Articles
NATURALLY VENTILATED GREENHOUSES FOR MEDITERRANEAN CLIMATES
In the case of greenhouse developments in many parts of the world including the Meditterranean Basin, a prototype solution has been the simply constructed poly tunnel as described by Baeten et al. (1985), Virhammar (1982), and Verlodt et al. (1985). Success with the tunnels has lead to significant expansion in some locations; unfortunately, more tunnels are usually built in the style of the prototype until a location becomes ineffective and inefficient.
As a greenhouse production operation is enlarged, it is highly desirable to incorporate large areas under one roof to facilitate efficient production management, effective and uniform climate control, energy efficiency, and economic use of construction materials.
Such expansion concerns can be greatly facilitated by using gutter connected structures described by Brun (1985) and von Zabeltitz (1985). The basic prototype tunnel may still be used in the form of a roof, but the entire collection of tunnels must be raised up in order to have more expanse under one roof.
Along with the desire to have low cost, simple construction, the greenhouse must be designed to satisfy the aerial climatic requirements of the crops to be grown in terms of temperature, humidity, and carbon dioxide.
It must be energy efficient and also labor efficient even in developing countries.
It must be an effective production machine within a reasonable range of climatic conditions of a given location (Short and Bauerle, 1986).