국내 태양광 발전-ESS의 용량 크레딧 분석

This study applied the ELCC (Effective Load Carrying Capability) and EFC (Equivalent Firm Capacity) methods to assess the capacity credit (CC) of domestic solar power and energy storage systems (ESS) more precisely and comprehensively. ELCC measures the additional load a power source can support while maintaining system reliability. EFC represents the capacity of an energy source in terms of an equivalent firm power source, ensuring the same level of system adequacy. The ELCC and EFC of each year's solar power-ESS combination were calculated and analyzed, considering their unique annual capacity factor characteristics. The comparative analysis provided insights into the impact of ESS expansion on capacity credit. The results demonstrated that integrating solar power with ESS significantly enhances grid stability. In particular, ESS expansion increased both ELCC and EFC values, mitigating the variability of solar power. These findings highlight the role of ESS in maintaining a reliable power supply as renewable energy penetration grows. This study is significant as the first attempt to calculate the EFC of both conventional and renewable energy sources in the domestic power system. The results suggest that EFC can serve as a valuable reference for evaluating energy sources in power system planning and operational strategy development.