Assessment of environmental and economic aspects of the integrated production of bioenergy and food

Abstract

The biorefineries of the future will be integrated complexes that make a variety of products (e.g. biofuels, chemicals, power and protein) from a variety of feedstocks. Integrated complexes have been proposed seeking efficiency improvement and synergy between bioenergy and food production. Such complexes could reduce the land demand for bioenergy and provide diversified and optimized farming systems. One example is the integrated production of soybean biodiesel and sugarcane ethanol, which has been tested in commercial scale in Brazil. The advantages of this integration are verified not only in the agriculture and industrial spheres, but also in the management and commercial areas. Nevertheless, the real sustainability of these systems will be determined by its environmental and socio-economic aspects. The objective of this project is to evaluate the economic and environmental performance of the integrated production of bioenergy and food through a sugarcane-soybean biorefinery concept, which will be compared to the traditional Brazilian system for ethanol production. In this integrated model, soybean would be cultivated in the sugarcane reforming areas, and the output products would comprise the sugarcane bioethanol, soybean biodiesel (which would be used in the sugarcane and soybean cultivation), bioelectricity, sugar, soybean meal and glycerin. The environmental aspects to be considered in this study are the fossil-renewable energy balance and the ability to mitigate GHG emissions, based on the Life Cycle Assessment method. In the economic assessment, the biodiesel production costs and the profitability of the integrated system will be investigated. It will also be preliminarily assessed the potential environmental benefits of the biodiesel production from algae employing a high CO2 concentration system, resulted from cane juice fermentation.