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This article analyzes the operation of a solar energy system installed in a higher education institution, consisting of four photovoltaic stations connected to the electrical grid for self-consumption, and a solar hot water system with collectors and a storage tank. The operation of the system was modeled using the RETScreen, T*SOL, and PV*SOL software programs, based on averaged climate data obtained from the "Zhuliany" weather station. The solar system is installed on the south-facing roof of the building and consists of 262 monocrystalline silicon photovoltaic modules of Trina Solar TSM-DE08M (II) type with a power of 370 W, installed at an angle of 30° to the horizon, and 8 Veissmann Vitosol 300-T SP3 vacuum tube collectors with a power of 1.3 kW installed at an angle of 35°. The placement of the solar elements was determined through modeling, considering their dimensions, the features of the roof structure, the placement of ventilation systems, and the shading of the roof surfaces by other elements of the building in Kyiv. As a result of energy modeling, it was determined that the amount of thermal energy obtained is 6.823 MWh/year, and the amount of electrical energy is -109.16 MWh/year, with a total inverter capacity of 95 kW, a traditional fuel replacement coefficient of 50% for the photovoltaic system and 75% for the solar system with collectors, payback periods of 4.3 years for the photovoltaic system, and 13 years for the hot water system when replacing electric boilers and 16 years when obtaining hot water from a district heating network. The reduction in harmful emissions is 45 tons/year of CO2, which is equivalent to 104.3 barrels of crude oil or 19,279 liters of high-octane gasoline or 15.5 tons of recycled waste. Based on the analysis of the data, it is recommended to install such systems in higher education budget institutions to reduce electricity or natural gas consumption and reduce harmful emissions into the environment.

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This article analyses the actual, normative monthly and typical detailed climatic data for the city of Kyiv. Data on actual outdoor air temperatures during 2014-2021 were compared with indicators in accordance with Ukrainian regulations and the most common typical hourly climate files used for building energy modeling: International Weather for Energy Calculations (IWEC), Meteonorm, Typical Meteorological Year (TMY) from PVGIS tool and Onebuilding web-site. The values for outside air temperatures were compared on an average monthly basis and using the number of hours of outside air temperature duration. The latter approach allows to more accurately assess the energy efficiency indicators and energy consumption of heat supply systems with heat pumps. As the buildings energy need and energy consumption for heating values are significantly affected by heat gains due to solar radiation, a comparison of the normative value of global radiation on the horizontal surface with the values from the most common typical climatic data was also performed based on an average monthly basis. Taking into account the set of analysed climatic factors using monthly indicators for outside air temperatures and number of hours of outside air temperature duration, it is decided to use Meteonorm hourly data for Kyiv for further dynamic energy modeling of building with heat supply system based on different types of heat pumps, including the air-to-water and water(brine)-to-water ones. Also, climatic data used in RETScreen program show similar figures as normative values and therefore this program will be used for further technical and economic analysis as well and the results will be compared to the specialised program for heat pumps calculations GeoT*SOL, which also provides the detailed calculation of heat pumps system technical performance and economic calculations. In addition, possible deviations in the values of energy need for heating of the building when using different climatic data were estimated using the DesignBuilder / EnergyPlus software product. The potential deviation of energy need for heating results can be around -10…+6.5%.