Fuente: Sustainability - Revista científica (MDPI) Sustainability, Vol. 17, Pages 11298: Solar-Powered RO–Hydroponic Net House: A Scalable Model for Water-Efficient Tomato Production in Arid Regions
Sustainability doi: 10.3390/su172411298
Authors:
Arash Nejatian
Abdul Aziz Niane
Mohamed Makkawi
Khaled Al-Sham'aa
Shamma Abdulla Rahma Al Shamsi
Tahra Saeed Ali Mohamed Al Naqbi
Haliema Yousif Hassan Ibrahim
Jassem Essa Juma

This study assessed six tomato (Solanum lycopersicum L.) cultivars within an integrated solar-powered closed hydroponic system in Al Dhaid, UAE (25°16′11.2″ N, 55°55′52.2″ E). The system combined an insect-proof net house, closed hydroponics, root-zone cooling, ultra-low-energy drip irrigation, and a cost-effective solar-powered reverse osmosis (RO) desalination unit to address salinity constraints. The cultivars, selected for their adaptability to controlled environments in the UAE, were evaluated for yield, water-use efficiency (WUE), and fertilizer-use efficiency (FUE). Among them, Torcida recorded the highest mean yield (0.619 kg/m2/harvest), WUE (27.1 kg/m3), FUE (26.5 kg fruit/kg fertilizer), and marketable fruit ratio (66.3%), followed by Roenza, Eviva, and SV 4129 TH; Lamina was intermediate, while Saley, a bushy type, produced the lowest yield. The top cultivars achieved cumulative yields exceeding 7 kg/m2—surpassing regional open-field benchmarks (4–5 kg/m2; 3–6 kg/m3). Compared with conventional cooled hydroponic greenhouses (3.5 kg/plant; 8 kg/m3), the system demonstrated similar productivity using three times less water. The RO unit produced water at baseline 1.05 USD/m3—58–68% below regional tariffs—while minimizing reliance on grid electricity and mechanical cooling. Overall, the integrated solar-powered hydroponic–RO model proved technically reliable, resource-efficient, and economically viable, offering a scalable solution for sustainable vegetable production in hyper-arid regions.