Italy

The present paper offers a thorough examination of the safety measures enforced at hydrogen filling stations emphasizing their crucial significance in the wider endeavor to advocate for hydrogen as a sustainable and reliable substitute for conventional fuels. The analysis reveals a wide range of crucial safety aspects in hydrogen refueling stations including regulated hydrogen dispensing leak detection accurate hydrogen flow measurement emergency shutdown systems fire-suppression mechanisms hydrogen distribution and pressure management and appropriate hydrogen storage and cooling for secure refueling operations. The paper therefore explores several aspects including the sophisticated architecture of hydrogen dispensers reliable leak-detection systems emergency shut-off mechanisms and the implementation of fire-suppression tactics. Furthermore it emphasizes that the safety and effectiveness of hydrogen filling stations are closely connected to the accuracy in the creation and upkeep of hydrogen dispensers. It highlights the need for materials and systems that can endure severe circumstances of elevated pressure and temperature while maintaining safety. The use of sophisticated leak-detection technology is crucial for rapidly detecting and reducing possible threats therefore improving the overall safety of these facilities. Moreover the research elucidates the complexities of emergency shut-off systems and fire-suppression tactics. These components are crucial not just for promptly managing hazards but also for maintaining the station’s structural soundness in unanticipated circumstances. In addition the study provides observations about recent technical progress in the industry. These advances effectively tackle current safety obstacles and provide the foundation for future breakthroughs in hydrogen fueling infrastructure. The integration of cutting-edge technology and materials together with the development of upgraded safety measures suggests a positive trajectory towards improved efficiency dependability and safety in hydrogen refueling stations.

Hydrogen production and storage in hybrid systems is a promising solution for sustainable energy transition decoupling the energy generation from its end use and boosting the deployment of renewable energy. Nonetheless the optimal and cost-effective design of hybrid hydrogen-based systems is crucial to tackle existing limitations in diffusion of these systems. The present study explores net-zero energy management via a multi-objective optimization algorithm for an outdoor test facility equipped with a hydrogen-based hybrid energy production system. Aimed at enabling efficient integration of hydrogen fuel cell system the proposed solution attempts to maximize the renewable factor (RF) and carbon mitigation in the hybrid system as well as to minimize the grid dependency and the life cycle cost (LCC) of the system. In this context the techno-enviroeconomic optimization of the hybrid system is conducted by employing a statistical approach to identify optimal design variables and conflictive objective functions. To examine interactions in components of the hybrid system a series of dynamic simulations are carried out by developing a TRNSYS code coupled with the OpenStudio/EnergyPlus plugin. The obtained results indicate a striking disparity in the monthly RF values as well as the hydrogen production rate and therefore in the level of grid dependency. It is shown that the difference in LCC between optimization scenarios suggested by design of experiments could reach $15780 corresponding to 57% of the mean initial cost. The LCOE value yielded for optimum scenarios varies between 0.389 and 0.537 $/kWh. The scenario with net-zero target demonstrates the lowest LCOE value and the highest carbon mitigation i.e. 828 kg CO2/yr with respect to the grid supply case. However the LCC in this scenario exceeds $57370 which is the highest among all optimum scenarios. Furthermore it was revealed that the lowest RF in optimal scenarios is equal to 66.2% and belongs to the most economical solution.

This study presents and analyses three plant configurations of the Ocean Thermal Energy Conversion (OTEC) technology. All the solutions are based on using the OTEC system to obtain hydrogen through an electrolyzer. The hydrogen is then compressed and stored. In the first and second layouts a Rankine cycle with ammonia and a mixture of water and ethanol is utilised respectively; in the third layout a Kalina cycle is considered. In each configuration the OTEC cycle is coupled with a polymer electrolyte membrane (PEM) electrolyzer and the compression and storage system. The water entering the electrolyzer is pre-heated to 80 ◦C by a solar collector. Energy exergy and exergo-economic studies were conducted to evaluate the cost of producing compressing and storing hydrogen. A parametric analysis examining the main design constraints was performed based on the temperature range of the condenser the mass flow ratio of hot and cold resource flows and the mass fraction. The maximum value of the overall exergy efficiency calculated is equal to 93.5% for the Kalina cycle and 0.524 €/kWh is the minimum cost of hydrogen production achieved. The results were compared with typical data from other hydrogen production systems.

