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Manceau J.C.,Bureau de Recherches Géologiques et Minières | Tremosa J.,Bureau de Recherches Géologiques et Minières | Audigane P.,Bureau de Recherches Géologiques et Minières | Claret F.,Bureau de Recherches Géologiques et Minières | And 7 more authors.
Energy Procedia | Year: 2014

In this study, we present a new experiment for following the evolution of the well integrity over time due to different changes in well conditions (pressure, temperature and fluids in contact with the well) in the context of CO2 geological storage. A small section of a wellbore is reproduced in the Opalinus Clay of the underground rock laboratory of Mont-Terri, Switzerland (caprock-like formation) at scale 1:1. This system has been characterized hydraulically and geochemically during three periods: Initial state, after an increase in the well temperature and after replacing the fluid by pore water with dissolved CO2. The characterization of the system includes both performing hydro-tests to quantify the hydraulic properties of the well and their evolution over time, and sampling the fluids to analyze the geochemical composition and changes. The results presented in this study confirm the ability of the chosen design to estimate the evolution of the well integrity over time. © 2014 The Authors. Published by Elsevier Ltd.


Nouvel R.,Stuttgart University of Applied Sciences | Bahu J.-M.,EIFER | Kaden R.,TU Munich | Kaempf J.,Ecole Polytechnique Federale de Lausanne | And 6 more authors.
14th International Conference of IBPSA - Building Simulation 2015, BS 2015, Conference Proceedings | Year: 2015

No widely applicable open information model standard exists until now for large-scale Urban Energy Modelling. Although different data models have been developed for different urban energy tools, they do not offer possibilities of interoperability and exchange between the stakeholders, tools and expert fields. To address this issue, an international group of urban energy simulation developers and users is developing since May 2014 an Application Domain Extension (ADE) Energy for the open urban information model CityGML. This paper introduces the Energy ADE developed and tested by this international urban energy group. Goals, requirements and the modular structure of the CityGML extension are described in detail.


Manceau J.C.,Bureau de Recherches Géologiques et Minières | Audigane P.,Bureau de Recherches Géologiques et Minières | Claret F.,Bureau de Recherches Géologiques et Minières | Parmentier M.,Bureau de Recherches Géologiques et Minières | And 13 more authors.
Energy Procedia | Year: 2013

Wells drilled through low-permeable caprock are potential connections between the CO2 storage reservoir and overlying sensitive targets like aquifers and targets located at the surface. The wellbore integrity can be compromised due to in situ operations, including drilling, completion, operations and abandonment or to geochemical degradation of the caprock-cement-casing system. We present here an experimental set-up in the underground rock laboratory of Mont-Terri (St Ursanne, canton of Jura, Switzerland): The drilling and well completion in the laboratory will be done in the aim of reconstructing interfaces between the caprock, the cement and the casing steel that would be close to the ones observed in situ. These well features will then be dipped within a CO2 stream, during a given time period before a final over-coring. Such an experiment should provide new insights on the quality of bounding between casing/cement/clay interfaces and its evolution due to geochemical reactions. In parallel, a modeling effort is performed focused on both geochemical and transport aspects of the interactions between the fluids and the well compartments.


Ibrahim M.,Laboratory of Mathematics of Besancon | Ibrahim M.,University of Franche Comte | Antoni U.,EIFER | Steiner N.Y.,University of Franche Comte | And 6 more authors.
Energy Procedia | Year: 2015

In order to exploit all the benefits from the Proton Exchange Membrane Fuel Cell (PEMFC) technology and to gain a deeper understanding of operating faults during fuel cell operations, Investigation of the origins of faults is necessary. In this work, a diagnosis approach consisting of a method using signal-based pattern recognition is proposed. It is aimed at a minimization of efforts and costs in acquisition and evaluation of data for diagnostic purposes. All information needed to locate the faults is drawn from the recorded fuel cell output voltage, since certain phenomena leave characteristic patterns in the voltage signal. A signal analysis tool, namely the Wavelet Transform (WT), is employed to identify different patterns or faults signatures. The approach has been applied to voltage data recorded on a PEMFC suffering from dysfunctions related to inappropriate humidity levels inside the cell (two different faults are simulated: flooding and drying out). Characteristic features in the output voltage signals were outlined, so a distinction of several states of health was accomplished. The results show the efficiency of the proposed approach, and the WT can be considered as a reliable method to localize the dysfunctions. A comparison between the Discrete Wavelet Transform (DWT) and the Continuous Wavelet Transform (DWT) has shown that the DWT is more efficient in detecting and localizing faults in fuel cells. © 2015 The Authors. Published by Elsevier Ltd.


Fichet V.,EIFER | Kanniche M.,Électricité de France | Plion P.,Électricité de France | Gicquel O.,École Centrale Paris
Fuel | Year: 2010

The numerical prediction of NOx emissions from gas turbines is addressed in this paper. Generated from Computational Fluid Dynamics (CFD), a Reactor Network (RN) is defined to model the NOx formation with a detailed chemistry. An optimized procedure is proposed to split the reactive flow field into homogeneous zones considered as Perfectly Stirred Reactors (PSR). Once connected together, they result in a Chemical Reactor Network (CRN) that yields a detailed composition regarding species and temperature in the combustion chamber. Sensitivity studies are then performed to estimate the influence of air humidity and gas turbine load on NOx predictions. The NOx emissions predicted are in good agreement with the measured data in terms of levels and trends for the case studied (a gas turbine flame tube fed with natural gas and functioning at a pressure of 15 bar). Finally, the RN methodology has shown to be efficient estimating accurately NOx emissions with a short response time (few minutes) and small CPU requirements. © 2010 Elsevier Ltd. All rights reserved.


