Performance Improvement of Roof Transparent Solar Still Coupled With Agriculture Greenhouse

Abstract

-In Egyptian desert, growing plants is difficult due to harsh climate (hot at the daytime and cold at the night), infertile soil, low average rainfall and lack of fresh water for irrigation purposes. A set of simple transparent solar stills are integrated with a new solar driven agriculture greenhouse (GH). The stills are placed at the GH roof to use the extra solar radiation (above that required for plant photosynthesis process) for water desalination. In addition to water desalination concept the solar still units even reduce the cooling load during the daytime. A net of aluminum metal coated with black colour is placed on the base of the solar still units to raise the water temperature (enhance desalination process) and provide partially shading for the GH. Using aluminum net decreases also the number of solar still units required to produce the required amount of GH fresh water leading to a significant cost reduction.. Therefore, this technique can be used for the application where a higher VTR is essential.The main objectives of this work are sizing of the aluminum net, spacing between solar still units to obtain the threshold of plant requirements. Also fresh water production and greenhouse climatic conditions that plant needs (temperature, relative humidity, air velocity and amount of oxygen) are simulated.Numerical simulation was carried out for the hottest day of Borg Elarab, Alexandria (Egypt).

Evaluation of different sunshine-based models for predicting global solar radiation – case study: New Borg El-Arab city, Egypt

“…values of MABE and RMSE for all models are also in the acceptable range, and best values are donated by two Robaa Models(5,6). Moreover, all models display an excellent r values which are large than 0.99.…”

“…There is a growing interest in different renewable energy resources, as well, developing new resources due to the instability of oil prices [1][2][3][4][5][6]. Some existing energy sources such as fossil fuel or nuclear power can be harmful to the human and environment.…”

Availability and Feasibility of Water Desalination as a Non-Conventional Resource for Agricultural Irrigation in the MENA Region: A Review

“…The deserts adjacent to sea water could be exploited by performing saltwater desalination in the greenhouse systems. Simple transparent solar stills could be used in new solar-powered agriculture greenhouses for water desalination [25]. The stills are fixed on the greenhouse roof surface.…”

“…The stills are fixed on the greenhouse roof surface. A certain amount of solar radiation is intercepted by the plants for the photosynthesis process and the main part is collected by the solar still units for desalination [25]. Under tropical and temperate conditions, a humidification-dehumidification (HDH) water desalination system can produce 11.6 and 20.4 m 3 /year-ha fresh water, with power consumption of 1.6 and 1.9 kWh/m 3 , respectively [22].…”

Solar Driven Agricultural Greenhouse Integrated with Desalination System; Energy-Water-Food Nexus

“…MJ/m 2 .day [46,47]. During the summer, excess solar radiation about twice the plant need is available.…”