Applications & Pathways

The widespread adoption of hydrogen-fueled vehicles (HFVs) and the deployment of Hydrogen Refueling Stations (HRS) hinge on the ability to accurately predict system performance and ensure operational reliability. This study proposes a novel predictive framework integrating mathematical modeling state-space analysis and advanced data mining techniques supported by reliability analysis to evaluate the performance of HFVs and their associated refueling infrastructure. Utilizing a public dataset of 500 real-time operational data points key performance indicators are statistically analyzed. A significant negative correlation (r = −0.56) between hydrogen consumption and maximum vehicle range is identified highlighting that improved hydrogen efficiency directly extends travel range. The average maximum range is 555.21 km with a standard deviation of 87.09 km and a median of 563.65 km indicating strong consistency across vehicles. These findings underscore the importance of optimizing fuel efficiency to enhance system sustainability and inform the design and operation of next-generation hydrogen mobility solutions. The proposed approach offers a robust foundation for performance forecasting infrastructure planning and policy development in hydrogen-based transportation systems.

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.

Ocean islands possess abundant renewable energy resources providing favorable conditions for developing offshore clean energy microgrids. However geographical isolation poses significant challenges for direct energy transfer between islands. Recent electrolysis and hydrogen storage technology advancements have created new opportunities for distributed energy utilization in these remote areas. This paper presents a low-carbon economic dispatch strategy designed explicitly for distant oceanic islands incorporating energy self-sufficiency rates and seasonal hydrogen storage (SHS). We propose a power supply model for offshore islands considering hydrogen production from offshore wind power. The proposed model minimizes operational and carbon emission costs while maximizing energy self-sufficiency. It considers the operational constraints of the island’s energy system the offshore transportation network the hydrogen storage infrastructure and the electricityhydrogen-transportation coupling of hydrogen storage (HS) and seasonal hydrogen storage (SHS) services. To optimize the dispatch process this study employs an improved Grey Wolf Optimizer (IGWO) combined with the Differential Evolution method to enhance population diversity and refine the position updating mechanism. Simulation results demonstrate that integrating HS and SHS effectively enhances energy self-sufficiency and reduces carbon emissions. For instance hydrogenation costs decreased by 21.4% after optimization and the peak-valley difference was reduced by 16%. These findings validate the feasibility and effectiveness of the proposed approach.

Most remote and northern communities rely on diesel for their electrical and thermal energy needs. Communities and governments are working toward diesel exit strategies but the role of hydrogen technologies has not been explored. These could serve both electrical and thermal demand reduce emissions and enhance energy security and community ownership. Here we determine the installed capacities costs hydrogen storage needs and water resource requirements of hydrogen microgrids across a large diverse sample of communities. We also compare the cost of hydrogen microgrids to that of diesel microgrids. Our results optimize resource deployment demonstrate how sub-components must operate to serve both demand types and yield insights on storage and resource needs. We find that hydrogen microgrids are cheaper in levelized cost terms than diesel systems in 28 of 37 communities investigated; if wind power capital costs escalate to CAD 20000/kW as recently seen in one project only 3 of the 37 communities net hydrogen microgrids that are cheaper than diesel variants. Hydrogen storage plays a large role in maintaining reliability and reducing cost—both it and water needs are modest. The former can be met with current technologies.

The decarbonization of remote energy systems presents both technical and economic challenges due to their dependance on fossil fuels and the variability of renewable energy sources. This study introduces a Two-Stage Stochastic Programming approach to optimize Hybrid Renewable Energy Systems under uncertainty in renewable energy production. The methodology is applied to the island of Pantelleria aiming to minimize Total Annualized Costs and CO2 emissions using an ε-constraint approach. Results show that within the set of optimized configurations stricter CO2 emissions constraints increase costs due to the need for oversized components to ensure supply reliability. Nevertheless even the zeroemissions scenario offers significant economic benefits compared to the current diesel-based system. Total Annualized Costs are reduced from 15.5 M€ to 8.10 M€ in the deterministic case and to 9.37 M€ in the stochastic one. The additional cost in the stochastic configuration is offset by improved reliability ensuring demand is met under all scenarios. A sensitivity analysis on electricity demand reveals the necessity of further larger components leading to a 27.0% cost increase in a fully renewable scenario with stochastic optimization for a 10% demand increase. These findings highlight the importance of stochastic optimization in designing cost-effective off-grid renewable energy systems.

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.

