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The Contribution of Biogas to the Electricity Supply Chain: An Italian Life Cycle Assessment Database
Get PDFThe transition towards energy efficiency measures and green energy sources is strongly fostered by the European Union. Italy is among the EU countries that have heavily invested in renewable energy sources, more than doubling their share in gross final energy consumption. In particular, biogas has a pivotal role in the generation of electricity and can also be upgraded into biomethane, with a higher and more stable energy content. In this study, the sustainability of the supply chain of electricity from biogas in Italy has been thoroughly analyzed in the broader framework of the ARCADIA (Life Cycle Approach in Public Procurement and Italian LCA Database for Resource Efficiency) project. The environmental assessment, carried out by means of Life Cycle Assessment (LCA), provides a two-fold perspective. Firstly, it allows us to identify the main hotspots of the investigated system, such as the cultivation of dedicated crops, and to provide useful insights for improving environmental performance. Furthermore, a focus on the modeling of the dataset related to the production of electricity from biogas within the Italian electricity mix represents a step ahead in the LCA research, filling the lack of site-specific databases for reliable LCA results
Characterization of the FOOT neutron detectors for nuclear fragmentation measurements at the n_TOF facility
No full textFOOT (FragmentatiOn Of Target) is an applied nuclear physics experiment with the aim of performing high precision cross section measurements for fragmentation reactions of interest in hadrontherapy and radiation protection in space. The physics program of the experiment foresees a set of measurements with light ion beams, such as C and O, in the energy range of 100-800 MeV/u interacting with tissue-like and shielding material targets. The setup was initially conceived for the detection of charged fragments and, in 2021, the Collaboration started the study of possible solutions for neutron detection. Two detection systems have been proposed: one based on BC-501A liquid scintillators with neutron/γ discrimination capabilities and a system based on BGO crystals operated in phoswich mode. In 2022, a dedicated data acquisition campaign was carried out at the n_TOF facility at CERN to evaluate the capabilities of the two systems. First, the neutron/γ discrimination efficiency of the BC-501A system was studied using radioactive sources. Then, the two systems were placed in the n_TOF experimental area to study their neutron detection efficiency under a well characterized neutron beam. In this work, the first preliminary results concerning the characterization of the two possible neutron detectors of FOOT are presented
Co-designed agro-climate indicators identify different future climate effects for grape and olive across Europe
Get PDFCo-design processes involving the scientific community, practitioners, end users and stakeholders can efficiently characterize harmful weather events during the growing season that potentially result in losses of crop yield and quality. This study builds on the experience of the EU Horizon 2020 project MED-GOLD for grape and olive. The identified agro-climate indicators are extended from the MED-GOLD regions to the entire ones where grape and olive are currently grown in Europe and Turkey, and used to assess climate change impacts with intrinsic adaptation relevance stemming from the co-design process. Before 2000, only a low fraction of the European grape and olive growing areas was exposed to extreme weather events as revealed by the agro-climate indicators, but this has changed rapidly afterward. Projections show increasingly widespread extreme high temperature events from 2020 to 2080. Approximately one-third of grapevine regions and over half of olive cultivation areas are expected to experience extreme drought conditions. Additionally, the frequency of compound extreme events will increase in the future, especially in the Mediterranean region and under the high-end emission scenario RCP8.5. This outcome calls for a new decision-making mindset that embeds expected levels of climate variability and extremes as the “new normal” for grape and olive in Europe. This will facilitate deployment of the required biophysical, economic and policy adaptation tools
Environmental and economic performance of chemical and biological processes for treating petroleum hydrocarbon-contaminated soil: An experimental study
