Visual comfort conditions in school buildings are important to provide well-being, health and improving educational productivity. Considering benefits that visual comfort promotes, this research aimed to evaluate the daylight availability for two classrooms in a high school located in interior of Rio Grande do Sul, southern Brazil. The analysis was based on two methods. One of them considered in situ measurements of illuminance levels with datalogger during five days on April, June, August and December (twenty days of measurements), according to NBR 8995 Brazilian standard; the other considered the students momentary satisfaction with natural light quality through the application of questionnaires with face-to-face direct questions in one day for mentioned months. Further the artificial and natural lighting requirements according to RTQ-C Brazilian standard were verified. The natural light factor (CIN) was calculated based on internal and simultaneous external illuminances obtained through measurement with a manual luximeter. The method used to find CIN was based on NBR 15215-3 Brazilian standard. Taking into account measurement period the illuminance levels were higher than standard values stablished on NBR 8995 for the majority of measured points. The study also showed that the majority of students were satisfied with momentary light conditions available in classrooms. They reported problems with direct solar radiation on desks. The light system of analyzed classrooms did not satisfy the requirements of RTQ-C referring to automatic artificial light controls. The CIN coefficients presented high variability that demonstrates the regional daylight also presents heterogeneous conditions throughout the year. The main findings are the difficulty of defining a suitable method to measure external illuminances in situ, CIN references for specific Brazilians sky conditions and difficulty of measuring internal illuminances during long-range time due to high variability of regional cloudy and clear-sky conditions. / A condição de conforto visual, nas edificações, é importante para promover o bemestar, saúde e aumentar a produtividade. Levando em conta os benefícios que o conforto visual promove, esse trabalho teve como objetivo avaliar a disponibilidade de iluminação natural em duas salas de aula de uma instituição de ensino superior localizada no interior do RS. A avaliação foi feita usando dois métodos: medições in loco dos níveis de iluminância mantida, para cinco dias durante os meses de abril, junho, agosto e dezembro, totalizando vinte dias de medições, e tomando como referência para o nível de iluminância mantida o valor estabelecido na NBR 8995 e pela opinião dos usuários através de aplicação de questionário sobre sua percepção momentânea sobre as condições da iluminação natural, para quatro dias em cada um dos meses já citados. Além disso, foi verificada a satisfação dos requisitos específicos do RTQ-C aplicáveis à iluminação natural, e calculados os coeficientes de contribuição de iluminação natural, CIN, de acordo com a NBR 15.215-3, com medições externas de níveis de iluminância paralelas às medições internas. Os resultados demonstram, para as condições de céu e dias avaliados, que os níveis de iluminância mantida são bem superiores ao nível de iluminância mantida recomendada pela NBR 8995 na maioria dos pontos e dias de medições. Os usuários demonstraram, em sua maioria, satisfação momentânea com as condições de iluminação natural das salas, relatando problemas com o controle da incidência direta de radiação solar sobre mesas. As salas, para o sistema de iluminação, apenas não satisfazem ao requisito relativo ao desligamento automático de iluminação artificial, do RTQ-C. Considerando os valores de CIN obtidos, percebeuse sua variabilidade em relação às condições externas de céu. Com a realização dessa pesquisa foi possível perceber a dificuldade em encontrar procedimentos para medição de iluminâncias externas como apontado pela NBR 15.575, dificuldade em encontrar valores de CIN compatíveis com as condições de céu presentes no Brasil e dificuldade em medir as iluminâncias internas em períodos prolongados devido a grande variabilidade de céu presente na região da pesquisa.

