977 resultados para Solar panels
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The growing demand for electrical power and the limited capital invested to provide this power is forcing countries like Brazil to search for new alternatives for electrical power generation. The purpose of this paper is to present a technical and economic study on a 15 kW solar plant installed in an isolated community, highlighting the importance of the need for financial subsidy from the government. It evaluates the importance of parameters such as the annual interest rate, specific investment, the marginal cost of expanding the electrical power supply and the government subsidy on amortization time of capital invested. © 2012 Elsevier Ltd All rights reserved.
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This paper is about a case study of using solar energy and wind energy in a farm. For this purpose were collected from the property, such as water consumption and amount of residents. So, we estimate how many conventional panels or PET bottle panels and boiler needed to supply the farm with warm water. It also calculates the amount of photovoltaic panels and the main accessories for converting solar energy into electrical energy. For the pumping of water using photovoltaic panels is dismissed and dimensioned to be a watermill
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Pós-graduação em Engenharia Mecânica - FEG
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Commercial aluminium foam filled structures and sandwich panels are available for structural applications. As alternative to these materials, small granular foamed pieces are proposed to fill structures as well as sandwich panels. On the present work, foam precursors are obtained by Powder Metallurgy (PM) route, using natural calcium carbonate as foaming agent instead of titanium hydride. Extruded precursor bars were cut into small pieces (around 4.5 mm long and 5mm in diameter). Foaming treatment was carried out on two different ways: electrical preheated furnace and by solar furnace. Foamed nodules presented a low cell size, density e.g. 0.67 g/cm3 to 0.88 g/cm3 and a height/diameter ratio between 0.72 and 0.84 as a function of precursor size. These properties depend on the foaming particle size, foaming cycle and precursor dimensions. Carbonate precursors are easily foamed by concentrated solar energy, due to the lower risk of cell collapse than with hydride precursors, resulting from cell stabilization by oxide skin formation into cells and a low degree of foamed nodules bonding.
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Esta Tesis plantea la pregunta de si el uso de morteros con parafinas microencapsuladas combinado con colectores solares térmicos puede reducir el consumo de energías convencionales, en un sistema tradicional de suelo radiante. Se pretende contribuir al conocimiento acerca del efecto que produce en el edificio, el calor latente acumulado en suelos radiantes, utilizando morteros de cemento Portland con material de cambio de fase (PCM), en conjunto con la energía solar. Para cumplir con este propósito, la investigación se desarrolla considerando diversos aspectos. En primer lugar, se revisa y analiza la documentación disponible en la actualidad, de almacenamiento de energía mediante calor latente en la construcción, y en particular la aplicación de microcápsulas de PCM en morteros y suelos radiantes. También se revisa la documentación relacionada con la aplicación de la energía solar térmica y en suelo radiante. Se analiza la normativa vigente respecto al material, a los colectores solares y al suelo radiante. Se verifica que no hay normativa relacionada con mortero-PCM, debido a esto se aplica en la investigación una adaptación de la existente. La fase experimental desarrollada esta principalmente dirigida a la cuantificación, caracterización y evaluación de las propiedades físicas, mecánicas y térmicas del mortero de cemento Portland con parafinas microencapsuladas. Los resultados obtenidos y su análisis, permiten conocer el comportamiento de este tipo de morteros, con las diferentes variables aplicadas en la investigación. Además, permite disponer de la información necesaria, para crear una metodología para el diseño de morteros con parafina microencapsulada, tanto del punto de vista de su resistencia a la compresión y contenido de PCM, como de su comportamiento térmico como acumulador de calor. Esto se logra procesando la información obtenida y generando modelos matemáticos, para dosificar mezclas, y predecir la acumulación de calor en función de su composición. Se determinan los tipos y cantidades de PCM, y el cemento más adecuado. Se obtienen importantes conclusiones respecto a los aspectos constructivos a considerar en la aplicación de morteros con PCM, en suelo radiante. Se analiza y evalúa la demanda térmica que se puede cubrir con el suelo radiante, utilizando morteros con parafina microencapsulada, a través de la acumulación de energía solar producida por colectores solares, para condiciones climáticas, técnicas y tipologías constructivas específicas. Se determina que cuando los paneles cubren más de 60 % de la demanda por calefacción, se puede almacenar en los morteros con PCM, el excedente generado durante el día. Se puede cubrir la demanda de acumulación de energía con los morteros con PCM, en la mayoría de los casos analizados. Con esto, se determina que el uso de morteros con PCM, aporta a la eficiencia energética de los edificios, disminuyendo el consumo de energías