Get PDFOver the past ten years, researchers have applied various approaches to treat petroleum hydrocarbon-contaminated soil and assess its performance based on removal efficiencies and not on its environmental and economic impacts. In this study, the environmental and economic performances of the operational stages of electro-Fenton and bio-slurry technologies are investigated and compared using a life cycle assessment to assess the environmental and economic performances in treating petroleum hydrocarbon-polluted soil. The data used in this study were collected from primary and secondary sources, and the potential 18 environmental impacts were calculated using the ReCiPe 2016 characterization approach in SimaPro 9.5 software. The electro-Fenton process is the most environmentally friendly method, identifying chemicals and energy as major contributors to the environmental impact. Energy is the main hotspot, accounting for 90 % of the total environmental impact. Energy and biosurfactants are the main environmental hotspots in bioslurry processes, accounting for 60 % of the total. The bioslurry process has the highest environmental impact owing to the use of biosurfactants and electricity consumption. The bioslurry process is the most cost-effective, with a life-cycle cost of 7.13/kg) owing to the use of BDD as the electrode, costing 323$/kg
Development of predictive indices for evaluating the UHI adaptation potential of green roof- and wall-based scenarios in the Mediterranean climate
Get PDFUrban heat islands can jeopardize urban inhabitants, but the installation of green roofs (GRs) and walls (GWs) can contribute to mitigating urban overheating. The present study provides novel indices to easily predict the spatial median variation in air temperature at pedestrian heights related to the application of GR- and GW-based scenarios during the hottest hours of a typical summer day by varying the building height (BH), coverage percentage, and leaf area index. The indices are meant to be applied to built areas with 0.3–0.4 urban density in the Mediterranean climate and are derived from regression models fed with the outputs of 281 simulations of three urban areas developed and run in ENVI-met software. The developed models are all highly significant. The GR model shows that mitigation is influenced by all three parameters, and it can estimate mitigation with a root mean square error of 0.05 °C. Compared with the other parameters, the GW models revealed that the BH did not influence the decrease in air temperature. The green façade and living wall (LW) indices predict mitigation with errors of 0.04 °C and 0.05 °C, respectively. However, for the LW model, further parameters should be considered to improve its reliability
Floating Photovoltaic Plant Monitoring: A Review of Requirements and Feasible Technologies
Get PDFPhotovoltaic energy (PV) is considered one of the pillars of the energy transition. However, this energy source is limited by a power density per unit surface lower than 200 W/m2, depending on the latitude of the installation site. Compared to fossil fuels, such low power density opens a sustainability issue for this type of renewable energy in terms of its competition with other land uses, and forces us to consider areas suitable for the installation of photovoltaic arrays other than farmlands. In this frame, floating PV plants, installed in internal water basins or even offshore, are receiving increasing interest. On the other hand, this kind of installation might significantly affect the water ecosystem environment in various ways, such as by the effects of solar shading or of anchorage installation. As a result, monitoring of floating PV (FPV) plants, both during the ex ante site evaluation phase and during the operation of the PV plant itself, is therefore necessary to keep such effects under control. This review aims to examine the technical and academic literature on FPV plant monitoring, focusing on the measurement and discussion of key physico-chemical parameters. This paper also aims to identify the additional monitoring features required for energy assessment of a floating PV system compared to a ground-based PV system. Moreover, due to the intrinsic difficulty in the maintenance operations of PV structures not installed on land, novel approaches have introduced autonomous solutions for monitoring the environmental impacts of FPV systems. Technologies for autonomous mapping and monitoring of water bodies are reviewed and discussed. The extensive technical literature analyzed in this review highlights the current lack of a cohesive framework for monitoring these impacts. This paper concludes that there is a need to establish general guidelines and criteria for standardized water quality monitoring (WQM) and management in relation to FPV systems
Concentrated solar heat for the decarbonization of industrial chemical processes: a case study on crude oil distillation
