Contextualizing ethanol avoided carbon emissions in Brazil

Abstract

AbstractWe propose to compare avoided emissions from ethanol use in Brazil with emissions caused by the use of fossil fuel, and by land use changes, specifically Amazon deforestation. The avoided emissions of CO2 in Brazil due to ethanol use in 2008 ranged from approximately 9 to 12 Tg C yr−1. These values are an order of magnitude higher than the amount of carbon that could be potentially sequestered in soils if sugarcane cultivation in Brazil switches completely to mechanized harvesting, and two orders of magnitude higher than the carbon emissions in soils cultivated with sugarcane and that undergo harvest with burning. In relation to fossil fuel emissions, ethanol avoided emissions are equivalent to 20–30% of the carbon emissions associated with the use of gasoline and diesel in the transportation sector, and to approximately 10% of the total use of fossil fuel in the country. When compared with the carbon emissions from Amazon deforestation ethanol avoided emissions are again one order of magnitude lower. We conclude that ethanol avoided emissions are relatively important within the transport sector, but are still incipient if compared with the emissions from total fossil fuel combustion and emissions from deforestation indicating that climate mitigation efforts in Brazil needs to focus outside of biofuel production. Consequently, we suggest that Brazil develop equally strong actions towards increased energy efficiency use in the country and, more importantly to drastically reduce carbon emissions associated with Amazon deforestation.