convencionales, reemplazándola por energía solar térmica. En esta investigación, el énfasis está en las propiedades del material mortero de cemento-PCM y en poder generar metodologías que faciliten su uso. Se aborda el uso de la energía solar, para verificar que es posible su acumulación en morteros con PCM aplicados en suelo radiante, posibilitando el reemplazo de energías convencionales. Quedan algunos aspectos de la aplicación de energía solar a suelo radiante con morteros con PCM, que no han sido tratados con la profundidad que requieren, y que resultan interesantes de evaluar en este tipo de aplicaciones constructivas, como entre otros, los relacionados con la cuantificación de los ahorros de energía en las diferentes estaciones del año, de la estabilización de temperaturas internas, su análisis de costo y la optimización de este tipo de sistemas para utilización en verano, los que dan pie para otras Tesis o proyectos de investigación. ABSTRACT This Thesis proposes the question of whether the use of mortars with microencapsulated paraffin combined with solar thermal collectors can reduce conventional energy consumption in a traditional heating floor system. It aims to contribute to knowledge about the effect that it has on the building, the latent heat accumulated in heating floor, using Portland cement mortars with phase change material (PCM), in conjunction with solar energy. To fulfill this purpose, the research develops it considering various aspects. First, it reviews and analyzes the documentation available today, about energy storage by latent heat in the building, and in particular the application of PCM microcapsules in mortars and heating floors. It also reviews the documentation related to the application of solar thermal energy and heating floor. Additionally, it analyzes the current regulations regarding to material, solar collectors and heating floors. It verifies that there aren’t regulations related to PCM mortar, due to this, it applies an adaptation in the investigation. The experimental phase is aimed to the quantification, mainly, characterization and evaluation of physical, mechanical and thermal properties of Portland cement mortar with microencapsulated paraffin. The results and analysis, which allow us to know the behavior of this type of mortars with different variables applied in research. It also allows having the information necessary to create a methodology for designing mortars with microencapsulated paraffin, both from the standpoint of its resistance to compression and PCM content, and its thermal performance as a heat accumulator. This accomplishes by processing the information obtained, and generating mathematical models for dosing mixtures, and predicting heat accumulation depending on their composition. The research determines the kinds and amounts of PCM, and the most suitable cement. Relevant conclusions obtain it regarding constructive aspects to consider in the implementation of PCM mortars in heating floor. Also, it analyzes and evaluates the thermal demand that it can be covered in heating floor using microencapsulated paraffin mortars, through the accumulation of solar energy produced by solar collectors to weather conditions, technical and specific building typologies. It determines that if the panels cover more than 60% of the demand for heating, the surplus generated during the day can be stored in PCM mortars. It meets the demand of energy storage with PCM mortars, in most of the cases analyzed. With this, it determines that the use of PCM mortars contributes to building energy efficiency, reducing consumption of conventional energy, replacing it with solar thermal energy. In this research approaches the use of solar energy to determine that it’s possible to verify its accumulation in PCM mortars applied in heating floor, enabling the replacement of conventional energy. The emphasis is on material properties of PCM mortar and, in order to generate methodologies to facilitate their use. There are some aspects of solar energy application in PCM mortars in heating floor, which have not been discussed with the depth required, and that they are relevant to evaluate in this kind of construction applications, including among others: the applications related to the energy savings quantification in different seasons of the year, the stabilizing internal temperatures, its cost analysis and optimization of these systems for use in summer, which can give ideas for other thesis or research projects.
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During launch, satellite and their equipment are subjected to loads of random nature and with a wide frequency range. Their vibro-acoustic response is an important issue to be analysed, for example for folded solar arrays and antennas. The main issue at low modal density is the modelling combinations engaging air layers, structures and external fluid. Depending on the modal density different methodologies, as FEM, BEM and SEA should be considered. This work focuses on the analysis of different combinations of the methodologies previously stated used in order to characterise the vibro-acoustic response of two rectangular sandwich structure panels isolated and engaging an air layer between them under a diffuse acoustic field. Focusing on the modelling of air layers, different models are proposed. To illustrate the phenomenology described and studied, experimental results from an acoustic test on an ARA-MKIII solar array in folded configuration are presented along with numerical results.
