Hydrogen, Fuel Cell & Energy Storage

Hydrogen, Fuel Cell & Energy Storage

Energetic and Exergetic Analysis of a Geothermal Energy System for Multigeneration Applications: A Thermodynamic Perspective

Document Type : Research Paper

Authors
Mechanical Engineering Department, Faculty of Engineering, Urmia University, Urmia, Iran
10.22104/hfe.2025.7169.1324
Abstract
Recent research has increasingly focused on high-efficiency systems powered by renewable energy sources to address global warming, prevent ozone layer depletion, and ensure stable and accessible energy supplies. Among these sources, geothermal energy stands out for its ability to power thermodynamic systems capable of generating multiple outputs. The efficiency of a stand-alone flash-binary geothermal power plant decreases due to input energy losses. To enhance overall performance and reduce costs, structural modifications and waste heat recovery techniques can be implemented. This study proposes and investigates an innovative waste heat recovery system integrated into a dual-flash binary geothermal power plant. The combined system incorporates a Rankine cycle and a proton exchange membrane electrolyzer. The system focuses on two major processes: converting waste heat into power and producing hydrogen from the generated power. Its feasibility is evaluated from thermodynamic and economic perspectives. The system analysis was performed using EES (Engineering Equation Solver) software. Results indicate energy and exergy efficiencies of 23.97% and 35.35%, respectively. Moreover, the total power generated by the system, incorporating two turbines and two thermoelectric generators (TEGs), is 5981 kW. The system also produces hydrogen at a rate of 0.0295 kg/s. Moreover, based on the exergy destruction analysis, TEG 2 and the compressor exhibit the highest rates of exergy destruction.
Keywords
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