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2026 Vol.46, Issue 3 Preview Page
High-Resolution Performance and Sensitivity Analysis of Bifacial PV by Tilt and Azimuth to Complement ECO2 Resolution Limitations

ECO2 해상도 한계 보완을 위한 양면형 PV의 설치각･방위 고해상도 성능 및 민감도 분석

Junyoung Lee1
,
Dongsu Kim2*
,
Jongho Yoon3
,
Jaewon Kim4
,
Ruda Lee4
,
Hansol Lim5
,
Kihyung Yu6
이 준영1
,
김 동수2*
,
윤 종호3
,
김 재원4
,
이 루다4
,
임 한솔5
,
유 기형6
1Master’s Program, Department of Architectural Engineering, Hanbat National University
2Associate Professor, Department of Architectural Engineering, Hanbat National University
3Professor, Department of Architectural Engineering, Hanbat National University
4Researcher, Department of Architectural Engineering, Hanbat National University
5Assistant Professor, Department of Building Systems Engineering, Hanbat National University
6Research Fellow, Department of Building Energy Research, Korea Institute of Civil Engineering and Building Technology
1국립한밭대학교 건축공학과, 석사과정
2국립한밭대학교 건축공학과, 부교수
3국립한밭대학교 건축공학과, 교수
4국립한밭대학교 건축공학과, 연구원
5국립한밭대학교 건축설비시스템공학과, 조교수
6한국건설기술연구원 건축에너지연구본부, 연구위원
*Corresponding Author
30 June 2026. pp. 47-61
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Abstract

Bifacial photovoltaic (PV) systems have garnered considerable attention for building and urban applications. However, ECO2, the Korean evaluation tool for building energy performance, currently supports only conventional monofacial PV and does not provide a dedicated model for bifacial PV. This limitation is critical as bifacial PV performance depends not only on module tilt and azimuth but also on rear-side irradiance conditions governed by ground albedo and array geometry. In this study, the annual energy yield of bifacial PV systems was quantified under Korean climatic conditions, and region-specific design guidelines were provided based on sensitivity analyses of orientation, albedo, and array configuration. Annual energy production was simulated for 16 representative cities in Korea using pvlib and TMYx weather data derived from observations between 2009 and 2023. Tilt and azimuth were varied from 0° to 90° and 0° to 360°, respectively, at intervals of 5° under albedo conditions of 0.2 and 0.8. For multi-row layouts, module clearance height was varied from 0 m to 3 m at 1 m intervals, and ground coverage ratio (GCR) was varied from 0.4 to 0.8. Increasing albedo from 0.2 to 0.8 increased annual energy production in all cities, with an average gain of 368.33 kWh. The optimal tilt shifted from approximately 30° to 25°, whereas the optimal azimuth remained near south-facing orientations. The benefits of increasing clearance height became marginal beyond approximately 1 m, whereas increasing GCR consistently reduced front- and rear-side irradiance. Overall, these results provide high-resolution reference criteria for bifacial PV design under Korean climatic and urban conditions.

Keywords
Bifacial photovoltaic
Tilt angle
Azimuth angle
Albedo
Ground Coverage Ratio, GCR
Simulation
키워드
양면형 태양광
설치각
방위각
지표면 반사율
지상피복률
시뮬레이션
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Information
  • Publisher :Korean Solar Energy Society
  • Publisher(Ko) :한국태양에너지학회
  • Journal Title :Journal of the Korean Solar Energy Society
  • Journal Title(Ko) :한국태양에너지학회 논문집
  • Volume : 46
  • No :3
  • Pages :47-61
  • Received Date : 2026-03-26
  • Revised Date : 2026-04-20
  • Accepted Date : 2026-04-22
  • DOI :https://doi.org/10.7836/kses.2026.46.3.047
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