bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy Efficiency of the Office Buildings in Italy: Insights for the European Taxonomy.
Authors: Aquino Andrea , Bassetti Marco , Grasso Edoardo , Martini Fabrizio , Salvio e Marcello 
Published: December 2024

Abstract
Sustainable investments have led the Italian real estate market over recent years. Large enterprises invest in renovating their building stocks to optimize costs, respond to institutional pressures, and enhance their Environmental, Social, and Governance (ESG) scores. The ESG criteria orient the preferences of today’s investors by measuring a company’s sustainability and profitability; however, the ESG rating systems lack transparency, exposing investors to misleading sustainable initiatives (greenwashing) and risks of financial losses. The EU Taxonomy for Sustainable Activities (EU Regulation 2020/852) defines technical thresholds for sustainability that support investors in making informed decisions. In the building sector, the Taxonomy distinguishes (i) new building construction and (ii) retrofitting existing buildings; the latter is sustainable if it reduces the existing building’s primary energy use by 30% compared to ante-opera or follows the retrofitting guidelines established by the EU directive 2010/31. This work aims to estimate the potential for energy savings and CO2 reduction of the Italian office building stock according to the Taxonomy guidelines. The Energy Efficiency Directive 2012/27/EU (EED) establishes a legislative framework for achieving the European energy efficiency targets. Article 8 of the EED introduced the obligation for large enterprises to submit an energy audit of their production sites every four years, starting from December 2015, and the Italian National Agency for New Technologies, Energy, and the Sustainable Economic Development (ENEA) collects and reviews such energy audits. This study analyzes the energy audits of office buildings submitted by large enterprises in the insurance and banking sectors last year. The database associates the technical features of each building with the main characteristics of its location (e.g., the climate and urban landscape) and energy use. Data show the benefits of retrofitting office building portfolios following the Taxonomy, showing a reduction of energy use and CO2 emissions up to 20% from the current state. Electrification of heating loads is particularly effective in cold climates. At the same time, intense reconstruction produces the highest benefits, but it needs careful resource allocation, driven by cost-benefit analysis.
Thermally-integrated CO2 cycles for MW-scale power generation and storage
Authors: Traverso A. , Maccarini S. , Shamsi S. S. M. , Barberis S. , Persico G. , Romei A. , Kamali K. , Fiaschi D. , Gigliotti F. 
Published: December 2024

Abstract
In an energy scenario driven by Renewable Energy Sources (RES), where more and more bulky quantities of RES should be introduced on the grid, the role of energy storage systems is crucial. Further to already available electric storage technologies (mostly based on batteries), it will be mandatory to have grid flexible large scale energy storages able to operate ramp-up/down with large capacity, whose behaviour/management should be as much similar as possible to traditional power plants (also to guarantee specific grid services like grid frequency regulation via rotating inertia etc.) which are currently used to instantaneously regulate the grid. At this purpose, Pumped Thermal Energy Storage (PTES) offers GWh scale storage without geographical constraints, at reasonable costs, and implementing power and heat pump cycles integrated with thermal energy storage (TES) solutions. The peculiar features of supercritical CO2 (sCO2) make it the ideal candidate to act as working fluid for large scale PTES applications. sCO2 cycles are indeed fully compatible with the temperature range of TES hot storage sources and sCO2 has already been used in commercial HP solutions (even targeting high temperature HPs). In addition, sCO2 allows energy storage to embody a compact design as well, making the whole PTES footprint smaller compared to technologies based on other working fluids. Nevertheless, sCO2 based PTES solutions cannot achieve significant Round Trip Efficiency (RTE): a possible solution to such a limitation is represented by the exploitation of freely available heat sources (like thermal RES or waste heat), which could increase the COP of the charging cycle and, at the end, the electrical-based RTE, therefore in the so-called Thermally Integrated Pumped Thermal Energy Storage (TI-PTES). In the framework of the PRIN 2022 project ECO-SEARCHERS, specific cycle layouts of interest are studied and compared on a thermodynamic basis: the most promising solution is presented in this paper. Finally, the test rig that will be used for laboratory-scale validation of a small size radial bladeless turbine is described, providing a first glance to the technical challenges in realizing and managing sCO2 cycles in practice.
Comparative analysis of a Packed-Bed Thermal Energy Storage operating with pure gases and nanoaerosol.
Authors: Cascetta Mario , Casti Efisio , Cau Giorgio , Petrollese Mario 
Published: December 2024

