Comparison of solar radiation models reveals key parameters for solar energy harvesting

Solar radiation is an abundant energy source. Prior to establishing solar plants, a reliable assessment of the solar resource is needed. Tahir et al. compare the performance of seven reanalysis datasets with high-quality surface measured data for Balochistan, Pakistan. Their detailed statistical study gives a very broad view of the performance of contemporary reanalysis datasets in this specific region.

The quality of reanalysis datasets for solar resource assessments depends mostly on the cloud and aerosol data that is input to the radiation schemes of the models. Here in particular the cloud input data depend heavily on complex data assimilation techniques and cloud microphysics modeling. The performance of the datasets exhibits significant seasonal variation and is highly sensitive to periodic events, like a monsoon.

“The performance of the dataset changes by changing the temporal resolution of the data used for comparison,” said author Zia ul Rehman Tahir. “The monthly mean data show better performance compared to sub-daily data, but the accuracy of the data is compromised.”

Each of the reanalysis models include different methods of data assimilation and modeling. The researchers found that aerosols are a key component to include in all models. The one model excluding aerosol performed significantly worse than the rest.

“The results of this study can provide important information regarding the planning of solar plants for regions with similar climatic conditions outside Balochistan,” Tahir said. “Further, this study will provide information to the researchers who are working in the area of solar energy assessment using satellite or reanalysis data in nearby regions.”

Source: “Evaluation of the reanalysis surface solar radiation from NCEP, ECMWF, NASA and JMA using surface observations for Balochistan, Pakistan,” by Zia ul Rehman Tahir, Muhammad Azhar, Manhal Mumtaz, Muhammad Asim, Ghulam Moeenuddin, Hanzalah Sharif, and Sohaib Hassan, Journal of Renewable and Sustainable Energy (2020). The article can be accessed at https://doi.org/10.1063/1.5135381 .