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International audience; Windows are central in architecture and they play a significant role in the energy consumption of buildings, particularly in hot climates, where overheating is a critical issue. Innovative glazing technologies, like thermochromic (TC) glazing, could help to overcome those issues. This article aims to identify both the influence and the importance of thermochromic glazing parameters. A sensitivity analysis by means of moment-independent measure with Latin hypercube sampling has been used, taking the uncertainties of the parameters into account, as well as dynamic daylighting and thermal building simulations. The results allow us to put forward the most important set of factors that need to be carefully chosen to design low-energy buildings, with a comfort performance approach. The conclusion of this study provides further knowledge for designers about TC glazing in the early design stage of buildings, for several climates. It demonstrates that the glazing area has the greatest impact on the results, but also several key TC glazing parameters such as the solar or visible transmittance and the switching temperature.

International audience; Light pipes MLP (Mirrored Light Pipe) are used to transport and distribute daylight in dark areas remote of the traditional openings. It offers the advantage of minimizing the loss of light, while limiting the transmission of heat. They belong to the category of conveyors multiple specular reflections. Its purpose is for collecting, reflecting and focusing the sunlight with a roof dome arranged. This is then fed through a tube with highly reflective interior surfaces and distributed within the room with a diffuser. In recent decades, many authors have developed models to predict the performance of these devices based on various existing configurations. This variety of approach has led directly to a dispersion of the results of predicted performance of light pipes and the inconsistency with respect to the actual behavior of the device. The objective of this publication is to highlight the disparity of these models. A literature review of different approaches and a comparative analysis were carried out. The consistency of the theoretical results was evaluated from the experimentation in progress (real scale and real weather conditions). It results that the various selected models tend to overestimate or underestimate the actual phenomenon. The use of an experimental database has put forward the most efficient and promising model. The future prospects of our study that emerge are based primarily on the implementation of a new model for predicting the performance of light pipes.Les conduits de lumière de type MLP (Mirrored Light Pipe) permettent de transporter et de distribuer de la lumière naturelle dans des pièces sombres éloignées des ouvertures traditionnelles. Il offre l'avantage de réduire au minimum la perte de lumière, tout en limitant la transmission de chaleur. Ils font partie de la catégorie des convoyeurs à réflexion spéculaire multiple. Il s'agit de collecter, concentrer et dévier la lumière du soleil à l'aide d'un dôme placé en toiture. Celle-ci est ensuite acheminée à travers un tube aux parois hautement réfléchissantes puis diffusée au sein du local à l'aide d'un diffuseur. Au cours des dernières décennies, de nombreux auteurs ont établis des modèles de prédiction des performances de ces dispositifs tubulaires en fonction des diverses configurations existantes. Cette variété d'approche a eu pour conséquence directe une dispersion des résultats des performances des conduits de lumière et une incohérence par rapport aux performances réelles de ce dispositif. L'objectif de cette publication est de mettre en avant la disparité de ces modèles. Une étude bibliographique des différentes approches et une analyse comparative ont été réalisées. La cohérence des résultats théoriques a été évaluée à partir des données empiriques résultantes de l'expérimentation échelle 1:1 en condition météorologique réelle en cours. Il en résulte que les divers modèles sélectionnés ont tendance à surestimer ou sous-estimer le phénomène réel. L'utilisation d'une base de données expérimentales a permis de mettre en avant les plus performants et les plus prometteurs. Les perspectives futures de notre étude qui en ressortent se basent principalement sur la mise en place d'un nouveau modèle de prédiction des performances des conduits de lumière.