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Due to the high dependence of photovoltaic energy efficiency on environmental conditions (temperature, irradiation...), it is quite important to perform some analysis focusing on the characteristics of photovoltaic devices in order to optimize energy production, even for small-scale users. The use of equivalent circuits is the preferred option to analyze solar cells/panels performance. However, the aforementioned small-scale users rarely have the equipment or expertise to perform large testing/calculation campaigns, the only information available for them being the manufacturer datasheet. The solution to this problem is the development of new and simple methods to define equivalent circuits able to reproduce the behavior of the panel for any working condition, from a very small amount of information. In the present work a direct and completely explicit method to extract solar cell parameters from the manufacturer datasheet is presented and tested. This method is based on analytical formulation which includes the use of the Lambert W-function to turn the series resistor equation explicit. The presented method is used to analyze commercial solar panel performance (i.e., the current-voltage–I-V–curve) at different levels of irradiation and temperature. The analysis performed is based only on the information included in the manufacturer’s datasheet.
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Due to the high dependence of photovoltaic energy efficiency on environmental conditions (temperature, irradiation...), it is quite important to perform some analysis focusing on the characteristics of photovoltaic devices in order to optimize energy production, even for small-scale users. The use of equivalent circuits is the preferred option to analyze solar cells/panels performance. However, the aforementioned small-scale users rarely have the equipment or expertise to perform large testing/calculation campaigns, the only information available for them being the manufacturer datasheet. The solution to this problem is the development of new and simple methods to define equivalent circuits able to reproduce the behavior of the panel for any working condition, from a very small amount of information. In the present work a direct and completely explicit method to extract solar cell parameters from the manufacturer datasheet is presented and tested. This method is based on analytical formulation which includes the use of the Lambert W-function to turn the series resistor equation explicit. The presented method is used to analyze the performance (i.e., the I - V curve) of a commercial solar panel at different levels of irradiation and temperature. The analysis performed is based only on the information included in the manufacturer's datasheet.
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Anew, simple, and quick-calculationmethodology to obtain a solar panel model, based on the manufacturers’ datasheet, to perform MPPT simulations, is described. The method takes into account variations on the ambient conditions (sun irradiation and solar cells temperature) and allows fast MPPT methods comparison or their performance prediction when applied to a particular solar panel. The feasibility of the described methodology is checked with four different MPPT methods applied to a commercial solar panel, within a day, and under realistic ambient conditions.
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Este trabajo se ocupa de la construcción modular ligera de viviendas unifamiliares, más concretamente aborda el problema de la definición constructiva de las mismas, habida cuenta de lo poco conocido y publicado de este aspecto en particular. Dado que la construcción es fruto de la evolución, resulta de gran importancia el estudio de los antecedentes para comprender la situación actual, por ello para documentar como corresponde el estado de la técnica y de la investigación se estudiaron los antecedentes desde sus primeras manifestaciones a finales del siglo XIX hasta nuestros días. Contrariamente a las profecías de Le Corbusier y otros, la industrialización no ha llegado a la construcción ni en la forma ni en la medida que era de esperar a principios del siglo XX. Sin embargo y a pesar del relativo “fracaso” de la industrialización en convertirse en la forma mayoritaria de producir edificios, lo cierto es que algunos sistemas altamente industrializados, como lo es la construcción modular ligera, han logrado un lugar en el mercado, que en algunos países resulta cuanto menos significativo. Delimitar el estado de la técnica y la situación actual es crucial en este trabajo, toda vez que la construcción industrializada la realizan empresas, y situarse al margen de las mismas y de su producción, nos guste o no, resulta contrario al sentido común. De este modo se han identificado y documentado ejemplos como el de EE.UU. y Japón, entre otros, que resultan muy ilustrativos tanto desde la evolución como del estado actual. Del estado de la técnica y la investigación también resulta la escasez de publicación de detalles constructivos específicos de la construcción modular ligera. Es obvio que los fabricantes intentan blindarse mediante el secreto industrial, logrando que las soluciones constructivas más interesantes queden fuertemente protegidas dentro del conocimiento reservado de la empresa. De este modo un sistema que alcanza grados de prefabricación del 95%, tan atractivo e interesante para el arquitecto queda reservado al conocimiento de unos pocos dentro de las empresas. La