A Geothermal Multigeneration System Integrating an ORC Configuration with an Open-Feed Heater for Electricity/H2/Cooling Production: Techno-Economic Optimization Using a Genetic Algorithm

Abstract
This research presents a novel geothermal-based multigeneration framework engineered to supply electric energy, hydrogen gas, and chilled water. The framework incorporates an organic Rankine cycle (ORC) with an open feed heater (OFH), a Kalina cycle (KC), an absorption refrigeration cycle (ARC), and a PEM electrolyzer (PEME). A comprehensive thermodynamic and economic evaluation is performed, followed by a multi-objective optimization using NSGA-II in MATLAB to maximize exergetic performance and minimize cost. Key parameters include geothermal fluid temperature, mass flow rate, ORC turbine inlet temperature, and evaporator pinch point temperature difference (PPTD). The ORC exhibits the highest exergy destruction (42%), trailed by the KC (26%) and PEME (19%), while the ARC contributes the least (13%). Elevating geothermal fluid temperature significantly enhances exergy efficiency and hydrogen output, although costs increase.

Author
Dyana Aziz Bayz

DOI
https://doi.org/10.1016/j.ijrefrig.2025.05.017

Publisher

ISSN
1879-2081

Publish Date: