Consideration of solar heat impact into the calculation methods of heat energy needs

The issue of energy efficiency of buildings is now relevant for Ukraine, as the vast majority of them belong to the mass construction of the twentieth century. Efficient use of thermal energy presupposes the expediency of taking into account, in addition to heat loss, also additional heat inputs, among which - solar heat inputs to the building area. In some methods, this component is not taken into account, or is taken into account quite large. A dynamic approach to the analysis of energy performance of buildings is given in the European standard EN ISO 13790, which was introduced in Ukraine in 2013, using the model 5R1C. But this method has not been widely used in Ukraine. The aim of the study was to increase the efficiency of energy management of buildings by taking into account solar heat in their area in different methods and models. The paper presents suggestions to amend the appliance of the heat load graph and math modeling for measuring energy consumption of the buildings. Amendments include forecasting that considers solar heat impact on the building. Work done based on the example of 5 floored apartment building. Authors of the paper made an analysis of the variability of climatic data using international hourly weather data for Kyiv. Comparative analysis of the three different methods of calculations of solar heat impact showed promising results: using heat load graph with consideration of solar heat impact allows to reduce the energy consumption allotted for heating by 37 % for North-South window orientation and by 28 % for West-East window orientation; using DSTU B A.2.2-12:2015 standard allows to achieve reduction by 11 % for North-South window orientation and by 9 % for West-East window orientation; using grid model 5R1C – 10 % for North-South window orientation, 8.5 % for West-East window orientation. Key words: heat energy consumption, heat load graph, dynamic model, solar heat impact