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Vol. 4 (2017)

Solar Azimuth Angle in the Tropical Zone

September 12, 2017


Basing on the concept of sun position, appropriate relationships for determining the solar azimuth angle were derived. The derived formulas were compared with those available in literature and proposed to determine the solar azimuth angle all over the year and all over world. Some comments were given on some of them. Here it was found that the formulation of Braun and Mitchell [1], recommended by Duffie and Beckman [2] in their respectful book could not be applied in the tropical zone. The calculated results using the derived formulas were compared with the available results in literature.


  1. Braun, J.E. and Michell, J.C. (1983). Solar geometry for fixed and tracking surfaces. Solar Energy, 31(5), 439-444. doi:10.1016/0038-092X(83)90046-4
  2. Duffie, J.A. and Beckman, W.A. (1991). Solar engineering of thermal processes (2nd ed.). New York, NY: Wiley & Sons.
  3. McCormack, J. (2004). Surveying, 5th Edition, John Wiley and Sons, New York.
  4. ASHREA Handbook. (2009). Fundamentals. In: Climatic Design Information. American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta. (Chapter 14).
  5. Tregenza, P. and Sharples, S. (1993). Daylight Algorithms. Report ETSU. University of Sheffield.
  6. Iqbal, M., 1983. An Introduction to Solar Radiation. Academic Press, New York.
  7. Kittler, R. and Darula, S. (2013). Determination of time and sun position system. Solar Energy, 93, 72-79.
  8. Muneer, T. (1997). Solar Radiation and Daylight Models for the Energy Efficient Design of Buildings. Architectural Press, Oxford.
  9. Buckner, R. (1984). Astronomic and Grid Azimuth. Landmark Enterprises, Rancho Cordova.
  10. Ali, A.T. (2012). An error modeling framework for the Sun azimuth obtained at a location with the hour angle method. Positioning, 3, 21-29.
  11. Blanc, PH. and Wald, L. (2012). The SG2 algorithm for a fast and accurate computation of the position of the sun for multidecadal time period. Solar Energy, 86 (10), 3072–3083.
  12. Sproul, A.B. (2007). Derivation of the solar geometric relationships using vector analysis. Renewable Energy, 32, 1187–1205. doi:10.1016/j.renene.2006.05.001
  13. Duffie, J.A. and Beckman, W.A. (2013). Solar engineering of thermal processes (3rd ed.). New York, NY: Wiley & Sons. DOI: 10.1002/9781118671603.app1