DEVELOPMENT OF A GREENHOUSE SYSTEM FOR TROPICAL LOWLAND IN INDONESIA

Wageningen UR - A&F (former IMAG) developed together with Plant Research International (PRI) and the Dutch industries Rovero Systems B.V. and Plasthill B.V. and the Indonesian company PT East West Seed Indonesia a new greenhouse system for the production of high quality horticultural products in the tropics. In this study plastic-covered greenhouses are designed which are particularly adapted to the regional circumstances of tropical lowland in Indonesia. The greenhouse design has enough resistance against local wind loads, has high natural ventilation, but is at the same time mainly closed for insects by using insect nets. The airflow and the temperatures in the greenhouse are simulated by CFD software during design stage to optimize greenhouse size, shape and the ventilation openings. A new plastic film covering is developed. The new covering consists of a 200 µm polyethylene film with a lifetime of about 3 years in Indonesia. The film contains a UV-block pigment and has highly light diffusing properties. Additionally film prototypes are developed, which selectively reflect near infrared radiation (NIR) with the objective to reach a cooling effect inside the greenhouse. Six identical greenhouse prototypes are produced in The Netherlands and built in the isle of Java in Indonesia in spring 2003. In the greenhouses tomatoes are cultivated and observed. Additionally climate measurements are carried out to evaluate the new designed greenhouses.