Microalgae Mass Production Methods

This article reviews the performance, special features, and technical and/or economic barriers of various microalgae mass production methods including open-pond, photobioreactor, and immobilized culture systems. Open ponds are the least expensive among the three systems; however, issues of vulnerable species contamination, low productivity, high harvesting cost, and large volume of water loss have to be addressed. High biomass productivity and cell density, reduced contamination, and better use of CO2 are some advantages of photobioreactor systems, but the prohibitively high construction cost of photobioreactors still limits commercialization of such systems. Immobilized algae culture systems have great potential to obviate the harvesting problem of open ponds and photobioreactors and enhance biomass productivity; however, high material cost and limited choices of algae species require more investigation. Economics of algae biofuel manufacturing are also discussed. Algae biomass productivity, lipid content, and petroleum price are decisive factors in the economic viability of algae biofuels.