Colored Building‐Integrated Photovoltaic/Thermal (BIPV/T) Roof Systems: Experimental Testing and Modelling Insights

This paper investigates the design and performance of an air‐based building‐integrated photovoltaic/thermal (BIPV/T) system for sloped roof applications using colored PV modules. Two colors (terracotta and gray) are evaluated through experimental testing under controlled laboratory conditions to assess the impact of surface color on system behavior. Mechanical ventilation effectively reduced PV temperature by up to 13°C (1.49 m/s channel air velocity), with terracotta modules exhibiting slightly higher temperatures mainly due to color reflectance differences. Thermal efficiencies ranged between 13.9–28.6% for the terracotta and 12.5–27.3% for the gray prototype. While the proposed system achieved thermal efficiencies comparable to those reported in previous studies, commonly used convective heat transfer correlations failed to capture the behavior of the system accurately. A new empirical correlation tailored to the examined setup is introduced. This work contributes to the advancement of knowledge on colored BIPV/T systems by demonstrating that colored PV modules integrated into mechanically ventilated roof assemblies can support significant heat recovery while providing architectural design flexibility. By enabling both electricity generation and thermal recovery, colored BIPV/T systems enhance the energy efficiency and perceived economic value of solar‐integrated building envelopes, supporting sustainable building design and low‐carbon construction practices.