Greenhouse Heating Solution

Geothermal temperature also has a significant impact on crop growth. Generally, the optimum geothermal temperature is in the range of 15 to 20 °C, with the lowest geothermal temperature being 13 °C and the highest geothermal temperature being 25 °C. When the temperature is above 30℃, the generation of root hairs is suppressed and the respiration of the roots becomes vigorous, so the consumption of assimilation products increases. In addition, when the ground temperature is low, the elongation and activity of roots decreases, and the activity of soil microorganisms is suppressed, resulting in poor absorption of nutrients and water. Photosynthesis of crops is affected by temperature, light intensity, and carbon dioxide concentration. It can be seen that photosynthesis greatly increases when the temperature rises, and decreases when the temperature rises above a certain temperature. When looking at the temperature at which the rate of photosynthesis reaches the maximum, the optimum temperature for photosynthesis varies by crop, with tomatoes at 20°C, cucumbers at 25°C, and green peppers at 20-25°C. It is a general trend that crops with a high temperature for photosynthesis have a high temperature for growth. Up to a certain temperature, the amount of photosynthesis increases as the temperature increases, but above a certain temperature, the amount of photosynthesis decreases. As a result of most studies, it is reported that crop growth is better when the nighttime temperature is lower than the daytime temperature. For this reason, it is advantageous to save energy and produce high-quality plants by closely examining the growth characteristics of crops and managing the change in temperature by day and night.

The earth’s temperature is rising day by day as the imbalance of the global environment due to the reckless use of fossil fuels becomes serious. Due to the imposition of carbon tax in developed countries, the use of fossil fuels is on the decline, and it is developing into greenhouse heating using alternative energy. The heat storage system using sunlight that is intense during the day stores the solar energy that enters the greenhouse during the day with sufficient heat to be used as heating heat at night on the floor of the greenhouse and the steel structure. In order to increase the amount of heat storage, in the case of hydroponics or bench cultivation in which a structure is installed on the ground and cultivated above, a water tank that can trap water is installed on the floor to store heat, and night heating is possible with only the amount of heat stored. Also, the gravel heat storage method is It is also useful to lay a certain amount of gravel on the floor of the greenhouse to store heat. A more active method is to bury the pipe at regular intervals under the floor when designing a greenhouse, circulate the high-temperature, high-humidity air in the greenhouse during the week to the pipe buried in the ground. The air in the greenhouse during the day can be maintained at the optimum temperature and humidity, and at night, it can be heated using the heat from the ground. At this time, the pipe to be buried underground is a perforated pipe with a hole in it, and by using a corrugated pipe strong against earth pressure, the heat transfer area between the air and the heat storage material can be enlarged. Design not to exceed 500mm. The heat storage material around the pipe uses gravel to increase the amount of heat storage by varying the size of gravel so that air flows smoothly.