A Review on Optimal Inclination Angles for Solar Arrays

Dhanesh Jain, Mahendra Lalwani


The knowledge of solar radiation falling on horizontal surface is the fundamental requirement for installing and monitoring the solar technologies. Due to variable nature of sun radiation, the power production of solar photovoltaic is fluctuating as compare to conventional power plant that’s why the cost of power is increase. During the many decades, in order to estimate the horizontal components of solar radiation on hourly, daily and monthly mean basis have been estimated by different empirical models. There is one possible solution to improve the power production cost by changing the tilt angle and orientation angle on the basis of different factors such as time, season and location. To capture the maximum solar radiation inclination angle play an important role.

The purpose of this study is to provide a review of different diffuse models proposed in past and provides the optimal tilt angle for different locations around the world on the basis of monthly, seasonally, bi-annually and  yearly.  This review would be beneficial for the further research in solar energy in term of, to identify the optimal tilt angle and collection of radiation for different location in the globe. Additionally, to get the proper accuracy and reliability of orientation angle and tilt angle to get the strong correlation with solar radiation for different time periods such as monthly, seasonally, half yearly and yearly at desired location.

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Solar Energy; Tilt angle; Solar radiation; Inclination angle; Solar Photovoltaic

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