1,721,006 research outputs found
Analysis of the existing barriers for the market development of power to hydrogen (P2H) in Italy
Full text linkNew technological solutions are required to control the impact of the increasing presence of renewable energy sources connected to the electric grid that are characterized by unpredictable production (i.e., wind and solar energy). Energy storage is becoming essential to stabilize the grid when a mismatch between production and demand occurs. Among the available solutions, Power to Hydrogen (P2H) is one of the most attractive options. However, despite the potential, many barriers currently hinder P2H market development. The literature reports general barriers and strategies to overcome them, but a specific analysis is fundamental to identifying how these barriers concretely arise in national and regional frameworks, since tailored solutions are needed to foster the development of P2H local market. The paper aims to identify and to analyze the existing barriers for P2H market uptake in Italy. The paper shows how several technical, regulatory and economic issues are still unsolved, resulting in a source of uncertainty for P2H investment. The paper also suggests possible approaches and solutions to address the Italian barriers and to support politics and decision-makers in the definition and implementation of the national hydrogen strategy
Environmental life cycle assessment of the innovative ejectors plant technology for sediment management in harbours
No full textMisure per contrastare l’emergenza durante l’epidemia da SARS-CoV-2: perché il controllo efficace della diffusione del contagio non può prescindere dal controllo dell’umidità dell’aria ambiente
No full textÈ ormai noto dalla letteratura scientifica che la trasmissione diretta del virus SARS-CoV-2 da un soggetto infetto ad un soggetto suscettibile avvenga attraverso le goccioline che sono emesse, per esempio, con il respiro, durante la conversazione, con un colpo di tosse o con uno starnuto. Per questo motivo, il primo punto da cui partire per studiare una strategia efficace di controllo della diffusione del contagio è lo studio del percorso che le goccioline contaminate fanno una volta emesse. Nota la traiettoria può essere definita la distanza interpersonale oltre alla quale due o più individui possono permanere con probabilità di contaminazione molto piccola. Sebbene possa apparire banale, studiare la traiettoria di una gocciolina in aria è un problema complesso che richiede strumenti propri della Fisica Tecnica e dell’Ingegneria Impiantistica, in particolare quella dedicata allo studio dell’Ingegneria dei Flussi Multifase, in termini anglosassoni Multiphase Flow Engineering
Environmental Life Cycle Assessment of Innovative Ejectors Plant Technology for Sediment By-Pass in Harbours and Ports
Full text linkSedimentation is the natural process of sediment transportation and deposition in quiescent water conditions. Sedimentation can affect the functionality of ports, harbours and navigation channels by reducing water depth, making navigation difficult, if not impossible. Different solutions are available to guarantee infrastructure functionality against sedimentation, with maintenance dredging being the most widely adopted. Alternative technologies for dredging have been developed and tested to reduce the environmental concerns related to dredging operations. Among other solutions, applying a sediment by-pass system based on a jet pump emerged as one of the most promising. While the existing literature covers the techno-economic aspects of sediment by-pass systems, the environmental impacts must be better evaluated and assessed. This paper aims to resolve this gap by evaluating, through the ReCiPe2016 life cycle assessment (LCA) methodology, the environmental impact of an innovative sediment by-pass system called an "ejectors plant". The LCA results are based on the demonstrator established in Cervia Harbour in Italy, which was extensively monitored for 15 months during its operation. This paper shows how energy consumption during the operation phase highly affects the considered midpoint and endpoint categories. For example, the GWP100 of the ejectors plant, considering the Italian electricity mix, equals 1.75 million tons of equivalent CO2 over 20 years, while under a low-carbon scenario, it is reduced to 0.17. In that case, material consumption in the construction phase becomes dominant, thus highlighting the importance of eco-innovation of ejectors plants to minimise oxidant formation. Finally, this paper compares the ejectors plant and traditional dredging through environmental LCA. The ejectors plant had a lower impact in all categories except for GWP-related categories. The sensitivity analysis showed how such a conclusion may be mitigated by considering different electricity mixes and maintenance dredging working cycles
Techno-economic assessment of the innovative ejectors plant technology for sediment management in harbours
Full text linkPurpose: The paper aims to show the monitoring results of an innovative technology, the ejectors plant, tested in the MARINAPLAN PLUS LIFE project framework for sustainable sediment management in harbours. Materials and methods: A monitoring plan has been designed to evaluate the technical, economic and environmental impact of the ejectors plant demonstrator for 15 months, located in Cervia (Italy). In particular, the demonstrator’s effectiveness and efficiency have been assessed to determine the yearly operation and maintenance costs. Results and discussion: The techno-economic analysis shows promising results in terms of efficacy and efficiency of the ejectors plant. The ejectors plant guaranteed navigability for the whole period of operation with a yearly cost reduction compared with traditional dredging. Conclusions: The innovative technology promoted by the MARINAPLAN PLUS LIFE project is a promising solution to manage sedimentation in harbours through a cost-effective and a low environmental impact technology. The monitoring actions validated the technology fully and demonstrated its efficacy and sustainability, highlighting the further improvements needed