Hydrogen mobility is a powerful strategy to fight climate change promoting the decarbonization of the transportation sector. However the higher flammability of hydrogen in comparison with traditional fuels raises issues concerning the safety of hydrogen-powered vehicles in particular when urban mobility in crowded areas is concerned. In the present study a comparative analysis of alternative hydrogen storage concepts for buses is carried out. A specific inherent safety assessment methodology providing a hazard footprint of alternative hydrogen storage technologies was developed. The approach provides a set of ex-ante safety performance indicators and integrates a sensitivity analysis performed by a Monte Carlo method. Integral models for consequence analysis and a set of baseline frequencies are used to provide a preliminary identification of the worstcase credible fire and explosion scenarios and to rank the inherent safety of alternative concepts. Cryocompressed storage in the supercritical phase resulted as the more hazardous storage concept while cryogenic storage in the liquid phase at ambient pressure scored the highest safety performance. The results obtained support risk-informed decision-making in the shift towards the promotion of sustainable mobility in urban areas.

In the last few decades the problem of pollution resulting from human activities has pushed research toward zero or net-zero carbon solutions for transportation. The main objective of this paper is to perform a preliminary performance assessment of the use of hydrogen in conventional turbine engines for aeronautical applications. A 0-D dynamic model of the Allison 250 C-18 turboshaft engine was designed and validated using conventional aviation fuel (kerosene Jet A-1). A dedicated experimental campaign covering the whole engine operating range was conducted to obtain the thermodynamic data for the main engine components: the compressor lateral ducts combustion chamber high- and low-pressure turbines and exhaust nozzle. A theoretical chemical combustion model based on the NASA-CEA database was used to account for the energy conversion process in the combustor and to obtain quantitative feedback from the model in terms of fuel consumption. Once the engine and the turbomachinery of the engine were characterized the work focused on designing a 0-D dynamic engine model based on the engine’s characteristics and the experimental data using the MATLAB/Simulink environment which is capable of replicating the real engine behavior. Then the 0-D dynamic model was validated by the acquired data and used to predict the engine’s performance with a different throttle profile (close to realistic request profiles during flight). Finally the 0-D dynamic engine model was used to predict the performance of the engine using hydrogen as the input of the theoretical combustion model. The outputs of simulations running conventional kerosene Jet A-1 and hydrogen using different throttle profiles were compared showing up to a 64% reduction in fuel mass flow rate and a 3% increase in thermal efficiency using hydrogen in flight-like conditions. The results confirm the potential of hydrogen as a suitable alternative fuel for small turbine engines and aircraft.

The growing demand for air travel in the commercial sector leads to an increase in global emissions whose mitigation entails transitioning from the current fossil-fuel based generation of aircrafts to a cleaner one within a short timeframe. The use of hydrogen and fuel cells has the potential to reach zero emissions in the aerospace sector provided that required innovation and research efforts are substantially accomplished. Development programs investments and new regulations are needed for this technology to be safe and economical. In this context it makes sense to develop a model-based preliminary design methodology for a hybrid regional aircraft assisted by a battery hybridized fuel cell powertrain. The technological assumptions underlying the study refer to both current and expected data for 2035. The major contribution of the proposed methodology is to provide a mathematical tool that considers the interactions between the choice of components in terms of installed power and energy management. This simultaneous study is done because of the availability of versatile control maps. The tool was then deployed to define current and future technological scenarios for fuel cell battery and hydrogen storage systems by quickly adapting control strategies to different sizing criteria and technical specifications. In this way it is possible to facilitate the estimation of the impact of different sizing criteria and technological features at the aircraft level on the onboard electrical system the management of in-flight power the propulsion methods the impact of the masses on consumption and operational characteristics in a typical flight mission. The proposed combination of advanced sizing and energy management strategies allowed meeting mass and volume constraints with state-of-the-art PEM fuel cell and Li-ion battery specifications. Such a solution corresponds to a high degree of hybridization between the fuel cell system and battery pack (i.e. 300 kW and 750 kWh) whereas projected 2035 specs were demonstrated to help reduce mass and volume by 23 % and 40 % respectively.

