Energy and exergy analysis and performance optimization of buildings integrated with transpired solar collectors and phase change materials

Transpired solar collectors (TSCs) are one of the cost-effective air heating technologies that can be easily installed on building facades to provide heated fresh air to condition indoor space. The economics of TSCs can be further enhanced by integrating with phase change materials (PCMs). This study presents the performance investigation and optimization of a building-integrated TSC and PCM system (TSC-PCM). The interactions between PCM thermal properties, their locations in the building envelope, and TSC design parameters were investigated. Based on the modeling of the TSC-PCM by using energy balance and enhanced enthalpy method, a series of orthogonal tests, which varied PCM type, thickness, and location within building envelopes, and TSC suction flow rate were conducted. Multivariate testing, through the Taguchi method, was then applied to identify the optimal design combination. The results showed that the suction flow rate of the TSC-PCM on the external wall showed the highest influence on enhancing indoor thermal performance (up to 77.6 %), followed by PCM location on the external wall (up to 9.2 %). The optimized TSC-PCM system improved the thermal comfort increase index (TCI) to 3.7 and achieved a maximum thermal efficiency of 401.8 %, with an exergy improvement of 26.9 % in comparison with the use of the TSC-only. The optimized TSC-PCM system increased the average indoor room temperature to 18.8 °C, which was 6.8 % and 18.2 % higher than the use of the TSC-only and a baseline without using PCM and TSC, respectively. • Transpired solar collector and phase change material were used for space conditioning. • Energy and exergy performance of the integrated system was investigated. • The performance of the integrated system was optimized. • Appropriate design and operation can result in increased indoor thermal comfort.