Techno-economic analysis of ethanol production from marine biomass

The purpose of this study is techno-economic analysis of ethanol production from marine biomass (macroalgae), based on 10-year time frame for plant operation. This study is different from previous similar studies considering following facts: (1) Biomass considered in this study is macroalgae or seaweed, to which technologies available for conversion of biomass to fuels have been applied in limited ways. (2) This study does not provide production cost of ethanol, but target biomass cost for macroalgae production through large-scale cultivation that is a key factor for success of macroalgae as a biomass feedstock. Currently high seaweeds price greatly limits the applicability of seaweeds as feedstocks for bioethanol production plant. To solve this issue a reduction of feedstock price seems the only option. This study develops a techno-economic model to analyze the economy of an ethanol production plant processing 100,000 MT/year (dry basis) brown algae. This study effectively defined maximum dry seaweed price (MDSP) that must be covered by large-scale seaweed production to reach a Return-On-Investment (ROI) break-even point after 10 years plant operation. The MDSP will act as target biomass cost for large-scale cultivation of macroalgae. Plant scale ups were also performed to examine the effects of plant capacity on MDSP.