3.2.1. Well to Tank Inventory Analysis

Transportation pathways of LNG and MGO fuel were determined based on literatures by Korea Gas Corporation (KOGAS), EIA and others [41]. Table 2 summarizes the information on the supply chain while Figure 5 illustrates maritime transportation routes for each case: *Case 1-LNG from Qatar* and *Case 2-LNG from USA* whereas *Case 3-MGO from Saudi Arabia* and *Case 4-MGO from USA.*

**Table 2.** Design factors for modelling the life cycle of fuels.


**Figure 5.** Ocean transport routes of LNG and MGO [42].

Table 3 presents the specification of LNG and crude oil carriers which are considered to transport the marine fuels to bunkering facilities in South Korea. The LNG carrier is considered to use a steam turbine driven by boil-off gas with 30% of efficiency. Boil-off gas is produced 0.15% of LNG cargo per day [13]. Typical types of LNG and crude oil carriers, currently engaged in the service, were selected; the cargo capacity of LNG carrier is 147,237 m<sup>3</sup> whereas crude oil carrier is 57,741 m3. Table 4 shows the detailed description of the four case studies.


**Table 3.** Specification of estimated LNG carrier and Crude oil carrier [43].


**Table 4.** Descriptions of study cases.