Propulsion systems in aircraft using reciprocating engines often face the challenge of managing thermal loads effectively. This problem is similar to the utilisation of polymer electrolyte membrane fuel cell systems which despite their high efficiency emit a high proportion of heat when converting chemical energy into electrical energy. Transfer of the rejected heat to the air is efficiently performed by heat exchangers. Since convective heat transfer is physically linked to fluid friction at the heat exchanger walls a pressure loss occurs. In a high-speed flow regime of the aircraft during cruise the integration of heat exchangers combined with a fan stage inside a nacelle (thus forming an impeller configuration) represents a promising approach for the dual benefit of dissipating excess heat and harnessing it for additional thrust generation through the ram jet effect. Striving for enhanced thrust performance of hydrogen electric commercial aircraft this paper presents the results of a parameter study based on a 1D-modelling approach. The focus is placed on the influence of design and operating parameters (ambient conditions fan pressure ratio diffusion ratio airside temperature difference) on performance and sizing of the proposed propulsion system. It is shown that the proposed system performs best at an altitude of 11 km and with increasing freestream Mach number. Furthermore the main challenges related to the combination of a thrust generation system with a heat exchanger in terms of sizing in particularly the required heat exchanger dimensions under different operating conditions are discussed.

The global climate crisis necessitates the urgent implementation of sustainable practices and carbon emission reduction strategies across all sectors. Transport as a major contributor to greenhouse gas emissions requires transitional technologies to bridge the gap between fossil fuel dependency and renewable energy systems. Natural gas recognised as the cleanest fossil-derived fuel with approximately half the CO2 emissions of coal and 75% of oil presents a potential transitional solution through Natural Gas Vehicles (NGVs). This manuscript presents several distinctive contributions that advance the understanding of Natural Gas Vehicles within the contemporary energy transition landscape while synthesising updated emission performance data. Specifically the feasibility and sustainability of NGVs are investigated within the energy transition framework by systematically incorporating recent technological developments and environmental economic and infrastructure considerations in comparison to conventional vehicles (diesel and petrol) and unconventional alternatives (electric and hydrogen-fuelled). The analysis reveals that NGVs can reduce CO2 emissions by approximately 25% compared to petrol vehicles on a well-to-wheel basis with significant reductions in NOx and particulate matter. However these environmental benefits depend heavily on the source and type of natural gas used (CNG or LNG) while economic viability hinges largely on governmental policies and infrastructure development. The findings suggest that NGVs can serve as an effective transitional technology in the transport sector’s sustainability pathway particularly in regions with established natural gas infrastructure but require supportive policy frameworks to overcome implementation barriers.

Green hydrogen offers a sustainable alternative source of fossil fuels to compensate for the increasing energy demand. This study addresses the increasing energy demand and the need for sustainable alternatives to fossil fuels by examining the production of green hydrogen in an existing Egyptian oil refinery. The primary objective is to evaluate the technical economic and environmental outcomes of integrating green hydrogen to increase the refinery’s hydro processing capacity. The methodology involves the use of water electrolysis powered exclusively by renewable electricity from a 60 MW solar installation with a panel surface area of 660000 m². A simulation model of alkaline electrolyzer skids was developed to assess the production of an additional 1260 kg/h of hydrogen representing a 15% increase over the existing Steam Methane Reforming (SMR) capacity. The environmental impact was quantified by calculating the reduction in CO₂ and equivalent emissions while an economic forecasting analysis was conducted to project the production costs of green versus grey hydrogen. The main results indicate that the integration is technically feasible and environmentally beneficial with a significant reduction in the refinery’s carbon footprint. Economically the study projects that by 2028 the production cost of green hydrogen will fall to 1.56 USD/kg H₂ becoming more cost-effective than grey hydrogen at 1.65 USD/kg H₂ largely due to the influence of carbon taxes and credits. This study underscores the transformative potential of green hydrogen in decarbonizing industrial processes offering a viable pathway for refineries to contribute to global climate change mitigation efforts.

The reliability and sustainability of multi-energy networks are increasingly critical in addressing modern energy demands and environmental concerns. Hydrogen-based hybrid energy systems can mitigate the challenges of renewable energy utilization such as intermittency grid stability and energy storage by integrating hydrogen generation and electricity storage from renewable sources such as solar and wind. Therefore this review offers a comprehensive evaluation of the environmental economic and technological aspects of green hydrogen-based hybrid energy systems particularly highlighting improvements in terms of the economics of fuel cell and electrolysis procedures. It also highlights new approaches such as hybrid energy management strategies and power-to-gas (PtG) conversion to enhance the system’s dependability and resilience. Analyzing the role of green hydrogen-based hybrid energy systems in supporting global climate goals and improving energy security underscores their high potential to make a significant contribution to carbon-neutral energy networks and provide policymakers with useful recommendations for developing guidelines. In addition the social aspect of hydrogen systems like energy equity and community engagement towards a hydrogen-based society provides reasons for the continued development of next-generation energy systems.