A MILP-Based Framework for Renewable Energy Curtailment Mitigation in High-Renewable Island Grids

As renewable energy penetration increases, renewable energy curtailment has become a critical challenge in power systems with high shares of solar and wind generation. This study develops a mixed-integer linear programming (MILP) model for the day-ahead scheduling of battery energy storage systems (ESS) to minimize renewable energy curtailment on Jeju Island, South Korea. Simulation results based on 2024 operational data show that ESS effectively reduces curtailment by shifting surplus renewable energy over time; however, its benefits diminish as storage capacity increases because additional charging is no longer possible once the ESS reaches its capacity limit. Under a scenario in which renewable energy capacity doubles relative to 2024 levels, large-scale ESS deployment alone could not eliminate seasonal curtailment. In contrast, integrating ESS with a 15% increase in electricity demand substantially reduced curtailment, highlighting the critical role of demand growth in absorbing surplus renewable generation. These findings demonstrate that battery storage alone is insufficient for high-renewable island power systems. Instead, an integrated flexibility strategy combining ESS with demand-side management, sector coupling (e.g., Power-to-Gas), and enhanced transmission interconnections is required to maximize renewable energy utilization while maintaining system reliability.