Abstract: The feasibility of using CO2 from a concentrated source to grow microalgae is limited by the high cost of CO2 capture and transportation, as well as significant CO2 loss during algae culture. Another challenge is the inability of algae in using CO2 during night while CO2 is continuously produced from the source. To address these challenges, this invention provides a process in which CO2 is captured as bicarbonate and used as feedstock for algae culture. Then the carbonate is regenerated in the algae culture process as absorbent to capture more CO2, which is converted to bicarbonate for use as feedstock, etc. This process significantly reduces carbon capture costs since it avoids the energy for carbonate regeneration. Also, transporting a solid or aqueous bicarbonate solution has a much lower cost than transporting compressed CO2, and using bicarbonate provides a better alternative for CO2 delivery to algae culture systems than supplying CO2 gas.