Md. Nazmul Islam Sarkar, Anwarul Islam Sifat, Sourav Paul, Md. Shahadat Hossain, Mushfiqur Rahman,
Institute of Energy, University of Dhaka, Dhaka-1000, Bangladesh.
North South University, Dhaka-1229, Bangladesh
Email: sarkarmni@gmail.com
As Bangladesh continues to expand its renewable energy sector, reliable solar radiation data is becoming increasingly important for designing efficient solar power systems. However, measuring solar radiation requires expensive equipment and continuous maintenance, making comprehensive data collection challenging across the country. Researchers from the Institute of Energy, University of Dhaka, have proposed an innovative solution: estimating solar radiation using readily available temperature and rainfall data.
The study developed 16 empirical models to predict monthly average daily solar radiation for Dhaka using temperature differences, precipitation, and extraterrestrial solar radiation. These models were evaluated using internationally accepted statistical methods to determine their accuracy and reliability.
The results were highly encouraging. Most models achieved a coefficient of determination (R²) between 0.80 and 0.90, indicating strong agreement between estimated and measured solar radiation. Among all the models, one combining temperature variation with extraterrestrial solar radiation delivered the best performance, while models incorporating rainfall also showed excellent accuracy.
One of the study’s most significant findings is that commonly available weather data can provide reliable estimates of solar radiation, reducing the dependence on costly monitoring equipment. This approach offers a practical solution for regions where direct solar measurements are unavailable, enabling better planning for solar photovoltaic systems, renewable energy projects, and climate-related research.
Although the models were developed using data from Dhaka, the researchers suggest they can be applied across much of Bangladesh due to the country’s relatively uniform geography and climate. This makes the research particularly valuable for policymakers, engineers, investors, and researchers working to accelerate Bangladesh’s clean energy transition.
As Bangladesh moves toward a more sustainable energy future, cost-effective methods like temperature-based solar radiation estimation can play a vital role in improving project planning, reducing uncertainty, and supporting the widespread adoption of renewable energy technologies.