This Ph.D thesis focusses on energy control in buildings in order to reach high energetic performances by the use of passive means. One of the proposed solution is based on the use of Phase Change Materials (PCMs). Located into walls, PCMs allow to stock thermal energy into latent heat. The aim of the study is thus to put in evidence PCMs actual impacts on the thermal field of a building and its role as thermal insulation. For these considerations, a thermal model has been developed and validated. An experimental device has been set-up for the collection of data in field environment and for a human scale. The measurement sequence has been conducted at Reunion Island, for a hot and humid tropical climate. For the determination of the thermal behaviour of a commplex wall included PCMs, we proposed a generic model, able to predict many configurations. The model has been implemented in a multizone building simulation code (ISOLAB), for the prediction of wall temperature profiles and PCMs impact on the thermal comfort. Following a combined metholodogy, including modelling and experimentation for validation, we were able to validate the model for actual conditions and to evaluate the model's prediction accuracy., Cette thèse s'inscrit dans une démarche de maîtrise de l'énergie dans le secteur du bâtiment. Elle a pour but d'utiliser des solutions passives pour atteindre de hautes performances énergétiques. Une des solutions proposée, est l'utilisation de Matériaux à Changements de Phase (MCP) dans les parois. Les matériaux à formes stabilisée solide-liquide, sont utilisés pour stocker l'énergie thermique sous forme de chaleur latente. Le but de l'étude est de mettre en évidence l'impact réel des MCP en terme de complément d'isolation thermique et de proposer un modèle thermique pour prédire son impact sur le champ de température et par conséquent, sur le confort thermique. Une séquence expérimentale en environnement naturel et à grande échelle a été menée à l'île de La Réunion, où le climat est tropical et humide, avec un fort taux d'ensoleillement. Le rayonnement solaire étant important, il est nécessaire de minimiser les sollicitations solaires sur l'ensemble du bâtiment et en particulier la toiture, qui constitue la surface la plus exposée. La présence de lames d'airs au niveau de la toiture, qualifie celle-ci de complexe. Il est alors nécessaire de proposer une modélisation adaptée. Le modèle est couplé à un code de simulation thermique du bâtiment (ISOLAB) et permet de prédire d'une part, les profils de températures de chacune des surfaces constituant l'enveloppe du bâtiment, et d'autre part, d'évaluer l'impact des MCP sur le confort thermique pour différentes configurations. Selon une méthodologie, alliant Modélisation, Expérimentation et Validation (MEV), la démarche a permis de valider l'expérimentation dédiée et d'évaluer la capacité du modèle à prédire l'ensemble des données issues de l'expérimentation.

This Ph.D thesis focusses on energy control in buildings in order to reach high energetic performances by the use of passive means. One of the proposed solution is based on the use of Phase Change Materials (PCMs). Located into walls, PCMs allow to stock thermal energy into latent heat. The aim of the study is thus to put in evidence PCMs actual impacts on the thermal field of a building and its role as thermal insulation. For these considerations, a thermal model has been developed and validated. An experimental device has been set-up for the collection of data in field environment and for a human scale. The measurement sequence has been conducted at Reunion Island, for a hot and humid tropical climate. For the determination of the thermal behaviour of a complex wall included PCMs, we proposed a generic model, able to predict many configurations. The model has been implemented in a multizone building simulation code (ISOLAB), for the prediction of wall temperature profiles and PCMs impact on the thermal comfort. Following a combined metholodogy, including modelling and experimentation for validation, we were able to validate the model for actual conditions and to evaluate the model’s prediction accuracy.; Cette thèse s’inscrit dans une démarche de maîtrise de l’énergie dans le secteur du bâtiment.Elle a pour but d’utiliser des solutions passives pour atteindre de hautes performancesénergétiques. L’une des solutions proposées est l’utilisation de Matériaux à Changements dePhase (MCP) dans les parois. Les matériaux à formes stabilisées solide-liquide, sont utiliséspour stocker l’énergie thermique sous forme de chaleur latente. Le but de l’étude est de mettreen évidence l’impact réel des MCP en termes de complément d’isolation thermique et de proposerun modèle thermique pour prédire leurs impacts sur le champ de température et sur le confortthermique.Une séquence expérimentale en environnement naturel et à grande échelle a été menée àl’île de La Réunion, où le climat est tropical et humide, avec un fort taux d’ensoleillement. Lerayonnement solaire étant important, il est nécessaire de minimiser les sollicitations solaires surl’ensemble du bâtiment et en particulier la toiture, qui constitue la surface la plus exposée. Ilest alors nécessaire de proposer une modélisation adaptée, qui intègre à la fois les phénomènesphysiques mis en jeu mais également les éléments structurels selon l’état de l’art. Le modèle estcouplé à un code de simulation thermique du bâtiment (ISOLAB) et permet de prédire d’unepart les profils de températures de chacune des surfaces constituant l’enveloppe du bâtiment, etd’autre part d’évaluer l’impact des MCP sur le confort thermique pour différentes configurations.Selon une méthodologie alliant Modélisation, Expérimentation et Validation (MEV), la démarchea permis de valider l’expérimentation dédiée et d’évaluer la capacité du modèle à prédirel’ensemble des données issues des séquences expérimentales.