búsqueda de mayor información sobre estos sistemas encuentra un filón indiscutible en los proyectos de las casas del concurso Solar Decathlon. En efecto, debido a las condiciones particulares de este concurso, las casas que compiten deben ser instaladas en un plazo corto, por lo que en su mayoría recurren al método de construcción modular ligera, para lograr correctamente este objetivo. Adicionalmente todos los planos de proyecto incluidos los de detalle, así como memorias de especificaciones técnicas, quedan colgadas en la Web, a libre disposición del público. De este modo se ha considerado interesante, conveniente y útil, aprovechar como fuente documental de este trabajo, aparte de lo obtenido en el estado de la técnica y la investigación, los proyectos de las casas de los concursos 2005 y 2007, que fueron las dos últimas ediciones celebradas cuando se inició esta tesis. De modo similar a esta carencia de detalles publicados se observa igualmente una falta de investigación y de metodologías adecuadas a la misma sobre soluciones y detalles constructivos propios de la construcción modular ligera. Por eso y ante la dificultad de manejar adecuadamente una información disponible pero farragosa, este trabajo ha dedicado una parte importante de su esfuerzo a la creación de una metodología adecuada a este tipo de situación. Hay que destacar que cada proyecto puede constar fácilmente de 60 a casi 200 planos, sin contar las memorias técnicas y otros documentos, tales como galerías de imágenes, etc. Por otra parte resulta útil establecer esta metodología, no solo para esta tesis, sino para futuros trabajos de investigación sobre el tema, toda vez que con posterioridad a 2007 se han celebrado nuevas ediciones del concurso con su correspondiente volumen de información disponible. La metodología del análisis de los proyectos se basa en el diseño y creación de siete fichas tipo que resumen los aspectos fundamentales del proyecto desde el punto de vista constructivo, permitiendo de este modo su rápida visualización y comprensión sin pretender exhaustividad, ya que en caso de querer profundizar en el detalle de la información siempre está el proyecto original para ello. Tras estudiar la información obtenida de los proyectos de las casas de concurso, se contrastan y discuten los resultados para obtener conocimientos de interés para el objetivo propuesto en la tesis. Se comparan los resultados procedentes del estado de la técnica y de la investigación y se obtienen las conclusiones correspondientes. De este modo ha sido posible identificar una serie de criterios técnicos de proyecto de viviendas unifamiliares realizadas mediante construcción modular ligera, que además se organizan en varios niveles, por lo que el resultado es un conjunto de criterios como germen de una futura guía o manual. Como conclusiones fundamentales de la tesis hay que destacar las metodológicas, que habilitan la extensión de este estudio a otros trabajos y la aportación original al conocimiento con la definición de una serie de criterios técnicos de proyecto de viviendas realizadas mediante construcción modular ligera, que además de mejorar esta parte del saber constructivo serán de gran ayuda a los arquitectos de cara a la reducción de errores, que a menudo derivan en mayores costes y plazos, cuando no directamente al abandono del sistema constructivo. El trabajo de la tesis se estructura en siete capítulos a saber: Capítulo 1: Introducción, donde se explica el tema de la tesis, el objetivo principal, las limitaciones y se aportan algunas definiciones. Capítulo 2: Estado de la técnica y la investigación, dentro del cual se presentan los antecedentes desde sus inicios pasando por la primera y segunda mitad del siglo XX y finalizando con el estado actual que recorre los sistemas de EE.UU, Japón, Europa, Escandinavia, centro Europa, Francia, España y algunos ejemplos de Latinoamérica. En el estado de la investigación se presentan las publicaciones tanto en revistas científicas indexadas en el JCR, como publicaciones no indexadas en las que se muestran artículos científicos, comunicaciones a congresos, documentación sobre el concurso Solar Decathlon, libros específicos y libros genéricos sobre construcción modular ligera, tesis doctorales tanto generales como específicas sobre el concurso Solar Decathlon, documentos de idoneidad técnica, páginas Web del concurso Solar Decathlon y finalmente páginas Web de empresas de construcción modular ligera y patentes. También se expresan las conclusiones parciales del capítulo así también como la justificación y los objetivos particulares. Capítulo 3: Metodología, se expone en primer lugar el planteamiento del problema, para luego desarrollar los métodos utilizados para el estudio y clasificación del transporte y de la organización modular, la relación entre la organización modular y distribución espacial, el diseño y contenido de las fichas resumen de los 38 proyectos presentados al SD2005 y SD2007, así también como la información consultada para su realización. Se explica asimismo como se realizaron las tablas comparativas partiendo de la información de las fichas. Finalmente se expresa la manera en que se trató el estudio particular de la junta entre módulos. Capítulo 4: Discusión de resultados, dónde en primer lugar se presenta la clasificación y las estrategias del transporte así también como una clasificación de la organización modular, en segundo lugar se estudian las relaciones que existen entre el sistema modular y la organización espacial. A partir de aquí se muestra el estudio de la estructura de todas las casas del SD2005 y SD2007, según el tipo y material de las zapatas, mostrando tanto tablas cuantitativas como tablas gráficas con fotos. De la misma manera se tratan los forjados, los pilares y las vigas y las cubiertas. Se estudia además el cerramiento opaco y acristalado, la cubierta y el forjado según las capas que lo componen. En el caso de las instalaciones se estudian las que son especiales, descartando las normales en este tipo de casas, como son los paneles fotovoltaicos, placas térmicas o tubos de vacío y los sistemas de almacenamiento de energía, como las baterías, presentando tablas numéricas y gráficas con fotos. El transporte se analiza según corresponda al traslado de la vivienda o al transporte de apoyo, según el tipo y la cantidad utilizado. Con respecto al montaje se diferencia en si se usó grúa o no, y en el caso de no utilizarse se muestran los métodos alternativos. Con respecto a la exploración de la organización modular se presentan la cantidad de módulos que utilizó cada casa, así como también la cuantificación de los sistemas híbridos como son elementos lineales 1D, paneles 2D. Por último se muestra el estudio detallado de la junta entre módulos 3D. Finalmente se realiza la propuesta de un conjunto de criterios técnicos de proyecto organizado en cuatro niveles: 1º nivel de criterios generales, 2º nivel sobre sistemas constructivos, 3º nivel de detalles constructivos y el 4º nivel llamado logística obras previas, transporte y montaje. Capítulo 5: Conclusiones y líneas futuras de investigación, se exponen las conclusiones generales, metodológicas, documentales y por último las de construcción modular. Finalmente se realiza una propuesta de líneas futuras de investigación. Capítulo 6: Bibliografía. Capítulo 7: Anexos, en el que se presentan todas las fichas resumen de las casas realizadas por el autor de esta tesis. Además se incluyen los casos concretos de Voisin en Francia y la TVA (Tennessee Valley Authority) en EE.UU., así como referencias de manuales genéricos de construcción ligera, medidas de transporte en España e información sobre estadísticas de viviendas en la Unión Europea. ABSTRACT This paper deals with Light Modular Construction of houses, and specifically addresses the problem of the constructive definition of the same, given how little known and published this subject has been. Since building construction is the result of evolution, it is of great importance to study its background for understanding the current situation, therefore to document the state of the art and research, its history was studied from its origins dating to the end nineteenth century to our days. Contrary to the prophecies of Le Corbusier and others, industrialization has not reached the construction neither in the form nor to the extent that it was expected in the early twentieth century. However, despite the relative "failure" of industrialization to become the major form of production for buildings, the fact is that some highly industrialized systems, such as the so called Lightweight Modular Construction, have achieved a place in the market, which in some countries is at least significant. To outline the state of the art and the current situation is crucial in this work, since industrialized construction is carried out by companies, and to step away from them and their production, whether we like it or not, it is contrary to common sense. So that, several cases have been identified and documented, such as the US and Japan examples, among others, which are very illustrative both from evolution and the current status. The state of the art and research shows also a shortage of publication of specific construction details of light modular construction. Obviously, manufacturers try to shield themselves by trade secret, making the most interesting constructive solutions remain heavily protected within the reserved knowledge of the company, so a system that reaches levels of 95% prefabrication, so attractive and interesting for the architect It is reserved to the knowledge of a few people inside the companies. The search for more information on these systems finds an invaluable reef in the projects of the Solar Decathlon houses. Indeed, due to the particular conditions of this contest, houses competing must be installed in a short time, so mostly turn to modular construction methods for this purpose to achieve properly this goal. Additionally all levels of project, including detailed and technical specifications reports are published on the Web, freely available to the general public. Thus it was considered interesting, convenient and useful to take advantage as a documentary source of this work, apart from what it were obtained in the state of the art and research, the projects of the houses of the 2005 and 2007 contests, which were the last two editions already held before this thesis was started. Similar to this lack of published details it is also observed a lack of research and methodologies adapted to the solutions and construction details of lightweight modular construction. So that, and facing the difficulty of adequately manage the available but bulky information, this work has devoted a significant part of its effort to create an appropriate methodology for this type of situation. It is noteworthy that each project can easily consist of 60 to almost 200 blueprints, not including technical reports and other documents, such as photo galleries, etc. The methodology of the analysis of the projects is based on the design and creation of seven record sheets that summarize key aspects of the project from a construction point of view, thus allowing quick watching and understanding of the project, without claiming completeness, always keeping for further information the blueprints themselves. After studying the information obtained from the projects of the competition houses, the results are compared and discussed to obtain relevant knowledge according to the objective proposed in the thesis. The results from the state of the art and research are also compared and the conclusions so obtained make possible to identify a number of technical design criteria for single family homes made using lightweight modular construction, which also have been organized at various levels, so the result is a set of criteria as a seed for a future guide or manual. Among the main conclusions of the thesis must be noted the methodological ones, that enable the extension of this study to other works and are an original contribution to knowledge with the definition of a number of technical criteria for housing projects made by light modular construction, what in addition to improving this part of the constructive knowledge will be of great help for the architects to reduce errors that often result in higher costs and delays, if not in abandonment of the construction system itself. The work of the thesis is divided into seven chapters as follows: Chapter 1: Introduction, where the topic of the thesis, the main objective, limitations and the provided definitions is explained. Chapter 2: State of the art and research, within which history is presented from the beginning through the first and second half of the twentieth century and ending with the current systems, that spans from the USA to Japan, Europe, Scandinavia, Central Europe, France, Spain and some Latin American examples. In the state of research publications are presented both on scientific journals indexed in the JCR, and non-indexed publications in which scientific articles, conference papers, information about the Solar Decathlon competition, generic and specific books on light modular construction, articles both general and specific on the Solar Decathlon competition, technical approval documents, dissertations, the Solar Decathlon Web pages and finally lightweight modular construction companies Web pages and patents. The partial conclusions of the chapter as well as the rationale and specific objectives are also expressed. Chapter 3: Methodology first of all exposes the problem statement and then develops the methods used for the study and classification of transportation and modular organization, the relationship between the modular organization and spatial distribution, design and content summary records of the 38 projects submitted to the SD2005 and SD2007, as well as information consulted for its realization. It explains equally how the comparative tables based on information from the chips were made. Finally, the way the particular study of the joint between modules is carried out is also treated. Chapter 4: Discussion, first sorting a classification of transport strategies as well as of modular organization, secondly the relationship between the modular system and the spatial organization studied is presented. From then on, the study of the structure of every house Moreover, to establish this methodology is useful not only for this thesis, but for future research on the subject, since after 2007 there have been held new editions of the contest with a corresponding volume of information available. shown in the SD2005 and SD2007 contests, depending on the type and material of the shoe, showing both quantitative tables as graphic boards with pictures is carried out. Similarly slabs, columns and beams and roofs are treated. Furthermore, the opaque and transparent façades, as well as roof and floor enclosure, according to the layers that compose them are studied. In the case of facilities there have been only addressed that which are of a special type, discarding that considered usual in this type of houses such as photovoltaic panels, thermal panels or vacuum tubes and energy storage systems such as batteries, presenting numerical and graphical tables with photos .The transportation is analyzed depending on it is used to move the house or for additional support, depending on the type and quantity of items used. Regarding assembly it has been made a difference if crane is or not used and if not, what the alternative methods are. With respect to the exploration of the modular organization, the amount of modules used in each house is presented, as well as the quantification of hybrid systems such as linear members as well as 1D, 2D panels. Finally, it has been carried out the detailed study of the joint between 3D modules. Finally it is proposed a set of technical criteria organized into four levels, 1st level of general criteria, 2nd level on building systems, 3rd level construction details and 4th level called previous works and logistics, transportation and assembly. Chapter 5: Conclusions and future research, where general, methodological, documentary and finally modular construction findings are presented. A proposal for further research is done. Chapter 6: Bibliography. Chapter 7: Annexes, in which all the record sheets of houses made by the author of this thesis are presented. Besides the specific cases of Voisin in France and TVA (Tennessee Valley Authority) in the USA, as well as general reference manuals on lightweight construction, transportation dimensions in Spain, and information on housing statistics in the European Union are included.
