Microalgae are considered to be one of the most feasible options that have the potential to serve as a major feedstock for biofuels and bio-products production. However, the economic viability of com- mercial scale production remains questionable by many researchers and investors. There are several uncertainties in the technology for microalgae growing and harvesting, and the extraction of algal oil, which makes it difficult to identify the technology most suitable for minimizing cost and maximizing profits. Therefore, there is a need to carry out parametric analyses to identify the influence of system configuration and process on the economic viability. This study establishes an economic analysis for a microalgae oil production pathway to determine the minimum cost of producing algal oil. Taking the capital and operating costs parameters from the economic analysis, some of the key parameters are changed across a range of values and their influence on the final cost of algal oil is analysed. Each of the parameters is analysed across a range of production scale from 5 to 75 g/m2/d. The results show that the most important cost-driving parameters are the pond cost (especially the liners) and the harvesting costs, and that the costs can be reduced from £1.87/L to £1.58/L for a growth rate of 25 g/m2/d and £1.34/L for a growth rate of 50 g/m2/d. This ultimately suggests that to achieve economic viability, improvements to cell biology (both growth rates and lipid content) and reducing systems unit costs while improving performance will be required together.
algal oil, biofuels, economic cost, parametric analysis
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