The potential of microalgae for carbon capture and sequestration

Abstract

Microalgae have been highlighted as a contributor to CO2 sequestration due to their efficient photosynthetic system. However, calculations on their actual potential for CO2 sequestration are often lacking. Here, we calculated the potential of microalgae for the capture of CO2 by integrating it with a large emitter (gas-based energy plant) and a low emitter (dairy farms), and also discussed if such integrated systems can be considered as carbon sequesters given that the final use of the biomass often quickly releases the captured CO2. Moreover, the CO2 footprint of microalgal systems is highlighted as a critical point of attention for future developments. Such considerations are of utmost importance to avoid false promises that ultimately harm this sector, as large investments are made following untruthful claims that, when proven wrong, result in a loss of interest. Finally, key definitions are proposed to improve clarity and help in such discussions.

Keywords

• Microalgae
• CO2 sequestration
• CO2 capture
• CO2 neutrality
• Industrial symbiosis
• Circular economy