Italy

This study offers a comprehensive analysis of the feasibility of green hydrogen economies in Western and Southern African regions focusing on the ECOWAS and SADC countries. Utilizing a novel approach based on composite indicators the research evaluates the potential readiness and overall feasibility of green hydrogen production and export across these regions. The study incorporates various factors including the technical potential of renewable energy sources water resource availability energy security and existing infrastructure for transport and export. Country-specific analyses reveal unique insights into the diverse potential of nations like South Africa Lesotho Ghana Nigeria Angola and Namibia each with its unique strengths and challenges in the context of green hydrogen. The research findings underscore the complexity of developing green hydrogen economies highlighting the need for nuanced region-specific approaches that consider technical socioeconomic geopolitical and environmental factors. The paper concludes that cooperation and integration between countries in the regions may be crucial for the success of a future green hydrogen economy

Green hydrogen has emerged as a promising energy vector for the decarbonisation of heavy industry. The EU and national governments have recently introduced incentives to address the high costs of green hydrogen production and accelerate the economic development of hydrogen. This study investigates the local production of green hydrogen to decarbonise the high-temperature process heat demand of a heavy industry located in Italy. The hydrogen generation is powered by PV electricity and from the electric grid. We have optimised the sizes of the energy system components including battery storage and hydrogen tanks. The Levelised Cost of Hydrogen (LCOH) was found to be 7.7 EUR/kg in the unincentivised base scenario but this amount significantly reduced to 3.3 EUR/kg when incentives on hydrogen production in abandoned industrial areas were considered. Thanks to such incentives the greenhouse gas emissions decreased by as much as 85 % with respect to the non-incentivised base case. Our results show that the effect of the incentives on the design and economics of the system is comparable with the expected reductions in equipment costs over the next decade. Importantly our findings reveal a linear relationship between Capital Costs and LCOH thereby enabling precise cost estimations to be made for the considered location without any further simulations. A side effect of the size optimisation in the presence of incentives is an increase of the plant footprint. However the limited availability of land could lead to non-optimal configurations with important impacts on emission intensity and LCOH.

This paper provides a comprehensive review and outlook on power converters devised for supplying polymer electrolyte membrane (PEM) electrolyzers from photovoltaic sources. The produced hydrogen known as green hydrogen is a promising solution to mitigate the dependence on fossil fuels. The main topologies of power conversion systems are discussed and classified; a loss analysis emphasizes the issues concerning the electrolyzer supply. The attention is focused on power converters of rated power up to a tenth of a kW since it is a promising field for a short-term solution implementing green hydrogen production as a decentralized. It is also encouraged by the proliferation of relatively cheap photovoltaic low-power plants. The main converters proposed by the literature in the last few years and realized for practical applications are analyzed highlighting their key characteristics and focusing on the parameters useful for designers. Future perspectives are addressed concerning the availability of new wide-bandgap devices and hard-to-abate sectors with reference to the whole conversion chain.

In this study a novel thermo-economic analysis on a membrane reactor adopted to generate hydrogen coupled to a carbon-dioxide capture system is proposed. Exergy destruction fuel and environmental as well as pur chased equipment costs have been accounted to estimate the cost of hydrogen production in the aforementioned integrated plant. It has been found that the integration of the CO2 capture system with the membrane reactor is responsible for the reduction of the hydrogen production cost by 12 % due to the decrease in environmental penalty cost. In addition the effects of operating parameters (steam-to-carbo ratio and biogas temperature) on the hydrogen production cost are investigated. Hence this work demonstrates that the latter can be decreased by approximately 2 $/kgH2 when steam to carbon ratio increases from 1.5 to 4. The analyses reveal that steam-tocarbo ratio increases exergy destruction cost affecting consequently also the hydrogen production cost. How ever from a thermodynamic point of view it enhances the hydrogen production in the membrane reactor mutually lowering the hydrogen production cost. It has been also estimated that a decrease in the biogas inlet temperature from 450 to 400◦C can reduce the hydrogen production cost by 7 %. This study demonstrates that the fuel cost is a major economic parameter affecting commercialization of hydrogen production while exergy destruction and environmental costs are also significant factors in determining the hydrogen production cost.

The Mediterranean basin has been characterized by a net flow of fossil commodities from the North African shore to Southern Europe and the Middle East for decades; however decarbonizing the energy system implies to substantially modify this situation turning the current “black dialogue” into a “green dialogue” (i.e. based on the exchange of renewable electricity and green hydrogen). This paper presents a feasibility study conducted to estimate the potential green hydrogen production by electrolysis in three Tunisian sites. It shows and compares several plant layouts varying the size and typology of renewable electricity generators and electrolyzers. The work adopts local weather data and technical features of the technologies in the computations and accounts for site specific topographical and infrastructural constraints such as land available for construction and local power grid connection capacities. It shows that configurations able to produce large quantities of green hydrogen may not be compliant with such constraints basically nullifying their contribution in any hydrogen strategy. Finally results show that the LCOH lies in the range 1.34 $/kgH2 and 4.06 $/kgH2 depending on both the location and the combination of renewable electricity generators and electrolyzers.

