Publications

Hydrogen energy generation faces challenges in efficiency and economic viability due to reliance on scarce noble metal catalysts. This study aimed to develop platinum-doped nickel-iron metal-organic framework (Pt-NiFe-MOF) catalysts with controlled metal ratios and pore architecture for enhanced water electrolysis. The NiFe-MOF framework was first synthesized via a solvothermal method which was then subjected to post-synthetic modification to introduce controlled platinum loadings (0.5- 2.0 wt%). The pore structure was tuned using a mixed-linker strategy (H₄DOBDC ratios 1:0 to 1:1). Catalysts were characterized using PXRD HRTEM BET XPS and ICP-OES techniques. Electrochemical performance was analyzed in 1.0 M KOH. A custom-designed integrated electrolysis system at 75 °C assessed practical performance. The Pt-NiFe-MOF-1.0 catalyst with H₄DOBDC ratio of 1:0.5 achieved remarkable effectiveness requiring overpotentials of only 253 mV for OER and 58 mV for HER when operating at 10 mA/cm². This catalyst featured an optimal pore diameter of 4.2 nm and surface area of 1325 m²/g. DFT calculations revealed platinum incorporation created synergistic effects by modifying hydrogen binding energies. Furthermore DFT calculations and XPS analysis revealed that the role of platinum in the OER is not direct catalysis but rather a powerful electronic modulation effect; Pt dopants withdraw electron density from adjacent Ni and Fe centers promoting the formation of higher-valent Ni³⁺/Fe³⁺ species that are intrinsically more active and lowering the energy barrier for the rate-determining O-O bond formation step. The integrated system achieved 1.62V at 100 mA/cm² with 75.8% energy efficiency maintaining stability for 200 h with 15–30 times lower precious metal loading than conventional systems. Strategic incorporation of low platinum concentrations within optimized NiFe-MOF structures significantly enhances water electrolysis performance while maintaining economic viability advancing development of industrial-scale hydrogen generation systems.

The EU targets 10 Mt of green hydrogen production by 2030 but has not committed to targets for 2040. Green hydrogen competes with carbon capture and storage biomass and imports as well as direct electrification in reaching emissions reductions; earlier studies have demonstrated the great uncertainty in future costoptimal development of green hydrogen. In spite of this we show that Europe risks little by setting green hydrogen production targets at around 25 Mt by 2040. Employing an extensive scenario analysis combined with novel near-optimal techniques we find that this target results in systems that are within 10% of cost-optimal in all considered scenarios with current-day biomass availability and baseline transportation electrification. Setting concrete targets is important in order to resolve significant uncertainty that hampers investments. Targeting green hydrogen reduces the dependence on carbon capture and storage and green fuel imports making for a more robust European climate strategy.

The escalating global demand for primary energy—still predominantly met by conventional carbon-based fuels—has led to increased atmospheric pollution. This underscores the urgent need for alternative energy strategies capable of reducing carbon emissions while meeting global energy requirements. Hydrogen as a clean combustible fuel offers a promising alternative to hydrocarbons producing neither soot CO2 nor unburned hydrocarbons. Although nitrogen oxides (NOx) are the primary combustion by-products their formation can be mitigated by controlling flame temperature. This study investigates the viability of hydrogen as a clean energy vector by simulating an unsteady turbulent non-premixed hydrogen jet flame interacting with an air co-flow. The numerical simulations employ the Unsteady Reynolds-Averaged Navier–Stokes (URANS) framework for efficient and accurate prediction of transient flow behavior. Turbulence is modeled using the Shear Stress Transport (SST k-ω) model which enhances accuracy in high Reynolds number reactive flows. The combustion process is described using a presumed Probability Density Function (PDF) model allowing for a statistical representation of turbulent mixing and chemical reaction. The simulation results are validated by comparison with experimental temperature and mixture fraction data demonstrating the reliability and predictive capability of the proposed numerical approach.

This study presents a novel multi-objective optimization framework supporting nations sustainability 2030–2040 visions by enhancing renewable energy integration green hydrogen production and emission reduction. The framework evaluates a range of energy storage technologies including battery pumped hydro compressed air energy storage and hybrid configurations under realistic system constraints using the IEEE 9-bus test system. Results show that without storage renewable penetration is limited to 28.65% with 1538 tCO2/day emissions whereas integrating pumped hydro with battery (PHB) enables 40% penetration cuts emissions by 40.5% and reduces total system cost to 570 k$/day (84% of the baseline cost). The framework’s scalability is confirmed via simulations on IEEE 30- 39- 57- and 118-bus systems with execution times ranging from 118.8 to 561.5 s using the HiGHS solver on a constrained Google Colab environment. These findings highlight PHB as the most cost-effective and sustainable storage solution for large-scale renewable integration.