Abstract
This paper investigates the thermal performance of a packed-bed thermal energy storage (TES) system and the impact of introducing nanoparticles into the working fluid. A one-dimensional transient numerical model based on Local Thermal Non-Equilibrium (LTNE) principle is validated against experimental data. Key parameters, such as temperature distribution and thermocline formation, show good agreement between numerical and experimental results with an average RMSE on the thermocline profile equal to 0.96 K during the charging phase, and 2.74 K during the discharging phase. The effect of adding nanoparticles to the working fluid are then examined. Nanoparticles enhance the fluid’s effective thermal conductivity, improving heat transfer. Numerical simulations indicate that nanoparticle concentration increases the mass flow rate but decreases the volumetric flow rate, resulting in reduced pressure losses within the bed. Higher nanoparticle concentrations significantly enhance the convective heat transfer coefficient. Overall, introducing nanoparticles improves the TES system’s thermal performance without significantly altering its energy storage capacity. The validated model helps optimize TES system design, balancing enhanced thermal properties and increased fluid density.
0D physical model for the charging phase of shell-and-tube Latent Heat Thermal Storage
Authors: Ceglie Vito , Anaclerio Fabio , Camporeale Sergio Mario , Milozzi Adio , Nicolini Daniele , Fornarelli Francesco 
Published: December 2024

Abstract
The transition to sustainable energy raises many issues that need to be addressed in order to develop reliable energy production infrastructures. Among these challenges, the mismatch between primary energy sources and energy loads stands out as a significant barrier to the widespread adoption of renewable technologies. Efficient energy storage solutions are crucial to mitigate this mismatch and facilitate the integration of renewable energy sources into existing grids. In this study, to evaluate the performance of this component within any plant, we focus on developing a simple yet effective model for predicting the behavior of shell-and-tube latent heat thermal energy storage (LHTES) systems limiting the analysis to the melting phase. LHTES systems offer promising potential due to their high energy density and ability to store thermal energy at a slightly constant temperature. However, their performance depends on various factors such as material properties, geometry and operating conditions, which require accurate predictive models for optimization and design purposes. Our proposed model uses fundamental principles of heat transfer and phase change phenomena to simulate the behavior of LHTES systems during the melting phase. By considering factors such as heat transfer coefficients, phase change kinetics and thermal properties of the storage medium, our model aims to provide insight into the thermal performance and efficiency of shell-and-tube LHTES configurations. Through validation against experimental data and numerical simulations, we demonstrate the effectiveness of our model in accurately predicting key performance metrics such as charge rates, temperature distribution within the storage medium, and overall energy storage efficiency. Its simplicity and computational efficiency make it suitable for practical applications, enabling engineers and designers to optimize LHTES systems for specific operating conditions and integration scenarios.
Enhancing tribological performance of External Gear Pumps through CFD Analysis of Textured Surfaces and gear Edge Chamfering
Authors: Casoli Paolo , Masoud Hatami Garousi , Vescovini Carlo Maria 
Published: December 2024

