TECHNO-ECONOMIC STUDY OF PV INTEGRATION INTO A GAS ENGINE-BASED POWER SYSTEM CONSIDERING CURTAILMENT IMPACT: A CASE STUDY OF THE ALOR POWER SYSTEM

Abstract

The Solar PV capacity addition target in the 2025–2034 Electricity Supply Business Plan (RUPTL) is set at 17.1 GW. The Alor Power System has one of the highest solar irradiation potentials, reaching approximately 6 kWh/m²/day; however, no grid-connected photovoltaic (PV) plant has yet been deployed in the system. This study investigates the technical and economic feasibility of integrating Solar PV into the existing gas engine-based power system by utilizing the former constrained power plant site in Alor. The evaluation considers three PV penetration scenarios 15%, 20%, and 30% of daily energy demand simulated using HOMER Pro and integrated with the existing 10 MW gas engine power plant (GEPP). Unlike previous studies, this research contributes by evaluating the interaction between PV penetration, curtailment losses, and system-level LCOE to determine an economically optimal renewable penetration limit for an isolated gas-engine-dominated grid. The simulation results indicate that higher PV penetration reduces fuel consumption and operational costs of the gas engine plant but leads to significant daytime curtailment. Among the evaluated scenarios, 20% PV penetration yields the lowest LCOE at IDR 3,334/kWh, outperforming both the 15% and 30% scenarios as well as the GEPP-only base case (IDR 3,435/kWh). The findings demonstrate that a hybrid system configuration with 20% PV penetration and a 10 MW gas engine plant provides the most optimal LCOE for the Alor Power System. This configuration is therefore considered technically and economically feasible to support the national PV capacity expansion target of 17.1 GW under the 2025–2034 RUPTL.