Performance assessment of an innovative exhaust air energy recovery system based on the PV/T-assisted thermal wheel

This research work aims to assess the performance of an innovative exhaust air energy recovery system consisting of a building integrated photovoltaic/thermal (BIPV/T) and a thermal wheel (TW). This BIPV/T-TW system has two main operating modes, namely winter and summer. The exhaust air is used for pre-heating and pre-cooling the ambient fresh air through a TW in the winter and summer modes of operation, respectively. Besides, the pre-heated fresh air (in the winter mode) and the heated exhaust air (in the summer mode) is used for reducing the temperature of PV panels and consequently improving their electrical efficiency. The electrical and thermal performance of the system is calculated and compared with those of the conventional BIPV/T and TW systems. Besides, a performance evaluation criterion (PEC) is defined in this study to investigate the overall performance of the studied systems. The results shows that the BIPV/T-TW system has higher PEC than the BIPV/T and TW systems. Furthermore, the effect of various important parameters on the yearly average PEC of the BIPV/T-TW system is analyzed. The economic assessment of BIPV/T-TW represents that the return time of investment according to simple payback (SP) and net present value (NPV) is a reasonable value.