The sustainability of ethanol production from sugarcane

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Energy Policy 36 (2008) 2086– 2097

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Energy Policy
journal homepage: www.elsevier.com/locate/enpol

The sustainability of ethanol production from sugarcane
´ Jose Goldemberg Ã, Suani Teixeira Coelho, Patricia Guardabassi
˜ ˜ CENBIO—The Brazilian Reference Center on Biomass, IEE—Institute of Eletrotechnics and Energy,USP—University of Sao Paulo, Sao Paulo, Brazil

a r t i c l e in f o
Article history: Received 4 September 2007 Accepted 21 February 2008 Available online 7 April 2008 Keywords: Sugarcane ethanol Sustainability Environment

a b s t r a c t
The rapid expansion of ethanol production from sugarcane in Brazil has raised a number of questions regarding its negative consequences and sustainability. Positiveimpacts are the elimination of lead compounds from gasoline and the reduction of noxious emissions. There is also the reduction of CO2 emissions, since sugarcane ethanol requires only a small amount of fossil fuels for its production, being thus a renewable fuel. These positive impacts are particularly noticeable in the air quality improvement of metropolitan areas but also in rural areas wheremechanized harvesting of green cane is being introduced, eliminating the burning of sugarcane. Negative impacts such as future large-scale ethanol production from sugarcane might lead to the destruction or damage of high-biodiversity areas, deforestation, degradation or damaging of soils through the use of chemicals and soil decarbonization, water resources contamination or depletion, competitionbetween food and fuel production decreasing food security and a worsening of labor conditions on the fields. These questions are discussed here, with ˜ the purpose of clarifying the sustainability aspects of ethanol production from sugarcane mainly in Sao Paulo State, where more than 60% of Brazil’s sugarcane plantations are located and are responsible for 62% of ethanol production. & 2008 ElsevierLtd. All rights reserved.

1. Introduction Ethanol is produced through the fermentation of agricultural products such as sugarcane, corn, wheat, sugar beet and cassava, among others. The great majority of ethanol produced in the world is from sugarcane, mainly in Brazil, and corn in the United States (which together account for 35.4 million cubic meters, about 72% of the world’s production) (UNICA,2008; EIA, 2008). The Brazilian Alcohol Program (Proalcool) was established in 1975 for the purpose of reducing oil imports by producing ethanol from sugarcane. Ethanol’s production rose from 0.6 million cubic meters from that year to 18 million cubic meters in the 2006/2007 season, with increasing agricultural and industrial productivities. In Brazil, ethanol is used in cars as an octaneenhancer and oxygenated additive to gasoline (blended in a proportion of 20%, E-20, to 26%, E-26, of anhydrous ethanol in a mixture called gasohol), in dedicated hydrated ethanol engines or in flex-fuel vehicles running with up to E-100. Only in the year 2003, the emission of 27.5 million tons of CO2 equivalent in the atmosphere was avoided due to the gasoline replacement by ethanol (Macedo, 2005).Since February 1999, ethanol prices are no longer controlled by the Government; hydrated ethanol is sold for 60–80% of gasohol’s price at pump stations, and nowadays Brazilian ethanol is competitive internationally with gasoline at Rotterdam prices and there are no subsidies to producers, due to significant reductions in production costs (Goldemberg et al., 2003; Coelho, 2005). However, the expansionof ethanol production from sugarcane ˜ envisaged in Brazil (particularly Sao Paulo) to supply an expanding market as well as exports to other countries has raised concerns on its sustainability. Therefore here we will discuss the sustainability aspects of ethanol production, namely environmental and social aspects as well as sustainability criteria, as suggested by the Cramer Commission...
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