Abstract
External gear pumps (EGP) have become more and more common in a variety of industrial fields because of their advantageous cost-performance ratio, high efficiency, small design, and reliability. EGP are conceptually simple machines, but the design is often difficult, especially to ensure good performance at high working pressures. Among the internal components of EGP, the lateral plates are two important elements that strongly affect the performance of the machine. In this work, computational fluid dynamics (CFD) simulations are performed to investigate the effects of plate with textured surfaces and gear with chamfered edges on the bearing capacity. The simulations of the fluid flow in the oil gap between the gear tooth and the side bushing consider the correct pressure distribution at the inlet and outlet of the meatus, involving in the simulation also the portion of oil in the tooth space volumes surrounding the tooth.
Innovative and self-adaptive energy recovery system in hydraulic cylinders for cyclic operations
Authors: Romagnuolo Luca , Frosina Emma , Hieronymis Carlo Rozzi de , Bordini Giorgio , Senatore Adolfo 
Published: December 2024

Abstract
Conventional hydraulic actuation supply and control systems usually work with a very high energy loss, especially in the field of off-road machinery. In particular, during the lowering phase of a boom of a hydraulic excavator, energy dissipated through lamination in thermal heat is a consistent fraction of the energy required for operating the working cycle. In this paper, an innovative system is presented that can recover a significant fraction of this energy, to make it available for the next working cycle, which adapts the level of energy recovery in order to maximise the overall efficiency.
In the presented system, the conventional hydraulic actuators that operate the boom of a large size hydraulic excavator are replaced with three-chamber actuators, in which the third chamber, obtained inside the cylinder rod, is connected to a secondary hydraulic circuit that involves a series of accumulators: the compression and the subsequent expansion of the amount of gas inside the accumulator allows to, respectively, store the maximum possible recoverable energy, during load lowering phase in the first cycle and deploy it in the next cycle. The initial gas pressure inside the accumulator is set accordingly to the maximum amount of recoverable energy during the cyclic operation, and can be easily changed via a low-displacement auxiliary pump and a feedback control mechanism, without the need of stopping the machine to vary the amount of inert gas inside the accumulators.
A hydraulic manifold has been designed to manage and regulate the flow rates of both the main and the secondary circuits. Pressure losses inside the manifold have been evaluated through CFD analysis, performed in SimericsMP+ environment. The whole system has then been simulated as a lumped parameter model developed in Simcenter Amesim ©. Results from the simulation of the proposed system show that, on a working cycle of 20 s, only 25% of the hydraulic energy required for the conventional system is needed to operate the boom in the proposed configuration.
This method can be easily extended to several hydraulic actuators that realise frequent height changes of the load.
An Electrochemical Impedance Spectroscopy (EIS) analysis of a reversible Solid Oxide Cell (rSOC) for its electrochemical characterisation
Authors: Mennilli Francesca , Giannetti Lorenzo , Ferrario Andrea Monforti , Rossi Mosè , Comodi Gabriele , Pietra Massimiliano Della 
Published: December 2024

Abstract
The Electrochemical Impedance Spectroscopy (EIS) technique is widely used to characterise electrochemical reaction mechanisms. This technique identifies the main phenomena occurring in an electrochemical device. When dealing with Solid Oxide Electrolysers (SOECs) and Fuel Cells (SOFCs), button cells are generally used for improving their structure, choosing the right electrode materials, and testing manufacturing processes. EIS techniques are then employed to evaluate their performance under different operating conditions. However, larger industrial-sized cells are used for being operated in real test environments, meaning that a larger number of experimental tests on ever-increasing cell area are required to evaluate and assess their performance properly. In such a context, this work aims to cover this research gap by providing EIS spectra as preliminary results of an experimental campaign carried out on a 5x5 cm
2 rSOC operating at different conditions in terms of temperature and gas composition. In SOEC mode, an increase in the water content at the fuel electrode leads to unstable conditions and an increase in the polarisation and ohmic resistances. In SOFC mode, a decrease in the hydrogen content at the fuel electrode leads to a maximum increase of the polarisation resistance of 34.17%, while a decrease in the oxygen content at the air electrode leads the system to highly unstable conditions. In both cases, the cell temperature variation leads to a maximum reduction in the ohmic resistance of 12 and 3.8% in SOEC and SOFC modes, respectively.
A MATLAB/Simulink model of a parallel hybrid PEMFC/battery powertrain for passenger cars
Authors: Parmiggiani D. , Antetomaso C. , Martoccia L. , Merola S. , d’Adamo A. 
Published: December 2024

