Progress toward a bicarbonate-based microalgae production system.

Commercial applications of microalgae for biochemicals and fuels are hampered by their high production costs, and the use of conventional carbon supplies is a key reason. Bicarbonate has been proposed as an alternative carbon source due to its potential advantages in lower carbon supply costs, convenience for photobioreactor development, biomass harvesting, and labor and energy savings. We review recent progress in bicarbonate-based microalgae cultivation, which validated previous assumptions, suggested further advantages, and demonstrated potential to significantly reduce production cost. Future research should focus on improving production efficiency and reducing energy inputs, including optimizing photobioreactor design, comprehensive utilization of natural power, and automation in production systems. For microalgae production systems, bicarbonate is a better carbon supply than bubbled CO 2 gas in terms of carbon utilization efficiency, photobioreactor development, energy saving, and biomass harvesting. The carbon supply is the bottleneck in developing photobioreactors for low-cost microalgal biomass production, in contrast to the heterotrophic process, which is limited by oxygen supply. Recent progress suggests the potential of the bicarbonate-based integrated carbon capture and algae production system, to significantly reduce production costs and energy inputs in microalgae cultivation. Comprehensive utilization of natural power is a promising approach to further decrease energy consumption and improve the efficiency of the microalgae cultivation process in the future. [ABSTRACT FROM AUTHOR]