Hydrogen is on the rise as a substitute for fossil fuel in the energy sector. While this substitution does not happen dramatically the steady increase in hydrogen related research might be a good indicator of such desire. As it stands there are issues regarding its safe handling and use; consequently the health and safety subsectors observe the situation conspicuously. As we yet to know the behavior of hydrogen in critical situations uncertainties make these tasks prone to emerging risks. Thus hydrogen safety falls under emerging risk studies. Conventional perspective on safety especially regarding the flammable material focuses on calculating the hypothetical risks of failures in system. Resilience Engineering has another perspective as it focuses on normal operations offering new perspectives to tackle emerging risks from a new angle. Born from the heart of Resilience Engineering the Functional Resonance Analysis Method (FRAM) captures sociotechnical systems’ essence in a tangible way. In this study FRAM has been used to model a series of experiments done on hydrogen management to analyze its jet fire. FRAM is used to test whether the method could be suitable to model a system in which emerging risks are present. It is the conclusion of this study that FRAM seems promising in raising risk awareness especially when available data is limited.

In response to the European Union’s initiative toward achieving carbon neutrality the utilization of water electrolysis for hydrogen production has emerged as a promising avenue for decarbonizing current energy systems. Among the various approaches Solid Oxide Electrolysis Cell (SOEC) presents an attractive solution especially due to its potential to utilize impure water sources. This study focuses on modeling a SOEC supplied with four distinct streams of treated municipal wastewaters using the Aspen Plus software. Through the simulation analysis it was determined that two of the wastewater streams could be effectively evaporated and treated within the cell without generating waste liquids containing excessive pollutant concentrations. Specifically by evaporating 27% of the first current and 10% of the second it was estimated that 26.2 kg/m3 and 9.7 kg/m3 of green hydrogen could be produced respectively. Considering the EU’s target for Italy is to have 5 GW of installed power capacity by 2030 and the mass flowrate of the analyzed wastewater streams this hydrogen production could meet anywhere from 0.4% to 20% of Italy’s projected electricity demand.

In the framework of the “Multidisciplinary Optimization and Regulations for Low-boom and Environmentally Sustainable Supersonic aviation” project pursued by a consortium of European government and academic institutions coordinated by Politecnico di Torino under the European Commission Horizon 2020 financial support the Italian Aerospace Research Centre is computationally investigating the high-pressure hydrogen/air kinetic combustion in the operative conditions typically encountered in supersonic aeronautic ramjet engines. This task is being carried out starting from the zero-dimensional and one-dimensional chemical kinetic assessment of the complex and strongly pressure-sensitive ignition behavior and flame propagation characteristics of hydrogen combustion through the validation against experimental shock tube and laminar flame speed measurements. The 0D results indicate that the kinetic mechanism by Politecnico di Milano and the scheme formulated by Kéromnès et al. provide the best matching with the experimental ignition delay time measurements carried out in high-pressure shock tube strongly argon-diluted reaction conditions. Otherwise the best behavior in terms of laminar flame propagation is achieved by the Mueller scheme while the other investigated kinetic mechanisms fail to predict the flame speeds at elevated pressures. This confirms the non-linear and intensive pressure-sensitive behavior of hydrogen combustion especially in the critical high-pressure and low-temperature region which is hard to be described by a single all-encompassing chemical model.

This paper investigates the economic competitiveness of hydrogen-powered trucks. It reviews the growing number of papers that provide an estimate of the total cost of ownership (TCO) of hydrogen-powered trucks relative to their diesel equivalents. It examines the methodology applied the variables considered the data used for estimation and the results obtained. All reviewed studies conclude that hydrogen-powered trucks are not currently cost-competitive while they might become competitive after 2030. The conclusion holds across truck types and sizes hydrogen pathways mission profiles and countries. However we find that there is still a huge area of uncertainty regarding the purchase price of hydrogen-powered trucks and the cost of hydrogen which hampers the reliability of the results obtained. Various areas of methodological improvements are suggested.

The aim of this study is to investigate the long-term planning of the Italian power sector from 2021 to 2050. The key role of photovoltaic and wind technologies in combination with power-to-power systems based on hydrogen and batteries is investigated. An updated version of the OSeMOSYS tool is used which employs a clustering method for the representation of time-varying input data. First the potential of variable renewable energy sources (VRES) is assessed. A sensitivity analysis is also performed on the temporal resolution of the model to determine an adequate trade-off between the computation time and the accuracy of the results. Then a technoeconomic optimization scenario is carried out resulting in a total net present cost of about 233.7 B€. A high penetration of VRES technologies is foreseen by 2050 with a total VRES installed capacity of 272.9 GW (mainly photovoltaic and onshore wind). Batteries are found to be the preferable energy storage solution in the first part of the energy transition while the hydrogen storage starts to be convenient from about the year 2040. Indeed the role of hydrogen storage becomes fundamental as the VRES penetration increases thanks to its cost-effective long-term storage capability. By 2050 74.6 % of electricity generation will be based on VRES which will also enable a significant reduction in CO2 emissions of about 87 %.