Abstract
The transition towards sustainable transportation solutions needs the development of efficient and environmentally friendly propulsion systems. Among these, Proton Exchange Membrane Fuel Cells (PEMFCs) seem to be a promising solution for sustainable powertrain design. This study presents the development of a MATLAB/Simulink model for a parallel hybrid FC/battery system representative of a passenger car, including all the auxiliary components and sub-systems. The model incorporates electrochemical, heat transfer, and fluid dynamic processes to accurately simulate the dynamic PEMFC stack and system behaviour. By implementing user-defined initial and boundary conditions, the model offers flexibility in simulating real-world scenarios, allowing the investigation of system performance under different environmental and dynamic driving conditions, as prescribed by the latest homologation protocols. Additionally, it accounts for the membrane degradation, which is a critical aspect affecting long-term durability, performance, and efficiency. Furthermore, a Graphic User Interface (GUI) has been developed to simplify the input of the main parameters, embedding the model in a user-friendly yet comprehensive tool designed for students, researchers, and engineers to evaluate the realizability of these efficient technologies. The intrinsic adaptability to model any FC/battery power system under a generic time-varying load constitutes an additional valuable point of the presented study to enable engineering progress, advancing the energy transition via sustainable powertrain solutions.
Retrofitting of a hybrid propulsion shunting locomotive equipped with Fuel Cell and Metal Hydrides storage
Authors: Barberis Stefano , Rivarolo Massimo , Magistri Loredana 
Published: December 2024

Abstract
The use of hydrogen as an energy carrier is more and more interesting in the current energy scenario due to the possibility of utilizing electrolysis as a large-scale energy storage solution for renewable energy plants and its versatility as a fuel in various applications, both stationary (hard-to-abate industries) and in transports. However, the use of hydrogen still presents technological challenges, particularly concerning its storage and transportation. The use of metal hydrides (MH) intermetallic compounds to store the gas helps to reduce the hazards and technological complexities that other storage systems (such as high-pressure compressed hydrogen or liquid hydrogen) may entail, allowing low pressure storage.
These compounds are capable of absorbing hydrogen atoms into their interstitial lattice, releasing them once heated with a sufficient amount of heat.
This study assesses the possibility of using (instead of a compressed hydrogen storage system) a metal hydride system onboard of a shunting locomotive (to be used in ports and interports) as part of a retrofitting process aimed at converting the locomotive itself to hydrogen, equipping it with a PEMFC driven power-train whose waste heat could be valorised to drive the management of MH discharge. Based on the locomotive’s characteristics and constraints (weights and size, amount of fuel to be stored onboard according to its mission profile), the amount of hydrogen that could be installed on the vehicle was assessed, looking at the feasibility of storing H2 on board via MH due to space and weight constraints.
In this analysis, three different metallic compounds (LaNi5, TiFe, TiMn1.5) widely used in the field of metal hydrides, and various tank designs (which allow different heat exchange between the MH and the heat transfer fluid coming from the PEMFC) have been considered in order. The different tank layouts were compared to analyse the thermal management of the metal hydride discharge process through the recovery of waste heat from the locomotive’s power-train fuel cell, thus targeting solutions for the final MH tank sizing and design.
Evaluation of water/energy intensity of green hydrogen production plants in Africa scenario
Authors: Rivarolo Massimo , Barberis Stefano , Portesine Aurora , Massardo Aristide F. 
Published: December 2024

