Regression Model for Optimum Solar Collectors’ Tilt Angles in Libya

The present study presents a regression function for optimum tilt angle for fixed mode flat-plate solar harvesters suitable for different locations in Libya, sky conditions and albedo values. The research based on 14 years -15 minutes time series solar irradiation components which provided by Solargis database platform for 24 different locations in Libya, based on the contract signed between the Solargis Company and Wadi AlShatti University. Several transposition models are applied - corresponding to each location - for estimating the tilted global solar irradiance components according to recommendation of a local recent study. The proposed model corrects the optimum tilt angle by involving the three components of the solar irradiation: direct beam, sky-diffused and ground reflected solar irradiances. The results proved the applicability and reliability of the obtained regression model. In addition, results showed the high potential of the proposed model for use in engineering design, eco-energetic analysis and optimum design processes.