylation site must be maintained such that the carboxylase reaction is proceeding near maximum rate, and the oxygenase activity is completely or nearly completely inhibited.