Air temperature and relative humidity distribution in different type of greenhouse constructions

Abstract

Greenhouse plant production is one of the most intensive parts of the agricultural production. In order to reduce the costs and save the energy, various greenhouse constructions and different coverings are offered to the farmers. One of the biggest problems is in winter production when additional heating and light are needed as well as in summer when intensive cooling is needed. During these period construction and coverings fully show their qualities. The aim of this research was to investigate the temperature and air relative humidity distribution in the different greenhouse constructions in the different production systems in order to see if the choice of the greenhouse construction can improve the production conditions inside the greenhouse enabling the better energy efficiency and lower energy input for heating / cooling. Results show that temperature pattern and its values during the night and day depends on the greenhouse construction, plant specie that is grown and production season. Temperature differences of 6.91 degrees C in the tunnel construction during winter were found to be very significant while in the gutter-connected greenhouse these differences were not significant. In the summer period temperature differences were not significant in neither of the greenhouses. In the winter production gutter-connected greenhouse had significantly, 5.09 degrees C, higher temperatures compared to the outside during the day and during the night. In the tunnel greenhouse these temperatures were significantly higher only during the day. Air relative humidity showed significantly higher values for the summer and winter period. In the gutter-connected greenhouse these differences were higher only in the summer period.