A novel solar tower hybrid multigeneration system for coupled energy and water production: thermodynamic and exergy assessment

• A novel solar-driven generation system (Power, Water, Hydrogen, Heat) is analyzed. • The integration of the organic Rankine and Kalina cycles produces a net power of 7,678 kW. • Increasing turbine inlet pressure enhances power output but reduces the polytropic efficiency. • Freshwater and hydrogen production rates are 38.91 kg/s and 0.1106 kg/s. • An Overall energy and exergy efficiencies are 18.6% and 11.5% at steady-state. In this study, the feasibility and performance of a multigeneration solar system for electricity, fresh water, heat, and hydrogen production have been investigated. Solar thermal systems are among the promising renewable technologies that can reduce dependence on fossil fuels by utilizing the abundant solar energy source. In the proposed configuration, a solar heliostat field along with Thermal Energy Storage containing phase change materials including 59.5% LiCl and 40.5% KCl has been used to preheat several thermodynamic cycles. This system includes Kalina and organic Rankine cycles for electricity production, a four-stage desalination unit for fresh water production, and a solid oxide electrolysis unit for hydrogen production. The model has been developed in Aspen HYSYS software and detailed thermodynamic and exergy analyses have been performed for all components. The results show that this system is capable of producing 7678 kW of electricity, 56470 kW of heat, 38.91 kg/s of fresh water, and 0.1106 kg/s of hydrogen. Exergy analysis shows that the solar tower has the highest exergy destruction rate. The proposed multigeneration plant achieves an overall energy efficiency of 18.6% and an exergy efficiency of 11.5%. The proposed configuration offers a practical and sustainable solution for simultaneous production of energy and water, especially in arid and tropical regions.