Grimaud A.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Bassat J.-M.,EIfER | Mauvy F.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Pollet M.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | And 3 more authors.
Journal of Materials Chemistry A | Year: 2014

PrBaCo2-xFexO5+δ solid solution is investigated in order to understand the Oxygen Reduction Reaction (ORR) and water formation occurring at the H+-SOFC cathode. Careful attention is paid to the study of the physical properties as a function of composition by Thermogravimetry Analysis (TGA), Mössbauer spectroscopy, electrical conductivity and Seebeck coefficient measurements, with the aim to establish the correlation existing with the ORR activity for these Mixed Ionic Electronic Conductors (MIEC). The oxygen diffusion coefficients are determined by Electrical Conductivity Relaxation (ECR) and Isotopic Exchange Depth Profile (IEDP) coupled with Secondary Ion Mass Spectroscopy (SIMS) methods. An electrochemical study is then carried out and shows that the amount of oxygen vacancies is the most influential parameter. Indeed, it allows some hydration of PrBaCo2O5+δ oxide and the formation of protonic defects that can induce protonic diffusivity in these MIEC oxides. © The Royal Society of Chemistry.


Grimaud A.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Mauvy F.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Bassat J.M.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Fourcade S.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | And 3 more authors.
Journal of the Electrochemical Society | Year: 2012

Four mixed ionic-electronic conducting (MIEC) perovskite-related oxides were studied as potential H +-SOFC cathode materials: La 0.6Sr 0.4Fe 0.8Co 0.2O 3-δ, Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3-δ, PrBaCo 2O 5 and Pr 2NiO 4+δ. Their hydration properties were measured by TGA: Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3-δ shows the largest water uptake. Their electrochemical performances were characterized using BaCe 0.9Y 0.1O 3-δ as electrolyte; polarization resistances as low as 0.5 cm 2 were found at 600C, for PrBaCo 2O 5 and Pr 2NiO 4+δ. The rate determining steps of the oxygen reduction reaction were determined on the basis of electrochemical studies performed as a function of pH 2O, in air. Proton transfer and water release appear to be the rate determining steps for Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3-δ, PrBaCo 2O 5 and Pr 2NiO 4+δ. No rate determining step involving proton was found for La 0.6Sr 0.4Fe 0.8Co 0.2O 3-δ. On the basis of this study, one can suggest that Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3-δ, PrBaCo 2O 5 and Pr 2NiO 4+δ show some protonic conduction as well as oxide diffusivity and can be labeled Triple Conducting (e-O 2-H +) Oxides, so-called TCO. © 2012 The Electrochemical Society.


Grimaud A.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Mauvy F.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Marc Bassat J.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | Fourcade S.,CNRS Laboratory of Condensed Matter Chemistry, Bordeaux | And 2 more authors.
Journal of Materials Chemistry | Year: 2012

The result of the substitution of Pr 3+ by Sr 2+ in the 214 Ruddlesden-Popper Pr 2NiO 4+δ material was studied with regard to its electrochemical properties as a H +-SOFC cathode. Structural characterizations as well as physical properties of the Pr 2-xSr xNiO 4+δ compounds (x ≤ 0.50), in particular hydration as a function of water partial pressure, have shown that oxygen over-stoichiometry and oxygen exchange with atmosphere decrease with increasing x, which has been correlated with the stabilization of the 214 structure by Sr 2+ substitution. Electrochemical studies on the oxygen reduction versus hydration have allowed determination of the rate determining steps of the formation of water and evidence the role of protons in Pr 2NiO 4+δ in contrast to Pr 2-xSr xNiO 4+δ oxides. It has been concluded that triple mixed conductivity (i.e. protonic, ionic as well as electronic conductivities) exists in this nickelate Pr 2NiO 4+δ. In addition, there was evidence for strong correlation between the insertion of protonic defects and additional oxygen in the interstitial position of Pr 2NiO 4+δ. © 2012 The Royal Society of Chemistry.


Loffler M.K.,EIFER | Griessbaum N.,EIFER
International Journal of Refrigeration | Year: 2014

Heat exchangers with phase-change achieve minimal dissipation when there is only a small temperature difference between the inlet and the outlet on the side of the sensible heat transfer medium. However, this does not usually occur in applications where these heat exchangers are typically used. In order to overcome this issue, an innovative prototype heat pump was realised. The heat pump was equipped with switchable storage devices to adapt the high temperature difference of the application to small temperature differences in the condenser. This way, the dissipation in the condenser was minimised, which led to COP increases by reducing the required mean pressure in the condenser. The use of storage devices resulted in measured efficiency improvements of 10%-50% in the prototype. With the described set-up, it is possible to approach the maximal thermodynamically possible COP, which makes an adaptation of the theoretical assessment of heat pumps necessary. © 2014 Elsevier Ltd and IIR.


Marrony M.,EIFER | Ancelin M.,EIFER | Lefevre G.,EIFER | Dailly J.,EIFER
Solid State Ionics | Year: 2015

Despite significant progress in terms of electrical performances and reliability, Protonic Ceramic Cell (PCC) technology faces too many technical hurdles concerning the validation of suitable processes for making large sized cells. Thus, the wet chemical techniques have been evaluated to the preparation of complete protonic ceramic cells from laboratory to industrial scales. According to results, the combination of tape-casting/screen-printing techniques is suitable for the elaboration of larger size planar hydrogen electrode supported PCC up to 50 cm2. Using BSCF-based air electrodes, electrochemical performances of a 20 cm2-size BaCeZrY-PCC based cell have been reached to 0.15 W/cm2 at 600°C and stable during few tens of hours without electrical degradation. © 2015 Elsevier B.V. All rights reserved.

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