Life Cycle Assessment of Bioethanol Production from Sweet Potato (Ipomoea batatas L.) in an Experimental Plant

Abstract

First-generation bioethanol production from fermentation is a widely applied technology, with the United States of America and Brazil being the global leaders. However, several concerns regarding the widespread production of biofuels have arisen, particularly its environmental impacts. To address this issue, this study details the environmental impacts of the production of fist-generation bioethanol from sweet potato (Ipomoea batatas L.) in a pilot scale facility, using the Life Cycle Assessment (LCA) methodology. Cultivation and transformation of sweet potato into bioethanol are considered in the system boundaries. The background data for the life cycle inventory were mainly obtained from the Ecoinvent 3.1 database and considered both literature and field data. The SimaPro software was used to perform the impact assessment considering the CML IA baseline 3.02 method. Three different agricultural waste scenarios are also considered and compared to evaluate the best-case scenarios. In addition, sensitivity analysis and comparison with other similar studies are thoroughly explored. Overall, the analyzed production system has lower impacts than indicated in similar studies, but considering its pilot scale, improvement of its environmental impacts is necessary, which might be addressed with larger scale and centralized support systems regarding transportation and other aspects. Based on the results, several recommendations to decrease environmental impacts are also listed.