Available from: http://www.intechopen.com/books/evaporation-condensation-and-heat-transfer/heat-transfer-in-buildings-application-to-solar-air-collector-and-trombe-wall-design; International audience; The aim of this paper is to briefly recall heat transfer modes and explain their integration within a software dedicated to building simulation (CODYRUN). Detailed elements of the validation of this software are presented and two applications are finally discussed. One concerns the modeling of a flat plate air collector and the second focuses on the modeling of Trombe solar walls. In each case, detailed modeling of heat transfer allows precise understanding of thermal and energetic behavior of the studied structures. Recent decades have seen a proliferation of tools for building thermal simulation. These applications cover a wide spectrum from very simplified steady state models to dynamic simulation ones, including computational fluid dynamics modules (Clarke, 2001). These tools are widely available in design offices and engineering firms. They are often used for the design of HVAC systems and still subject to detailed research, particularly with respect to the integration of new fields (specific insulation materials, lighting, pollutants transport, etc.). Available from: http://www.intechopen.com/books/evaporation-condensation-and-heat-transfer/heat-transfer-in-buildings-application-to-solar-air-collector-and-trombe-wall-design

1.1 History of photovoltaic systems ... Photovoltaics is one of the leading chains of "sustainable development". Indeed, when one observes the development programs of energy systems in the countries or nations that move towards sustainable development, we find that the solar (and through it the production of energy through photovoltaics) represents the main axis of development. One might at first believe that knowledge of the photovoltaic effect is recent. In fact, we must go back to 1839 with the French physicist Edmund Becquerel who first discovered the photovoltaic effect. It was during the period between the second half of the 19th and the Second World War (1945) that scientific knowledge related to solar phenomena were mastered. Thus, in 1875, Werner von Siemens presented to the Academy of Sciences in Berlin an article on the photovoltaic effect in semiconductors and it was Albert Einstein who first was able to explain the photovoltaic principle, thereby won the Nobel Prize for Physics in 1923. After the Second World War, when the world gets in another war called "cold war" between the East Block in the West Block, the simmering conflict reached its apogee in the arms race and especially in the space conquest. The space industry is now rapidly finding new and innovative solutions that would power satellites into space. This was a boon for the photovoltaic sector and will help structure an industry. Thus, in 1954, with the developed of a high efficiency photovoltaic cell for the time (6%) and in 1958, the rise of the yield to 9% and above, VANGUARD, the first satellite equipped with photovoltaic cells was sent to the space. The oil shocks of the 1970s allowed the industry to begin its development in civilian applications in 1973 with the construction of the first house powered by solar cells at the University of Delaware. The next step was the construction of the first car equipped with a photovoltaic energy, which in 1983 covered a distance of 4000 km in Australia. Yet in 1980, while the industry is launched commercially, the following years have seen its development focus mainly on rural electrification as well as some isolated houses for professional use (refuges, measuring stations, etc.) and for many villages in developed countries. Since 1990, awareness of the phenomenon of global warming induced the development of the concept of sustainable development, with effect of boosting the photovoltaic and allows it to pass a critical level.