Fogging system is an essential equipment in the greenhouse industry.
The major advantage of the high pressure fogging is to flash evaporating billions of tiny water particles (at around 70-120 bars – water drops of 5 to 20 micron size droplets) then the air is cooled and humidified. It is more efficient than a low-pressure fogging to decrease the temperature inside the greenhouse.
On average, a 10% increase in relative humidity creates a 2 to 3 degree Celsius drop in temperature.
Moreover, using a high-pressure pump, the water sent to the spray nozzles spreads creates a mist layer in the air. This system helps to reduce significantly dripping or wetting compared to low-pressure fogging. The size of the droplet is important because water will not stay on the plants. Indeed, it can promote fungus attacks and plant damages.
High pressure fogging benefits
Below a synthesis of the high- pressure fogging option benefits:
- Micro drop-let flash evaporation
- Cool and humidify the inside environment
- Create an uniform climate across the greenhouse
- Improve plants physiological condition
- Increase production (yield)
- Reduce energy and water (irrigation) costs
- Reduce CO2 losses
- Odor neutralization, dust suppression…
- Can be controlled by a climate computer through sensors
- Cost effective solution
One of the disadvantages of high pressure misting (other than its cost) is nozzle clogging. For example, calcium deposits can accumulate inside of the pipe and nozzles reducing flow.
Ultrasonic humidifier system could solve this problem. The concept is to use atomized plate which generates 1.7MHz ultrasonic wave. Under the action of ultrasonic high-frequency oscillation, the water is changed into particles of 5 to 10 μm. Then, the cool air is blow out by a fan to the growing area.
Note: it will be important to ask you greenhouse manufacturer about the equipment load resistance (kg/m2 or lb/ft2) before adding a high-pressure fogging option