چكيده به لاتين
One of the most widespread renewable energy technologies is the use of photovoltaic systems that convert sunlight into usable electrical energy. As a result of increasing panel temperature, its electrical efficiency decreases, so methods for cooling these panels must be used. Considering that the technical-economic optimization of thermal photovoltaic system has not been done in recent studies, multi-objective optimization is done in this research. For this purpose, a detailed energy analysis has been performed to calculate thermal and electrical parameters such as solar cell temperature, output fluid temperature, photovoltaic efficiency, and thermal efficiency of different schematics. In the first step, the performance of thermal photovoltaic solar collectors with three different configurations, including a water channel at the top, a water channel at the bottom of the PV panel, or both (two water channels) in three different weather conditions, are investigated. Another goal of this study is to increase water-based photovoltaic thermal panels' electrical and thermal efficiency using phase change material in different configurations. The investigation of different configurations of the photovoltaic system has not been done in previous studies and it is another innovation of this research. The sensitivity analysis is done to find the most influencing parameters on the performance, and the effects of different parameters, such as water mass flow rate and PCM thickness, on the system performance are investigated. The results show that in cases without PCM, PV/T with two water channels has the best performance in terms of electrical efficiency. The photovoltaic efficiency of this model varies between 10.71 and 11.28 percent. It was also found that the position of the phase change material layer significantly affects the collector's performance. Placing the PCM layer under the water channel shows better results in reducing the PV temperature compared to placing it above the water channel in the PV/T model with two water channels. Comparing the PV/T cases with PCM with the PV/T cases without PCM shows that adding a PCM layer to the PV/T with a water channel on top has the greatest effect, decreasing the solar cell temperature by 7.18℃. To improve the heat transfer coefficient of PCM, nanoparticles are added to it. Finally, the multi-objective optimization of the PV/T system is done by selecting multiple objective functions such as photovoltaic efficiency, thermal efficiency, and system lifetime cost. The optimal range of the objective functions in the Pareto front, have been obtained. The results of multi-objective optimization showed the optimal values of photovoltaic efficiency and thermal efficiency of concentrating thermal photovoltaic thermal system, 11.05%, and 78.14%, respectively.
