The objectives of the present study were to construct and evaluate the performance of a hydroponic unit for intensive barley green fodder production. The constructed hydroponic system included lighting unit to provide plants with its lighting requirement, cooling and air conditioning unit to conserve the appropriate microclimate conditions to propagate a healthy plants and aeration and CO 2 proportioning unit to enhance the root-zone media with its air balance to achieve the plant stress. The

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... rformance of the constructed hydroponic unit was studied under some different technical parameters (growing period, aeration rate, with and without nutrient solution addition and with and without CO 2 injection). The performance of the constructed hydroponic unit was evaluated in terms of total yield, yield quality, water use efficiency, energy requirements, operational cost and net profit. The experimental results reveal that total yield (4646.4 kg/period), plant moisture content (92.13%), water use efficiency (156.028 g/l) and net profit (8256 LE/period) were in the optimum region under conditions of 8.0 days growing period, 2 hr./day aeration rate, with both nutrient solution addition and CO 2 injection. While the protein percentage (18.29%) was optimum under conditions of 5.0 days growing period, 1 hr./day aeration rate, with both nutrient solution addition and CO 2 injection. Meanwhile dry matter (21.12%) was optimum under conditions of 5.0 days growing period, 2 hr./day aeration rate, without neither nutrient solution addition nor CO 2 injection.