الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
The greenhouse techniques are considered among the most important solutions to overcome the problems of the availability of vegetables in the markets to meet local consumption at different times of the timing of the production of vegetables in the traditional way, as well as the intensification of agriculture. Due to the huge increase in the population of Egypt and the limited agricultural area. It is also necessary to vertical expansion in agricultural production and inadditional to improve the environmental conditions in which plants are grown and to create the conditions and environmental control appropriate for the growth of these crops and are usually equipped with some environmental modification devices for environmental control such as cooling, ventilation and heating systems.
Ventilation can remove excess heat, increase air mixing, and reduce temperature stratification in the greenhouse during the summer in Egypt. Ventilation alone is not enough to maintain optimum interior temperature. Therefore, water evaporative cooling systems and fans are usually used to reduce the interior air temperature to an acceptable level. The cooling of these systems is commonly accomplished by using an electrically driven fan, pad. The fan and pad function prevent high temperature and cool the plants during hot weather. The function of shading technology is to reduce the amount of thermal radiation solar to reduce heat and because of its disadvantages is to reduce the sunlight necessary for the growth of plants so it is necessary to use independent lighting system suitable for plant.
The main objective of this study is to introduce a proposed system for cooling the greenhouse, which uses a self-contained solar cell system in its cooling client suitable for feeding the electrical load for greenhouse. Therefore, the current research aims to develop, establish and test a experimental greenhouse equipped with a cooling and ventilation control system to maintain an optimal growth for lettuce and mint plant during the autumn and winter season through:
1. Work greenhouses small and installation of internal control systems is to provide a suitable cooling system with solar cells.
2. Supplying the greenhouse with a fan ventilation system working from solar cells to control the relative humidity inside the greenhouse.
3. Supplying the system designed with internal climate control for greenhouse from the temperature and relative humidity by placing thermostat and moisture sensor to provide suitable environmental conditions for the plants inside the greenhouse.
4. Comparing of the productivity of the controled greenhouse with a traditional greenhouse designed with the same specifications and orientation.
5. Evaluating the cost of cooling and environmental control inside the greenhouse.
The obtained data of this study can be summarized as follows:
- The internal air temperature(Tin) decreased during the day time comparing with the outside air temperature and the traditional greenhouse.Such decrease, at the peak daytime, was (7 to14) dgree during the autumn and winter season decrease (10 to 20) dgree.
- The relative humidity inside the greenhouse increased during the daytime and decreased during night time as compared with outside relative humidity and the traditional greenhouse. Such increases ranged from 0.71 to 22.85% during the autumn, while the winter increases ranged from 0.16 to 12.87%.
- Using evaporative cooling system decreased the energy gained from solar radiation(Qsol), and energy lost via ventilation (Qvent) .At the peak day time, such decreases were 34.84, 20.25%, respectively.Increase the stem length of the plant, root length, consumption of the nutrient solution and yield of the cooled greenhouse than in the traditional greenhouse by 15.12%, 19.21%, 5.16% and 52.88%, respectively during the summer season for lettuce. While the percentage of increase for mint were 17.34%, 22.85%, 3.16%, 49.91%, respectively. On the other hand the increase ratio is almost equal during the winter season.
- consumption of water in the cooled greenhouse decreased comparing with the traditional greenhouse by 24.06% for the lettuce plant while the decrease percentage of mint plant reaced 29.85%. On the other hand the DROP ratio is almost equal during the winter season.
Cost analysis:
1. Prototype included (structure , polyethylene plastic , PVC pipe , submersible pump, fans, solar cell, charge controller , battery, inverter, nutrient solution, seedlings, cup of seedlings, tanks , timer , pipe of Gr and frame ).
2. The total cost for one m2 of greenhouse was about 274.15 L.E/m2. Product 150 kg/year fresh green lettuce in the area of 1 m2. The kilogram of fresh lettuce water worth 10 L.E, so the net profit was 1225.85 L.E/year.
3. 56 kg/year of fresh green mint selected in an area of 1m2. The kilogram of fresh mint water worth of 8 L.E, so the net profit was 173.85 L.E/year.
4. The total cost for one m2 of greenhouse control was about 134.27 L.E/m2.