This study analyses the feasibility of the Sea floating PV (SFPV) system utilization in conjunction with Diesel generator (DG) to supply the resorts at Small Kei Island, Southeast Moluccas, Indonesia. The SFPV system uses off-grid scheme with a specific scenario that is by dividing the battery into three equal parts which are used interchangeably in order to reduce the fluctuation of the output power generated by DG at once to meet the daily load requirement for 24 hours. The impact is the battery charge cycle changed to twice in three days, thus the battery life will increase to 1.5 times longer. In this study, the economic analysis is done with the loan interest of 10% and the operating time for 25 years. With electricity tariff of 1 USD/kWh obtained the most feasible and profitable combination of capacity of DG and SFPV systems is 130 kW and 20 kW respectively. The combination yields the duration of PBP for 9 years 0 months and 9 days, NPV of 36,545 USD, IRR is 11.65%, and PI ratio is 1.016.