In the coming years, green energy generation and effective use of the energy source methods that are renewable energy-based multigeneration systems are becoming more significant because of environmental concerns. This study proposes a new flash-binary geothermal power plant that is united with a steam cycle, a Rankine cycle (RC) with carbon dioxide (CO2), a desalination unit, and a Proton Exchange Membrane (PEM) electrolyzer, to generate beneficial outputs, which are power, hydrogen, hot and clean water. To examine and investigate the energy efficiency, exergy efficiency, cost ratio, and emission rate of the whole plant and subsystems, thermodynamic, economic, and environmental impact analyzes are applied comprehensively. With this line perspective, the exergy destruction rate of the modeled system's parts is determined. In addition, CO2 emission rates are investigated for diverse energy generation scenarios. Next, parametric research is executed to research the impacts of changes in some important factors on plant efficiency and cost. The findings of the analysis demonstrate that the amount of the total power rate of the combined plant is found to be 1639 kW, while the hydrogen generation rate is computed as 0.002081 kgs(-1). As well, the energetic and exergetic efficiency of the whole plant is figured as 52.01% and 29.45%, respectively. The total cost of the entire plant is found to be 139.6 $/h. In conclusion, the energetic performance of the multigeneration plant is found to be significantly greater than that of the single-generation plant. (C) 2022 Elsevier Ltd. All rights reserved.