# Orientation and Exposure Efficiency of a Solar Tracking Surface in Clear Sky
## 1 Introduction  
Among the known renewables, the most commonly explored and widely used is solar energy, which is energy generated from the power of the solar radiation. This is the cleanest method of energy production and the less harmful to our climate [1]. Due to its sustainability and endless resources, it can be called \"completely green energy\". Besides its clear advantages, solar energy presents some drawbacks, which are mainly due to its verynature. In different places in the world we can count on various ratios of sunny hours, and even in the hottest places in the world it is difficult to capture enough solar energy to be able to convert it to be used in technological applications. For example, it was found that most solar panels have a relatively low efficiency, which is less than 40% [2]. In order to increase the efficiency of solar panels, technologists and researchers developed the approach of solar tracking. A solar tracker is a device which ensures maximum intensity of the sun's rays at the surface of the installed solar panel over time [2]. This system, in order to increase the energy collected from direct irradiance, which is of the highest intensity, moves the photovoltaic panels to orient them perpendicular to the sun's rays. Over the years, plenty of models have been developed and an intense and continuous increase in interest in solar tracking technology is visible in the literature [3; 4; 5; 6; 7]. A team of researchers led by [PERSON] [3] claims that generating electricity using solar energy is inefficient. They carried out a project focusing on how to improve the efficiency of solar panels. The researchers found that the solar panel receives the most sunlight when it is perpendicular to the sun's rays, but that sunlight changes direction regularly with changing seasons and weather. Today, most solar panels are repaired, i.e., the solar panel has a fixed orientation to the sky and does not rotate to follow the sun. To increase the illumination of a unit area by sunlight on solar panels, they are designed to track the production of electricity by the sun. The design mechanism holds the solar panel and enables the panel to perform an approximate three-dimensional (3-D) hemispherical rotation to track the sun's movement throughout the day and improve overall electricity production. This system can achieve maximum lighting and energy concentration and lower electricity costs by requiring fewer solar panels, so it is of great importance for research and development. Another research project [4] is for a tracking app for self-tracking 3 kW solar energy off-grid, i.e., a concentrated solar energy system. This sun tracker app uses sunlight in a Stirling system or concentrated PV system by implementing a dynamic mechatronic platform and digital electronic control system to autonomously concentrate solar energy. The solar tracker uses Siemens Solar Library's Solar function block on Siemens Simatic industrial logic programmable logic TIA microcontroller platform (PLC), remotely monitored by Siemens Simatic iOS S7-1200 application for iPhone/iPad. The project meets the goal of providing a high-precision dynamic solar tracking mobile platform for a concentrated solar power system that is easy to transport, assemble and install over a rural area. Real-time experiments monitored with the Arduino PIC processor show that the implemented solar tracker project performs continuous tracking of sunlight with high optical accuracy. IoT (Internet of Things) has become a separate research field since the development of internet technology and other communication media [5]. IoT optimizes several tools such as sensor media radio frequency identification, wireless sensor networks and other smart objects that allow humans to easily interact with all devices connected to the internet network. The purpose of this research is to build an IoT-based solar cell tracker which can be controlled through mobile Apps so the data can be read anywhere as long as there is an internet network.