The global momentum towards hydrogen has led to various initiatives aimed at harnessing hydrogen’s potential. In particular low-carbon hydrogen is recognized for its crucial role in reducing greenhouse gas emissions across hard-to-abate sectors such as steel cement and heavy-duty transport. This study focuses on the presentation of all hydrogen-related financing initiatives in Italy providing a comprehensive overview of the various activities and their geographical locations. The examined funding comes from the National Recovery and Resilience Plan (PNRR) from projects directly funded through the Important Projects of Common European Interest (IPCEI) and from several initiatives supported by private companies or other funding sources (hydrogen valleys). Specific calls for proposals within the PNRR initiative outline the allocation of funds focusing on hydrogen production in brownfield areas (52 expected hydrogen production plants by 2026) hydrogen use in hard-to-abate sectors and the establishment of hydrogen refuelling stations for both road (48 refuelling stations by 2026) and railway transport (10 hydrogen-based railway lines). A detailed description of the funded initiatives (150 in total) is presented encompassing their geographical location typology and size (when available) as well as the funding they have received. This overview sheds light on regions prioritising decarbonisation efforts in heavy-duty transport especially along cross-border commercial routes as evident in northern Italy. Conversely some regions concentrate more on local transport typically buses or on the industrial sector primarily steel and chemical industries. Additionally the study presents initiatives aimed at strengthening the national manufacturing capacity for hydrogenrelated technologies alongside new regulatory and incentive schemes for hydrogen. The ultimate goal of this analysis is to foster connections among existing and planned projects stimulate new initiatives along the entire hydrogen value chain raise an awareness of hydrogen among stakeholders and promote cooperation and international competitiveness.

This paper introduces a general criterion for the optimal design and operation of hydrogen storage tanks. Specifically the proposed procedure identifies the optimal delivery schedule that minimizes the capacity of material storage systems. Indeed many manufacturing processes need some buffer storage to administer mass flows appropriately according to the operating needs (one class above all: Power-to-X processes) and have one of their highest expenditures right in those tanks when proving not sufficiently flexible. Hence the novelty of the proposed method lies in a rigorous mathematical formulation that converts arbitrarily fluctuating inlet streams into optimally fluctuating outlet streams that minimize the storage volume and comply with different operating requirements. The criterion is validated by considering the techno-economic assessment of a chemical plant featuring a dedicated green hydrogen production facility that feeds the process. Specifically the required capacity of the “Flexible” hydrogen buffer storage which connects the green hydrogen generation system to the conversion process significantly decreases by 91.31%–99.31% (depending on the flexibility ranges enabled by the downstream conversion process) compared to the “Rigid” storage alternative based on a constant outlet mass flow withdrawal coinciding with the hydrogen consumption rate at nominal operating conditions. Correspondingly the resulting levelized cost of hydrogen benefits accordingly ranging from 4.19 to 6.03 USD/kg (California 2023).

Financing sizing operating or upgrading a hydrogen refueling station (HRS) is challenging and may be complex much more so in today's rapidly changing and growing hydrogen industry. There is a significant information gap regarding experimental hydrogen station activities. A high-level perspective on such data and information may facilitate the transition between present and future HRS operations. To address the need for such high-level perspective this paper presents a comprehensive data set on the performance of the California State University Los Angeles Hydrogen Research and Fueling Facility based on multi-year operational data. The analysis of over 4500 refueling events and over 8800 kg of hydrogen dispensed as well as the operation of the facility electrolyzer and of both storage and refueling compressors from 2016 to 2020 reveals a comprehensive picture of HRS energy performance and the identification of useful key performance indicators. In 2016 the station's energy efficiency was 25% but in 2017 and the first three quarters of 2018 it dropped to 15%. Station-specific energy consumption increased during these quarters. The 2020 first quarter energy consumption was between 70 and 80 kWh/kg. At this time the energy efficiency of the station reached 40%.<br/>This research is based on an unprecedented and unique dataset of an HRS operating under real-world conditions with an approach that can be informative for modeling the performance of other stations providing a dataset that HRS designers operators and investors may utilize to make data-driven choices regarding HRS components and their specs and size as well as operating strategies.

