A 4E Comparative Study between BIPV and BIPVT Systems in Order to Achieve Zero-Energy Building in Cold Climate

The growing demand for energy has led to the popularity of building integrated photovoltaic (BIPV) systems. However, photovoltaic (PV) system efficiency decreases as the temperature increases. To address this issue, a study was conducted on a BIPV thermal (BIPVT) system, which can generate both thermal and electrical energy, to enhance its efficiency. In this study, for the cold weather in Tabriz city in Iran, BIPV and BIPVT systems are compared with each other in terms of energy, economy, exergy, and environment (4E) and the goal is to fully supply the thermal and electrical load of the desired building. The studied criteria are electrical power and heat recovery, payback time (PBT), exergy efficiency, and saved carbon dioxide (SCD) from the energy, economic, exergy, and environmental point of view, respectively. Finally, it is concluded that in cold weather, the BIPVT system can achieve a 7.15% improvement in produced power compared to the BIPV system and 52.2% of the building's heating needs are provided. It also causes the exergy efficiency to improve by an average of 1.69% and saves 34.98 ton of carbon dioxide. The PBT of this study is calculated as 5.77 years for the BIPV system and 4.78 years for the BIPVT system.