Publications

In recent years governments have promoted the shift to low-emission transport systems with electric and hydrogen vehicles emerging as key alternatives for greener urban mobility. Evaluating zero- or near-zero tailpipe solutions requires a Lifecycle Assessment (LCA) approach accounting for emissions from energy production components and vehicle manufacturing. Such studies mainly address Greenhouse Gas (GHG) emissions while other pollutants are often overlooked. This study compares the Human Toxicity Potential (HTP) of Battery Electric Vehicles (BEVs) Fuel Cell Vehicles (FCVs) Hydrogen Internal Combustion Engine Vehicles (H2ICEVs) and hybrid H2ICEVs for public transport in the European Union. Current and future scenarios (2024 2030 2050) are examined considering evolving energy mixes and manufacturing impacts. Results underline that BEVs are characterized by the highest HTP in 2024 and that this trend is maintained even in future scenarios. As for hydrogen-based powertrains they show lower HTPs similar among them. This work underlines that current efforts must be intensified especially for BEVs to further limit harmful emissions from the mobility sector.

Hybrid water electrolysis system was designed by using Ruthenium-Tin Oxide (RuSn12.4O2) electrocatalyst as anode material for efficient hydrogen production enhancing energy conversion efficiency. The RuSn12.4O2 Electrocatalyst was synthesized by hydrothermal method and exhibited exceptional activity making it an optimal choice for Iodide oxidation reaction (IOR) and enabling energy-saving hydrogen production. The two-electrode acidic electrolyzer reduced voltage consumption by 0.51 V at 10 mA cm-2 compared to oxygen evolution reaction (OER) at the same current density. This hybrid electrolysis system achieved a remarkable reduction in energy consumption of over 40 % compared to OER process. The Chrono-potentiometric test demonstrated that the RuSn12.4O2 electro-catalyst’s superior stability and low overpotential increase of 70 mV at 10 mAcm-2 . The RuSn12.4O2 electro-catalyst Tafel slope is also a crucial metric for understanding kinetic characteristics in both IOR and OER processes. Thus RuSn12.4O2 electro-catalyst in IOR has a lower Tafel slope (61 mV dec-1) than that in OER according to the Tafel slopes determined from linear sweep voltammetry (LSV) curves. Additionally at various potentials the electro-catalyst's activity toward IOR to produce hydrogen demonstrated exceptional performance in this electrolysis system without causing any catalyst degradation.

Energy in the microwave spectrum is increasingly applied in clean energy technologies. This review discusses recent innovations using microwave fields in hydrogen production and synthesis of new battery materials highlighting the unique properties of microwave heating. Key innovations include microwave-assisted hydrogen generation from water hydrocarbons and ammonia and the synthesis of high-performance anode and cathode materials. Microwave-assisted catalytic water splitting using Gd-doped ceria achieves efficient hydrogen production below 250°C. For hydrocarbons advanced microwave-active catalysts Fe–Ni alloys and ruthenium nanoparticles enable high conversion rates and hydrogen yields. In ammonia synthesis microwaves reduce the energy demands of the Haber–Bosch process and enhance hydrogen production efficiency using catalysts such as ruthenium and Co2Mo3N. In battery technology microwave-assisted synthesis of cathode materials like LiFePO4 and LiNi0.5Mn1.5O4 yields high-purity materials with superior electrochemical performance. Developing nanostructured and composite materials including graphene-based anodes significantly improves battery capacities and cycling stability. The ability of microwave technology to provide rapid selective heating and enhance reaction rates offers significant advancements in clean energy technologies. Ongoing research continues to bridge theoretical understanding and practical applications driving further innovations in this field. This review aims to highlight recent advances in clean energy technologies based upon the novel use of microwave energy. The potential impact of these emerging applications is now being fully understood in areas that are critical to achieving net zero and can contribute to the decarbonization of key sectors. Notable in this landscape are the sectors of hydrogen fuel and battery technologies. This review examines the role of microwaves in these areas.

