Climatic Characteristics and Complementarity of Solar and Wind Energy in Korea: Potential Benefits of Hybrid Power Generation for Mitigating Energy Droughts

Abstract

With the growing adoption of renewable energy sources, it has become increasingly important to address the risks of solar and wind energy droughts. This study examines the spatiotemporal characteristics of solar and wind energy resources across six administrative districts in Korea, using 63 years of hourly reanalysis data at a 25 km resolution. The results show that solar energy resources, despite having lower overall availability compared to offshore wind energy resources, experience fewer energy drought days and have a more uniform distribution across inland regions. Conversely, the offshore wind energy resources offer higher availability but exhibit greater regional diversity and more frequent energy drought events. While both resources show small interannual variability, they exhibit significant seasonal fluctuations, with availability varying by a factor of two to three depending on the season and region. Notably, solar and offshore wind energies complement each other seasonally, contributing to enhanced daily availability in summer and improved intra-day stability in winter. This complementarity reduces the frequency of energy droughts in hybrid energy systems that combine both resources. This result highlights the potential benefits of solar-wind hybrid power plants？integrating distributed solar systems with offshore wind farms？to improve both resource availability and supply stability.