The importance of financial cost for renewable energy projects: economic viability assessment of renewable hybrid mini-grid systems in Indonesia

Still a lot of Indonesia's population lacks access to electricity, and a large number of those people live in remote areas or on islands. Traditionally, electrification of areas not yet connected to the main electricity grid and too remote for grid extension has mainly been achieved through installation of decentralized generation units with diesel generators. However, with decreased cost of renewable energy technologies, renewable hybrid mini-grid systems are becoming economically viable options in an ever-increasing number of places. This paper analyzes the economic viability of renewable hybrid mini-grid systems with solar Photo-Voltaic cells, batteries, and diesel generators in a typical un-electrified village in Indonesia employing local data. The analysis is conducted by utilizing HOMER simulation techniques to design the optimal renewable hybrid mini-grid systems and the economic viability assessment of the system is performed by comparing the levelized cost of energy of the system with that of the conventional diesel system under different financial scenarios. Further financial analyses, such as Internal Rate of Return and Net Present Value, are performed for the hybrid systems to investigate what kind of financial scenarios (debt/equity ratios) and public aid (international aid and government fund), would make the hybrid systems attractive to private investors. The analysis has clarified that even at the most conservative scenario with 100% equity finance, the levelized cost of energy of the renewable hybrid mini-grid system is lower than that of the diesel system. Further analysis has shown that grant finance that covers 35% of the total project cost could make the hybrid system a profitable investment project for private investors even in the most conservative scenario. The paper also demonstrates that the profitability of renewable hybrid mini-grid systems is highly affected by financial scenarios (debt/equity ratios) in comparison with that of diesel systems, concluding with policy recommendations.