Decision making with analytical hierarchy process approach to select feedstock type for bioethanol production: Is 3G more sustainable than others?

Abstract

Feedstock selection for bioethanol production is challenging because of the multidimensional considerations of the wide range of resources. The present study applies the analytical hierarchy process (AHP) for the first time to select the most sustainable feedstock type for bioethanol production based on 28 sub-criteria categorized under four main criteria, including technical, economic, environmental, and social. The method included the use of literature surveys, brainstorming, and expert consultation. Expert opinions revealed that the most important subcriteria within these four main criteria are fuel product quality, value-added by-product formation, impact on biodiversity, and contribution to the circular economy. Overall scores suggest that the third-generation feedstock, which is algal biomass, is economically more sustainable and environmentally friendly than the other feedstocks evaluated in the present study. Because of the environmental damage caused by chemicals used for pretreatment, the score on the environmental aspect of lignocellulosic bioethanol is slightly lower than that of algal bioethanol. The application of AHP enabled the comparison of three different generations of bioethanol production in a scientifically acceptable manner and reached a reliable decision that can be used by governments and stakeholders in establishing future renewable energy policies.