Heavy-duty fuel cell trucks are a promising approach to reduce the CO2 emissions of logistic fleets. Due to their higher powertrain energy density in comparison to battery-electric trucks they are especially suited for long-haul applications while transporting high payloads. Despite these great advantages the fleet integration of such vehicles is made difficult due to high costs and limited performance in thermally critical environmental conditions. These challenges are addressed in the European Union (EU) funded project ESCALATE which aims to demonstrate high-efficiency zero-emission heavy-duty vehicle (zHDV) powertrains that provide a range of 800 km without refueling or recharging. Powertrain components and their corresponding thermal components account for a large part of the production costs. For vehicle users higher costs are only acceptable if a significantly higher benefit can be achieved. Therefore it is important to size these components for the actual vehicle mission to avoid oversizing. In this paper an optimization method which determines the optimum component sizes for a given mission scenario under consideration of multiple criteria (e.g. costs performance and range) is presented.

This research evaluates four hydrogen (H2) production technologies via water electrolysis (WE): alkaline water electrolysis (AWE) proton exchange membrane electrolysis (PEME) anion exchange membrane electrolysis (AEME) and solid oxide electrolysis (SOE). Two scoring and ranking methods the MACBETH method and the Pugh decision matrix are utilized for this evaluation. The scoring process employs nine decision criteria: capital expenditure (CAPEX) operating expenditure (OPEX) operating efficiency (SOE) startup time (SuT) environmental impact (EI) technology readiness level (TRL) maintenance requirements (MRs) supply chain challenges (SCCs) and levelized cost of H2 (LCOH). The MACBETH method involves pairwise technology comparisons for each decision criterion using seven qualitative judgment categories which are converted into quantitative scores via M-MACBETH software (Version 3.2.0). The Pugh decision matrix benchmarks WE technologies using a baseline technology—SMR with CCS—and a three-point scoring scale (0 for the baseline +1 for better −1 for worse). Results from both methods indicate AWE as the leading H2 production technology which is followed by AEME PEME and SOE. AWE excels due to its lowest CAPEX and OPEX highest TRL and optimal operational efficiency (at ≈7 bars of pressure) which minimizes LCOH. AEME demonstrates balanced performance across the criteria. While PEME shows advantages in some areas it requires improvements in others. SOE has the most areas needing enhancement. These insights can direct future R&D efforts toward the most promising H2 production technologies to achieve the net-zero goal.

One of the key elements in the advancement of hydrogen (H2) and fuel cell technologies is to store H2 effectively for use in various industries such as transportation defense portable electronics and energy. Because of its highest energy density availability and environmental and health benefits H2 stands as a promising future energy carrier. Currently enterprises are searching for a solution for energy distribution management and H2 gas storage. Thus there is a need to develop an innovative solution to H2 storage that might be considered for later use in aviation applications. This study aims to synthesize an electrospun nanocomposite fiber (NCF) for an H2 storage application and to understand the absorption kinetics of the resultant highly porous NCF mats. This study incorporates functional NCFs with H2-sensitive inclusions to increase the storage capacity and absorption/desorption kinetics of H2 gas at lower temperatures and pressures. Here the electrospinning technique is utilized to produce NCFs with various nanoscale metal hydrides (MHs) and conductive particles which support enhancing H2 storage capacity and kinetics. These NCFs enable controlled H2 storage and improve thermal properties. Selected polymeric materials for H2 storage that have been investigated are polyacrylonitrile (PAN) polymethyl methacrylate (PMMA) and sulfonated polyether ether ketone (SPEEK) in combination with MHs and multiwalled carbon nanotubes (MWCNTs). On testing it was observed that H2 capacity with SPEEK which includes 4 wt% MWCNTs and 4 wt% MH MmNi4.5Fe0.5 shows significant H2 uptake compared to a PAN/PMMA polymer.

