Design of the Heat Pipe Helium Greenhouse for the Effective Use of the Soil Heat

This scientific work presents the results of scientific research on the use and accumulation of solar energy for heat supply of a solar greenhouse. For a real assessment of the problem, the following information can be cited as an example: in a greenhouse with a total area of 234 m2 covered with polyethylene film must be installed, on the average, with 6-8 furnaces to provide a certain amount of warm air. One furnace consumes about 2448 m3/h of natural gas for four months, and during this time 8.6 kg of carbon dioxide (CO2) is emitted from one furnace. As a result, taking into account the payment for the consumption of natural gas, the problem of the cost of the obtained products, energy conservation, and also environmental protection is very urgent. To solve this problem, a solar greenhouse with an additional heating chamber was constructed at the research site of the State Energy Institute of Turkmenistan. In this structure, excess of solar and heat energy of the soil was accumulated in mountain stones, and carbon dioxide that emits soil (horse manure was used as a soil) was used to feed the Chlorella vulgaris suspension grown in the photobioreactor, which in its turn had a beneficial effect on its cultivation. To transfer heated air from the additional heating chamber to the solar greenhouse and the accumulated thermal energy of the soil, polyethylene pipes with holes were used. Due to the use of the heat capacity of the materials (rock stones), a two-layer coating of the structure, compaction of the northern side with wool and accumulated heat energy, it was possible to achieve a positive temperature in the solar greenhouse in the minus environmental values. The technologies and processes considered in this research are mainly renewable energies and technical (chemical reactions) solutions such as photovoltaic (PV) modules, phase exchange material (PCM), underground heat storage technologies, energy efficient heat pumps and facade materials for the better heat insulation. The obtained results of the research work can be applied in solar greenhouses, the construction of which is planned in the areas remote from the central power supply network, since heat supply is carried out using solar energy and electric lighting is implemented due to the solar panels with a built-in LED lamp. It should be borne in mind that the intensity of solar radiation on the territory of Turkmenistan fluctuates in the range of 700-800 W/m2, which indicates the huge possibilities of using solar energy.