Iranian Research Organization for Science and Technology (IROST) Hydrogen, Fuel Cell & Energy Storage 2980-8537 12 4 2025 11 06 Thermodynamic Analysis of a Combined Solar and Geothermal Cycle for Hydrogen and Freshwater Production 243 252 1647 10.22104/hfe.2025.7165.1321 EN Ammar Jalal Abdulrazzaq Al-Tabatabaee Mechanical Engineering Department, Engineering Faculty, Urmia University, Urmia, Iran Iraj Mirzaee Mechanical Engineering Department, Engineering Faculty, Urmia University, Urmia, Iran 0000-0002-3523-5251 Morteza Khalilian Mechanical Engineering Department, Engineering Faculty, Urmia University, Urmia, Iran 0009-0003-1907-3461 Journal Article 2025 08 01 This study presents a thermodynamic assessment of a multigeneration system designed to produce power, cooling, heat, hydrogen, and freshwater. The system integrates the Organic Rankine Cycle, a single-effect absorption refrigeration system, a heat pump, a PEM electrolyzer, and a reverse osmosis (RO) unit. It leverages solar energy from two types of solar collectors, geothermal energy, and energy from a PVT (photovoltaic-thermal) collector as its primary energy sources. First, the relevant thermodynamic and thermoeconomic equations for the proposed system are introduced. The entire system is then analyzed using EES (Engineering Equation Solver) software. The system's performance is evaluated, and the impact of various parameters on the effectiveness of the multigeneration system is studied. The examination of exergy destruction in the primary cycles reveals that the evaporator in the ORC cycle experiences the highest exergy destruction rate, at 1526 kW. Furthermore, increasing the collector area and solar radiation of the solar collector results in higher rates of freshwater and hydrogen production. Additionally, an increase in the ORC turbine inlet temperature enhances freshwater and hydrogen production rates, as well as boosts turbine and TEG unit power generation. Finally, the assessment of various working fluids in the ORC cycle demonstrates that n-hexane exhibits the best performance in terms of efficiency and hydrogen and freshwater production rates. https://hfe.irost.ir/article_1647_8d420fa35754d1f1c19969c88780314d.pdf