Techno-economic analysis of transportation fuels from defatted microalgae via hydrothermal liquefaction and hydroprocessing

This study describes a techno-economic analysis to evaluate the economic feasibility of transportation fuel production by hydrothermal liquefaction (HTL) of defatted microalgae followed by hydroprocessing of the resulting bio-crude. A 2000 dry tonne per day biorefinery produces 112 dam3 of gasoline-range fuels and 121 dam3 of diesel-range fuels per year. We estimate the total project investment is 504 M$ and the annual operating cost is 158 M$. The minimum fuel-selling price (MFSP) is 679 $ m−3 assuming a 10% internal rate of return assuming 30-year plant life. Sensitivity analysis shows that MFSP is most sensitive to product fuel yield indicating the relative importance of HTL conversion performance. Feedstock cost also strongly influences MFSP, which varied between 584 $ m−3 and 869 $ m−3 for feedstock cost of 33 and 132 $ dry tonne−1, respectively. A Monte-Carlo analysis suggests an 80% probability of MFSP being between 607 and 833 $ m−3.