Search

Your search keyword '"Contino, Francesco"' showing total 647 results
Start Over Author "Contino, Francesco"
647 results on '"Contino, Francesco"'

2. The energy return on investment of whole energy systems: application to Belgium

Author

Dumas, Jonathan, Dubois, Antoine, Thiran, Paolo, Jacques, Pierre, Contino, Francesco, Cornélusse, Bertrand, and Limpens, Gauthier

Subjects
Electrical Engineering and Systems Science - Systems and Control
Abstract

Planning the defossilization of energy systems by facilitating high penetration of renewables and maintaining access to abundant and affordable primary energy resources is a nontrivial multi-objective problem. However, so far, most long-term policies to decrease the carbon footprint of our societies consider the cost of the system as the leading indicator in the energy system models. This paper is the first to develop a novel approach by adding the energy return on investment (EROI) to a whole energy system optimization model. We built the database with all EROI technologies and resources considered. In addition, moving away from fossil-based to carbon-neutral energy systems raises the issue of the uncertainty of low-carbon technologies and resource data. Thus, we conducted a global sensitivity analysis to identify the main parameters driving the variations in the EROI of the system. This novel approach can be applied to any energy system, and we use a real-world case study to illustrate the model: the 2035 Belgian energy system for several greenhouse gas emissions targets. The main results are threefold: (i) the EROI of the system decreases from 8.9 to 3.9 when greenhouse gas emissions are reduced by 5; (ii) the renewable fuels - mainly imported renewable gas - represent the largest share of the system primary energy mix; (iii) in the sensitivity analysis, the renewable fuels drive 67% of the variation of the EROI of the system for low greenhouse gas emissions scenarios. The decrease in the EROI raises questions about meeting the climate targets without adverse socio-economic impact. Most countries rely massively on fossil fuels, and they could encounter an EROI decline when shifting to carbon neutrality. Thus, this study demonstrates the importance of considering other criteria, such as EROI, in energy system models., Comment: Revised version of the paper submitted to Biophysical Economics and Sustainability for a second round of review

Published
2022
Full Text
View/download PDF

15. Influence of impurities on the use of Fe-based powder as sustainable fuel.

Author

Choisez, Laurine, Van Ende, Marie-Aline, Bruyr, Zakarie, Contino, Francesco, and Jacques, Pascal J.

Subjects
CLEAN energy, SUSTAINABILITY, FLUIDIZED bed reactors, METAL-base fuel, ENERGY development, FLAME temperature
Abstract

Sustainable energy production, inherently transient and non-uniformly distributed around the world, requires the rapid development of sustainable energy storage technologies. Recently, pure iron powder was proposed as a high-energy density carrier. While promising, challenges are faced, such as nanoparticle emissions, micro-explosions or cavitation. In this work, a screening of the impact of the most common impurities in iron sources on these mechanisms was conducted through purely thermodynamic simulations. Two idealized models were considered to obtain a range of plausible flame temperatures and emitted gases when considering a purely diffusive regime in standard conditions and stoichiometric air–fuel mixture. The flame temperature and iron evaporation are increasing with the specific energy. A strong evaporation of C, S, Mo, Cu and P is also expected. Most impurities are predicted to decrease cavitation, except for Mn and MnO. The regeneration process by hydrogen-based direct reduction in fluidized bed reactors is also discussed. MgO and CaO are the most promising additions in terms of reducing nanoparticles and porosities, as well as to improve the fluidization and reduction kinetics of the combusted products. The potential of Fe powder as sustainable fuel, already very promising, could be further improved by the addition of selectively chosen impurities. This article is part of the discussion meeting issue 'Sustainable metals: science and systems'. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

32. Techno-economic and resource assessment of electrolytic hydrogen and ammonia production

Author

Parente, Alessandro, Contino, Francesco, Fisette, Paul, Hendrick, Patrick, Gabrielli, Paolo, Moret, Stefano, Jeanmart, Hervé, Tonelli, Davide, Parente, Alessandro, Contino, Francesco, Fisette, Paul, Hendrick, Patrick, Gabrielli, Paolo, Moret, Stefano, Jeanmart, Hervé, and Tonelli, Davide

Abstract

The summers of 2020 and 2022 have represented two crossroads in the expectations around the role of hydrogen in the European energy system, setting a target of low-carbon hydrogen supply by 2030 more than twofold compared to the current carbon-intensive levels. While one half of the European supply is planned to be domestically produced within Europe, the other half is envisioned to be sourced from international markets. Projections for low-carbon hydrogen demand in Europe by 2050 range from half the current carbon-intensive demand level to a tenfold increase. Globally, the expected demand for low-carbon hydrogen in 2050 varies from equaling the current carbon-intensive demand level to a sevenfold increase. Factors affecting the scaling of low-carbon hydrogen supply are diverse and vary from the need to enhance the readiness of emerging production technologies to the adoption of mature technologies which lack an economy of scale. Different dynamics surround the hydrogen demand in 2050. Currently, hydrogen is mainly produced and consumed in production plants to refine hydrocarbons, or to produce ammonia and methanol. Current trade mainly concerns the fossil fuels used for its production. In the effort of achieving the net-zero target, hydrogen's role is predicted to extend to demand sectors where it's never been deployed on a large scale and where direct electrification faces limitations, such as heavy-duty transport, aviation, shipping, steel production, and industrial heat generation for the manufacturing of cement and other industrial products. The use of hydrogen relies on the presence of infrastructure to facilitate its transportation between production sites and demand points. Due to hydrogen's low volumetric energy density and high volatility, its derived carriers, i.e. ammonia, methanol, or synthetic hydrocarbons, might be preferred for its transport and as molecules for its final use. The primary goal of this research has been to quantify the hydrogen demand, Doctorat en Sciences de l'ingénieur et technologie, info:eu-repo/semantics/nonPublished

