A combined energy–saving heat supply system was proposed that included a combined ETS unit and a ceiling fan, and provided the normative air parameters in a livestock room, with an air temperature of −17 °C and air relative humidity (ARH) of −75%. A heat supply system of a preventive maintenance premises for calves was chosen as the subject of the study. Comparative analysis of the temperature and ARH distribution with height in the preventive maintenance premises, was carried out, with and without a ceiling fan. The study showed that, during the heating period, application of the ceiling fans helped to raise the air temperature and to reduce ARH, in the areas where young stock is located, in accordance with the normative indicators. The energy-saving effect was achieved by supplying warmer ventilation air, which accumulated in the upper zone of the premises from the ceiling fan to the locations of the animals. At the same time, there was a decrease in the consumption of electric energy for the heat supply system of up to 14%.

The article considers the calculation of the main design parameters of a geothermal air cooling system in livestock premises, which, unlike traditional systems, do not use fossil fuels to generate heat. They simply take energy from the soil, while, as a rule, electricity is used only for the operation of fans, compressors and pumps. The purpose of the study is to reduce energy consumption when creating the technologically necessary temperature and humidity conditions in premises by using the cold of the earth’s strata. The calculation of the heat exchanger installed inside the livestock premises is reduced to the choice of design and energy parameters of the surface heat exchanger of the cooling unit, as well as to the determination of the flow rate of water passing through the heat exchanger. Water cooling is done in a heat exchanger buried vertically in the soil (the so-called probe). The probe is a plastic pipe lowered into the well and filled with a special filling with good thermal conductivity. The article presents the calculation of the probe length, since this parameter of the heat exchanger-probe is the main parameter of the installation.

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The use of air heat curtains allows you to limit the amount of cold air incoming the room through open gates or doors, as well as to heat it up. The article considers the influence of air heat curtains on the energy balance of livestock premises. The calculation method is presented and the main aerodynamic characteristics of an air curtain installed in a calf house for 50 animals are substantiated. The main heat and power and structural parameters of the air curtain have been determined. On the basis of the heat balance of the calf barn, its modes of operation are substantiated. It has been established that the power consumption for the fan drive during the operation of the air curtain is significantly less than the cost of thermal energy to compensate for the air temperature in the room from the inflow of cold air. The technical and economic calculation showed the effectiveness of the use of air heat curtains in microclimate systems for various livestock facilities of agricultural production.

Calculated and experimental studies of thermal processes and the efficiency of heat storage of solid thermal storage materials in an electric thermal storage (ETS) were carried out. Changes in the thermo physical properties of selected thermal storage materials depending on temperature are analyzed. The specific heat storage capacity in the temperature range from 50 °C to 650 °C of such materials as magnesite, chamotte, dinas, corundum was estimated. The research was carried out on an electric thermal storage with an electric power of 2.4 kW with heat storage elements made of magnesite. The temperature distribution is obtained in the heat storage element, as well as in the wall of the air channels of the heat storage elements. Measurements of the temperature of the heated air in the channels of heat storage elements and at the exit from the ETS were carried out. Temperature measurements were carried out with chromel-alumel thermocouples in a ceramic shell and chromel-kopel in a heat-resistant fabric cover. As a result of experimental studies, the temperature distribution in the heat storage elements of ETS is obtained. Based on these data it was calculated the amount of stored heat by heat storage elements of ETS for the complete cycle of its operation.