@inproceedings{ZiemsTannertKrautz, author = {Ziems, Christian and Tannert, Daniel and Krautz, Hans Joachim}, title = {Approaches for simulation of an advanced alkaline water electrolyzer prototype}, series = {Proceedings of the 14th International Symposium on Heat Transfer and Renewable Sources of Energy, Szczecin-Miedzyzdroje, Poland, September 06-09, 2012}, booktitle = {Proceedings of the 14th International Symposium on Heat Transfer and Renewable Sources of Energy, Szczecin-Miedzyzdroje, Poland, September 06-09, 2012}, publisher = {Wydawnistwo Uczelnianie ZUT}, address = {Szczecinie}, isbn = {978-83-7663-121-9}, language = {en} } @misc{VoigtFischerTannertetal., author = {Voigt, Andr{\´e} and Fischer, Ulrich and Tannert, Daniel and Krautz, Hans Joachim}, title = {Analyse erneuerbarer P2H2 Energiesystemkonfigurationen unter Verwendung von Matlab}, series = {Nutzung regenerativer Energiequellen und Wasserstofftechnik 2017 ; 24. Symposium Nutzung Regenerativer Energiequellen und Wasserstofftechnik, Stralsund, 09. bis 11. November 2017}, journal = {Nutzung regenerativer Energiequellen und Wasserstofftechnik 2017 ; 24. Symposium Nutzung Regenerativer Energiequellen und Wasserstofftechnik, Stralsund, 09. bis 11. November 2017}, publisher = {HOST - Hochschule Stralsund}, address = {Stralsund}, isbn = {978-3-9817740-3-0}, pages = {143 -- 147}, language = {de} } @inproceedings{ZiemsKrautz, author = {Ziems, Christian and Krautz, Hans Joachim}, title = {Alkalische Elektrolyse - Kernkomponente eines Hybridkraftwerks im Kontext Power to Gas}, language = {de} } @inproceedings{ZiemsKrautz, author = {Ziems, Christian and Krautz, Hans Joachim}, title = {Alkalische Druckelektrolyse - Schl{\"u}sseltechnologie f{\"u}r zuk{\"u}nftige Energie- und Speicherkonzepte}, series = {4. Energiefachtagung, Cottbus, 2012}, booktitle = {4. Energiefachtagung, Cottbus, 2012}, language = {de} } @inproceedings{WenskeTillmannKrautz, author = {Wenske, Michael and Tillmann, Christine and Krautz, Hans Joachim}, title = {Aktuelle Entwicklungen der alkalischen Elektrolyse}, series = {4. Energiefachtagung, Cottbus, 2012}, booktitle = {4. Energiefachtagung, Cottbus, 2012}, language = {de} } @phdthesis{Missagia, author = {Missagia, Bruna}, title = {Agricultural and forestry residues for decentralized energy generation in Brazil}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus-25180}, pages = {214}, language = {en} } @misc{SharmaRoentzschShahi, author = {Sharma, Prerana and R{\"o}ntzsch, Lars and Shahi, Vinod K.}, title = {Advancements towards optimization of metal-organic framework-based polymer electrolyte membranes for aqueous redox flow batteries}, series = {Journal of materials chemistry : A, materials for energy and sustainability}, volume = {13}, journal = {Journal of materials chemistry : A, materials for energy and sustainability}, number = {17}, publisher = {Royal Society of Chemistry (RSC)}, address = {London}, issn = {2050-7488}, doi = {10.1039/D4TA08720H}, pages = {11952 -- 11988}, abstract = {Aqueous redox flow batteries (ARFBs) are considered a potential technology for large-scale energy storage owing to their eco-friendliness, high current density, and tuneable capacity. Polymer electrolyte membranes (PEMs) are vital components of ARFB, but they suffer from significant capacity/efficiency deterioration due to a lack of advancement in structural framing. To enhance the effectiveness of ARFBs, various membrane types have been optimized. However, the development of an efficient PEM remains a significant problem. Metal-organic frameworks (MOFs) made up of metal sites and organic linkers have gained significant scientific interest. As a result of their large surface area, adjustable pore diameters, and customized functionality, MOF-based PEMs are regarded as effective separators for ARFB. This review covers the state of the art MOF-based PEMs as ARFB separators. In recent years, significant efforts have been made to utilize the unique characteristics of MOFs as they not only improve the conductivity (attributed to their 3D channel structure) and gradient distribution in the polymer framework but also stabilize and mitigate active species cross-over by regulating the effective pore size. The aforementioned tactics can stimulate more research on energy storage technologies and provide future insight into the development and design of size-sieving separators for ARFB.}, language = {en} } @misc{SakkasGillungThummaretal., author = {Sakkas, Nikolaos P. and Gillung, Frank and Thummar, Krunalkumar and Abang, Roger and R{\"o}ntzsch, Lars}, title = {Advanced pressurized alkaline water electrolysis at high temperatures up to 130 °C}, series = {International journal of hydrogen energy}, volume = {149}, journal = {International journal of hydrogen energy}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2025.150075}, pages = {1 -- 12}, abstract = {Operating alkaline water electrolysers above 100 °C improves electrolyte conductivity and reaction kinetics significantly. To examine alkaline water electrolysis in this area in more detail a high-temperature pressurized test rig is designed and constructed. Nickel (Ni) foam electrodes coated with Raney nickel (Raney Ni) or nickel manganese (NiMn) and expanded Ni mesh electrodes coated with nickel(II) oxide (NiO) are utilized and the effect of electrolyte flow rate, electrode structure, pressure and temperature variation on the cell performance at temperatures up to 130 °C and pressures up to 16 bar are investigated. At the maximum current density of 1.67 A/cm2, 110 °C and 16 bar the electrode combination of Raney Ni coated Ni foam as cathode and NiO coated expanded Ni mesh electrode as anode attain the best outcome with a cell voltage of 2.29 V. In a 70 h duration test three-dimensional (3D) Ni foam electrodes with Raney Ni cathode and NiMn anode catalyst show a moderate cell degradation of 9.26 μV/h.