Simulation and Calculation of Parameters of a Small Solar Greenhouse in Order to Increase its Energy Efficiency

The article presents the results of research, during which using the example of the climatic conditions of the Kashkadarya region (Republic of Uzbekistan) a methodology has been developed to increase the energy efficiency of double-slope solar greenhouses. A literature analysis has shown the potential for energy savings in the greenhouse farming of the agribusiness. At the same time, it is shown that, despite the extensive research carried out in a number of countries in this area, it is necessary to continue studying the problem of putting into practice the parameters of their orientation on the terrain for various geographical regions to maximize the perceived total solar radiation. The paper presents an analysis of the research results on the dependence of the total solar radiation incidence on a gable glass-roofed greenhouse with a usable area of 50 m 2 , a wall height of 2 m and a roof slope height of 1.5 m on the design parameters of the latter and the trajectory of the sun. The simulation of the solar greenhouse operation modes was carried out in the MATLAB package, taking into account changes in the environmental parameters of the area in the period from November 15, 2023 to March 15, 2024 with a latitude of 38.87° and an orientation from 0 to 90° with an interval of 5°. As a result of the simulation, the optimal parameters of the greenhouse were determined for the above period (azimuthal angle of the surface γ opt = 45°, angle of inclination of the surface β opt = 50°) with the maximum total solar radiation for the specified period equal to ∑ I max = 35660 MJ, which exceeds by 20% the radiation for a standard-sized greenhouse. Generalization of the simulation results made it possible to develop a methodology for determining the geometric characteristics (dimensions and orientation parameters) of solar gable greenhouses with specified climatic conditions according to the criterion of maximizing the incident total solar radiation in winter, which can be extended to other regions of Uzbekistan in order to increase the energy efficiency of the agribusiness sector.