This study addresses the challenge of decarbonizing highly energy-intensive Industrial Port Areas (IPA) focusing on emissions from various sources like ship traffic warehouses buildings cargo handling equipment and hardto-abate industry typically hosted in port areas. The analysis and proposal of technological solutions and their optimal integration in the context of IPA is a topic of growing scientific interest with considerable social and economic implications. Representing the main novelties of the work this study introduces (i) the development of a novel IPA energy and green hydrogen hub located in a tropical region (Singapore); (ii) a multi-objective optimization approach to analyse synthesize and optimize the design and operation of the hydrogen and energy hub with the aim of supporting decision-making for decarbonization investments. A sensitivity analysis identifies key parameters affecting optimization results indicating that for large hydrogen demands imported ammonia economically outperforms other green hydrogen carriers. Conversely local hydrogen production via electrolysis becomes economically viable when the capital cost of alkaline electrolyser drops by at least 30 %. Carbon tax influences the choice of green hydrogen but its price variation mainly impacts system operation rather than design. Fuel cells and batteries are not considered economically feasible solutions in any scenario.

The high potential in renewable energy sources (RES) and the availability of strategic minerals for green hydrogen technologies place Africa in a promising position for the development of a climate-compatible economy leveraging on hydrogen. This study reviews the potential hydrogen value chain in Africa considering production and final uses while addressing perspectives on policies possible infrastructures and facilities for hydrogen logistics. Through scientific studies research and searching in relevant repositories this review features the collection analysis of technical data and georeferenced information about key aspects of the hydrogen value chain. Detailed maps and technical data for gas transport infrastructure and liquefaction terminals in the continent are reported to inform and elaborate findings about readiness for hydrogen trading and domestic use in Africa. Specific maps and technical data have been also collected for the identification of potential hydrogen offtakers focusing on individual industrial installations to produce iron and steel chemicals and oil refineries. Finally georeferenced data are presented for main road and railway corridors as well as for most important African ports as further end-use and logistic platforms. Beyond technical information this study collects and discusses more recent perspectives about policies and implementation initiatives specifically addressing hydrogen production logistics and final use also introducing potential criticalities associated with environmental and social impacts.

The literature lacks a systematic analysis of HRS equipment and operating standards. Researchers policymakers and HRS operators could find this information relevant for planning the network's future expansion. This study is intended to address this information need by providing a comprehensive strategic overview of the regulations currently in place for the construction and maintenance of hydrogen fueling stations. A quick introduction to fundamental hydrogen precautions and hydrogen design is offered. The paper therefore provides a quick overview of hydrogen's safety to emphasize HRS standards rules and regulations. Both gaseous and liquid safety issues are detailed including possible threats and installation and operating expertise. After the safety evaluation layouts equipment and operating strategies for HRSs are presented followed by a review of in-force regulations: internationally by presenting ISO IEC and SAE standards and Europeanly by reviewing the CEN/CENELEC standards. A brief and concise analysis of Italy's HRS regulations is conducted with the goal of identifying potential insights for strategic development and more convenient technology deployment.

Aviation is one of the most important industries in the current global scenario but it has a significant impact on climate change due to the large quantities of carbon dioxide emitted daily from the use of fossil kerosene-based fuels (jet fuels). Although technological advancements in aircraft design have enhanced efficiency and reduced emissions over the years the rapid growth of the aviation industry presents challenges in meeting the environmental targets outlined in the “Flightpath 2050” report. This highlights the urgent need for effective decarbonisation strategies. Hydrogen propulsion via fuel cells or combustion offers a promising solution with the combustion route currently being more practical for a wider range of aircraft due to the limited power density of fuel cells. In this context this paper designs and models a nitrogen–hydrogen heat exchanger architecture for use in an innovative hydrogen-propelled aircraft fuel system where the layout was recently proposed by the same authors to advance sustainable aviation. This system stores hydrogen in liquid form and injects it into the combustion chamber as a gas making the cryogenic heat exchanger essential for its operation. In particular the heat exchanger enables the vaporisation and superheating of liquid hydrogen by recovering heat from turbine exhaust gases and utilising nitrogen as a carrier fluid. A pipe-in-pipe design is employed for this purpose which to the authors’ knowledge is not yet available on the market. Specifically the paper first introduces the proposed heat exchanger architecture then evaluates its feasibility with a detailed thermodynamic model and finally presents the calculation results. By addressing challenges in hydrogen storage and usage this work contributes to advancing sustainable aviation technologies and reducing the environmental footprint of air travel.

