# Solar Potential in Saudi Arabia for Flat-Plate Surfaces of Varying Tilt Tracking the Sun
[2] investigated the mode (ii) dynamic systems receiving solar energy on fixed-tilt flat-plate solar panels that rotate on a vertical single-axis structure and track the sun continuously. This work is a continuation of the previous two as it investigates the mode (iii) dynamic systems for the solar energy received by flat-plate solar systems with continuously variable tilt angle of the inclined surface and mounted on 2-axis sun trackers across the country. Static solar systems are widely used nowadays in solar energy production throughout the world because of their simple construction and low maintenance cost; therefore, they have received major attention from researchers (i.e., for estimating the solar potential or solar availability) at a certain location or region, e.g., [3; 4; 5]. A second preference has been given to dynamic mode (ii) solar systems because of their relatively higher performance in terms of the solar energy received, e.g., [6]. The dynamic mode (iii) solar systems have started being used in the last 20 years or so because of their higher performance in comparison to that of the other two types, e.g., [7; 8]. Much effort has been invested in improving both the moving and electronic parts for the sun-tracking sensors [9; 10]. Nevertheless, despite the technology development, the performance of such systems must be evaluated against solar radiation measurements at first hand. However, the scarcity of solar radiation measuring stations around the world has triggered studies to use solar radiation modelling, e.g., [11; 12; 13], in order to derive the optimum tilt angle and orientation for obtaining maximum solar energy on flat-plate solar panels. Other methods use a combination of ground-based solar data and modelling, e.g., [14], or utilise solar data from international data bases, e.g., [15; 16]. Recently, a new method was presented by [17] for Greece and was applied in two recent studies for Saudi Arabia [1; 2]. The proposed method [17] is able to find the maximum solar energy received by flat-plate solar systems with southward (northward) orientation in the northern (southern) hemisphere. The idea behind this methodology is applied in the present study for solar modules continuously tracking the sun. Some studies similar to the present work have already been conducted for Saudi Arabia. [PERSON] et al. [4] computed the global, direct, and diffuse solar radiation components on horizontal and tilted surfaces at Jeddah. [PERSON] et al. [15] estimated the optimal tilt angle for maximum energy reception by PV installations at 7 sites in the country. They suggested that the PV panels should be adjusted six times in a year for maximum performance, a conclusion that triggers extra installation and maintenance costs because of the moving parts involved. [PERSON] et al. [18] performed solar radiation measurements at 30 stations in Saudi Arabia in the period October 2013-September 2014 (1 year) to assess the solar potential at these sites. The World Bank [19] has derived a Global Solar Atlas, which includes Saudi Arabia. This solar map provides the distribution of the three solar radiation components over the country and is based on calculations during the periods 1994, 1999, and 2007-2018. Finally, [PERSON] et al. [20] has provided a study about the economics of solar energy in Saudi Arabia. From the above, it is clear that no attempt has been made thus far to construct a solar map for Saudi Arabia to show the solar potential on inclined flat-plate surfaces that continuously track the sun. This gap is bridged in the present study and includes two innovations. (i) For the first time, solar maps for Saudi Arabia showing maximum energy on inclined flat-plate surfaces tracking the sun are derived. (ii) The notion of the (ground-albedo) correction factor introduced in [1; 2] is also used. The structure of the paper is as follows.