Evaluation of a Geothermal-Driven Multigeneration System for Energy, Hydrogen and Fresh Water Production with LNG Cold Energy Recovery

The current work proposes an innovative multigenerational system predicated on a binary geothermal plant to generate power, distilled water, hydrogen, and liquefied natural gas. The proposed facility comprises a Kalina cycle (KC), transcritical carbon dioxide (tCO2) Rankine cycle (RC), an organic Rankine cycle (ORC), proton exchange membrane electrolyzer (PEME), multi-stage flash (MSF) desalination, and liquefied natural gas (LNG) regasification process. The thermal energy necessary for all beneficial outcomes is secured by geothermal energy. A thermodynamic evaluation of the facility is performed using energy and exergy efficiency methods. Moreover, extensive parametric analysis is performed on varying principal performance metrics, such as geothermal water temperature and mass flow rate. Findings exhibit that the plant is capable of producing 2,273 kW of electrical power, 6,320 kW of district heating, 1.784 kg/h of hydrogen, and 7.51 m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>/h of freshwater, respectively. In addition, the energy and exergy efficiency of the examined multigeneration power plant were found to be 0.73 and 0.32, respectively. Moreover, the total exergy destruction of the geothermal energy-driven power plant is computed to be 10,120.5 kW, with the LNG and KC the highest and second-highest exergy irreversibility ratios at 38.5% and 32.3%, respectively. Based on the results, it appears that combining different Processes utilizing geothermal energy is a viable option.