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Le Bourget du Lac, France

Amrouche B.,Renewable Energy Development Center Algeria | Le Pivert X.,French National Solar Energy Institute
Applied Energy | Year: 2014

When a part of the power is generated by grid connected photovoltaic installations, an effective global solar irradiation (GSI) forecasting tool becomes a must to ensure the quality and the security of the electrical grid. GSI forecasts allow the quantification of generated photovoltaic (PV) power and helps electrical grid operators anticipate problems related to the nature of PV power and the planning for adequate solutions and decisions. In this study, a new methodology for local forecasting of daily global horizontal irradiance (GHI) is proposed. This methodology is a combination of spatial modelling and artificial neural networks (ANNs) techniques. An ANN based model is developed to predict the local GHI based on daily weather forecasts provided by the US National Oceanic and Atmospheric Administration (NOAA) for four neighbouring locations. The methodology was tested for two locations; Le Bourget du Lac (45°38'44″N, 5°51'33″E), which is located in the French Alps and Cadarache (43°42'28″N, 05°46'31″E), which is located in the south of France. The model's forecasts were compared to measured data for the two locations and validation results indicate that the ANN-based method presented in this study can estimate daily GHI with satisfactory accuracy. © 2014 Elsevier Ltd. Source

Le Perchec J.,French National Solar Energy Institute
Optics Express | Year: 2012

We investigate the dual optical behaviour of a photonic grating interface presenting a more or less important index contrast, showing either efficient broadband reflectivity, either high transmittance within the same spectral window, depending on the direction of the incident light. This behaviour is reminiscent of a diode one and could find interesting applications. A typical example is given for thin crystalline silicon solar cells where the rear side is directly nano-textured to trap light without metal reflector (bifacial device), well compatible with an integration in a photovoltaic module. © 2012 Optical Society of America. Source

Sicurella F.,French National Center for Scientific Research | Evola G.,French National Center for Scientific Research | Wurtz E.,French National Solar Energy Institute
Energy and Buildings | Year: 2012

In recent years, the study of indoor environmental comfort during the warm season has been one of the most attractive and hard tasks for architects and energy designers. Nowadays, thanks to the available high-performance utilities, the dynamic energy simulation of a building is relatively easy. Nevertheless, since it should simultaneously account for thermal, visual and air quality issues, a global approach, often neglected, becomes necessary. In the present work, an approach based on simple indicators calculated on a statistical basis will be presented; it can be useful for the simultaneous evaluation of the indoor thermal and visual comfort on a more comprehensive perspective, and it can be applied in any building energy analysis where a comparison between different solutions or strategies is required. At the end of the paper this approach is tested on a simple case study in order to show how the approach can be used to evaluate the influence of the size and the typology of a window on indoor comfort. © 2012 Elsevier B.V. All rights reserved. Source

Baudrit M.,French National Solar Energy Institute | Algora C.,Technical University of Madrid
IEEE Transactions on Electron Devices | Year: 2010

Multijunction solar cells (MJCs) based on IIIV semiconductors constitute the state-of-the-art approach for high-efficiency solar energy conversion. These devices, consisting of a stack of various solar cells, are interconnected by tunnel diodes. Reliable simulations of the tunnel diode behavior are still a challenge for solar cell applications. In this paper, a complete description of the model implemented in Silvaco ATLAS is shown, demonstrating the importance of local and nonlocal trap-assisted tunneling. We also explain how the measured doping profile and the metalization-induced series resistance influence the behavior of the tunnel diodes. Finally, we detail the different components of the series resistance and show that this can help extract the experimental voltage drop experienced by an MJC due to the tunnel junction. The value of this intrinsic voltage is important for achieving high efficiencies at concentrations near 1000 suns. © 2006 IEEE. Source

Riffonneau Y.,Joseph Fourier University | Bacha S.,Joseph Fourier University | Barruel F.,French National Solar Energy Institute | Ploix S.,Grenoble Institute of Technology
IEEE Transactions on Sustainable Energy | Year: 2011

This paper presents an optimal power management mechanism for grid connected photovoltaic (PV) systems with storage. The objective is to help intensive penetration of PV production into the grid by proposing peak shaving service at the lowest cost. The structure of a power supervisor based on an optimal predictive power scheduling algorithm is proposed. Optimization is performed using Dynamic Programming and is compared with a simple ruled-based management. The particularity of this study remains first in the consideration of batteries ageing into the optimization process and second in the "day-ahead" approach of power management. Simulations and real conditions application are carried out over one exemplary day. In simulation, it points out that peak shaving is realized with the minimal cost, but especially that power fluctuations on the grid are reduced which matches with the initial objective of helping PV penetration into the grid. In real conditions, efficiency of the predictive schedule depends on accuracy of the forecasts, which leads to future works about optimal reactive power management. © 2011 IEEE. Source

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