Accurate Output Forecasting Method for Various Photovoltaic Modules Considering Incident Angle and Spectral Change Owing to Atmospheric Parameters and Cloud Conditions

Abstract

Because semiconductors absorb wavelengths dependent on the light absorption coefficient, photovoltaic (PV) energy output is affected by the solar spectrum. Therefore, it is necessary to consider the solar spectrum for highly accurate PV output estimation. Bird’s model has been used as a general spectral model. However, atmospheric parameters such as aerosol optical depth and precipitable water have a constant value in the model that only applies to clear days. In this study, atmospheric parameters were extracted using the Bird’s spectrum model from the measured global spectrum and the seasonal fluctuation of atmospheric parameters was examined. We propose an overcast spectrum model and calculate the all-weather solar spectrum from clear to overcast sky through linear combination. Three types of PV modules (fixed Si, two-axis tracking Si, and fixed InGaP/GaAs/InGaAs triple-junction solar cells) were installed at the University of Miyazaki. The estimated performance ratio (PR), which takes into account incident angle and spectral variations, was consistent with the measured PR. Finally, the energy yield of various PVs installed across Japan was successfully estimated.

Measurement and Modeling of 3D Solar Irradiance for Vehicle-Integrated Photovoltaic

“…In case the high-efficiency multi-junction cells are used for VIPV, it is essential to consider the spectrum impact correctly of the cross effect between the spectrum and angular distribution of the solar irradiance [33]. For example, a detailed spectrum energy model for the tandem solar cell was developed at the University of Miyazaki and recently published [34]. The model, as mentioned above, was expanded to the design of the future high-efficiency solar cell for VIPV application in the worst-case combination of atmospheric parameters [35] and realistic atmospheric parameters and measured spectrum [36].…”

The Outdoor Field Test of the 4T III-V on Si Tandem PV Module and Its Energy Yield Modeling

“…The base model of the spectrum is Bird's model [37]. Bird's model only covers the clear sky days, and we expanded it to cover all-climate roughly [38]. This new spectrum model and the response of the tandem module was validated by the long-term (multiple years) measurement of the performance of the module [38].…”

“…The field test was done at the University of Miyazaki. The details of the measurement setup can be found in our recent publication of Applied Sciences [38], as shown in Figure 2.…”

“…The performance model we used was identical to the one we used to analyze the PV module using the 2T configuration [38]. We called it an MS2E model (Miyazaki Spectrum-to-Energy method).…”

“…First, we need to define the solar spectrum. The spectrum we assumed was a linear combination of the spectrum of the clear sky condition and that of the overcasting condition [38]. The spectrum of the overcasting condition was assumed that the solar power was lost just by absorption, corrected by the solid angle of the sky affected by the slope angle of the module.…”