The application of dynamic wind load on photovoltaic (PV) solar systems mounted on flat roofs influenced their structural behavior significantly. It is implied that when the PV solar system is exposed to extreme weather characteristics such as low temperatures, these might influence the load distribution along each layer of the solar panel, which is composed by multiple layers of different materials. Therefore, the high record of weather characteristics as one scenario in addition to the field experiment were designed to describe parametric structural behavior of PV solar system help to increase the precision of study. According to the mentioned procedures different parameters of weather characteristics measured with instrumentation at the site of PV panel installation at the University of Ottawa where the low temperature equal to -24.3° C and wind speed of 11.8 recorded. The mechanical and thermal properties of full-scale specimen and load application that computed based on weather record for every two minutes of January and February from northern side of specimen, introduced to FEM software SAP 2000. Moreover, the support structure and connection used to assemble real specimen considered in modeling with respect to average temperature equal to -7° C that caused to simulate 36 different cases to compare with simultaneous experiment designed to measured strain within same period. The second investigation involved instrumenting a full-scale PV solar panel specimen with 13 half-bridge strain gauges on both surfaces of the PV solar panel, which were used to measure strain values in longitudinal and transversal directions of solar panel and also on the top and bottom edges of the same panel. According to an equivalent uniform Young’s modulus numerically determined for the five layers of the PV solar panel, and with respect to the Hook’s law, the stresses were found to be equal to 50 Mpa for strain gauges at the mid area of PV solar panel,. This value was used to calibrate boundary conditions of the FE model namely the Fix-Equal and the Pin-Equal conditions along the edges of the solar panel and along the mounting frame.

L’augmentation de la population mondiale et l’urbanisation croissante conduisent à une densification urbaine qui menace l’accès des habitants des villes au soleil et à la lumière naturelle. Cet accès est lié à des problématiques de consommation d’énergie, de santé et de bien-être ; il peut être limité par plusieurs caractéristiques du tissu urbain telles que la largeur des rues, la hauteur des bâtiments, la clarté des façades et de la chaussée. Nous avons étudié l’influence des caractéristiques les plus importantes d’un canyon urbain sur la disponibilité de la lumière naturelle à l’intérieur du canyon sous des conditions climatiques réelles. Nous avons fabriqué dans ce but, le modèle réduit d’un canyon urbain, la représentation simplifiée d’une rue. Cette maquette est modifiable, le rapport d’aspect H/W (Hauteur/Largeur) du canyon peut être modifié et les façades sont interchangeables. Durant une année, les éclairements lumineux y ont été mesurés sur le sol et à plusieurs hauteurs des façades, au pas de la minute, sous des conditions de ciel réelles. Au total, 12 configurations sont représentées dans la base de données obtenue, avec 3 rapports d’aspect : H/W=0,5, 1 et 2, et 4 types de façades de facteur de réflexion lumineux différent. Les revêtements de façade utilisés sont : noir, blanc, crépi et crépi avec des parties vitrées. Nous étudions l’influence de ces paramètres en fonction des types de ciel définis par la CIE pour un canyon orienté nord/sud. Nous utilisons aussi ces données pour étudier l’usage, la performance et la précision de trois logiciels de modélisation du rayonnement solaire en milieu urbain : Citysim, Daysim et Heliodon. Ces trois logiciels offrant différents niveaux de simplification. Enfin, nous avons mené une campagne de mesure dans les rues de Lyon. Cela nous a permis de nous confronter à la réalité des données de terrain, juger des difficultés à les recueillir et à modéliser le rayonnement solaire dans l'espace réel. Nous avons aussi évalué une nouvelle méthode de mesure des éclairements lumineux d’une façade. Cette méthode se base sur des cartes de luminances obtenues à partir de photos fisheye avec un appareil photo numérique étalonné en luminances. La comparaison de ces mesures avec celles de la maquette permet d’évaluer l’erreur commise en utilisant un revêtement simplifié. En utilisant les données récoltées sur la maquette, le rapport d’aspect H/W=1 permet d’obtenir le meilleur accès à la lumière naturelle dans le canyon, il correspond à un bon compromis entre la contribution des façades et du ciel. Pour chaque ville, une configuration optimale peut être déterminée en fonction du climat local, qui peut être représenté par la fréquence d’observation des différents types de ciel CIE. Nous avons évalué la capacité des logiciels choisis à prendre en compte le climat. Avec Heliodon, il est possible d’obtenir des éclairements lumineux proches de ceux mesurés sur la maquette, pour des ciels sans nuages. Puisque le climat varie tout au long de l’année, la prise en compte des 15 types de ciel CIE doit être préférée à l’utilisation d’un ciel uniquement sans nuages, ou couvert comme cela est souvent le cas. Les logiciels Citysim et Daysim sont capables de prendre en compte le climat réel et produisent de bonnes corrélations avec les mesures effectuées sur la maquette pour tous les types de ciel. / As the world population and the urbanization increase, cities become denser, thus reducing access to daylight and sunlight for city dwellers. This access is linked to some issues such as energy consumption, health and comfort; it can be limited by several urban fabric features such as street width, building