Sustainability assessment of large-scale ethanol production from sugarcane Consuelo L.F. Pereira a , Enrique Ortega b, * a Ecocert Brasil, R. Osni Ortiga 949, CEP 88062-450, Floriano ´polis, SC, Brazil b School of Food Engineering, State University of Campinas, CP 6121 CEP 13083-862, Campinas, SP, Brazil Keywords: Emergy analysis Life cycle assessment Biofuels Ethanol abstract The present study assesses the sustainability of ethanol produced from sugarcane and examines the environmental feasibility of a large-scale production through the use of: fossil fuel embodied energy and Emergy Assessment including farm and industrial production phases. The study indicates that about 1.82 kg of topsoil eroded, 18.4 l of water and 1.52 m 2 of land are needed to produce 1 l of ethanol from sugarcane. Also, 0.28 kg of CO 2 is released per liter of ethanol produced. The energy content of ethanol is 8.2 times greater than the fossil-based energy required to produce it. The transformity of ethanol is about the same as those calculated for fossil fuels. The Renewability of ethanol is 30%, a very low value; other emergy indices indicate important environmental impacts as well as natural resources consumption. The results obtained indicate that sugarcane and ethanol production present low renewability when a large- scale system is adopted. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction Biofuels have been presented as an important option for energy supply, notably as renewable substitutes for fossil fuels. They are considered a renewable and endless resource, since they are produced from biomass, usually from an agricultural crop, reputed as renewable. Besides, it is a current belief that, by replacing oil products, their use could reduce greenhouse gases emissions. Yet, there are some discordant voices that point out that any biomass production and industrial transformation require the use of fossil fuel energy – in the form of fertilizers, agrochemicals, machinery, and for inputs and raw material transportation. Moreover, mono- culture might result in soil degradation, natural ecosystem destruction and, in this case, there is a competition for the use of arable land between the production of energy and food crops. Ethanol produced from sugarcane has been used as an auto- mobile fuel for many years in Brazil. Anhydrous form ethanol (99.3  GL) has been added to gasoline (up to 25%, volume/volume) while the hydrous form (96  GL) has been used as a sole fuel since 1978, with the introduction of cars powered solely by ethanol. Today, all the gasoline sold has 25% of added anhydrous ethanol; 16% of the Brazilian fleet is comprised of flex automobiles that can use either gasoline or ethanol [1]. To supply this market, along with the sugar market, 7.1 million hectares (71 thousand square kilo- meters) were used to grow sugarcane in 2006. In the same year, the Brazilian production of ethanol was 15.8 billion liters, 85% of which was used within the internal market [2]. The objective of this study was to assess the sustainability of ethanol produced in large-scale from sugarcane and to examine its environmental feasibility through the use of fossil fuel embodied energy and Emergy Assessment. 2. Methods The embodied energy analysis method (EEA) considers the energy from petroleum necessary to prepare the industrial inputs used in a transformation process. This method was the precursor of Emergy Analysis. Emergy Analysis (EMA) has been frequently used to evaluate production systems, mainly because it takes into account all the inputs necessary to drive a process: nature’s contributions (rain-water, ground-water, soil,sediments, and biodiversity) and the inputs supplied by human economy (chemicals, raw-materials, machinery, fuel, services, payments, etc.). Besides, EMA’s results provide quantitative information about the impact caused by the studied system in the associated environment and it can be used to calculate its carrying capacity, or support area [3,4]. Life cycle assessment (LCA) adopts a ‘‘cradle-to-grave’’ approach by evaluating all stages of a product’s life, from raw material acquisition to waste disposal, identifying, quantifying and evalu- ating the cumulative environmental impacts (resources consump- tion, and emissions and wastes release into the environment) * Corresponding author. Tel.: þ55 19 3521 4035. E-mail addresses: consuelo@ecocert.com.br (C.L.F. Pereira), ortega@fea.unicamp. br (E. Ortega). Contents lists available at ScienceDirect Journal of Cleaner Production journal homepage: www.elsevier.com/locate/jclepro ARTICLE IN PRESS 0959-6526/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.jclepro.2009.09.007 Journal of Cleaner Production xxx (2009) 1–6 Please cite this article in press as: Pereira CLF, Ortega E, Sustainability assessment of large-scale ethanol production from sugarcane, J Clean Prod (2009), doi:10.1016/j.jclepro.2009.09.007