Desalination and Greenhouses

Abstract

Egypt’s hot climate, high solar radiation, and lack of irrigating water are limiting factors for successful farmland, and makes growing crops an expensive and resource-intensive endeavor. In addition, Egypt is composed of 95% desert land which makes growing plants in open fields difficult due to infertile soil, low average rainfall, and lack of freshwater for irrigation purposes. These difficulties can be overcome by using Greenhouses (GHs) for agricultural purposes which can provide the proper environment for plants growth in all seasons. GHs are a type of indoor facility which is enclosed by transparent covers and have the ability to control internal climatic conditions and could potentially reduce the amount of water required for irrigation purposes in agricultural production. In addition, the use of GHs allows the production of high quantity and quality crops throughout the year. In cold climate regions, GHs have been introduced to collect (trap) solar energy and heat the GHs in order to maximize crops productivity. However, in arid areas with high atmospheric temperatures and high solar intensity, this can be a burden on plants growth and reducing the temperature inside the GHs would be essential for successful plants growth. On the other hand, desalination has been introduced as an alternative nonconventional water resource for regions of limited freshwater resources. Extensive desalination technologies have been launched in the Middle East and North African (MENA) region since the 1970s. It is sometimes less expensive to desalinate saline water than to transport treated water from remote freshwater resources (300–500 km away). In Egypt, desalination is considered as a strategic alternative to water transport particularly after the construction of Ethiopian dam on the Blue Nile (the main source of water for Egypt). Integration of desalination with GHs has recently been introduced in warm and hot climate regions as an alternative solution for food production particularly in remote areas as in desert and coastal zones. This chapter outlines the desalination processes as a nonconventional resource for both potable and GH irrigation water. In addition, a summary of the different types of agricultural GHs is described. This is followed by a presentation of the different options of integrating desalination processes as a source of water for GHs irrigation. Finally, the chapter concludes with some case studies required for optimizing GH–desalination integrated system’s operational performance.