Study of Technical and Economic Indicators of Autonomous Energy Complexes using Renewable Energy Sources for Heat and Electricity Supply to Greenhouses

The paper presents the results of calculations of technical and economic indicators of energy complexes based on renewable energy sources for heat and power supply of greenhouses. Costs and expenditures of heat energy resources of traditionally used types and on the basis of non-traditional, renewable energy sources for heating of greenhouses located on the ground surface and in the ground at the depth of 0.6 m are determined by calculation. Based on the calculations of technical and economic indicators and climatic conditions, as well as the accumulated experience in the use of resources based on renewable energy sources in the Republic of Uzbekistan prepared the following recommendations: the cost of 1 m³ of gas obtained from a biogas plant is quite acceptable for heating greenhouses, the payback period of biogas plants is 6.6 years of use, taking into account the winter season; when using photovoltaic plants for power supply of greenhouses in comparison with the traditional distribution network, the payback period depending on the type of grown products is from 4 to 6 years; energy resources obtained from renewable energy sources are quite suitable for heating and power supply of greenhouses on the territory of Uzbekistan. The results of calculations show that in greenhouses located on the surface and in the ground, due to the difference in the coefficient of heat of combustion, the consumption of biogas is on average 1.4 times higher. At the same time, the cost of produced energy is much higher than traditional sources when switching to alternative energy sources. The combined use of various energy saving methods allows for a significant reduction in energy production costs from 20 to 40%, depending on the region in Uzbekistan. Thus, energy resources obtained from renewable energy sources are quite suitable for heating and power supply of greenhouses.