東アジア地域におけるバイオエタノールの国際供給の最適化

抄録

In the production of bioethanol in Asia, developed countries such as Japan have the problems of high cost and a lack of resources, while Southeast Asian countries have substantial biomass production and export potential. The purpose of this study is to optimize the international supply of bioethanol in East Asia. A linear model is developed to estimate costs, energy consumption, and carbon emissions in three processes: cultivation, conversion, and international transport. In order to consider the regional characteristics of producing countries, biomass price, electric power generation, fertilizer usage, agricultural machine usage are incorporated into the model. Optimization based on linear programming is carried out with two objective functions: minimizing cost and minimizing carbon emissions. For each objective function, the amount of supply, economic efficiency, and carbon emissions are quantitatively analyzed in three cases. One is domestic supply case where each country supplies bioethanol to domestic market. Another is Asia supply case where Asian countries supply bioethanol with international supply. The other is Asia-Brazil supply case where Brazil is included in bioethanol supply in Asia. The average supply cost of bioethanol in Asia supply case with the objective function of minimizing cost is a quarter of that in domestic supply case. The carbon emissions reduction increases by international supply. Brazil has more than 50 % share in bioethanol production in both objective functions and contributes to the reduction of carbon emissions.