Sugarcane ethanol: Contributions to climate change - BAFF

Chapter 5
3. Environmental indicators
�e environmental sustainability is evaluated through indicators such as carbon, water, soil,
agrochemicals, biodiversity and by-products.
3.1. Greenhouse gases (GHG) balance
One of the goals of using biofuels is to contribute with net reduction of GHG emissions
and thus not a�ecting carbon stock negatively in di�erent sub-systems of production,
below and above ground biomass (roots, branches and leaves) and in the soil (carbon �xed
in clay, silt, sand and organic matter). Figure 4 shows that ethanol from sugarcane reduces
86% of the GHG emissions when compared to gasoline. It has also a leading performance
when compared to other biofuels from other feedstocks. In addition the energy e�ciency
di�erence is even greater: 9.3 against 1.4 to 2.0 of other biomasses (Figure 5).
Sugarbeet, EU
Sugarcane, Brazil
Wheat, EU
Corn, US
Rapeseed, EU
Second generation
0 20 40 60 80 100
Figure 4. GHG emissions avoided with ethanol or biodiesel replacing gasoline. Source: International
Energy Agency (IEA/OECD, 2006).
9.3
sugercane
2.0 2.0
wheat
sugarbeets
Figure 5. Energy output per unit of fossil fuel consumption in the production process. Source: World
Watch Institute (2006) and Macedo et al. (2008).
120 Sugarcane ethanol
1.4
corn