Achieving climate neutrality goals is inseparable from the sustainable development of modern cities. Municipal wastewater treatment plants (WWTP) are among the starting points when moving cities to Net-zero Greenhouse Gas (GHG) emissions and climate neutrality. This study focuses on the analysis of the integration of green hydrogen (H2) and biomethane technologies in WWTPs and on the impact of this integration on WWTPs’ energy neutrality. This study treats WWTP as an integrated energy system with certain inputs and outputs. Currently such systems in most cases have a significantly negative energy balance and in addition fossil fuel energy sources are used. Key findings highlight that the integration of green hydrogen production in WWTPs and the efficient utilization of electrolysis by-products can make such energy systems neutral or even positive. This study provides an analysis of the main technical presumptions for the successful integration of green hydrogen and biomethane production processes in WWTP. Furthermore a case study of a real wastewater treatment plant is presented.

As one of the most promising renewable green energies hydrogen power is a popularly accepted option to drive automobiles. Commercial application of fuel cell vehicles has been started since 2015. More and more hydrogen safety concerns have been considered for years. Tunnels are an important part of traffic infrastructure with a mostly confined feature. A hydrogen leak followed possibly by a hydrogen fire is a potential accident scenario which can be triggered trivially by a car accident while hydrogen-powered vehicles operate in a tunnel. Water spray is recommended traditionally as a mitigation measure against tunnel fires. The interaction between water spray and hydrogen fire is studied by way of numerical simulations. By using the computer program of Fire Dynamics Simulator (FDS) tunnel fires of released hydrogen in different scales are simulated coupled with water droplet injections featured in different droplet sizes or varying mass flow rates. The cooling effect of spray on hot gases of hydrogen fires is apparently observed in the simulations. However in some circumstances the turbulence intensified by the water injection can prompt hydrogen combustion which is a negative side effect of the spray.

Research on and the demand for hydrogen-powered vehicles have grown significantly over the past two decades as a solution for sustainable transportation. Bibliometric analysis helps to assess research trends key contributions and the impact of studies focused on the safety and reliability of hydrogen-powered vehicles. This study provides a novel methodology for bibliometric analysis that systematically evaluates the global research landscape on hydrogen-powered vehicle reliability using Scopus-indexed publication data (1965 to 2024). Eighteen key parameters were identified for this study that are often used by researchers for the bibliometric analysis of hydrogen-related studies. Data analytics VOSviewer-based visualization and research impact indicators were integrated to comprehensively assess publication trends key contributors and citation networks. The analysis revealed that hydrogen-powered vehicle reliability research has experienced significant growth over the past two decades with leading contributions from high-impact journals renowned institutions and influential authors. The present study emphasizes the significance of greater funding as well as open-access distribution. Furthermore while major worldwide institutions have significant institutional relationships there are gaps in real-world hydrogen infrastructure evaluations large-scale experimental validation and policy-driven research.

Hydrogen (H2) used as feedstock (i.e. as raw material) in chemicals refineries and steel is currently produced from fossil fuels thus leading to significant carbon dioxide (CO2) emissions. As these hard-to-abate sectors have limited electrification alternatives H2 produced by electrolysis offers a potential option for decarbonising them. Existing modelling analyses to date provide limited insights due to their predominant use of sector-specific static non-recursive and non-open models. This paper advances research by presenting a dynamic recursive open-access energy model using System Dynamics to study long-term systemic and environmental impacts of transitioning from fossil-based methods to electrolytic H2 production for industrial feedstock. The regional model adopts a bottom-up approach and is applied to the EU across five innovative decarbonisation scenarios including varying technological transition speeds and a paradigm-shift scenario (Degrowth). Our results indicate that assuming continued H2 demand trends and large-scale electrolytic H2 deployment by 2030 grid decarbonisation in the EU must accelerate to ensure green H2 for industrial feedstock emits less CO2 than fossil fuel methods doubling the current pace. Otherwise electrolytic H2 won’t offer clear CO2 reduction benefits until 2040. The most effective CO2 emission mitigation occurs in growth-oriented ambitious decarbonisation (− 91 %) and Degrowth (− 97 %) scenarios. From a sectoral perspective H2 use in steel industry achieves significantly greater decarbonisation (− 97 %). However meeting electricity demand for electrolytic H2 (700–1180 TWh in 2050 for 14–22.5 Mtons) in growth-oriented scenarios would require 25 %–42 % of the EU’s current electricity generation exceeding current renewable capacity and placing significant pressure on future power system development.