Hydrogen recognized as a critical energy source requires green production methods such as proton exchange membrane water electrolysis (PEMWE) powered by renewable energy. This is a key step toward sustainable development with economic analysis playing an essential role. Life cycle costing (LCC) is commonly used to evaluate economic feasibility but traditional LCC analyses often provide a single cost outcome which limits their applicability across diverse regional contexts. To address these challenges a Python-based tool is developed in this paper integrating a bottom-up approach with net present value (NPV) calculations and Monte Carlo simulations. The tool allows users to manage uncertainty by intervening in the input data producing a range of outcomes rather than a single deterministic result thus offering greater flexibility in decision-making. Applying the tool to a 5 MW PEMWE plant in Germany the total cost of ownership (TCO) is estimated to range between €52 million and €82.5 million with hydrogen production costs between 5.5 and 11.4 €/kg H2. There is a 95% probability that actual costs fall within this range. Sensitivity analysis reveals that energy prices are the key contributors to LCC accounting for 95% of the variance in LCC while iridium membrane materials and power electronics contribute to 75% of the variation in construction-phase costs. These findings underscore the importance of renewable energy integration and circular economy strategies in reducing LCC.

In this study a liquid hydrogen (LH2) safety valve evaluation device was developed to enable safe and stable performance testing of pressure safety valves (PSVs) under realistic cryogenic and high-pressure conditions. The device was designed for flexible use by mounting all components on a mobile frame equipped with wheels and the pressurization rate inside the vessel was controlled through a boil-off gas (BOG) generator. Two experiments were conducted to investigate the effect of LH2 production rate on PSV operation. When the production of LH2 increased by about 2.4 times the number of PSV operations rose from 15 to 20 and the operating pressure range shifted slightly upward from 10.68~12.53 bar to 10.68~13.2 bar while remaining within the instrument’s error margin. These results indicate that repeated valve cycling and increased hydrogen production contribute to gradual changes in PSV operating characteristics. Additionally the minimum temperature experienced by the PSV decreased with repeated operations reaching approximately 77.9 K. The developed evaluation system provides an effective platform for analyzing PSV performance under realistic LH2 production and storage conditions.

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

The global aviation sector is essential for connecting people cultures and economies but it significantly contributes to greenhouse gases (GHG) exacerbating environmental concerns. This systematic literature review examines the transformation of waste into Sustainable Aviation Fuels (SAF) highlighting their potential to reduce the aviation industry’s carbon footprint. The review explores waste-to-fuel technologies such as gasification pyrolysis liquefaction and Fischer-Tropsch synthesis mainly focusing on the eight ASTM-certified bio-jet fuel production pathways demonstrating the highest readiness levels. The study covers methodologies case studies and optimszation studies identifying significant trends advancements and gaps in the literature to develop SAF from waste. Key findings reveal that some processes can significantly reduce CO2 emissions and improve sustainability but challenges persist. Despite the potential of thermochemical pathways combined with oil hydro-processing and their technological readiness the pathway’s production costs remain high and robust regulatory support is needed to scale up SAF production. Integrating pathways in a hybrid format could further offer a synergistic approach to developing SAF that combine high performance with economic and environmental sustainability. Future research should address these gaps enhance energy and economic efficiencies and explore innovative feedstocks and catalytic processes. The review provides valuable insights for environmentalists industry stakeholders engineers and policymakers supporting efforts to achieve sustainable aviation and global environmental goals.

Importing renewable energy to Europe may offer many potential benefits including reduced energy costs lower pressure on infrastructure development and less land use within Europe. However open questions remain: on the achievable cost reductions how much should be imported whether the energy vector should be electricity hydrogen or derivatives like ammonia or steel and their impact on Europe’s infrastructure needs. This study integrates a global energy supply chain model with a European energy system model to explore net-zero emission scenarios with varying import volumes costs and vectors. We find system cost reductions of 1-10% within import cost variations of ± 20% with diminishing returns for larger import volumes and a preference for methanol steel and hydrogen imports. Keeping some domestic power-to-X production is beneficial for integrating variable renewables leveraging local carbon sources and power-to-X waste heat. Our findings highlight the need for coordinating import strategies with infrastructure policy and reveal maneuvering space for incorporating non-cost decision factors.

Developing new injection systems and combustion chambers for hydrogen is a central topic for the new generation of engines. In this effort simulations take a central role but methods developed for conventional hydrocarbons (methane kerosene) must be revisited for hydrogen. Validation then becomes an essential part and clean well documented experiments are needed to guaranty that computational fluid dynamics solvers are as predictive and accurate as expected. In this framework the HYLON case is a swirled hydrogen/air burner used by multiple groups worldwide to validate simulation methods for hydrogen combustion in configurations close to gas turbine burners with experimental data available through the TNF web site. The present study compares recent Raman spectroscopy and Particle Image Velocimetry measurements and Large Eddy Simulations (LES). The LES results are evaluated against a dataset comprising mean and RMS measurements of H2 N2 O2 H2O molar fractions temperature and velocity fields offering new insights into flame stabilization mechanisms. The simulations incorporate conjugate heat transfer to predict the combustor wall temperatures and are conducted for two atmospheric-pressure operating conditions each representing distinct combustion regimes diffusion and partially premixed. Novelty and significance statement Data on confined hydrogen flames in burner similar as industrial ones are limited. This work aims to fill this gap by performing multiple and simultaneous diagnostics on the swirled hydrogen-air flame called HYLON. For the first time in such a swirled configuration mean and RMS fields of temperature main species and velocities are compared to LES allowing new insight into the potential and limits of the models as well as the physics of these flames. These experimental results will be made available on TNF as over 30 research groups worldwide have expressed interest in using them.