Е-Публикации
Технически университет - София

Abstract: The article discusses a regenerative heat exchange system for a solid oxide electrolyzer cell (SOEC) used in the production of green hydrogen. The heating system comprises four heat exchangers, one condenser heat exchanger, and a mixer evaporator. A pump and two throttle valves have been added to separate the hydrogen at an elevated steam condensation temperature. Assuming steady flow, a thermodynamic analysis was performed to validate the design and to predict the main parameters of the heating system. Numerical optimization was then used to determine the optimal temperature distribution, ensuring the lowest possible additional external energy requirement for the regenerative system. The proportions of energy gained through heat exchange were determined, and their distribution analyzed. The calculated thermal efficiency of the regenerative system is 75%, while its exergy efficiency is 73%. These results can be applied to optimize the design of heat exchangers for hydrogen production systems using SOECs.

References

1. Armaroli N. Balzani V. The Hydrogen Issue ChemSusChem 2011 4 21 36 10.1002/cssc.201000182 21226208
2. Penner S.S. Steps toward the Hydrogen Economy Energy 2006 31 33 43 10.1016/j.energy.2004.04.060
3. Bockris J.O. A Hydrogen Economy Science 1972 176 1323 17820918 10.1126/science.176.4041.1323
4. Ni M. Leung M. Leung D. Technological Development of Hydrogen Production by Solid Oxide Electrolyzer Cell (SOEC) Int. J. Hydrogen Energy 2008 33 2337 2354 10.1016/j.ijhydene.2008.02.048
5. Hagen A. Caldogno R. Capotondo F. Sun X. Metal Supported Electrolysis Cells Energies 2022 15 2045 10.3390/en15062045
6. Elrhoul D. Naveiro M. Romero Gómez M. Thermo-Economic Comparison between Three Different Electrolysis Technologies Powered by a Conventional Organic Rankine Cycle for the Green Hydrogen Production Onboard Liquefied Natural Gas Carriers J. Mar. Sci. Eng. 2024 12 1287 10.3390/jmse12081287
7. Lang S. Yuan J. Zhang H. Optimally Splitting Solar Spectrums by Concentrating Solar Spectrums Splitter for Hydrogen Production via Solid Oxide Electrolysis Cell Energies 2024 17 2067 10.3390/en17092067
8. Liu H. Shuai W. Yao Z. Xuan J. Ni M. Xiao G. Xu H. Optimization of Solid Oxide Electrolysis Cells Using Concentrated Solar-Thermal Energy Storage: A Hybrid Deep Learning Approach Appl. Energy 2025 377 124610 10.1016/j.apenergy.2024.124610
9. Chen Y. Wu X. Hu H. Zhang J. System Level Performance Analysis and Parameter Optimization of Hydrogen Production Based on Solid Oxide Electrolytic Cell Appl. Energy 2023 347 121329 10.1016/j.apenergy.2023.121329
10. Wu Z. Si Y. Li S. Ma L. Gao M. Optimization Method for Economical Operation of SOEC Considering Thermal Balance Efficiency Characteristics Proceedings of the 2022 4th International Conference on Power and Energy Technology (ICPET) Beijing, China 28–31 July 2022 IEEE Piscataway, NJ, USA 2022 698 704
11. Wang H. Xiao L. Liu Y. Zhang X. Zhou R. Liu F. Yuan J. Performance and Thermal Stress Evaluation of Full-Scale SOEC Stack Using Multi-Physics Modeling Method Energies 2023 16 7720 10.3390/en16237720
12. Abousalmia A. Karagoz S. Design and Simulation of an Integrated Process for the Co-Production of Power, Hydrogen, and DME by Using an Electrolyzer’s System Energies 2025 18 2446 10.3390/en18102446
13. Jeong K. Hong J. Kim D. Ji J. SOFC-0205—Design and Optimization of a Solid Oxide Electrolysis Cell System and Its Behavior Under Load Following Conditions Available online: https://ecs.confex.com/ecs/sofc2025/meetingapp.cgi/Paper/206073 (accessed on 10 June 2025)
14. Tanozzi F. Sharma S. Maréchal F. Desideri U. 3D Design and Optimization of Heat Exchanger Network for Solid Oxide Fuel Cell-Gas Turbine in Hybrid Electric Vehicles Appl. Therm. Eng. 2019 163 114310 10.1016/j.applthermaleng.2019.114310
15. AlZahrani A.A. Dincer I. Modeling and Performance Optimization of a Solid Oxide Electrolysis System for Hydrogen Production Appl. Energy 2018 225 471 485 10.1016/j.apenergy.2018.04.124
