@misc{ThummarAbangMenzeletal., author = {Thummar, Krunalkumar and Abang, Roger Atini and Menzel, Katharina and Groot, Matheus Theodorus de}, title = {Coupling a Chlor-Alkali Membrane Electrolyzer Cell to a Wind Energy Source: Dynamic Modeling and Simulations}, series = {Energies}, volume = {15}, journal = {Energies}, number = {2}, issn = {1996-1073}, doi = {10.3390/en15020606}, pages = {1 -- 26}, abstract = {Renewable energy sources are becoming a greater component of the electrical mix, while being significantly more volatile than conventional energy sources. As a result, net stability and availability pose significant challenges. Energy-intensive processes, such as chlor-alkali electrolysis, can potentially adjust their consumption to the available power, which is known as demand side management or demand response. In this study, a dynamic model of a chlor-alkali membrane cell is developed to assess the flexible potential of the membrane cell. Several improvements to previously published models were made, making the model more representative of state-of-the-art CA plants. By coupling the model with a wind power profile, the current and potential level over the course of a day was simulated. The simulation results show that the required ramp rates are within the regular operating possibilities of the plant for most of the time and that the electrolyte concentrations in the cell can be kept at the right level by varying inlet flows and concentrations. This means that a CA plant can indeed be flexibly operated in the future energy system.}, 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} }