Abstract
The recent environmental concerns due to CO2 emissions continuous growth and the contemporary increase in fossil fuel prices on international markets are two important factors that are moving the interest towards green and carbon free fuels. In this sense, green hydrogen production from electrolysis is a very promising option as a way to store electrical energy from renewable energy sources (RES) as fuel. However, two inputs are necessary: electrical energy and water. Whereas in EU scenario, electrical energy costs are the ones which affect more the feasibility, in Africa scenario, the availability of RES, in particular solar, is higher in many Countries, allowing for lower energy costs. Green hydrogen production can represent an important resource for microgrids and remote local communities, where the electrical and gas grids are not well developed. However, in this scenario, the large amount of high purity demineralized water required for the process may represent a critical aspect that must be considered. In this study, three different microgrids located in Africa (Kenya, Mali and South Africa) are analysed, considering solar PV installation, three different water intake options (ground water, surface water and seawater), and the impact of the water purification process on the whole plant from both the energy and the economic standpoints. The analysis is performed for the three scenarios, assuming the same electrolyser size (1 MW), considering PEM commercial systems and evaluating the feasibility in the three scenarios, optimizing the PV plant size (range 1-10 MW) to minimize H2 production cost. For the chosen configurations, the water-energy-food nexus is investigated, as both the water intensity and the required area (not available for agriculture purpose) are evaluated.
Feasibility study and optimal sizing of H2 storage and PEM fuel cells onboard ships
Authors: Rivarolo M. , Raggio M. , Montagna G.N. , Barberis S. 
Published: December 2024

Abstract
The International Maritime Organization (IMO) established a challenging global strategy in 2023 to reduce greenhouse gas (GHG) emissions from international shipping by 70% by 2040. Achieving these targets necessitates radical actions, including the use of carbon free fuels and hybrid-alternative propulsion systems. The NEREHYDES (Novel hEat REcovery solutions on board of fuel cell equipped vessels for metal HYDridES storage optimal management) national research project aims to optimize the design and management of a hybrid system with hydrogen fuelled Proton Exchange Membrane Fuel Cells (PEMFC) and diesel Internal Combustion Engines (ICE) on board short-travel ferries for zero-emission operation in coastal and harbour areas. The new PEMFC - MH system is designed to operate mostly in harbour, while the traditional ICE operates during navigation in open sea. The study consists of a pre-feasibility analysis for retrofitting an existing ferry by including a PEMFC system. For the hydrogen storage required for the considered travel distances, metal hydrides (MH) storage is employed, allowing for the H2 storage at low pressure and close to room temperature.
The study is carried out considering the requirements of two real vessels operating in Sicily (Italy) and their daily travelling routes, aiming to find the optimal sizes for both PEMFC and MH systems, minimizing the overall costs and volumes to properly fit this additional system into the existing ferries. Finally, a preliminary techno-economic and environmental assessment is performed to compare the different solutions.
Feasibility Analysis of Green Hydrogen Production Systems for Decarbonized Heating Applications: A Dynamic Modelling Approach on Simulink
Authors: Caravelli Alessandro , Pozzessere Adriano , Veroli Mario Di , Cedola Luca , Verones Sara , Borello Domenico 
Published: December 2024

Abstract
This paper presents a dynamic model of a hydrogen production system aimed at residential heating applications, utilizing MATLAB® and Simulink® softwares. The global model is divided into different macro-sections, each covering a specific role in the hydrogen production and distribution process. These include the photovoltaic field, the electrolyzer, the short-term and long-term storage sections and the end-users. The graphical interface of Simulink is employed, with particular reliance placed on the Simscape library for the modelling and simulation of physical lines. The control logic that governs the operation of the system is implemented using the Simulink tool Stateflow, thereby ensuring efficient management of hydrogen production, storage, and distribution phases. Two distinct scenarios are analysed, each considering different weather data, thermal demand distribution and infrastructure configuration. For each Scenario, simulation results provided a detailed trend of PV power production and electrolyser power consumption, hydrogen production, variations in storage tank pressures, as well as power consumption by auxiliary systems. A comparative analysis with fossil fuel sources is then assessed by calculating the overall reduction of CO2 emissions due to green hydrogen production. In conclusion, this paper provides a comprehensive framework for modelling, simulating, and evaluating green hydrogen production systems, offering insights into their potential as sustainable energy solutions for residential heating decarbonization.