Assessment of light environmental impacts from offshore wind farms in South Korea

Offshore wind farms are expanding rapidly as a clean energy solution but raise concerns about light-related environmental impacts, such as shadow flicker and light pollution, affecting ecosystems and human communities. This study assesses the light environmental impacts of offshore wind farms in South Korea, specifically evaluating daytime shadow flicker and nighttime light pollution, and proposes mitigation strategies tailored to diverse landscape contexts. Using advanced geospatial tools, including QGIS and WindPRO, light-related disturbances were analyzed across three representative sites: Aphae (rural), Jangbogo (island), and Dadaepo (urban). Shadow flicker exposure was quantified based on turbine specifications, solar dynamics, and observer locations, while light pollution from aviation obstruction lights was assessed through spatial luminance analysis. The Aphae site exhibited the highest shadow flicker exposure, with up to 154 days annually and 79 h per year in some regions, while Dadaepo's urban zone displayed moderate impacts, particularly in tourist areas like Molundae Observatory. Jangbogo experienced negligible effects due to natural buffering and greater separation distances. Light pollution intensity correlated with proximity and turbine visibility, with 8-13 turbines visible in highly impacted zones. Tailored mitigation strategies, such as optimized turbine placement, green buffers, zoning regulations, and habitat preservation, are essential to minimizing adverse impacts. This research underscores the need for location-sensitive planning to achieve sustainable offshore wind energy development while safeguarding ecological and human well-being.