Growing energy demands and increasing concerns about climate change have spurred new approaches in both policy and industry with a focus on transforming current energy systems in modern energy hubs. In this context green hydrogen produced through electrolysis process powered by renewable energy sources emerges as a highly versatile and promising solution for decarbonising sectors and provide alternative fuels for process and transportation. This study models and simulates an integrated system comprising desalination brine treatment and electrolysis to generate green hydrogen fuelled entirely by solar energy. The desalination unit produces demineralised water suitable for electrolysis while alternative brine management strategies are explored for scenarios where brine discharge back to the sea is restricted. An economic analysis further evaluates cost-effective system configurations by varying component sizes. To demonstrate the model potential a case study for green hydrogen production based on seawater desalination was conducted for an Italian port city and extended to three other sites with different annual solar radiation. The objective is to determine configurations that minimise hydrogen cost and identify required incentives. The economic performance of the system in terms of the Levelized Cost of Hydrogen ranges from 5 to 8 €/kg while the required incentives to make green hydrogen competitive with blue hydrogen production systems vary between 7 and 12 M€ across the analysed configurations. Furthermore the analysis provides valuable insights into the potential of coastal areas to serve as critical hubs for green hydrogen production given the abundant availability of seawater. Ports with their existing infrastructure and proximity to maritime transport represent ideal locations for integrating renewable energy sources with hydrogen production facilities.

The increase in power generation facilities from nonprogrammable renewable sources is posing several challenges for the management of electrical systems due to phenomena such as congestion and reverse power flows. In mitigating these phenomena Power-to-Gas plants can make an important contribution. In this paper a linear optimisation study is presented for the sizing of a Power-to-Hydrogen plant consisting of a PEM electrolyser a hydrogen storage system composed of multiple compressed hydrogen tanks and a fuel cell for the eventual reconversion of hydrogen to electricity. The plant was sized with the objective of minimising reverse power flows in a medium-voltage distribution network characterised by a high presence of photovoltaic systems considering economic aspects such as investment costs and the revenue obtainable from the sale of hydrogen and excess energy generated by the photovoltaic systems. The study also assessed the impact that the electrolysis plant has on the power grid in terms of power losses. The results obtained showed that by installing a 737 kW electrolyser the annual reverse power flows are reduced by 81.61% while also reducing losses in the transformer and feeders supplying the ring network in question by 17.32% and 29.25% respectively on the day with the highest reverse power flows.

The decarbonization of the maritime sector represents a priority in the energy policy agendas of the majority of Countries worldwide and the International Maritime Organization (IMO) has recently revised its strategy aiming for an ambitious zero-emissions scenario by 2050. In these regards there is a broad consensus on hydrogen as one of the most promising clean energy vectors for maritime transport and a key towards that goal. However to date an international regulatory framework for the use of hydrogen on-board of ships is absent this posing a severe limitation to the adoption of hydrogen technologies in this sector. To cope with this issue this paper presents a preliminary gap assessment analysis for the International Code of Safety for Ship Using Gases or other Low-flashpoint Fuels (IGF Code) with relation to hydrogen as a fuel. The analysis is structured according to the IGF Code chapters and a bottom-up approach is followed to review the code content and assess its relevance to hydrogen. The risks related to hydrogen are accounted for in assessing the gaps and providing a first level set of recommendations for IGF Code updates. By this means this work settles the basis for further research over the identified gaps towards the identification of a final set of recommendations for the IGF Code update.

