Three tips of greenhouse humidity control

August 26,2021

Humidity is one of the significant challenges that impact plant growth. A healthy and dry environment is a primary method to defect the bacterias and fungi. Especially during the sunset, the temperature plummets compare to the daytime. In addition, when the plants radiate on the cold glazing, both of them will gradually reach the dew point in the cold night. Therefore, temperature and humidity can cause wetness issues in the greenhouse.

Three methods can help you work off the humidity by using ventilation, condensation, and desiccant dehumidification, respectively.

Using ventilation is a traditional way to remove humidity, but people can't control it precisely. And this is high consumption of energy method. Once the temperature in the greenhouse is heated to a certain degree, the air can contain more humidity. In addition, when the inside of the greenhouse temperature and humidity reach the upper limit, the air exchange with cool outside air will process through the vent and exhaust fans. The cool outside air will heat itself to maintain inside constant temperature when entering the greenhouse. A study found that plants will increase the transpiration when the heat conveys to the beneath of the foliage. And the result also shows that about 40% of energy will be utilized to transpire the vapor by plants. Therefore, the escalating relationship between heating, ventilation, and transpiration limits the dehumidification of the ventilation.

Conventional refrigerant and compressor air conditioning are adopted condensation technology. The air containing moisture is absorbed on the cold refrigerant coil, where the water condensate due to the low temperature. Then the water is drained. During the process, the soil and dust form an ideal place for bacteria and mold growth because of the saturated condition inside the greenhouse. Therefore, the distribution of the air system can freely transform the bacteria and mold to any unit, which can bring a significant challenge to the condensation method. In addition, high energy consumption is also the drawback of this method.

Desiccant dehumidification is using a chemical adsorbent dehumidifier to absorb water in the air. The moisture air through the absorbent and be dried, then be released into the environment. In addition, compared to the ventilation method, this approach has been found to reduce 60% energy consumption because the desiccant material can be regenerated by heating it. What's more, the heat that can regenerate the desiccant can keep the greenhouse warm. Moreover, compared to condensation, this method is less consumption of energy. The main flaw of the desiccant is the high initial cost.

In a word, you can choose any of these three methods to remove the humidity of the greenhouse, but we highly recommended using a dehumidifier. If you have any questions about the dehumidifier, please feel free to contact us!