16. Mohammadi A. Mehrpooya M. Techno-Economic Analysis of Hydrogen Production by Solid Oxide Electrolyzer Coupled with Dish Collector Energy Convers. Manag. 2018 173 167 178 10.1016/j.enconman.2018.07.073
17. Cui T. Zhu J. Lyu Z. Han M. Sun K. Liu Y. Ni M. Efficiency Analysis and Operating Condition Optimization of Solid Oxide Electrolysis System Coupled with Different External Heat Sources Energy Convers. Manag. 2023 279 116727 10.1016/j.enconman.2023.116727
18. Daneshpour R. Mehrpooya M. Design and Optimization of a Combined Solar Thermophotovoltaic Power Generation and Solid Oxide Electrolyser for Hydrogen Production Energy Convers. Manag. 2018 176 274 286 10.1016/j.enconman.2018.09.033
19. Park Y.J. Min G. Hong J. Operational Guidelines for a Residential Solid Oxide Fuel Cell-Combined Heat and Power System with an Optimal System Layout Design Energy Convers. Manag. 2021 246 114666 10.1016/j.enconman.2021.114666
20. Min G. Park Y.J. Hong J. Thermodynamic Analysis of a Solid Oxide Co-Electrolysis Cell System for Its Optimal Thermal Integration with External Heat Supply Energy Convers. Manag. 2020 225 113381 10.1016/j.enconman.2020.113381
21. Min G. Choi S. Hong J. A Review of Solid Oxide Steam-Electrolysis Cell Systems: Thermodynamics and Thermal Integration Appl. Energy 2022 328 120145 10.1016/j.apenergy.2022.120145
22. Wang F. Wang L. Ou Y. Lei X. Yuan J. Liu X. Zhu Y. Thermodynamic Analysis of Solid Oxide Electrolyzer Integration with Engine Waste Heat Recovery for Hydrogen Production Case Stud. Therm. Eng. 2021 27 101240 10.1016/j.csite.2021.101240
23. Ploner A. Hauch A. Pylypko S. Di Iorio S. Cubizolles G. Mougin J. Optimization of Solid Oxide Cells and Stacks for Reversible Operation ECS Trans. 2019 91 2517 2526 10.1149/09101.2517ecst
24. Lang M. Lee Y.S. Lee I.S. Szabo P. Hong J. Cho J. Costa R. Analysis of Electrochemical Degradation Phenomena of SOC Stacks Operated in Reversible SOFC/SOEC Cycling Mode J. Electrochem. Soc. 2023 170 114516 10.1149/1945-7111/ad09f3
25. Rizvandi O.B. Noponen M. Frandsen H.L. Sun X. Numerical Investigation of Electrochemical Performance of Commercial Solid Oxide Cell Stacks Int. J. Hydrogen Energy 2025 102 830 844 10.1016/j.ijhydene.2025.01.101
26. McCarty R.D. Hord J. Roder H.M. Selected Properties of Hydrogen (Engineering Design Data) U.S. Government Printing Office Washington, DC, USA 1981
27. Wagner W. Kretzschmar H.-J. International Steam Tables Properties of Water and Steam Based on the Industrial Formulation IAPWS-IF97 2nd ed. Springer Berlin/Heidelberg, Germany 2008
28. Wagner W. Kruse A. Properties of Water and Steam/Zustandsgrößen von Wasser Und Wasserdampf Springer Berlin/Heidelberg, Germany 1998 978-3-662-03530-6
29. Wark K. Thermodynamics 4th ed. McGraw-Hill New York, NY, USA 1983
30. Annaratone D. Handbook for Heat Exchangers and Tube Banks Design Springer Berlin/Heidelberg, Germany 2010 978-3-642-13308-4
31. Amiri J. Solid Oxide Electrolysis Cell (SOEC) SOECs: The Answer to Our Hydrogen Needs? Available online: https://www.linkedin.com/feed/update/urn:li:activity:7104433077220773888/ (accessed on 14 December 2024)
32. Cengel Y. Boles M. Kanoglu M. Thermodynamics: An Engineering Approach 10th ed. McGraw New York, NY, USA 2022 1265898502
33. Brabandt J. Posdziech O. System Approach of a Pressurized High-Temperature Electrolysis ECS Trans. 2017 78 2987 2995 10.1149/07801.2987ecst
34. Gruber M. Weinbrecht P. Biffar L. Harth S. Trimis D. Brabandt J. Posdziech O. Blumentritt R. Power-to-Gas through Thermal Integration of High-Temperature Steam Electrolysis and Carbon Dioxide Methanation—Experimental Results Fuel Process. Technol. 2018 181 61 74 10.1016/j.fuproc.2018.09.003
35. Saarinen V. Pennanen J. Kotisaari M. Thomann O. Himanen O. Di Iorio S. Hanoux P. Aicart J. Couturier K. Sun X. et al. Design, Manufacturing, and Operation of Movable 2 × 10 KW Size RSOC System Fuel Cells 2021 21 477 487 10.1002/fuce.202100021

Issue