GREENHOUSE COOLING DURING WARM PERIODS

Reducing temperatures in one of the main problems facing greenhouse management in warm climates.
Four factors which permit temperature reduction are discussed: ventilation or air renewal, crop evapotranspiration, shading and water evaporation inside the greenhouse (fog system, cooling system, etc.).

This paper includes some results of the cooling tests carried out in Mediterranean greenhouses and the calculations of a simulation programme which combines different cooling methods.
It is shown that the effect of shading is clearly more positive in badly ventilated greenhouses.
In greenhouses without fog and without crop shading greatly reduces temperature, but when other sources of cooling exist (crop transpiration, fog system or high ventilation rates), shading has little effect on greenhouse air temperature.
Curves showing the relationships of humidifying systems with ventilation rate, open air conditions and their effect on greenhouse temperature are included.

III International Symposium on Protected Cultivation in Mild Winter Climates

J.I. Montero, A. Antón

https://doi.org/10.17660/ActaHortic.1994.357.5