## 4 Results
### Comparative Analysis of CBA Methodologies and Results
#### Calculation of Greenhouse Gas Emissions and Costs According to the CBA Methodology in Austria
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**ID** & **Unit** & **A** & **FR** & **DE** & **N** & **SE** & **CH** & \
\begin{tabular}{c} **Average** \\ **Value** \\ \end{tabular} &
\begin{tabular}{c} **Median** \\ **Value** \\ \end{tabular} \\ \hline
1 & petrol & kg/L & 0.742 & 0.745 & 0.742 & 0.742 & 0.742 & 0.737 & 0.742 & 0.742 \\
9 & petrol 2S & kg/L & 0.742 & 0.745 & 0.742 & 0.742 & 0.737 & 0.742 & 0.742 \\
2 & diesel & kg/L & 0.832 & 0.855 & 0.832 & 0.832 & 0.832 & 0.83 & 0.836 & 0.832 \\
31 & biodiesel & kg/L & 0.883 & 0.883 & 0.881 & 0.881 & 0.881 & 0.86 & 0.878 & 0.881 \\
30 & vegetable oil & kg/L & 0.92 & 0.92 & 0.92 & 0.92 & 0.92 & 0.92 & 0.920 & 0.920 \\
21 & ethanol (bio) & kg/L & 0.794 & 0.794 & 0.7894 & 0.7894 & 0.794 & 0.792 & 0.792 \\
23 & E85 & kg/L & 0.7862 & 0.788 & 0.78229 & 0.78229 & 0.78229 & 0.78545 & 0.784 & 0.784 \\
3 & CNG & kg/Nm\({}^{3}\) & 0.716 & 0.69 & 0.716 & 0.716 & 0.716 & 0.795 & 0.725 & 0.716 \\
51 & biogas & kg/Nm\({}^{3}\) & 0.716 & 0.69 & 0.716 & 0.716 & 0.795 & 0.725 & 0.716 \\
6 & LPG & kg/L & 0.54 & 0.538 & 0.6 & 0.6 & 0.6 & 0.54 & 0.570 & 0.570 \\
53 & LNG & kg/Nm\({}^{3}\) & 0.716 & 0.452 & 0.716 & 0.716 & 0.716 & 0.716 & 0.672 & 0.716 \\
52 & propane & kg/Nm\({}^{3}\) & 0.716 & 0.538 & 0.716 & 0.716 & 0.716 & 0.716 & 0.686 & 0.716 \\
5 & electricity & not specified & 0 & 0 & 0 & 0 & 0 & 0 & 0.000 & 0.000 \\
8 & hydrogen & not specified & 0 & 0 & 0 & 0 & 0 & 0.000 & 0.000 \\
4 & petroleum & kg/L & 0.8 & 0.8 & 0.8 & 0.8 & 0.799 & 0.800 & 0.800 \\ \hline \hline \end{tabular}
\end{table} 
Table 21: Comparison of the density of selected fuels according to the HBEFA methodology [53]. Figure 2: Comparison of the density of petrol and diesel according to selected methodologies and standards (kg/L), the authors based on [53; 54; 56]. The tables below compare the density values of the selected fuels under the different methodologies and standards against the values in the CBA methodology in the Slovak Republic. Table 22 contains the share of CBA SR fuel density in % of the fuel density value from other sources. Table 23 contains the difference in the CBA SR fuel density to the fuel density value (%) from other sources. The fuel density value influences the amount of pollutants and greenhouse gases released by road transport and, thus, the associated external costs. Other sources of information on the density value of selected fuels may be  
* Slovnaft Refinery as the largest supplier of fuel in the Slovak Republic;  
\(\circ\)\(\circ  
We recommend adjusting the categories of road vehicles for pollutant emissions and associated external costs. The application of a clear categorization of road vehicles, including a separate category for 'buses' (not merging several vehicle categories into groups). A comparison of the vehicle categories used by each country in the CBA methodologies for pollutant and GHG emissions and associated costs shows that the Czech Republic uses the same vehicle categorization for both pollutant and GHG emissions. This is not the case in the CBA methodology in the Slovak Republic. It is not clear from Table 42 of the Slovak methodology whether the category \"Other trucks and buses (diesel)\" includes the category of medium-weight trucks and the category of heavy-duty trucks used in Table 45 for GHG emissions. We recommend using in Table 42 of the methodology the same categorization used in Table 45, Emission Factors (g/kg) of Road Vehicles (Conventional Fuels) of the _CBA Methodology Manual_, version 1.0, as follows:  
* Passenger vehicles (petrol);
* Passenger vehicles (diesel);
* Light trucks (diesel);
* Medium-duty trucks (diesel);
* Heavy-goods vehicles (diesel);
* Buses (diesel). Both Table 42 and Table 45 of the _CBA Methodology Manual_, version 1.0, are based on the same source (_EMEP_/_EEA Air Pollutant Emission Inventory Guidebook 2019_ (I.A.3.b. Road transport)).