The expediency of studying the varying potential of wind and solar energy in the northern strip of the Ukrainian Carpathians is substantiated. The technique of conducting experiments to determine the natural potential of wind and solar energy is proposed and a model for determining the relative volumes of electricity generation by wind farms and solar electrical installations is developed. Based on the conducted research, according to the Drohobych meteorological station, an energy assessment of wind and solar energy resources in the northern strip of the Ukrainian Carpathians was performed. It is substantiated that the theoretical curves of distribution of wind velocity in separate quarters of the year in the territory of the northern strip of the Ukrainian Carpathians are described by the Weibull distributions. Based on the calculations, it is established that the highest total daily solar radiation is in the summer months. Daily graphs of the relative generation of electricity by wind farms and solar electric installations have been constructed. The expediency of formation of combined systems of energy supply of objects from wind and solar energy in the northern strip of the Ukrainian Carpathians has been established. The substantiated patterns of change in the natural potential of wind and solar energy, as well as the graphs of the relative generation of electricity from them, will significantly speed up managerial decisions and improve their quality.

The analysis of the development of alternative energy sources in the developed countries of the world was carried out, as well as the strategy of the implementation of wind energy in Ukraine was considered. The emphasis was on the design and operation of wind power units and the investment of investment funds in modernizing existing wind power plants and building new ones. The most attractive regions for wind power use in Ukraine was presented. The advantages and disadvantages of using nontraditional energy sources and the features of operation of wind power plants were substantiated.

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The article considers the issue of increasing the efficiency of coolers of the material heated during drying by using a heat pump unit to produce artificial cold. The scheme of use of a thermal pump in a complex with the drying installation and the portable cooler of material is offered. A mathematical description of the stationary modes of operation of the drying unit, material cooler and heat pump elements on the basis of a steam compressor refrigeration unit is formulated. At creation of physical and mathematical models of heat and mass transfer in the course of drying and cooling of material (grain) the following conditions are accepted simplifying the mathematical description, but without changing real process: moisture from the material is removed according to Dalton's evaporation law, while the moisture in the material evaporates and is removed simultaneously; moisture content and temperature in the volume of the material are evenly distributed, heat and mass transfer occurs only between the surface of the material and the drying agent; the effects of radiation and contact heat transfer are taken into account by heat transfer coefficients; stationary fields of temperature and moisture content are assumed to be one-dimensional, which vary according to the coordinate calculated in the direction of movement of the material; when cooling the moisture removal material is not taken into account for low residual moisture; the size of the surface of the material in the process of drying and cooling does not change; the heat exchange equipment of the heat pump is an object with concentrated parameters. Using the obtained mathematical dependences, graphical dependences of changes in grain and air temperature are constructed, which allow to evaluate the expediency of using a heat pump. The formulated mathematical model of stationary modes of the heat pump drying unit with artificial cooling of the dried material can be used to evaluate the feasibility and energy efficiency of the used refrigeration machines for grain cooling, especially after high-temperature processing. The obtained analytical dependences in the form of a closed system of equations can be used to optimize the parameters of the heat pump drying unit by the criterion of minimizing energy consumption.

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