Published
2024

33. Experimental and numerical investigation of methane combustion in a HCCI engine under enriched oxygen conditions

Author

Spanò, S., Savarese, Matteo, Parente, Alessandro, Contino, Francesco, Jeanmart, Hervé, Spanò, S., Savarese, Matteo, Parente, Alessandro, Contino, Francesco, and Jeanmart, Hervé

Abstract

The challenge in the energy transition lies in the intermittent nature of renewable energy, requiring the development of effective storage methods. E-fuels are considered a promising solution, with potential applications to Homogeneous Charge Compression Ignition (HCCI) engines known for their high thermal efficiency and low nitrogen oxide emissions. However, HCCI engines face limitations such as low power density and a narrow operating range. To overcome these issues, oxygen-enriched combustion is proposed, aiming at enhancing the mixture reactivity and expanding the operating range by decreasing the intake temperature. As the potential of the expansion of the operating range has never been investigated, we performed an experimental campaign using a methane-fuelled HCCI engine at variable oxygen fractions in the oxidizer. To further elucidate the effects of oxy-fuel combustion, we also performed a kinetic analysis of the reactions driving the combustion behaviour. It has been experimentally found that increasing the oxygen content in the mixture, up to 90%, has a significant potential to decrease the needed intake temperature (up to 70 °C) of the charge to keep the Maximum Pressure Rise Rate (MPRR) below the safety threshold of 8 bar/CAD. Despite the notable IMEP increase achieved, operating the engine at high oxygen content presents significant technical challenges. Therefore, to make HCCI engines competitive with other combustion modes, it is essential to combine oxygen enrichment with additional power density enhancement techniques. The kinetic analysis has highlighted that the mixture is less sensitive to intake temperature changes at higher oxygen percentages (above 50%) and that the rates of the main reactions involved in methane and OH consumption are highly enhanced by oxygen addition., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2024

37. Comprehensive Analyses on the Influential Factors in Supersonic Combustion Simulation Using Dynamic Adaptive Chemistry Method.

Author

Wu, Kun, Contino, Francesco, and Fan, Xuejun

Subjects
LARGE eddy simulation models, COMBUSTION kinetics, COMBUSTION, FACTOR analysis, REACTIVE flow, DYNAMIC simulation
Abstract

To overcome the major challenge of reactive flow simulation for chemical kinetics dominated flame dynamics in supersonic combustion, on-the-fly mechanism reduction for high fidelity simulation of scramjet becomes mandatory. For dynamic adaptive chemistry (DAC) methodology, there are three major factors controlling the accuracy and efficiency of the overall simulation, namely, the mechanism reduction method, error threshold value $${\varepsilon _{DAC}}$$ ε DAC , and search initiating species (SIS). In the present work, systematic investigations of the three influential factors were conducted for large eddy simulation of ethylene-fueled supersonic combustion within a unified DAC framework. The results show that all the four mechanism reduction methods, i.e., DRG, DRGEP, PFA, and DAC-L, are adequate for the combustor's global performance prediction regarding the wall pressure, stable combustion productions, and temperature. However, for intricate flame stabilization characteristics, the DRG, DRGEP, and DAC-L methods yield comparable prediction accuracy in radical distributions, whereas the PFA method leads to relatively large discrepancies compared to direct integration with the detailed mechanism. The DRGEP method obtains the best balance between numerical accuracy and computational efficiency among the four methods, while the PFA method is the most computationally demanding one. Regarding the mechanism reduction error threshold value, the relative errors in physical property predictions increase as the relaxation of the error threshold value. And the comparative study suggests that the $${\varepsilon _{DAC}}$$ ε DAC should not exceed $${10^{- 4}}$$ 10 − 4 for high fidelity simulations of supersonic combustion. Furthermore, the stable species combination, namely, fuel, O2, and N2 incurs larger relative errors in radical mass fraction prediction than the combination including fuel and intermediate species HO2 and CO. Nevertheless, the latter is less computationally efficient than the former as it requires 15% more CPU time to solve the stiff ODE system of the resultant skeletal mechanism. It should be noted that the computational overheads for mechanism reduction under various $${\varepsilon _{DAC}}$$ ε DAC values and SIS combinations are almost the same, and the overall computational efficiency is mainly determined by the CPU time for solving the stiff ODE system of the size-reduced skeletal mechanisms. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results