Analysis and calculation of Germany's climate politics and hydrogen strategy, with a focus on the technical demand for hydrogen implementation through a case study of the chemical industry that engages multiple stakeholders.

This work presents advancements in a rotating glow-to-arc plasma reactor, designed for stable gas conversion of robust molecules like CO₂, N₂, and CH₄. Plasma-based systems play a critical role in Power-to-X research, offering electrified, sustainable pathways for industrial gas conversion. Here, we scaled the reactor’s power from 200 W to 1.2 kW in a CO₂ plasma, which introduced instability due to uplift forces and arc behavior. These were mitigated by integrating silicon carbide (SiC) ceramic foam as a mechanical restriction, significantly enhancing stability by reducing arc movement, confining convection, and balancing volumetric flow within the arc. Using high-speed camera analysis and in situ electronic frequency measurements, we identified dominant frequencies tied to operational parameters, supporting potential in operando monitoring and control. Arc-rotation frequencies from 5 to 50 Hz and higher frequencies (500 to 2700 Hz) related to arc chattering reveal the system’s dynamic response to power and flow changes. Furthermore, refining the specific energy input ($SEI$) to account for plasma residence time allowed for a more precise calculation of effective $SEI$, optimizing energy delivery to target molecules. Our findings underscore the reactor’s promise for scalable, efficient gas conversion in sustainable energy applications.

Direct air capture (DAC) technologies offer a promising approach to mitigate anthropogenic climate change by enabling net negative emissions. CO₂ absorption using NaOH represents an efficient solution within the proposed BlueFire carbon cycle, which integrates DAC with plasma technology for syngas production. Optimizing a DAC plant control relies on understanding the pH profile as a key parameter. A bubble column absorption model with pure CO₂ was experimentally adapted for a counter‐current flow setup with ambient air, reproducing a staged pH decrease. An optimal absorption endpoint was determined by identifying the maximum slope of the pH decline, indicating high reaction progress. X‐ray diffraction analysis of the absorption products validated the theoretical model of carbonate formation.

In this research article, a novel inverter design was developed to enable higher efficiency and higher power density in dielectric barrier discharge (DBD) plasma reactor for gas conversion. DBD plasma reactors generate nonthermal plasmas that enable electrified chemical production, including syngas synthesis from CO₂, ammonia synthesis, and dry reforming of methane. Achieving high conversion efficiency requires optimization of the specific energy input (SEI) while maintaining overall energy efficiency. Plasma catalysis, however, is highly sensitive to discharge homogeneity, where minor variations in system parameters can significantly alter performance. One of the important aspects of overall performance is the plasma driver and the conventional AC power supplies for DBD applications are bulky, cascaded, cost-inefficient, and typically achieve less than 70% efficiency at rated power. Inaccuracies in SEI estimation further arise when inverter efficiency is neglected. The proposed inverter utilizes transformer secondary leakage parameters to improve performance. The inverter achieves efficiencies above 80%, doubles the power density for a rated output of $1{\,}\mathrm {kW}$ , and reduces inverter cost by approximately 30%. Experimental validation was performed on a coaxial-bed DBD reactor operated at $160{\,}\mathrm {kHz}$ , $14{\,}\mathrm {kV}$ , and $350{\,}\mathrm {W}$ , achieving an efficiency of 84%. These results demonstrate the potential of the proposed inverter to enhance DBD plasma processes, while further investigation into discharge characteristics at full rated power are still under investigation.