height, façade and road coating. We have evaluated the influence of the most important features of an urban canyon regarding daylight availability inside the canyon under real sky conditions.To that end, we have built a scale model of an urban canyon, the simplest representation of a street. This scale model can be modified: the aspect ratio H/W (Height/Width) can be changed as well as the type of façade. During one year, outdoor illuminances have been measured every minute on the ground and at different heights of the façades. Hence, we created a database containing twelve combinations of an urban canyon with the following parameters: three aspect ratios (H/W=2, 1 and 0.5) and four types of façades with different reflection factors. The different coatings of the façades are: black, white, roughcast and roughcast with windows. We evaluate the influence of these parameters for each type of sky defined according to the CIE for a north/south orientated canyon.We also use this database in order to evaluate the ease of use, performance and precision of three software tools for the estimation of solar radiation in urban context: Citysim, Daysim and Heliodon, each having different simplification levels.Finally, we have carried a measuring campaign in the streets of the French city of Lyons. This campaign allowed us to realize the difficulty of collecting data in the field and modelling solar radiation of a real street. We have also assessed a new method for measuring illuminances of a whole façade. This method is based on a luminance map generated from a calibrated digital camera equipped with a fisheye lens. A comparison between these illuminances with illuminances measured on the scale model with regular sensors allows us to estimate the bias of using a simplified coating.Based on illuminances measured on the scale model, a canyon with an aspect ratio H/W=1 has a better access to daylight, it represents a good compromise between contributions of the sky and the opposing façade. Every city has an optimal canyon shape according to its local climate that could be defined as the frequency of occurrence of the CIE types of sky. We have evaluated the ability of the selected software tools to take into account the climate. For clear skies, Heliodon is able to produce illuminances close to those measured on the scale model. Because the weather changes throughout the year, one would rather take into account the 15 CIE types of sky instead of using either a clear sky or an overcast sky as many studies do. Citysim and Daysim are able to take into account the climate and correlate well with scale model measurements for each type of sky. The method for measuring illuminances using a fisheye lens camera has been validated based on the measurements in real streets of Lyons. This method could produce more accurate values using a reflection factor map of the façade. Illuminances measured on the scale models didn’t correlate well with illuminances measured in real streets because of the complexity of the streets compared to the simplicity of the idealized canyon of the scale model. The use of simplified models of streets can lead to bad results, for instance, with studies estimating the energy consumption of buildings for lighting at district or urban scale. The density of urban areas must decrease in order to improve access to daylight. That would provide other advantages such as the reduction of exposure to vehicles pollution or reduction of the urban heat island. The calculation of an ideal aspect ratio could be achieved using tools evaluated in this thesis.

Envelopes with low thermal performance are common characteristics in European historic buildings resulting in insufficient thermal comfort and higher energy use compared to modern buildings. There are different types of applications for the European historic buildings such as historic churches, historic museums, historic theatres, etc. In historic buildings refurbished to offices, it is vital to improve thermal comfort for the staff. Improving thermal comfort should not increase, preferably reduce, energy use in the building. The overall aim in this research is to explore how to improve thermal comfort in historic buildings without increasing, preferably reducing, energy use with the application of non-intrusive methods. This is done in form of a case study in Sweden. Thermal comfort issues in the case study building are determined through a field study. The methods include field measurements with thermal comfort equipment, data logging on BMS, and evaluating the occupant’s perception of a summer and a winter period indoor environment using a standardized questionnaire. According to questionnaire and thermal comfort measurements results, it is revealed that the summer period has the most dissatisfied occupants, while winter thermal comfort is satisfactory – but not exceptionally good. Accordingly, natural heat sinks could be used in form of NV, as a non/intrusive method, in order to improve thermal comfort in the building. For the historic building equipped with mechanical ventilation, NV strategy has the potential to both improve thermal comfort and reduce the total electricity use for cooling (i.e. electricity use in the cooling machine + the electricity use in the ventilation unit’s fans). It could decrease the percentage of exceedance hours in offices by up to 33% and reduce the total electricity use for cooling by up to 40%. The optimal (maximum) NV rate (i.e. the potential of NV strategy) is dependent on the thermal mass capacity of the building, the available NV cooling potential (dependent on the ambient air temperature), COP value of the cooling machine, the SFP model of the fans (low SFP value for high NV rate is optimal), and the offices’ door scheme (open or closed doors).