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2026 Vol.14, Issue 2
Performance Comparison Between Glass-to-Glass and Glass-to-Steel Modules on BIPV Structures
Ji Woo Sohn1
,
Hongjun Jang1
,
Dongchul Suh2
,
Sungho Hwang3*
,
Young-Su Kim4*
1KU-KIST Green School, Korea University, Seoul, 02841, Korea
2Department of Chemical Engineering, Hoseo University, Asan, 33100, Korea
3Research Institute for Energy Technology, Korea University, Seoul, 02841, Korea
4Research Institute of Industrial Science and Technology (RIST), Pohang, 37673, Korea
*Corresponding Author
30 June 2026. pp. 49-55
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Abstract

This study presents an outdoor performance comparison of glass-to-glass (G2G) and glass-to-steel (G2S) single-cell mini-modules designed for building-integrated photovoltaic (BIPV) applications. The modules were installed vertically facing south on a building rooftop in Seoul, South Korea, and their irradiance, operating temperature, electrical parameters, and energy yield were evaluated under summer climate conditions. The G2S modules consistently operated at lower temperatures than the G2G modules due to the enhanced heat dissipation provided by the steel rear structure. As a result, the G2S configuration exhibited a higher open-circuit voltage, while the G2G modules showed higher short-circuit current, primarily due to optical and irradiance-related effects under vertical installation. This trade-off led to a time-dependent performance behavior: the G2G modules produced higher energy yield before 13:00, whereas the G2S modules outperformed the G2G modules during the afternoon under elevated temperature conditions. When integrated over the entire measurement period, the difference in cumulative energy yield between the two configurations was only 0.07%, which falls within the experimental uncertainty and indicates that their overall energy yields are effectively equivalent. These results demonstrate that although G2G and G2S modules deliver similar total energy output, their performance characteristics differ depending on irradiance and temperature conditions. Consequently, glass-to-steel module configurations may offer practical advan͒tages in hot climates or applications where thermal management is critical, highlighting the importance of climate- and time-dependent considerations in BIPV module design.

Keywords
Building Integrated Photovoltaics
Glass to glass module
Glass to steel module
Energy yield
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 14
  • No :2
  • Pages :49-55
  • Received Date : 2025-12-24
  • Revised Date : 2026-01-07
  • Accepted Date : 2026-01-07
  • DOI :https://doi.org/10.21218/CPR.2026.14.2.049
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