Germany

This study examines the pricing and assesses resilience methods in hydrogen supply chains by thoroughly analyzing two main disruption scenarios. The model examines a scenario in which a hydrogen production company depends on a Renewable Power plant (RP) for its electricity supply. Ensuring a steady and efficient hydrogen supply chain is crucial but outages at renewable power sources provide substantial obstacles to sustainability and operational continuity. Therefore in the event of disruptions at the RP the company has two options for maintaining resilience: either sourcing electricity from a Fossil fuel Power plant (FP) through a grid network to continue hydrogen production or purchasing hydrogen directly from another company and utilizing third-party transportation for delivery. Using a game theoretic approach we examine how different methods affect demand satisfaction cost implications and environmental sustainability. The study employs sensitivity analysis to evaluate the impact of different disruption probabilities on each scenario. In addition a unique sensitivity analysis is performed to examine the resilience of transmission security to withstand disruptions. This study evaluates how investments in security measures affect the strength and stability of the supply chain in various scenarios of disruption. Our research suggests that the first scenario offers greater reliability and cost-effectiveness along with a higher resilience rate compared to the second scenario. Furthermore the examination of the environmental impact shows that the first scenario has a smaller amount of CO2 emissions per kg of hydrogen. This study offers important insights for supply chain managers to optimize resilience measures hence improving reliability reducing costs and minimizing environmental effects.

Currently local regulations governing hydrogen installations vary by geographical region and by country leading to discrepancies in safety and separation distance requirements for similar hydrogen systems. This work carried out in the frame of IEA TCP H2 Task 43 (IEA TCP H2 2022) aims to provide an overview of various methodologies and recommendations established for risk management and consequence assessment in the event of accidental scenarios. It focuses on a case study involving industrial electrolyzers utilizing alkaline and PEM technologies. The research incorporates lessons learned from past incidents offers recommendations for mitigation measures reviews existing methodologies and highlights areas of divergence. Additionally it proposes strategies for harmonization. The study also emphasizes the most significant scenarios and the corresponding leakage sizes

In order to minimize emissions of the aerospace sector and thus its impact on the climate several novel concepts of propulsion systems for aircraft are being developed. Many of these concepts do not use an energy source based on the combustion of hydrocarbons but other means of energy generation and storage like hydrogen fuel cells and corresponding hydrogen storage systems. The use of hydrogen as a primary energy carrier in aircraft poses novel and different hazards when compared to conventional propulsion and fuel storage systems. The study described in the present paper identifies analyzes and evaluates failure conditions and corresponding hazards that are associated with the electrified propulsion systems. Mitigation strategies to prevent failures to occur or decrease their severity are recommended. The effects of the assessed failures on aircraft crew and occupants are classified as catastrophic hazardous or major as defined in the according Certification Specifications. Failure Conditions occurring at the aircraft system and subsystem levels are considered and their effect on the aircraft and propulsion system is assessed. The hazards identified mostly emerge due to the properties of the gaseous or liquid hydrogen. They include the flammability of gaseous hydrogen and the very low temperatures of cryogenic liquid hydrogen as well as the installation of high voltage power infrastructure and high capacity heat exchangers.

A two-stage system is used for hydrogen (H2) and methane (CH4) production from sucrose wastewater. The H2- producing reactor is operated at pH temperature (T) and hydraulic retention time (HRT) of 5.5 35 ◦C 24 h respectively. While operating conditions of 7–8 pH 35 ◦C T and 144 h HRT are used to conduct the CH4 production stage. The effects of two different parameters as sucrose concentration (5 10 and 20 g/L) and addition of ferrous ions (60 and 120 mg/L) are investigated. Both H2 and CH4 productions are increased at high sucrose concentrations. However the optimum H2 and CH4 yields of 163.2 mL-H2/g-sucrose and 211.8 mL-CH4/g-TVS are obtained at 5 g-sucrose/L. At 5 g-sucrose/L addition of Fe2+ increases the H2 yield to 192.5 and 176.2 mLH2/g-sucrose corresponding to 60 and 120 mg-Fe2+/L respectively. Higher removal efficiencies and total energy recovery are measured using the two-stage system than the single-stage reactor.

