EVALUATION OF TWO COOLING SYSTEMS IN PARRAL TYPE GREENHOUSES WITH PEPPER CROPS: LOW PRESSURE FOG SYSTEM VERSES WHITENING

In the Mediterranean region, the high temperature and low humidity of the air inside the greenhouse during the summer, has traditionally being tackled by whitening the cover to reduce the energy input.
In low cost “parral” type greenhouses, alternative systems have started to be incorporated, like low pressure fog systems.
This work compares the operation of two cooling systems inside such greenhouses and their effects on the internal climate and production of a pepper crop.
Two treatments namely, low pressure fog system to keep a maximum water vapour pressure deficit of 1.5 kPa and normal whitening were tested in two “parral” type greenhouses with a different treatment in each.
Significant differences in temperature occurred in the early stages of the crop with the temperature being 8ºC higher under the whitened cover than with the fog system.
The water consumption in the fog system during the whole cycle was 219 L/m² and no significant differences were found in the commercial production of pepper.

International Symposium on Greenhouse Cooling

D. Meca, J.C. Lopez, J.C. Gazquez, E. Baeza, J. Pérez-Parra, G. Zaragoza

Parral-greenhouse, refrigeration systems

https://doi.org/10.17660/ActaHortic.2006.719.59