Advancements and applications of transpired solar collectors: a comprehensive review of performance, design, and sustainability

Solar heating becomes more popular as energy-efficient and low-carbon building technologies grow. The air is heated by building facades with TSCs. Air heated by solar energy from a perforated metal sheet is distributed throughout the building. Despite their simple design and potential to reduce heating needs, collector design, airflow characteristics, climatic conditions, and building operating requirements affect their performance. Recent TSC technology developments in absorber and perforation configurations, airflow management, thermal performance, glazing effects, climatic effects, integration with PCMs, heat pumps, photovoltaic systems, and other building energy technologies are covered in this review. According to reviewed studies, airflow rate, draft velocity, perforation geometry, absorber characteristics, solar irradiance, ambient temperature, and building operating conditions affect solar collector performance. Summertime high solar irradiance and moderate ambient temperatures increase instantaneous thermal efficiency and exhaust air temperature, but heating-intensive climates benefit most from solar collector systems in winter and spring, when heating demand is highest. Some studies estimate annual energy savings at 55 kWh/(m²·year), but these values vary based on factors such as climate, airflow configuration, building characteristics, operating strategy, reference measurement system, and foundation area, making them not universal. Results show that solar collector systems improve facade air ventilation and energy performance in low-carbon buildings. This study synthesizes solar collector applications in building-integrated systems, unlike previous studies that evaluated discrete performance or solar air heating technologies. The review suggests research to improve large-scale implementation and decarbonization by identifying research gaps in dynamic modelling, climate-adaptive optimization, standardized perforation design, and system integration strategies.