Performance optimization of the hybrid HDH-RO desalination system powered by photovoltaic-thermal modules using solar dish concentrators

The lack of pure water and electricity in remote regions pushes to simulate of an innovative high-productive hybrid desalination system with the lowest power consumption rates, and this represents a major challenge recently. To achieve this goal, the present study aimed to simulate an innovative hybrid HDH-RO desalination system powered by photovoltaic-thermal modules and a solar dish concentrator. The proposed innovative hybrid system is characterized by integrating two common technologies for pure water production namely: HDH desalination unit and RO desalination unit with an energy recovery device. In order to achieve the highest production rates of pure water with the lowest possible rates of power consumption, the proposed innovative hybrid system was provided with photovoltaic-thermal modules and solar dish concentrators, as preheating units to heat the feed water before its entering the HDH-RO desalination unit. The photovoltaic-thermal modules have a dual function: enhancing the performance of photoelectric conversion, and simultaneously preheating the feed water before it enters the spiral coil of the solar dish concentrator. The solar dish concentrator with a solar thermal receiver was purposed to raise the feed water temperatures before it enters the HDH-RO desalination unit, to improve evaporation rates within the HDH unit as well as increase the rates of water permeating for the RO unit. The results indicated that the utilization of the photovoltaic-thermal modules and solar dish concentrators, as preheating units to heat the feed water before its entering the HDH-RO desalination unit has positive effects in terms of increasing the pure water productivity and reducing the rates of power consumption. The productivity of pure water for the innovative hybrid system ranged between 793 and 861 kg/h, with an improvement of 25.9%-36.6% compared to the traditional RO unit without adding any other modifications. Also, the average improvement in the water recovery ratio reached 31.7%. Moreover, the savings in the specific power consumption for utilizing the proposed innovative hybrid system varied between 12.9% and 13.9% compared to the traditional RO unit.