Environmental and Economic Assessment of Bioethanol, Sugar and Bioelectricity Production from Sugarcane

The study of optimization scenarios taking into consideration not only technical and energy parameters but also economic and environmental aspects is fundamental for sustainability of biorefinery systems. This study focuses on the environmental and economic impacts of autonomous and annexed sugarcane processing plants in Brazil using an innovative framework, where computer simulation is linked to the environmental and economic assessment. Results showed that considering only the industrial processing stage for ethanol production, autonomous plant present better environmental performance. However it was not possible to establish significant differences between annexed and autonomous plants when the complete life cycle of the ethanol production from sugarcane is considered. Optimized biorefineries showed lower environmental impacts and better economic results in comparison to the base scenarios for both annexed and autonomous plants. Economic results also indicated that, in the base scenario, annexed plant presents slightly higher internal rate of return and slightly lower ethanol production costs. Optimized biorefinery scenarios showed that autonomous plant present higher internal rate of return while annexed and autonomous plants showed equivalent ethanol production costs.