Italy

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.