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Électricité de France S.A. is a French electric utility company, largely owned by the French government. Headquartered in Paris, France, with €65.2 billion in revenues in 2010, EDF operates a diverse portfolio of 120,000+ megawatts of generation capacity in Europe, South America, North America, Asia, the Middle East and Africa.EDF is the world's largest producer of electricity. In 2011, it produced 22% of the European Union's electricity, primarily from nuclear power:nuclear: 84.7%;renewable energy: 8.3% ;gas: 2.7%;charcoal: 2.7%;fuel: 1.2%;other: 0.4%.Its 58 active nuclear reactors are spread out over 20 sites . They comprise 34 reactors of 900 MWe, 20 reactors of 1300 MWe, and 4 reactors of 1450 MWe, all PWRs. Wikipedia.

A concept of coal-fired power plant built around a supercritical CO2 Brayton power cycle and 90% post-combustion CO2 capture have been designed. The power cycle has been adapted to the coal-fired boiler thermal output, this boiler has been roughly designed in order to assess the power cycle pressure drop and its cost, an adapted CO2 capture process has been designed and finally the overall heat integration of the power plant has been proposed. Due to the high complexity of such as plant, this paper does not intend to provide definitive evaluation of the concept but to explore its potential.A coal power plant with CO2 power cycle without carbon capture could achieve a net efficiency of 50% (LHV) with a maximal temperature and pressure of 620 °C and 300 bar, these performances has to be validated but the first results on pilot plant are encouraging. The CO2 capture process use monoethanolamine as solvent and is equipped with vapor recompression systems in order to reduce the heat needed from the CO2 cycle. It achieves around 2.2 GJ/tCO2 of specific boiler duty with 145 kWh/tCO2 of electrical auxiliary consumption including compression to 110 bar. The energetic evaluation of the overall power plant carried out highlights the promising potential of CO2 supercritical cycle. A net power plant efficiency of 41.3% (LHV), with carbon capture and CO2 compression to 110 bar, seem to be achievable with available or close-to-available equipment.A technical-economic evaluation of the designed power plant has been performed. It shows a levelized cost of electricity reduction of 15%, and a cost of avoided CO2 reduction of 45%, without transport and storage, compared to a reference supercritical coal-fired power plant equipped with standard carbon capture process. © 2012 Elsevier Ltd. Source

Sanahuja J.,Electricite de France
International Journal of Solids and Structures | Year: 2013

The correspondence principle is widely used to estimate the effective behaviour of non ageing linear viscoelastic composites, as it allows to take advantage of homogenization approaches originally developed in the elastic framework. However, this principle is no longer valid when the phases exhibit ageing. The approach proposed in this paper overcomes this limitation. Operating in the time domain, it allows to use homogenization of random media on composites made up of isotropic ageing linear viscoelastic phases. Several homogenization schemes are revisited to take into account information on morphology, namely the dilute, Mori Tanaka and self-consistent schemes with spherical shapes. This approach is validated against results obtained from either analytical or numerical computations. It is found to be efficient on nowadays computers: the effective relaxation tensor of a matrix-inclusions composite can be obtained in less than one second, whereas numerical FEM homogenization takes more than twelve minutes on a very coarse mesh. © 2013 Elsevier Ltd. All rights reserved. Source

Henry C.,Szewalski Institute of Fluid Flow Machinery | Minier J.-P.,Electricite de France
Progress in Energy and Combustion Science | Year: 2014