Hydrogen is the energy carrier for a sustainable future without fossil fuels. As this requires a reliable transportation infrastructure the conversion of existing natural gas (NG) grids is an essential part of the worldwide individual national hydrogen strategies in addition to newly erected pipelines. In view of the known effect of hydrogen embrittlement the compatibility of the materials already in use (typically low-alloy steels in a wide range of strengths and thicknesses) must be investigated. Initial comprehensive studies on the hydrogen compatibility of pipeline materials indicate that these materials can be used to a certain extent. Nevertheless the material compatibility for hydrogen service is currently of great importance. However pipelines require frequent maintenance and repair work. In some cases it is necessary to carry out welding work on pipelines while they are under pressure e.g. the well-known tapping of NG grids. This in-service welding brings additional challenges for hydrogen operations in terms of additional hydrogen absorption during welding and material compatibility. The challenge can be roughly divided into two parts: (1) the possible austenitization of the inner piping material exposed to hydrogen which can lead to additional hydrogen absorption and (2) the welding itself causes an increased temperature range. Both lead to a significantly increased hydrogen solubility in the respective materials compared to room temperature. In that connection the knowledge on hot tapping on hydrogen pipelines is rare so far due to the missing service experiences. Fundamental experimental investigations are required to investigate the possible transferability of the state-of-the-art concepts from NG to hydrogen pipeline grids. This is necessary to ensure that no critical material degradation occurs due to the potentially increased hydrogen uptake. For this reason the paper introduces the state of the art in pipeline hot tapping encompassing current research projects and their individual solution strategies for the problems that may arise for future hydrogen service. Methods of material testing their limitations and possible solutions will be presented and discussed.

High-renewables grids are planned in min but judged in milliseconds; credible studies must therefore resolve both horizons within a single model. Current adequacy tools bypass fast frequency dynamics while detailed simulators lack multi-hour optimization leaving investors without a unified basis for sizing storage shifting demand or upgrading transfers. We present a two-layer Hierarchical Model Predictive Control framework that links 15-min scheduling with 1-s corrective action and apply it to Germany’s four TSO zones under a stringent zero-exchange stress test derived from the NEP 2045 baseline. Batteries vehicleto-grid pumped hydro and power-to-gas technologies are captured through aggregators; a decentralized optimizer pre-positions them while a fast layer refines setpoints as forecasts drift; all are subject to inter-zonal transfer limits. Year-long simulations hold frequency within ±2 mHz for 99.9% of hours and below ±10 mHz during the worst multi-day renewable lull. Batteries absorb sub-second transients electrolyzers smooth surpluses and hydrogen turbines bridge week-long deficits—none of which violate transfer constraints. Because the algebraic core is modular analysts can insert new asset classes or policy rules with minimal code change enabling policy-relevant scenario studies from storage mandates to capacity-upgrade plans. The work elevates predictive control from plantscale demonstrations to system-level planning practice. It unifies adequacy sizing and dynamic-performance evaluation in a single optimization loop delivering an open scalable blueprint for high-renewables assessments. The framework is readily portable to other interconnected grids supporting analyses of storage obligations hydrogen roll-outs and islanding strategies.

To meet decarbonization targets demand for low-emission hydrogen is increasing. A considerable share of supply will come from latecomer countries. We study how latecomer countries and firms participate in the emerging global low-emission hydrogen economy and how industrial policies can help maximize societal benefits. This requires a specific conceptualization of industrial policy: First the latecomer condition calls for specific policy mixes as latecomers typically cannot build on established innovation systems and network externalities and rather need to combine FDI attraction with measures strengthening absorptive capacity and ensuring knowledge transfer from FDI to domestic firms; second low-emission hydrogen is a policy-induced alternative that requires creating entirely new firm ecosystems while competing with lower-cost emission-intensive incumbent technologies. Hence industrial policies need to account for enhanced coordination failure and internalization of environmental costs. We analyze the published national hydrogen strategies of 20 latecomer economies and derive a novel typology differentiating four hydrogen-specific industrial development pathways. For each pathway we assess entry barriers and risks identify the policies suggested in the country strategies and discuss how likely those are to be successful. The novel pathway typology and comparison of associated policy mixes may help policymakers maximize the gains of hydrogen investments.