Scarcity of water, major critical concern in arid areas, has led to the use of low–quality irrigation water in agriculture in most of arid climate areas. The quality of water used for agriculture has to be reduced to a sustainable level that is also adapted to the environment. This paper presents the performance of a pilot condensation irrigation (CI) solar system in Tunisia under arid climate conditions. The objective of this study was to investigate the potential of this combined solar system for producing fresh water as an alternative source for irrigation in the greenhouse used for tomato growth. The preliminary testing of the CI system performance showed that moisture amounts in the buried pipes remain high for the sunny and cloudy days and dew condensation is processing mainly at night and early morning times. The produced fresh water satisfies about 15% the maximum crop water requirements during the growth period where tomato crops are most sensitive to water deficit. Based on experimental results, recommendations for system improvements design are suggested.
Keywords: subsurface irrigation, system design, solar desalination, evapo–condensation, performance evaluation, solar energy, solar power, arid climates, condensation irrigation, fresh water, greenhouses, tomato growth, water scarcity