The aviation industry is facing challenges related to its environmental impact and thus the pressing need to develop aircraft technologies aligned with the society climate goals. Hydrogen is emerging as a potential clean fuel for aviation as it offers several advantages in terms of supply potential and weight specific energy. One of the key factors enabling the use of H2 in aviation is the development of reliable and safe storage technologies to be integrated into aircraft design. This work provides an overview of the technologies currently being investigated or developed for the storage of hydrogen within the aircraft which would enable the use of hydrogen as a sustainable fuel for aviation with emphasis on tanks material and structural aspects. The requirements dictated by the need of integrating the fuel system within existing or ex-novo aircraft architectures are discussed. Both the storage of gaseous and liquid hydrogen are considered and the main challenges related to the presence of either high internal pressures or cryogenic conditions are explored in the background of recent literature. The materials employed for the manufacturing of hydrogen tanks are overviewed. The need to improve the storage tanks efficiency is emphasized and issues such as thermal insulation and hydrogen embrittlement are covered as well as the reference to the main structural health monitoring strategies. Recent projects dealing with the development of onboard tanks for aviation are eventually listed and briefly reviewed. Finally considerations on the tank layout deemed more realistic and achievable in the near future are discussed.

The goal of achieving a zero-emission energy system by 2050 requires accurate energy planning to minimise the overall cost of the energy transition. Long-term energy models based on cost-optimal solutions are extremely dependent on the cost forecasts of different technologies. However such forecasts are inherently uncertain. The aim of the present work is to identify a cost-optimal pathway for the Italian energy system decarbonisation and assess how renewable cost scenarios can affect the optimal solution. The analysis has been carried out with the H2RES model a single-objective optimisation algorithm based on Linear Programming. Different cost scenarios for photovoltaics on-shore and off-shore wind power and lithium-ion batteries are simulated. Results indicate that a 100% renewable energy system in Italy is technically feasible. Power-to-X technologies are crucial for balancing purposes enabling a share of non-dispatchable generation higher than 90%. Renewable cost scenarios affect the energy mix however both on-shore and off-shore wind saturate the maximum capacity potential in almost all scenarios. Cost forecasts for lithium-ion batteries have a significant impact on their optimal capacity and the role of hydrogen. Indeed as battery costs rise fuel cells emerge as the main solution for balancing services. This study emphasises the importance of conducting cost sensitivity analyses in long-term energy planning. Such analyses can help to determine how changes in cost forecasts may affect the optimal strategies for decarbonising national energy systems.

Green hydrogen production and storage are vital in mitigating carbon emissions and sustainable transition. However the high investment cost and management requirements are the bottleneck of utilizing hybrid hydrogen-based systems in microgrids. Given the necessity of cost-effective and optimal design of these systems the present study examines techno-economic feasibility of integrating hybrid hydrogen-based systems into an outdoor test facility. With this perspective several solar-driven hybrid scenarios are introduced at two energy storage levels namely the battery and hydrogen energy storage systems including the high-pressure gaseous hydrogen and metal hydride storage tanks. Dynamic simulations are carried out to address subtle interactions in components of the hybrid system by establishing a TRNSYS model coupled to a Fortran code simulating the metal hydride storage system. The OpenStudio-EnergyPlus plugin is used to simulate the building load validate against experimental data according to the measured data and monitored operating conditions. Aimed at enabling efficient integration of energy storage systems a techno-enviro-economic optimization algorithm is developed to simultaneously minimize the levelized cost of the electricity and maximize the CO2 mitigation in each proposed hybrid scenario. The results indicate that integrating the gaseous hydrogen and metal hydride storages into the photovoltaic-alone scenario enhances 22.6% and 14.4% of the annual renewable factor. Accordingly the inclusion of battery system to these hybrid scenarios gives a 30.4% and 20.3 % boost to the renewable factor value respectively. Although the inclusion of battery energy storage into the hybrid systems increases the renewable factor the results imply that it reduces the hydrogen production rate via electrolysis. The optimized values of the levelized cost of electricity and CO2 emission for different scenarios vary in the range of 0.376–0.789 $/kWh and 6.57–9.75 ton respectively. The multi-criteria optimizations improve the levelized cost of electricity and CO2 emission by up to 46.2% and 11.3% with respect to their preliminary design.

Hydrogen refueling stations (HRSs) are key infrastructures rapidly spreading out to support the deployment of fuel cell electric vehicles for several mobility purposes. The research interest in these energy systems is increasing focusing on different research branches: research on innovation on equipment and technology proposal and development of station layout and research aiming to provide experimental data sets for perfor mance investigation. The present manuscript aims to present an overview of the most recent literature on hydrogen stations by presenting the technological status of the system at the global level and their research enhancement on the involved components and processes. After the review of the mentioned aspects this paper will present the already existing layouts and the potential configurations of such infrastructures considering several options of the delivery routes the end-user destination and hydrogen storage thermodynamic status whether liquid or gaseous.

The European Commission through the REPowerEU plan and the “Fit for 55” package aims to reduce fossil fuel dependence and greenhouse gas emissions by promoting electric and fuel cell hybrid electric vehicles (EV-FCHEVs). The transition to this mobility model requires energy systems that are able to provide both electricity and hydrogen while reducing the reliance of residential buildings on the national grid. This study analyses a poly-generative (PG) system composed of a Solid Oxide Fuel Cell (SOFC) fed by biomethane a Photovoltaic (PV) system and a Proton Exchange Membrane Electrolyser (PEME) with electric vehicles used as dynamic storage units. The assessment is based on simulation tools developed for the main components and applied to four representative seasonal days in Rende (Italy) considering different daily travel ranges of a 30-vehicle fleet. Results show that the PG system provides about 27 kW of electricity 14.6 kW of heat and 3.11 kg of hydrogen in winter spring and autumn and about 26 kW 14 kW and 3.11 kg in summer; it fully covers the building’s electrical demand in summer and hot water demand in all seasons. The integration of EV batteries reduces grid dependence improves renewable self-consumption and allows for the continuous and efficient operation of both the SOFC and PEME demonstrating the potential of the proposed system to support the green transition.