An energy analysis of first to third-generation bioethanol production in Brazil: the potential for CO<SUB align="right">2 emissions

Abstract

First (1G), second (2G) and third-generation (3G) ethanol industrialisation produces greenhouse gas (GHG) emissions and increases carbon dioxide (CO2) levels in the atmosphere. In this study, a life cycle assessment (LCA) concluded that hydrolysis and filtration processes have the largest environmental impact, and despite a trend of increased discharge generated by electricity related to 3G introduction, thermodynamic processes still show the highest emissions. These results demonstrate the importance of developing a strong technology base in biofuel industrialisation, predominantly due to the vast potential of 3G production, which increasingly requires higher energy consumption and more efficiency from the industrial system. As such, the aim of this paper is to assess the environmental impact caused by CO2 emissions in 1G, 2G and 3G ethanol production.