Systematic review of solar air collector technologies: Performance evaluation, structure design and application analysis

• DOI: 10.1016/j.seta.2022.102885
• Publication Date: 2022-11-18T12:28:38Z
• Authors: Ji Zhang; Tingting Zhu
• Keywords: UT-Hybrid-D; 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; 7. Clean energy

A solar air collector (SAC) is a main device of a solar-thermal air system, which can absorb solar radiation and transfer the absorbed thermal energy to the air. This paper presents a systematic review of three basic types of SAC, namely, the flat-plate SAC (FPSAC), the evacuated tube SAC (EVTSAC), and the concentrated SAC. High efficiency, low heat loss and simple structure have always been the goals of SACs development and research. Enhancement methods applied in the SACs, including enhanced-surface technology, absorber materials, airflow reorganization, internal heat transfer component and integrated systems of energy storage and PV/T, are reviewed. Performance comparisons among the different SACs of each type are conducted. The analysis indicates that the FPSACs, with the groove absorber and half conical, enable a performance evaluation criterion of about 2. An evacuated tube SAC with micro-heat pipe arrays can provide a thermal efficiency up to 73 %. Among the concentrated SACs, the linear concentrating SAC with an open Brayton cycle can achieve a highest outlettemperature of 350 ◦C, corresponding to 75% thermal efficiency. It is recommended to consider the use of high-efficiency heat transfer component in the optimal design of SACs. Some suggestions for future research are proposed.