This study presents preliminary findings from an experimental campaign conducted on a pilot-scale green hydrogen production plant powered by a photovoltaic (PV) system. The integrated setup implemented at the University “Mediterranea” of Reggio Calabria includes renewable energy generation hydrogen production via electrolysis on-site storage and reconversion through fuel cells. The investigation assessed system performance under different configurations (on-grid and selective stand-alone modes) focusing on key operational phases such as inerting purging pressurization hydrogen generation and depressurization. Results indicate a strong linear correlation between the electrolyser’s power setpoint and the pressure rise rate with a maximum gradient of 0.236 bar/min observed at 75% power input. The system demonstrated robust and stable operation efficient control of shutdown sequences and effective integration with PV input. These outcomes support the technical feasibility of small-scale hydrogen systems driven by renewables and offer valuable reference data for calibration models and future optimization strategies.

Ammonia is a particularly promising hydrogen carrier due to its relatively low cost high energy density its liquid storage and to its production from renewable sources. Thus in recent years great attention is devoted to this fuel for realizing next generation refueling stations according to a carbon-free energy economy. In this paper a distributed onsite refueling station (200 kg/day of hydrogen filling 700-bar HFCEVs (Hybrid Fuel Cell Electric Vehicles) with about 5 kg of hydrogen in 5 min) based on ammonia feeding is studied from the energy and economic point of views. The station is designed with a modular configuration consisting of more sections: i) the hydrogen production section ii) the electric energy supplier section iii) the compression and storage section and the refrigeration/dispenser section. The core of the station is the hydrogen production section that is based on an ammonia cracking reactor and its auxiliaries; the electric energy demand necessary for the station operation (i.e. the hydrogen compression and refrigeration) is satisfied by a PEMFC (Proton-Exchange Membrane Fuel Cell) power module. Energy performance according to the hydrogen daily demand has been evaluated and the estimation of the levelized cost of hydrogen (LCOH) has been carried out in order to establish the cost of the hydrogen at the pump that can assure the feasibility of this novel refueling station.

In Southern Italy near the Mediterranean Sea mobility services like cars bicycles scooters and materialhandling forklifts are frequently required in addition to multimodal local transportation services such as trains ferry boats and airplanes. This research proposes an innovative concept of hydrogen valley virtually simulated in Matlab/Simulink environment located in Calabria. As a novelty hydrogen is produced centrally and delivered via fuel cell hybrid trains to seven hydrogen refueling stations serving various mobility hubs. The centralized production facility operates with a nominal capacity of about 4 tons/day producing hydrogen via PEM electrolysis and storing hydrogen at 200 bar with a hydrogen compressor. As the size of vehicle fleets and the cost of acquiring renewable energy through power purchase agreements vary the hydrogen valley is examined from both a technical and an economic perspective analyzing: the values of the levelized cost of hydrogen the energy consumption and the energy efficiency of the energy systems. Specifically the levelized cost of hydrogen reached competitive values close to 5 €/kg of hydrogen under the most optimistic scenarios with fleet conversions of more than 60 % and a power purchase agreement price lower than 150 €/MWh. Then the benefits of hydrogen rail transport in terms of emissions reduction and health from an economic standpoint are compared to conventional diesel trains and fully electric trains saving respectively 3.2 ktons/year and 0.4 ktons/year of carbon dioxide equivalent emissions and corresponding economic benefits of respectively 51 and 0.548 million euros.

The increasing depletion of fossil fuels and their environmental impact have led to the development of fuel cell hybrid electric vehicles. By combining fuel cells with batteries these vehicles offer greater efficiency and zero emissions. However their energy management remains a challenge requiring advanced strategies. This paper presents a comparative study of two developed energy management strategies: a deterministic rule-based approach and a fuzzy logic approach. The proposed system consists of a proton exchange membrane fuel cell (PEMFC) as the primary energy source and a lithium-ion battery as the secondary source. A comprehensive model of the hybrid powertrain is developed to evaluate energy distribution and system behaviour. The control system includes a model predictive control (MPC) method for fuel cell current regulation and a PI controller to maintain DC bus voltage stability. The proposed strategies are evaluated under standard driving cycles (UDDS and NEDC) using a simulation in MATLAB/Simulink. Key performance indicators such as fuel efficiency hydrogen consumption battery state-of-charge and voltage stability are examined to assess the effectiveness of each approach. Simulation results demonstrate that the deterministic strategy offers a structured and computationally efficient solution while the fuzzy logic approach provides greater adaptability to dynamic driving conditions leading to improved overall energy efficiency. These findings highlight the critical role of advanced control strategies in improving FCHEV performance and offer valuable insights for future developments in hybrid-vehicle energy management.