# Theoretical Framework (Module) for Short-Sea Shipping System Evaluation
## 4 Case Study of SSS and Alternative Transport Corridors  
Two ports were selected for the case study. ROPAX shipping lines and possible alternative transport corridors exist between these two ports. The ports of Kiel [33] and Klaipeda [34], between which a ROPAX shipping line operates, were selected for the research. ROPAX ships sail from both ports once a day (Figure 4) [35]. The land transport corridor between these ports can also be used (Figure 4) [36]. Each ship can carry an average of about 200 cargo vehicles at a time. The sailing time is about 19 h. The distance between the ports is about 407 nautical miles [35]. The cost of transporting one car and the terminals is about EUR 1000, so the cost of 150 vehicles is about EUR 150,000. The average power of the ferry's main engine during navigation is about 18 MW, and the relative fuel consumption is about 0.15 kg/kWh. The total fuel consumption of the ferry during navigation and at the terminals is about 60 t.  
An alternative transport system can be road transport (Figure 5). The distance between Kiel and Klaipeda is about 1530 km. The assessment assumes that one road vehicle transports about 20 t, and the average driving speed is about 70 km/h. The total driving time from Kiel to Klaipeda is about 36 h (driving time is about 24 h, and rest time is about 12 h). The average engine power of a tractor (truck) is about 280 kW, and the relative fuel consumption is about 0.12 kg/kWh. In this way, the tractor consumes about 1000 kg during the trip. When assessing the transportation of a similar cargo by ferry (150 road vehicles), the total net driving time is about 5400 h, and the total fuel consumption is about 150 tons. The average transportation cost for one vehicle is about 1.5 EUR/km, so the transportation cost would be about EUR 2300 or about EUR 345,000 for all vehicles (150 units). Figure 4: Sea route between Kiel and Klaipeda [35]. Figure 5: Motorway between Kiel and Klaipeda ports [36]. When evaluating the adopted transportation systems, parameters, and emission calculation methodologies provided in [14; 28; 29; 30; 37], using SSS and road transportation between the specified ports, the emission results obtained are presented in Table 1.  
When it is necessary to transport many cargoes or vehicles, the SSS system is in many cases much more advantageous in terms of time, cost, and environmental impact [36]. Using the comparative method presented in Chapter 3, it is possible to find out how much more advantageous the use of SSS can be compared to the use of other transport systems or to find out to what extent the use of SSS is more advantageous compared to other methods of transporting goods. The comparative index, taking into account the cost of cargo transportation between selected ports (locations), transportation time, goods distribution options, energy (fuel) costs, and additional fees for generated CO\({}_{2}\) (calculating that the fee for one generated ton is EUR 70), is presented in Table 2.  
The difference in the direct price of freight transportation using the SSS system and an alternative mode of transportation, i.e., using the road transport system, is one of the factors, and as presented in the analyzed example, the cost using the SSS system is about 2.2-2.7 times cheaper (Figure 6). Due to the fact that using the SSS system, discounts are applied when transporting larger quantities, the time of use of vehicles is significantly shortened. \begin{table}
\begin{tabular}{c c c c c} \hline
**Emission Type** & **SSS Using** & **SSS Using** & **Road Transport** & **Road Transport** \\  & **Diesel Fuel** & **LNG Fuel** & **Using Diesel Fuel** & **Using LNG Fuel** \\ \hline CO\({}_{2}\), t & 176 & 148 & 640 & 540 \\ SO\({}_{x}\), kg & 50 & 0 & 200 & 0 \\ CO, kg & 1710 & 1026 & 2520 & 1764 \\ NO\({}_{x}\), kg & 3420 & 1368 & 3360 & 2016 \\ PM, kg & 171 & 0 & 34 & 0 \\ \hline \end{tabular}
\end{table} 
Table 1: Amount of emissions generated when transporting the same amount of cargo by SSS and road transportation systems.