Document Type : Original Article


1 Department of Physics and Solar Energy, Bowen University, Iwo, Osun State, Nigeria.

2 Department of Computer and Information Technology, Bowen University, Iwo, Osun State, Nigeria.

3 Department of Mathematics and Statistics, Bowen University, Iwo, Osun State, Nigeria.


Global solar radiation is the sum total of all radiation reaching the earth surface i.e. it includes: the direct and the diffused solar radiation reaching the earth surface. The instrument used for measuring this very important component arriving from the whole hemisphere is the pyranometer. This is one of the most important parameter for applications, developments and researches related to alternative source of clean and renewable energy. In cases where these data are not available, it is very common to use computational models to estimate the missing data, which are based mainly on the search for relationships between weather variables, such as temperature, humidity, precipitation, cloud cover and sunshine hours, among others.
In this research work, the baseline data for mean monthly global solar radiation and sunshine hours for three (3) geopolitical zones of Nigeria (sub-sahara regions of Nigeria) with Sokoto (North-western Nigeria) (12.910N, 5.200E), Maiduguri (North-eastern Nigeria) (11.850N, 13.080E) and Ilorin (North- Central Nigeria) (8.430N, 4.500E) were obtained from the Nigeria Metrological Agency (NIMET), Nigeria which spread from 1996 to 2010.
A linear regression correlation model was developed and clearness index estimated for each station in this study. The result shows the Angstrom coefficients and for estimating global solar radiation for zone respectively, using the Angstrom-Prescott model. The average global solar radiation for these stations was estimated, results subjected to statistical tests proven to be good estimates.
The study concluded that the Angstrom- Prescott model plays a significant role in predicting and estimating solar energy potentials in these regions


Main Subjects

[1] Mojarrad, F., Fathnia, A., & Rajaee, S. (2015). The Estimation of Receiving Solar Radiation at Earth’s Surface in Kermanshah Province. Arid Regions Geography Studies, 5(19).
[2] Ibrahim, H. (2015). Estimation of Global Solar Radiation using Sunshine- based and Temperature-based Models; case study of Adama Town. Haramaya University.
[3] Rezrazi, A., Hanini, S., & Laidi, M. (2013). Estimation ofsolar radiation with Artificial Neural Networks: analysis and synthesis of published works. In Conférence Internationale des Energies Renouvelables (CIEAR’13) (Vol. 2). Retrieved from’13-IJSET/ID_170.
[4] Ndilemeni C. C. (2013). Evaluation of Clearness Index of Sokoto Using Estimated Global Solar Radiation. IOSR Journal Of Environmental Science, Toxicology And Food Technology (IOSR-JESTFT), 5(3), 51–54. Retrieved from
[5] Innocent, A. J., Jacob, O. E., Chibuzo, G. C., James, I., & Odeh, D. O. (2015). Estimation of Global Solar Radiation in Gusau , Nigeria. International Journal of Research in Engineering & Technology, 3(2), 27–32.
[6] Gana, N. N., & Akpootu, D. O. (2013). Angstrom Type Empirical Correlation for Estimating Global Solar Radiation in North-Eastern Nigeria. The International Journal Of Engineering And Science (IJES), 2(11), 58–78.
[7] Garba, A. A., Amusat, R. O., & Ngadda, Y. H. (2016). Estimation of Global Solar Radiation Using Sunshine-Based Model in Maiduguri, North East, Nigeria. Applied Research Journal, 2(1), 19–26. Retrieved from
[8] Musa, B., Zangina, U., & Aminu, M. (2012). Estimation of Global Solar Radiation in Maiduguri, Nigeria Using Angstrom Model. ARPN Journal of Engineering and Applied Sciences, 7(12), 1623–1627.
[9] Olayinka, S. (2011). Estimation of global and diffuse solar radiations for se- lected cities in Nigeria. International Journal of Energy and Environmental Engineering, 2(3), 13–33.
[10] Yusuf, A. (2017). Characterization of sky conditions using clearness index and relative sunshine duration for Iseyin, Nigeria. International Journal of Physical Sciences Reseach, 1(1), 53–60.
[11] Adeniji, N. O. (2018). Determination of Angstroms canstants for the Estimation of global solar radiation for energy utilization in Nigeria. Bowen University.
[12] Gana, N. N., Rai, J. K., & Momoh, M. (2014). Angstrom Constants for Estimating Solar Radiation in Sokoto, North-Western, Nigeria. International Journal of Scientific & Engineering Research, 5(1), 1636–1647.
[13] Adenji, N., Akinpelu, J., Adeniji, J., & Adeola, S. (2019). Estimation of Global Solar Radiation , Sunshine Hour Distribution and Clearness Index in Three Geopolitical Regions of Southern. Jordan Journal of Earth and Enviromental Sciences, 10(2), 97–104.