Методика розрахунку несучої здатності сонячних панелей як елемента забезпечення енергоефективності будівель

Abstract

Extensive use of solar panels for providing low-rise buildings with electricity has led to the development of methods for assessing the load-bearing capacity of solar panels, taking into account the size of the panel, the angle of inclination to the horizon and climatic loads in a given geographical area. The solar panels are calculated as plates hinged along the contour. Self-weight loads of the panel, snow, wind and ice loads are determined according to DBN B.1.2-2: 2006 "Loads and impacts" and are reduced to a component that is normal to the plane of the panel. Working formulas were obtained for determining the extreme and operational design values of loads, checking the strength and deflection of panels, as well as the maximum allowable spans according to the criteria of strength and structural rigidity. An example of calculation of solar panels placed at angles of inclination to the horizon from 15° to 75° on the roof of a building in Kropyvnytskyi were performed. Strength checks should be performed on combinations of panel self-weight, snow and maximum wind pressure. Deflection check at small angles of panels inclination is carried out taking into account the same combination of loads, and at big angles of inclination - taking into account only ice load. In all cases, the condition of rigidity is decisive. Permissible span L (smaller size) of a solar panel with 3 mm tempered glass sheathing in the conditions of Kropyvnytskyi varies from 0.68 m to 1.36 m. It increases as the angle of inclination increases and as the B/L ratio approaches to 1. The allowable span varies by 13…16% with length ratio of the larger side of solar panel to the smaller one in the range from 1.4 to 2.0. This allows to take the values of the allowable span, corresponding to the ratio of the parties B/L=2.0 in order to simplify the safety margin. The obtained working formulas and their implementation in the form of a calculation sheet in Microsoft Excel allows to perform similar calculations for other source data. Further research focuses on the establishment of allowable spans of solar panels of typical design in the conditions of each of the regions of Ukraine.