Techno-economic and Environmental Assessment of a Solar-powered Multi-generation System for a Sustainable Energy, Hydrogen and Fresh-water Production

This study presents a comprehensive 4E (energy, exergy, economic, and exergo-environmental) analysis of a solar-powered multi-generation system (MGS) that integrates parabolic trough collectors (PTCs), thermal energy storage (TES), an organic Rankine cycle (ORC), an absorption refrigeration cycle (ARC), a proton exchange membrane electrolyzer (PEME), and a reverse osmosis (RO) unit to simultaneously produce electricity, cooling, potable water, and hydrogen. A complete thermodynamic model is developed in Engineering Equation Solver (EES) to evaluate the system from technical, economic, and environmental perspectives. Results indicate that the MGS can convert solar energy into multiple outputs with energy and exergy efficiencies of 12.2% and 4.3%, respectively. The highest and lowest energy efficiencies are found in PEME (58.6%) and ORC (7.4%), while the highest and lowest exergy efficiencies are related to PEME (57.4%) and PTC (11.9%), respectively. Despite notable environmental impacts from the complex subsystems (particularly PTC and PEME), the system demonstrates strong economic performance with a net present value of approximately USD 8 million, an internal rate of return of 30%, and a payback period of 3.8 years. Sensitivity analysis shows that increasing solar radiation reduces the number of required PTCs and shortens payback time, with less effect on energy and exergy efficiencies due to increased thermal and radiative losses.