Feasibility Assessment of Microalgal Carbon Dioxide Sequestration Technology with Photobioreactor and Solar Collector

The aim of this study was to develop a feasibility model for microalgal carbon dioxide (CO₂) biofixation using photobioreactors equipped with solar collectors, which would evaluate the unit net cost of CO₂ mitigation as a function of the target total CO₂ mitigation cost, the available solar radiation, and the biological conversion efficiency, among others. The results showed that, to achieve the target CO₂ mitigation price of 30 US$ t^-1 [CO₂] at 40% biological conversion efficiency, the allowable net cost should be less than 2·52 US$ m^-2 yr^-1 at low-light intensity (average US location), and should be less than 3·24 US$ m^-2 yr^-1 at high light intensity (sunbelt region). The model made evident the importance of using microalgae with commercially valuable byproducts (e.g. biofuel), especially in achieving the smaller allowable unit net costs corresponding to more stringent CO₂ mitigation costs.