Modeling the influence of cloudiness on diffuse horizon-tal irradiation under various sky conditions in Nigeria

  • Authors

    • Samuel Nwokolo University of Calabar
    • Julie Ogbulezie University of Calabar
    2017-10-10
    https://doi.org/10.14419/ijpr.v5i2.8312
  • Equatorial Line, Diffuse Fraction, Clearness Index, Diffuse Horizontal Irradiation, Sky Conditions
  • In this study, modeling the influence of cloudiness on diffuse horizontal irradiation (DHI) in six tropical ecological zones in Nigeria (Latitude 4.75-13.067oN and Longitude 3.333-13.16oE) using 22-year data (July 1983- June 2005) was analysed for all sky and clear sky conditions. The result revealed that the absorption of DHI in the global horizontal irradiation (GHI) portion of the solar spectrum is greatly enhanced in the Southern tropical zones as a result of heavy presence of smog, cloudiness, and high water vapour parameters such as relative humidity, dew point temperature and precipitable water thereby increasing the diffuse fraction in the zone. However, in the Northern tropical zones, the absorption of DHI in the GHI portion of the solar spectrum lowered due to presence of low smog, cloudiness and low water vapour parameters thereby reducing the diffuse fraction in the region. The quadratic regression correlation model developed deeming from the model performance test indicates that the proposed model could be used to estimate DHI accurately over the six tropical ecological zones in Nigeria and other locations with comparable sky condition to Nigeria.

  • References

    1. [1] McCree, K.J. (1972). Test of current definitions of photosynthetically active radiation against leaf photosynthesis data. Agric. For. Meteorol. 10, 443–453. https://doi.org/10.1016/0002-1571(72)90045-3.

      [2] Wang, Q., Kakubari Y., Kubota M. (2007). Variation of PAR to global solar radiation ratios along altitude gradient in Naeba Mountain. Theo. and Appl. Clima., 87, 239-253 https://doi.org/10.1007/s00704-005-0220-6.

      [3] El-Sebaii, A.A., Al-Agel F. (2012). Estimation of horizontal diffuse solar radiation from common meteorological parameters: a case study for Jeddah, Saudi Arabia, International Journal of Ambient Energy, 1 – 8.

      [4] Bhattacharya, A.B, Kar, S.K., Bhattacharya, R. (1996). Diffuse solar radiation and associated meteorological parameters in India, Ann. Geophysi., 14, 1051-1059. https://doi.org/10.1007/s005850050366.

      [5] Page, J.K. (1960). The estimation of monthly mean values of daily total short-wave radiation on vertical and inclined surfaces from sunshine records for latitude 40oN and 40oS. Proceedings UN Conferenceon New Sources of Energy, 1961, Rome, Italy, United Nations, 4, 598: 378-390.

      [6] Iqbal M. (1980). Prediction of hourly diffuse solar radiation from measured hourly global radiation on a horizontal surface. Solar Energ. 24, 491-503. https://doi.org/10.1016/0038-092X(80)90317-5.

      [7] Jacovides C.P. Boland, J., Asimakopoulos, D.S. (2010). Comparing diffuse radiation models with one predictor for partitioning incident PAR radiation into its diffuse component in the Eastern Mediterranean basin, Renew. Energy, 35, 1820-1827. https://doi.org/10.1016/j.renene.2009.11.015.

      [8] Liu, B.V.H. Jordan, R.C. (1979). The interrelationship and characteristics distribution of direct, diffuse and total solar radiation, Solar Radiation, 22, 87-90.

      [9] Mohammed A.A.A. (2010). The anaylsis of the characteristics of the solar radiation climate of the daily global radiation and diffuse radiation in Amman, Jordan, International Journal of Renewable Energy, 5, 23-38.

      [10] Theophile, L., Rene, T. (2013). Estimation of diffuse solar radiation in area between 5oN and 10oN of Cameroun, Natural Resources, 4, 279-285 https://doi.org/10.4236/nr.2013.43035.

      [11] Basharat, J. & Abid T.S. (2017). Generalized models for estimation of diffuse solar radiation based on clearness index and sunshine duration in India: Applicability under different climate zones. Journal of Atmospheric and Solar-Terrestrial Physics, 157: 16-34.

      [12] Martinez-Lozano, J.A., Utrillas M.P., Gomez, V. (1994). Estimation of the diffuse irradiation from global solar irradiation. Daily and monthly average daily values. Renewable Energy, 4: 95-100 https://doi.org/10.1016/0960-1481(94)90069-8.

      [13] Nfaoui, H. Buret, J. (1993). Estimation of daily and monthly direct, diffuse and global solar radiation in Rabat (Morocco). Renewable Energy, 3: 923-930 https://doi.org/10.1016/0960-1481(93)90052-I.

      [14] Jain, P.C. (1990). Model for diffuse and global irradiation on horizontal surfaces. Solar Energy, 45: 301-308 https://doi.org/10.1016/0038-092X(90)90015-5.

      [15] Ibrahim, S.M.A. (1985). Diffuse solar radiation in Cairo, Egypt. Energy Conversion and Management, 25: 69-72 https://doi.org/10.1016/0196-8904(85)90072-X.

      [16] Erbs, D.G., Klein, S.A. Duffie, J.A. (1982). Estimation of the diffuse radiation fraction for hourly, daily and monthly average global radiation. Solar Energy, 28: 293-302 https://doi.org/10.1016/0038-092X(82)90302-4.

      [17] Nwokolo, S.C. (2017). A comprehensive review of empirical models for estimating global solar radiation in Africa. Renewable and Sustainable Energy Reviews, 78: 955–995 https://doi.org/10.1016/j.rser.2017.04.101.

      [18] Nwokolo, S.C., & Ogbulezie, J.C., (2017a). A Quantitative Review and Classification of Empirical Models for Predicting Global Solar Radiation in West Africa. Beni-Suef University Journal of Basic and Applied Sciences, (In Press).

      [19] Nwokolo, S.C., & Ogbulezie, J.C. (2017b). A single hybrid parameter-based model for calibrating Hargreaves-Samani coefficient in Nigeria. International Journal of Physical Research, 5(2): 49-59 https://doi.org/10.14419/ijpr.v5i2.8042.

      [20] Willmott, C.J. (1981). On the validation of models. J. Phys. And Geogr. 2, 184-194.

      [21] Burari, F.W. (2004). Correlation of global and diffuse solar radiation components with meteorological parameters for Bauchi, Jolorn, 5(1): 49-55.

      [22] Nwokolo, S.C., Ogbulezie, J.C., Toge, C.K., John-Jaja, S.A. (2016). Modeling the influence of relative humidity on photosynthetically active radiation from global horizontal irradiation in six tropical ecological zones in Nigeria. New York Science Journal, 9(11): 40-55.

      [23] Ituen, E.E., Esen, N.U., Nwokolo, S.C., Udo, E.G. (2012). Prediction of global solar radiation using relative humidity, maximum temperature and sunshine hours in Uyo, in the Niger Delta Region, Nigeria. Advances in Applied Science Research, 4, 1923-1937.

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    Nwokolo, S., & Ogbulezie, J. (2017). Modeling the influence of cloudiness on diffuse horizon-tal irradiation under various sky conditions in Nigeria. International Journal of Physical Research, 5(2), 91-100. https://doi.org/10.14419/ijpr.v5i2.8312