This article deals with the resuspension phenomenon whereby particles adhering on a wall surface can be re-entrained by a flowing fluid. This is an area where significant progress has been achieved over the last years from an experimental, theoretical and numerical point of view. A first purpose of the present work is to report on the advances that have clarified our understanding of the physics of particle resuspension. It will be seen that new pictures have emerged about the physical processes involved in particle resuspension and, correspondingly, that new models have been proposed. A second purpose of the review is to put forward a general framework that allows both experimental analysis and new modelling ideas to be developed in terms of the fundamental interactions at play. These interactions are made up by the particle-fluid, particle-surface and particle-particle forces which are, in turn, related to the three specific fields of fluid dynamics, interface chemistry and surface roughness. Such a separation is helpful to highlight the actual physical processes while emphasising their relative importance in different situations and to provide useful guidelines for the necessary modelling efforts. In particular, it is stressed that new models which capture particle motion along a wall and simulate the complete particle dynamics represent an improvement over more classical static approaches. It is proposed that these new approaches be pursued and brought to higher levels of maturity. In this paper, attention is first focussed on the case where only a single layer of particles is sticking on the surface and, thus, can be re-entrained. A detailed review of the experimental works brings out the essential mechanisms and particle resuspension is shown to result from a balance between particle-fluid interactions and particle-surface interactions influenced by surface heterogeneities (roughness). The numerical models which have been proposed are then thoroughly discussed with respect to a new hierarchy of modelling approaches which is introduced. The present paper also outlines the mechanisms of multilayer particle resuspension which is still an open subject and where our present understanding remains preliminary. In this situation, resuspension is shown to be also governed by particle-fluid and particle-surface interactions but with the addition of particle-particle interactions (through cohesion forces or impaction). Finally, suggestions about the areas that still need to be addressed as well as about the issues that remain to be improved are addressed. © 2014 Elsevier Ltd. All rights reserved. Source

Agency: Cordis | Branch: H2020 | Program: IA | Phase: LCE-07-2014 | Award Amount: 19.12M | Year: 2015

Four major Distribution System Operators (in Italy, France, Spain and Sweden) with smart metering infrastructure in place, associated with electricity retailers, aggregators, software providers, research organizations and one large consumer, propose five large-scale demonstrations to show that the deployment of novel services in the electricity retail markets (ranging from advanced monitoring to local energy control, and flexibility services) can be accelerated thanks to an open European Market Place for standardized interactions among all the electricity stakeholders, opening up the energy market also to new players at EU level. The proposed virtual environment will empower real customers with higher quality and quantity of information on their energy consumptions (and generation in case of prosumers), addressing more efficient energy behaviours and usage as through advanced energy monitoring and control services. Accessibility of metering data, close to real time, made available by DSOs in a standardized and non-discriminatory way to all the players of electricity retail markets (e.g. electricity retailers, aggregators, ESCOs and end consumers), will facilitate the emergence of new markets for energy services, enhancing competitiveness and encouraging the entry of new players, benefitting the customers. Economic models of these new services will be proposed and assessed. Based on the five demonstrations, while connecting with parallel projects funded at EU or national levels on novel services provision, the dissemination activities will support the preparation of the Market Place exploitation strategies, as well as the promotion of the use cases tested during the demonstration activities.

Minier J.-P.,Electricite de France
Progress in Energy and Combustion Science | Year: 2015

The purpose of the present paper is to provide a comprehensive account of Lagrangian stochastic methods for polydisperse two-phase reactive flows. In this work, the emphasis is put on the description of the dispersed phase and on one-particle probabilistic approaches to general non-homogeneous flows. This is a domain where significant progress has been achieved in the last decade and reporting on these advances brings out the current status of Lagrangian stochastic methods. A first objective of this paper is to recall the main aspects of the existing theoretical framework where developments are shown to be set in. A second objective is to clarify the physics contained in present stochastic models. To that effect, the presentation of the main aspects of the reference Langevin model as well as the detailed analysis of several applications covering a range of practical concerns reveal the actual possibilities of these modeling approaches. A third objective is to report on recent developments that open possibilities for Lagrangian stochastic methods, including for example first steps toward structure-based models, hybrid numerical formulations as well as new accounts of particle-particle interactions. Building on these results, a formalism is introduced in the last section for the extension of Lagrangian stochastic methods to particle-laden turbulent flows where the fluid flow is calculated with a Large Eddy Simulation. Finally, the research areas where work is still needed are outlined. © 2015 Elsevier Ltd. All rights reserved. Source

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