A preliminary assessment of the potential of low percentage green hydrogen blending in the Italian Natural Gas Network
Full text linkThe growing rate of electricity generation from renewables is leading to new operational and management issues on the power grid because the electricity generated exceeds local requirements and the transportation or storage capacities are inadequate. An interesting option that is under investigation by several years is the opportunity to use the renewable electricity surplus to power electrolyzers that split water into its component parts, with the hydrogen being directly injected into natural gas pipelines for both storage and transportation. This innovative approach merges together the concepts of (i) renewable power-to-hydrogen (P2H) and of (ii) hydrogen blending into natural gas networks. The combination of renewable P2H and hydrogen blending into natural gas networks has a huge potential in terms of environmental and social benefits, but it is still facing several barriers that are technological, economic, legislative. In the framework of the new hydrogen strategy for a climate-neutral Europe, Member States should design a roadmap moving towards a hydrogen ecosystem by 2050. The blending of “green hydrogen”, that is hydrogen produced by renewable sources, in the natural gas network at a limited percentage is a key element to enable hydrogen production in a preliminary and transitional phase. Therefore, it is urgent to evaluate at the same time (i) the potential of green hydrogen blending at low percentage (up to 10%) and (ii) the maximum P2H capacity compatible with low percentage blending. The paper aims to preliminary assess the green hydrogen blending potential into the Italian natural gas network as a tool for policy makers, grid and networks managers and energy planners
Mitigation of pollutant emissions from residential biomass boilers
No full textThe Ecodesign and Energy Labelling Regulations for solid fuel boilers was published in 2015. The regulations establish minimum requirements and an energy labelling scheme. In particular, the regulations foresee the achievement of higher energy conversion efficiency and stringent limits about the emissions of particulate matter, carbon monoxide, organic gaseous carbon and NOx. The main novelty of the regulations is that also small size biomass boilers are covered. So, residential biomass boilers need to be redesigned, adapted and implemented to reach the ambitious target set by the European Commission. Due to the inhomogeneous, anisotropic and morphologically irregular characteristics of biomass, the combustion temperature is a difficult parameter to be controlled in biomass boilers, especially in residential systems, which are usually equipped with no or poor control devices. The result is a real combustion condition that is locally different from the theoretical one identified in the design phase. The paper focuses into two different approaches that can be applied to comply with the higher performances and lower emissions requested for residential biomass boilers. The first approach involves the combustion process: a simplified model for the combustion process of solid biomass is described to analyze and to compare the effect of different options for combustion efficiency increasing. The second approach addresses the loading procedure into a residential biomass boiler in order to avoid the risk of dioxins formation. The model application clearly shows that the size and shape of the biomass pellet can be used as a parameter to better control the combustion process over the time. A further study is needed to evaluate how the adoption of non-invasive plant re-vamping (like partial flue gas recirculation) can impact on the temperature and the air-to-biomass distribution in the combustion chamber
Green hydrogen valleys: a preliminary case study for the industrial area of Ravenna
Full text linkIn November 2020 Italian government released two drafts concerning a research and innovation roadmap and a national strategy about green hydrogen. A general target of 2% for the green hydrogen penetration in the Italian energy market is foreseen by 2030, corresponding to 0.7 million tons of green hydrogen production per year. Since no green hydrogen plants exist at industrial scale in Italy, a challenging strategy is necessary to achieve the expected target. To date, investors are discouraged from entering the market due to the existing barriers. However, applying and replicating the so-called “hydrogen valleys” concept represents a possible way to approach the short-medium term green hydrogen strategy. Since they are “regional ecosystems [...] developed relying on local production of hydrogen based on decentralized renewable energy production and local demand, transported over short distances”, new hydrogen valley projects would be characterized by lower and decentralized production as well as reduced transportation costs, thus potentially representing a more attractive investment. However, the techno-economic attractiveness of the project has to be assessed to justify the investment. Therefore, the paper describes a preliminary case study for a green hydrogen valley located in the industrial area of Ravenna. After a short introduction of the hydrogen valley concept, the paper shows the obtained results for a scenario-based techno-economic analysis concerning the realization of a hydrogen valley in
the industrial area of Ravenna
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