The Open Renewable Energy Journal

2012, 5 : 7-14
Published online 2012 May 4. DOI: 10.2174/1876387101205010007
Publisher ID: TOREJ-5-7

Optimum Collector Tilt Angles For Low Latitudes

C. O.C. Oko and S. N. Nnamchi
Department of Mechanical Engineering University of Port Harcourt, PMB 5323, Port Harcourt, Nigeria.

ABSTRACT

Determination of the optimum collector tilt angles for low latitudes is the main subject of this paper. The monthly, seasonal and yearly average daily values of insolation were calculated for tilt angles ranging from 0-40o. Microsoft Excel was used to fit equations on monthly, seasonal and yearly average daily insolation with respect to tilt angles. The calculus method of optimization was employed to establish the optimum tilt angle for low latitudes, 4.86- 13.02 oN, spanning the territory of Nigeria. Expressions for the optimum tilt angles with respect to the low latitudes were also obtained. The results obtained compare favourable with those in literature and are useful for designing solar equipment in the range of the low latitudes considered in this study.

Keywords:

Solar radiation, flat-plate solar collector, optimum tilt angles, low latitudes, solar energy.