Title: Determination of optimal tilt angles in some selected cities of Nigeria for maximum extractable solar energy

Authors: T.R. Ayodele; A.S.O. Ogunjuyigbe; S. Oladeji

Addresses: Power, Energy, Machine and Drive Research Group, Department of Electrical and Electronic Engineering, Faculty of Technology, University of Ibadan, Ibadan, Nigeria ' Power, Energy, Machine and Drive Research Group, Department of Electrical and Electronic Engineering, Faculty of Technology, University of Ibadan, Ibadan, Nigeria ' Power, Energy, Machine and Drive Research Group, Department of Electrical and Electronic Engineering, Faculty of Technology, University of Ibadan, Ibadan, Nigeria

Abstract: In this paper, optimum tilt angles are determined for some selected cities for optimal performance of solar panels. The study also compares the effects of placing solar panel on optimum tilt angle to that of horizontal position in terms of extractable solar power as well as the cost of energy. Regression equations relating optimum tilt angle to the declination angle are developed for the selected locations and the accuracy is tested using coefficient of determination (R2). Some of the key results reveal that optimum tilt angle changes between 0° and 42° throughout the year in Nigeria. The optimum value is found to be 0° during the raining seasons (i.e., April-August) in all locations. The findings also show that the optimum tilt angle increases in the range of 5° to 42° during the dry seasons (September-March) reaching its maximum value in the month of December in all the locations. The extractable power on optimum inclined surface increase in the range of 2.5%-9% compared to horizontal surface while the cost of electricity (COE) reduces by 6%-9% when solar panel is placed on optimally inclined surface.

Keywords: global solar radiation; optimum tilt angle; solar panel; angle of declination; Nigeria.

DOI: 10.1504/IJRET.2018.095800

International Journal of Renewable Energy Technology, 2018 Vol.9 No.4, pp.453 - 483

Received: 28 Nov 2017
Accepted: 07 May 2018

Published online: 11 Oct 2018 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article