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Aix-en-Provence, France

Darras C.,CNRS Environmental Sciences | Muselli M.,CNRS Environmental Sciences | Poggi P.,CNRS Environmental Sciences | Voyant C.,CNRS Environmental Sciences | And 3 more authors.
International Journal of Hydrogen Energy | Year: 2012

The MYRTE platform is one of the PEPITE project applications included in the PAN-H program of the French Research National Agency, under the reference ANR-07-PANH-012. This platform consists of a photovoltaic array, a fuel cell, an electrolyzer, tanks (H2, O2 and H2O), a thermal management system and electricity converters associated to various sub-systems. This article describes the platform's way of operating and specifically the photovoltaic output power fluctuations smoothing, with the trapezoid profile shape, using storage methodology. The used approach is consistent with the specifications of the call for tender of the French Energy Regulation Commission, in September, 2011. Note that during the simulations, we have used measured and not predicted meteorological data. The main result shown in this paper is that the platform is compatible with this operational mode based on the power fluctuations smoothing. However, to minimize the use of gas tanks, the power supply of trapezoid profile should come from the PV production rather than the fuels cells. A minimum part of 76% seems necessary to assure the smoothing all year round and to have an identical reservoirs state at the beginning and at the end of the year. © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source


Darras C.,CNRS Environmental Sciences | Thibault C.,CNRS Environmental Sciences | Muselli M.,CNRS Environmental Sciences | Poggi P.,CNRS Environmental Sciences | And 5 more authors.
International Journal of Hydrogen Energy | Year: 2010

This paper concerns the impacts of the meteorological data, the choice of the load profile, and the time simulation (1-11 years) on the energy flows and on the H2/O2/H2O storage sizing in a photovoltaic/fuel cell/electrolyzer hybrid system (PEPITE project). The simulations were computed with the ORIENTE software. 4 load profiles have been investigated (3 diurnal and one nocturnal) with an identical daily consumption (26 kWh). According to load profiles, the gap observed between the most favorable and the most disadvantageous years induces H2 storage variations rates between 45.5% and 55.3%. Furthermore, if we compare the most penalizing meteorological year with the sizing when we simulate several successive years, we also obtain variation rates (ration between the standard deviation and the corresponding averaged value) ranges from 24.4 to 37.9% for the 3 diurnal profiles. The nocturnal profile presents specific results because it is unsustainable. The main conclusion of this work is the great importance to consider several consecutive years of tilted irradiation data, 7 in our case, to size the H2/O2/H2O storages. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. Source


Kokoh K.B.,French National Center for Scientific Research | Mayousse E.,CEA Grenoble | Napporn T.W.,French National Center for Scientific Research | Servat K.,French National Center for Scientific Research | And 5 more authors.
International Journal of Hydrogen Energy | Year: 2014

Anode catalysts synthesized by the thermal decomposition method were used for splitting water in PEM electrolysis cells. Although the area resistance of the ternary anode materials increased, the Ti content in the ruthenium and iridium based catalysts have led to an energy consumption of 4.5 kWh/Nm 3(H2) at 60 C. The Membrane Electrode Assemblies have given information on the strong dependence of the membrane thickness. The crossover of hydrogen through Nafion®117 is two-fold lower than that measured in the presence of Nafion®115. Life testing was attempted with supplying the electrolyzer by solar power source. Importantly, the proton exchange membrane water electrolyzer (PEMWE) cell has involved a constant cell voltage at 1 A cm-2 over 800 h durability tests. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights. Source


Didierjean S.,University of Lorraine | Chenu A.,University of Lorraine | Geneston T.,HELION Hydrogen Power | Rakotondrainibe A.,HELION Hydrogen Power | And 4 more authors.
International Journal of Hydrogen Energy | Year: 2012

The transient response of proton exchange membrane fuel cells during start-up is an important issue for backup power systems which require a very short start-up time in order to limit the use of batteries during a blackout. The start-up procedure of a ten cells stack was studied: in the first stage the cathode channel initially filled with nitrogen was supplied with oxygen in open circuit then in the second stage it was connected to the load. The influences of the current time-profile (step or ramp), the cell voltage at the connection and the gas flow rates on the voltage variation were investigated. It was found that the voltage value during the filling of the cathode is not sufficient to determine which fraction of the cathode was filled with oxygen. In most cases, high oxygen flow rates allow reducing the start-up time of the stack. Furthermore, for fixed current density and stoichiometric coefficients it was found that a minimum start-up time exits. The analysis of transient response to current steps showed that around 70% of the maximum electrical power was available less than 2 s after the beginning of the start-up procedure. © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source


Didierjean S.,University of Lorraine | Lamibrac A.,University of Lorraine | Geneston T.,HELION Hydrogen Power | Rakotondrainibe A.,HELION Hydrogen Power | And 4 more authors.
International Journal of Hydrogen Energy | Year: 2012

The transient response of proton exchange membrane fuel cells during start-up is an important issue for backup power systems. These require a very short start-up time which limits the use of batteries during a blackout. In this study the fuel cell was initially inerted with nitrogen at the cathode and thus the start-up procedures occurred in two stages: gas supply in open-circuit and load connection. The influence of the current time-profile, the cell voltage at the connection and the gas flow rates on the voltage variation were investigated using a segmented fuel cell permitting the measurements of the internal local currents. We found that the voltage during the filling of the cathode is not sufficient to determine which fraction of the cathode was filled with oxygen. In the case of a step change in current, the start-up time decreases as the voltage at the moment the cell is connected increases. In response to a ramp, the asymptotic power value is reached quickly. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights. Source

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