## 4 Case Study: Economic Analysis 600 TEU Fuel Transition from MFO to LNG
### Cost Assessment for Retrofitting 600 TEU Container Vessel  
This analysis was centered on the assumption of retrofit cost in 2022, which encompasses main, and auxiliary engines, fuel gas supply system and installation. The conversion cost is USD 200 to USD 340 per HP, based on the upper bound assumption [39] Furthermore, this retrofit has an estimated cost of USD 3,600,000. Figure 10 is adapted from [PERSON] et al. [26] and illustrates retrofit costs for various fuel types. \begin{table}
\begin{tabular}{c c} \hline \hline
**New Build with MFO Fuel** & **New Build with LNG Fuel** \\ **(MUSD)** & **(MUSD)** \\ \hline
9,180,000 & 11,180.000 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Estimated new build 600 TEU container vessel. Figure 9: OPEX cost for various container vessels. [PERSON] et al. stated that using gas as fuel reduces the deposit of organic material in the combustion chamber [43]. The reduction in hydrocarbons and other particles from the fuel affects its mass deposit. Some studies carried out on LNG as a marine fuel stated that the maintenance cost is reduced because a small amount of lubricating oils is applied on the spare part compared to the engine system using MFO or HFO. By reducing emissions, the annual expenditure determines the entire cost of natural gas applied on the main fuel onboard, including the capital expenses due to conversion [25]. Based on OPEX per year, the equivalent loading and offloading per year is 312 days. This is because the sailing duration from Jakarta to Singapore lasts for approximately three days. Based on an interview session held with one of the owners, the loading and offloading duration is usually two days for one trip, with the assumption that the in-container at the terminal is 60 containers/day. Table 3 shows the engine information that it used for investment calculation which consist of data regarding power, number of unit, specific fuel oil consumption and type of fuel. Table 4 shows that the total OPEX/year after retrofit is usually within the range of minimum, average and maximum variables. All tend to be reduced according to the acquired data. This Table 4 illustrate operation cost of spares, repair, maintenance, and lubricant based on the Moore Maritime Index [34]. The total OPEX per year was calculated using three variables, namely minimum, average and maximum. \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Main Engine** & **Auxiliary Engine** \\ \hline Power & 2500 kW & 450 kW \\ Unit & 1 & 1 \\ SFOC & 183 & 213 g/kWh \\ Fuel & MFO & MFO \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Engine information. Figure 10: Retrofit cost various types of fuel vessel. The fuel consumption of a 600 TEU container vessel that uses MFO is 6296.66 tons per year based on daily SFOC multiplied by 312 days of operation. For the calculation, the yearly consumption of LNG, based on the heating value of diesel oil, is 4958.2 tons per year or 228,871.27 MMBtu. Table 5 shows yearly fuel consumption LNG and MGO. The annual pilot diesel fuel at the terminal is approximately 10% of the total MFO consumption per year or 629.67 tons [25]. The annual fuel price for LNG is 6.27 million USD compared to MFO, which is 8.13 million USD. Therefore, there is a difference of 1.86 million USD between LNG and MFO. It simply implies that the use of LNG is more economical compared to MFO. Supposing the annual OPEX is calculated yearly based on Moore Maritime Index, 2.228 million USD will be realized, meaning LNG is more economical. Based on an interview with one of the vessel owners, the economic analysis for a 10-year scheme is shown in Table 6.  
CAPEX was calculated using an approach based on a literature review, and USD 3,617,624 was realized. OPEX data were not given, and the interviewee only mentioned the profit per container, which is 10 USD. It simply implies that only 80% of the container vessel space is occupied by a total of 600 TEU. Assuming the vessel uses LNG as fuel, only 480 TEU container is conveyed on every single trip from Jakarta to Singapore.