| Title |
Calculation of Solar Heat Gain Orientation Factors in Accordance with Korea’s Building Energy-Saving Design Standards |
| Authors |
Jaehyun Yoo ; Sungmin Yoon ; Doosam Song |
| DOI |
https://doi.org/10.6110/KJACR.2026.38.8.435 |
| Keywords |
에너지절약설계기준; 지역별 설계 기준; 방위계수; 일사 유입 Building Energy-Saving Design Standard; Climate-based design; Orientation factor; Solar heat gain |
| Abstract |
This study introduces solar heat gain orientation factors for the four climate regions specified in the Building Energy-Saving Design Standards. An orientation factor is defined as the ratio of solar irradiance incident on a vertical plane of a given orientation to the global horizontal irradiance. We utilized hourly solar radiation data from the Meteorological Administration, selecting four representative stations: Daegwallyeong, Seoul, Busan, and Gosan. Solar altitude, azimuth, and sunrise/sunset times were calculated using each station's coordinates and timestamps. Incident irradiance on orientation-specific vertical planes was then estimated based on a standardized reference geometry. Global horizontal irradiance was broken down into beam and diffuse components using the Erbs model, which relies on the clearness index. This approach accounted for beam, diffuse, and ground-reflected radiation. Summer orientation factors were determined by averaging monthly values from June 15th to August 15th for each region. The results reveal significant seasonal and regional variations. In inland regions, the winter south-facing factor ranged from 1.12 to 1.27, but this dropped to 0.52~0.57 in summer. Conversely, the west-facing factor increased to approximately 0.71 in summer, indicating a greater impact on cooling loads. Jeju exhibited a distinct pattern influenced by its latitude. These findings offer valuable insights for designing windows and shading systems and for future improvements to solar-related coefficients in building energy standards. |