Natural ventilation and microclimatic performance of a large-scale banana greenhouse

Natural ventilation performance is one of the key parameters for climate co ntrol in large scale, Canarian type of greenhouses which are rapidly expand ing along the Atlantic coast in Morocco. The climatic conditions were measu red and analysed in a I ha Canarian type of greenhouse, with a mature banan a crop which was the second most widespread crop under protected cultivatio n in the region of Rabat, Morocco. A global energy balance of the greenhous e is deduced, allowing for the determination of ventilation flux. New venti lation functions for very large-scale greenhouses are presented and compare d with other existing functions. The greenhouse ventilation performances are compared with those of other gr eenhouse types and discussed with respect to the improvement of greenhouse design, the use of insect-proof nets and irrigation control. (C) 2001 Silso e Research Institute.