###### Abstract  
The objects of this research are double-sided stationary vertical photovoltaic modules (PV-modules) with an \"East-West\"-oriented solar panel. The tilt angles of the Sun's rays on PV-modules at a latitude of 50\({}^{\circ}\) were determined, and the installation efficiencies of both double-sided stationary vertical PV-modules with an \"East-West\" oriented panel and PV-modules installed at an angle of latitude with a \"South\" oriented panel were compared. The horizontal azimuth of the fall of the Sun's rays during the day when using PV-modules with an \"East-West\"-oriented panel reaches a minimum at noon. The vertical azimuth of the Sun's rays remains constant throughout the day and can vary from 66.55\({}^{\circ}\) to 113.45\({}^{\circ}\). The weighted average daily installation efficiency of PV-modules with an \"East-West\"-oriented panel has the same value as that of PV-modules with a \"South\"-oriented panel, and can vary between 45.87 and 50% on different days. However, these installation options have a \"mirror\" value of the cosines of the Sun's rays falling on the surface of the PV-modules and can have values from 0.917 to 1. The results can be used as a basis for evaluating the efficiency of double-sided vertical stationary solar PV-modules with an \"East-West\"-oriented panel. PV-module; \"East-West\"-oriented solar panel; module installation efficiency; double-sided vertical PV-module; \"South\"-oriented solar panel +
Footnote †: journal: Applied sciences  
0000-0002-0001-865X/0000-0002-00  
also increasingly being used, although there are barriers to their wider uptake [2; 3]. This is due to the geographical distribution of solar energy and its high availability during the year--from 4.8 to 6.0 kWh/m\({}^{2}\)[4]. If at the end of 2018, the total capacity of the PVS was 515 GW (world capacity data), then at the end of 2023 it will have reached a value of 1400 GW [5], continuing to grow to the present time. The use of PVSs has several advantages in various sectors of the economy. In particular, they are easy to install and maintain, do not create noise, are equipped with automatic control and monitoring systems, and work both in autonomous mode and as a part of a network [6]. However, the widespread application of PVSs is difficult due to the variable intensity of solar radiation (depending on the day, season, climatic conditions, etc.) and the limited time of sunlight absorption during sunrise and sunset [4; 6]. In order to overcome these difficulties, it is necessary to develop innovative technologies and appropriate designs of the PV-modules, which will allow them to function as efficiently as possible in the given climatic conditions and ensure the maximum production of electricity with minimal capital investments [7]. Although significant progress has been made in recent years in the development of technologies and equipment for converting solar energy into electricity [8], the conventional efficiency of solar cells, as well as of the entire PV module, remains at a low level. The conventional efficiency of industrial solar cells barely exceeds the 25% threshold. For example, the ISC Constance has produced solar cells with efficiencies above 21% using only industrially proven equipment [9]. More advanced solar cell architectures include the so-called passivated emitter and rear cell (PERC), heterojunction (HTJ) and interdigitated back contacted (IBC) solar cells. The leader in the production of IBC c-Si solar cells is SunPower Corporation, which has achieved 25.15% cell efficiency on 121 cm\({}^{2}\)[10]. According to commercial PV-module manufacturers such as AIKO and Trina Solar, the maximum conversion efficiency of IBC solar cells is near 24.1% and 24.4%, respectively [11; 12]. In the case of the joint development pursued by Trina Solar and Australian National University, the IBC solar cells were at a small scale (2 \(\times\) 2 cm\({}^{2}\)) [12].