Multi-generation systems powered by renewable solar energy have proven to be cutting-edge solutions for decreasing greenhouse gas emissions. This paper proposes a novel electricity, heat, and green hydrogen poly-generation system. The innovative design consists of solar photovoltaic thermal (PVT) collectors with organic Rankine cycle (ORC), proton exchange membrane (PEM) electrolyzer, and liquefied natural gas (LNG). Using an Engineering Equations Solver (EES), a thermodynamic (energy, exergy) and economic evaluation of the proposed plant is carried out. Non-dominated sorting genetic algorithm II (NSGA-II) is used to estimate the optimal results for the proposed system. The objective functions are energy efficiency, cost rate, and net output power. The results show that the proposed system operates with an exergy efficiency of 16.24%, a cost rate of 4.48 $/hr, and a net electrical power of 33.32 kW under the optimal conditions, based on the TOPSIS (a technique for order performance by similarity to ideal solution) decision-making process. This study also provides a numerical examination of the new suggested renewable multi-generation system for different climate zones (hot desert climate, cold semi-desert climate, Marine West Coast Climate, and temperate oceanic climate). The results also reveal that the most critical monthly net electrical power generated by PVT collectors in Tehran, Dubai, Paris, and London regions is 9300 kWh, 8666 kWh, 7050 kWh, and 7040 kWh, respectively. Furthermore, the maximum monthly hydrogen produced for the areas above is 62 kg, 75 kg, 17 kg, and 14 kg. Moreover, the Sankey diagram indicates that the solar photovoltaic thermal collectors system has the highest irreversibility.