}, language = {en} } @misc{SampangiJarubulaElasmaretal., author = {Sampangi, Shiva Kumar and Jarubula, Charath Krishna and Elasmar, Mohamed and R{\"o}ntzsch, Lars}, title = {Advanced anion exchange membrane electrolyser with 360 cm² active cell area}, series = {EFCF 2025 : Fuel Cells, Electrolysers \& H2 Processing}, journal = {EFCF 2025 : Fuel Cells, Electrolysers \& H2 Processing}, publisher = {European Fuel Cell Forum AG}, address = {Luzern}, doi = {10.5281/zenodo.17244119}, pages = {1 -- 6}, abstract = {Anion Exchange Membrane Water Electrolysis (AEMWE) has emerged as a promising technology for generating green hydrogen, particularly using intermittent renewable energy sources. AEMWE offers a compelling opportunity for cost-effective and sustainable hydrogen production by combining the advantages of traditional alkaline water electrolysis, such as the use of abundant and low-cost catalysts, with the benefits of Proton Exchange Membrane (PEM) electrolysis, which includes membrane separation with pure or low-concentration alkaline water and operation at high current densities. However, the widespread commercialization of AEMWE remains in its early stages, with small-scale active cell areas (less than 300 cm²) and ongoing challenges related to performance and durability. Consequently, it is vital to develop high-performance, durable AEMWE cells with larger active areas to facilitate the broader adoption of this technology. This contribution presents our recent progress in AEMWE, focusing on the development of cells with an active area of up to 360 cm². In particular, we are advancing AEMWE technology to Technology Readiness Level (TRL) 5/6, incorporating precious metal-free catalysts and advanced membranes to enhance the flexibility and efficiency of hydrogen production. As part of this effort, we have designed and experimentally tested a 100 cm² AEMWE cell and conceptualized and designed a 4-kW short-stack with a total active cell area of 1800 cm², as shown in Figure. 1, for high-pressure operation at 30 bar. Our ongoing efforts includes the laboratory testing of this newly designed stack at high pressure operation and evaluating its electrochemical performance and durability up to 1,000 h continuous operation using precious metal-free electrocatalysts.}, language = {en} } @misc{DahashMieckOchsetal., author = {Dahash, Abdulrahman and Mieck, Sebastian and Ochs, Fabian and Krautz, Hans Joachim}, title = {A comparative study of two simulation tools for the technical feasibility in terms of modeling district heating systems: An optimization case study}, series = {Simulation Modelling Practice and Theory}, volume = {91}, journal = {Simulation Modelling Practice and Theory}, issn = {1569-190X}, doi = {10.1016/j.simpat.2018.11.008}, pages = {48 -- 68}, abstract = {District heating dynamic models arise as an alternative approach to in-situ experimental investigations. The main advantage of dynamic modeling and simulation is the possibility to avoid technical and operational risks that might occur during in-situ experimental investigations (e.g. heat demand is not met, damages in the energy systems etc.). Within this study, the authors present two models for an existing district heating system in Cottbus, Germany. One model is developed using the tool EBSILON Professional, while the other one is developed using the Simscape toolbox for physical modeling in Matlab/Simulink. The models were experimentally validated against measured data from the considered district heating system. The results show that the Simscape model has a better fit and better response than the EBSILON model. Yet, some discrepancies were found between the measured and the simulated data and, therefore, the uncertainties of the models were addressed. A comparative study between both tools is presented. The EBSILON models permit only unidirectional flow, whereas the Simscape toolbox permits reverse flow. Nevertheless, the EBSILON model outperforms the Simscape model in computation time. In addition, this study presents an approach for dynamic thermo-hydraulic modeling of district heating networks. This approach is utilized to examine the role of district heating networks as heat storage as an optimization configuration. The numerical results show less start-ups for additional heat sources. Yet, higher heat losses from the network are observed due to the installation of unburied pipelines.}, language = {en} }