In few cases, greenhouses may require cooling systems. This occurs when the daily average temperature is too high for the crops to function properly. In this case, cooling the greenhouse is the only way to keep the crops inside healthy and productive. Cooling a greenhouse is more expensive than heating a greenhouse. An investment in a cooling system must therefore be a well considered decision. The preferred cooling method for a greenhouse is through evaporative cooling. Evaporative cooling is the process of having particles of water evaporate, which leads to a drop in temperature through increased humidity. There are two systems that use this principle in commercial greenhouses: high pressure fogging and the Pad & Fan cooling system. In recent years, semi-closed greenhouses have been developed based on the same principles as the Pad & Fan system.
Humidity Control: Dehumidification & Humidification
Humidity control in greenhouses
The importance of humidity control in greenhouses
Challenges in Humidity Control
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Consistency in Humidity Levels: Maintaining uniform levels of humidity is challenging, but essential to avert microclimates within the greenhouse.
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Transpiration & Dehumidification: Effective humidity control in greenhouses is fundamental for optimal transpiration in plants and ensuring the right amount of moisture evaporation from leaves.
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Condensation Management: Controlling condensation through dehumidification in greenhouses is critical to prevent the formation of breeding grounds for diseases and mildew.
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Balancing External & Internal Influences: Adjustments and continuous monitoring are crucial in balancing both internal and external environments, creating a stable, conducive climate for plant growth.
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Custom-Tailored Solutions: Due to varying global climates and differing local conditions, humidity control and dehumidification solutions must be customized to fit individual needs and resources.
Do you want to know more about dehumidification or high pressure fogging?
Do you want to know more about dehumidification or high pressure fogging?
Technology for Dehumidification in Greenhouses
A range of innovative methods and technologies, including fans, vents, wet walls, shade cloths, radiant heating, and fogging, are available for ensuring optimal humidity control in greenhouses.
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Horizontal & Vertical Fans for Dehumidification: Utilizing Horizontal Airflow (HAF) and Vertical Fans that take dryer air from above the screen are crucial for achieving consistent air movement and effective humidity mitigation, thereby eliminating detrimental microclimates.
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Ventilation windows Incorporating advanced venting solutions with real-time weather monitoring stations is essential for regulating airflow and maintaining a conducive environment within greenhouses.
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Screening for Humidity Management: Screening fabrics play a significant role in regulated solar exposure and addressing excessive humidity, ensuring plant protection and energy conservation.
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Radiant Heating: This method provides effective heating solutions, especially for vine crops, allowing precise temperature control and adjustment of the ambient heat around the plants.
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Fogging Systems: Implementing appropriate fogging systems is vital for not only lowering the temperature but also increasing humidity without causing damage to the crops, and is particularly beneficial for plants that thrive in more humid environments.
- Mechanical Cooling: Mechanical cooling methods such as the HortiCooler system, allow for the most precise control by condensing humid air and capturing the condensate water. For crops that are sensitive to high humidity such as roses and cannabis, the relative humidity is even used to as primary climate control setpoint.