Get PDFA novel strategy for the decarbonization of crude oil distillation was proposed considering two distillation columns located in Sicily that were simulated by adapting the equipment datasheet of the refinery Raffineria di Milazzo (RAM). The proposed approach consists of the integration of the topping section with a concentrating solar power (CSP) plant to decrease the carbon dioxide emissions and the consumed fossil fuels in the furnaces of the distillation columns. Three hypothetical scenarios of applicative interest were considered. In that most economically sustainable, the use of solar heat allowed a decrease of CO2 emissions of 54.2 kt/year corresponding to a reduction of about 11% of the greenhouse gas emissions joined with the saving of 19.9 kt/year of methane with a rate of return of investment (ROROI) of 16.2%. As a comparison, if the land surface occupied by the CSP plant is used for photovoltaic production of green hydrogen considering an energy consumption of the electrolyzer of 4.70 kWh/Nm3, just 24.6 and 9.0 kt/year of CO2 and methane respectively can be saved and the ROROI decreases to 8.5%. This study indicates that solar heat can be effectively and economically integrated in crude oil distillation to achieve a significant decarbonization of refineries
Performance Evaluation of an Anode-Supported SOFC Short-Stack Operating with Different Fuel Blends as Stationary-CHP System
Get PDFIn the perspective of the transition of gas grids towards hydrogen/natural gas blends or even pure hydrogen, Solid Oxide Fuel Cells “SOFC” could play a crucial role as efficient and clean stationary Combined Heat and Power systems, flexibly operating on different feedstocks. A solid oxide fuel cell short stack is analyzed experimentally under different fuel gas compositions which emulate different gas grid transition scenarios. The testing campaign is defined with the aid of a preliminary system-level simulation which assesses system architecture and operating strategy (off-gas recirculation, external reforming, etc). Experimental tests (polarization curves and performance/efficiency maps) are run in different operating conditions in terms of fuel utilization and temperature in three gas composition scenarios. To assess the efficiency of the SOFC unit under the different feedstock operation, different formulations of stack and system efficiencies are proposed and analyzed, based on the boundary conditions considered for the input/output energy streams. Experimental results were key to evaluate the different efficiency definitions proposed; albeit the highest voltage/power is obtained with the 100% H2 scenario, the efficiency may be higher with 100% NG and blend scenarios, due to the lower energy content of the input fuel
Design and Performance of a Linear Flux Pump for the Frascati Coil Cold Test Facility
No full textThe state-of-the-art power supplies for superconducting magnets are bulky, expensive, and subjected to hundreds of kilowatts of power losses during operation producing significant reactive power absorption and harmonic distortion on the power grid. Moreover, current is injected from room temperature to 4 K coils through current leads, which represent a major source of heat load for the cooling system. Flux pumps are contactless, compact power supply systems able to operate superconducting magnets in a nearly persistent current mode with practically negligible operation losses. Although several small-scale experimental tests already proved the concept of flux pumps, no demonstrators suiting the current and voltage rating of fusion magnets have been built, nor a proper design has been developed. In this study, we developed an application-oriented modelling framework for optimized design of linear flux pumps. This paper presents the framework and a design of a linear flux pump demonstrator with a current capability of 2000 A to be integrated into the Frascati Coil Cold Test Facility. Simulations reporting its performance when employed for the energization of a toroidal field coil of the Divertor Tokamak Test (DTT) are described, both for the ramp up and current maintenance regimes, and its efficient modularity exploitation is analyzed
Bending Tolerance of React&Wind Nb3Sn Conductors for Fusion Magnets
Get PDFThe react-and-wind technique for manufacturing of large Nb3Sn fusion magnets (RW) is very attractive because of the superior performance of the Nb3Sn with lower thermal strain compared to the wind-and-react technique. The procedure for magnet winding is also drastically simplified for the RW approach. The flat cable, made of a large number of Nb3Sn strands, is heat treated on a spool with constant radius. Then the cable is unspooled to assemble the conductor with stabilizer/steel jacket and wound on a spool to be shipped to the winding factory, where the conductor is unspooled and wound in the final geometry - either round shape for Central Solenoid or D-shape for Toroidal Field Coils. The bending strain must be controlled during the handling from heat treatment to the final magnet in order not to exceed the irreversible strain limit. For design purposes, it is assumed so far that a bending strain ±0.3% during handling is acceptable. In this work, the bending tolerance of a 63 kA RW fusion conductor is investigated by monitoring the performance in the SULTAN test facility after bending/straightening at decreasing radii till a degradation of the current sharing temperature performance, Tcs, is observed. The experimental assessment of the bending tolerance during handling is a major instrument for dimensioning of the cable thickness and heat treatment radius of the RW conductors for fusion