In order to present the results in a comprehensive way, the same structure as in the previ­ous sections is used. Default methodological choices include A-1 (i. e., energy allocation) regarding allocation methods (based on the recommendations of the EC, 2009) and LUC-1 (i. e., set aside to cultivated land) regarding land-use change. The default choice regarding fuels blends and vehicle/fuel performance is E5-1 (i. e., ethanol used as E5, with fuel perfor­mance based on actual vehicle tests), according to the most common situation in the EU. The results showing the effect of methodological choices on the WtW net GHG emissions of bioethanol are given in Table 5. The same results are illustrated in Figure 5.

The results are presented as net GHG emissions ( as net energy use, respectively) of fuel-ethanol, expressed in kg CO2 eq./km (in MJp/km, respectively). A positive value means that the system results in a net emission of GHG over the life cycle, whereas a negative value (only one case in the selected options below) means that the system is actually capturing GHG. These are then compared to gasoline in order to assess the actual balance and the potential for reducing GHG emissions and nonrenewable primary energy use. The net GHG emissions and net energy use of gasoline are 0.237 kg CO2 eq./km and 3.493 MJp/km, respectively. Any smaller (larger, respectively) score for ethanol means that the system actually results in a reduction (an increase, respectively) of environmental impact with respect to gasoline.