Optimal tilt angle for PV modules considering the uncertainty of temperature and solar radiation

This paper presents the hybrid differential evolution (HDE) in determining the tilt angle for photovoltaic (PV) modules. First, a Taguchi experiment was used to perform an efficient experimental design and analyze the robustness of the tilt angles for fixed south-facing PV modules. Following, the results from the Taguchi experiment were used as the initial data. Finally, the HDE method was applied to obtain a robust tilt angle setting of the tilt angle of PV modules with continuous variables. The objective is to maximize the electrical energy of the modules. In this study, three Taiwanese areas were selected for analysis. However, since temperature and solar radiation are fluctuating conditions in Taiwan, this paper presents the concepts of expectation and standard deviation to shows the probability distributions. The position of the sun at any time and location was predicted by the mathematical procedure of Julian dating; then, the solar irradiation was obtained at each site under a clear sky. To confirm the computer simulation results, experimental system are conducted for determining the optimal tilt angle of the modules. Finally, the results show that the seasonal optimum angle is 26.4° for February-March-April; -9.42° for May-June-July, 21.30° for August-September-October and 48.11° from November-December-January in the Taiwan area.