A uniform climate through air recirculation under the gutters
Besides the sun there are several other sources that influence the temperature inside the greenhouse, for instance grow lights and heating pipes. Heat rises naturally, this effect is also called convection. Cold and hot air do not mix easily and therefore differences in the climate will occur. The solution for this problem is air movement and this can be achieved by air movement like for example air recirculation. Air recirculation under the gutter allows for better distribution of the air and thus a more uniform climate throughout the greenhouse.
Fungi due to poor evaporation of the crop
A poor moisture balance often results in fungi problems. Fungi grows best under high relative humidity circumstances. Air movement enable the plant to evaporate more and to transport the resulting moisture. This makes sure that fungi have less chance of damaging the crop.
Better CO2 adsorption by air recirculation under the gutter
When there is no air movement around the crop, the CO2 concentration close to the leaves of the crop will drop. This is because the CO2 is absorbed by the crop and the supply of CO2 is limited. Air recirculation under the gutter makes sure that the air is in motion and will increase the supply of CO2 to the leaves.
Air circulation allows for better control of humidity
The relatively hot and dry air transported to the crop can decrease the relative humidity around the crop. This is because hot air can adsorb more moisture than cold air. Because the humidity in the greenhouse can be controlled better, the greenhouse vents may remain closed longer. This will result in a higher CO2 level in the greenhouse.
Energy savings through a lower minimum pipe temperature
To activate the crop and control humidity usually a minimum pipe temperature is required. The rising air out of the air distribution hoses takes over this part. An advantage of this is that the minimum pipe temperature can be decreased. This saves on the energy bills!