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Solar heating of potable water has traditionally been accomplished through the use of solar thermal (ST) collectors. With the recent increases in availability and lower cost of photovoltaic (PV) panels, the potential of coupling PV solar arrays to electrically heated domestic hot water (DHW) tanks has been considered. Additionally, innovations in the SDHW industry have led to the creation of photovoltaic/thermal (PV/T) collectors, which heat water using both electrical and thermal energy. The current work compared the performance and cost-effectiveness of a traditional solar thermal (ST) DHW system to PV-solar-electric DHW systems and a PV/T DHW system. To accomplish this, a detailed TRNSYS model of the solar hot water systems was created and annual simulations were performed for 250 L/day and 325 L/day loads in Toronto, Vancouver, Montreal, Halifax, and Calgary. It was shown that when considering thermal performance, PV-DHW systems were not competitive when compared to ST-DHW and PVT-DHW systems. As an example, for Toronto the simulated annual solar fractions of PV-DHW systems were approximately 30%, while the ST-DHW and PVT-DHW systems achieved 65% and 71% respectively. With current manufacturing and system costs, the PV-DHW system was the most cost-effective system for domestic purposes. The capital cost of the PV-DHW systems were approximately $1,923-$2,178 depending on the system configuration, and the ST-DHW and PVT system were estimated to have a capital cost of $2,288 and $2,373 respectively. Although the capital cost of the PVT-DHW system was higher than the other systems, a Present Worth analysis for a 20-year period showed that for a 250 L/day load in Toronto the Present Worth of the PV/T system was approximately $4,597, with PV-DHW systems costing approximately $7,683-$7,816 and the ST-DHW system costing $5,238.
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Electric vehicles (EVs) provide a feasible solution to reducing greenhouse gas emissions and thus become a hot topic for research and development. Switched reluctance motors (SRMs) are one of promised motors for EV applications. In order to extend the EVs’ driving miles, the use of photovoltaic (PV) panels on the vehicle helps decrease the reliance on vehicle batteries. Based on phase winding characteristics of SRMs, a tri-port converter is proposed in this paper to control the energy flow between the PV panel, battery and SRM. Six operating modes are presented, four of which are developed for driving and two for standstill on-board charging. In the driving modes, the energy decoupling control for maximum power point tracking (MPPT) of the PV panel and speed control of the SRM are realized. In the standstill charging modes, a grid-connected charging topology is developed without a need for external hardware. When the PV panel directly charges the battery, a multi-section charging control strategy is used to optimize energy utilization. Simulation results based on Matlab/Simulink and experiments prove the effectiveness of the proposed tri-port converter, which has potential economic implications to improve the market acceptance of EVs.
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At the present there is a high pressure toward the improvement of all production processes. Those improvements can target distinct factors along the production chain. In particular, and due to recent tight energy efficiency policies, those that involve energy efficiency. As can be expected, agricultural processes are not immune to this tendency. Even more when dealing with indoor productions. In this context, this work presents an innovative system that aims to improve the energy efficiency of a trees growing platform. This improvement in energy consumption is accomplished by replacing an electric heating system by one based on thermodynamic panels. The assessment of the heating fluid caudal and its temperature was experimentally obtained by means of a custom made scaled prototype whose actuators status are commanded by a Fuzzy-based controller. The obtained results suggest that the change in the heating paradigm will lead to overall savings that can easily reach 60% on the energy bill.
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Nowadays, the development of the photovoltaic (PV) technology is consolidated as a source of renewable energy. The research in the topic of maximum improvement on the energy efficiency of the PV plants is today a major challenge. The main requirement for this purpose is to know the performance of each of the PV modules that integrate the PV field in real time. In this respect, a PLC communications based Smart Monitoring and Communications Module, which is able to monitor at PV level their operating parameters, has been developed at the University of Malaga. With this device you can check if any of the panels is suffering any type of overriding performance, due to a malfunction or partial shadowing of its surface. Since these fluctuations in electricity production from a single panel affect the overall sum of all panels that conform a string, it is necessary to isolate the problem and modify the routes of energy through alternative paths in case of PV panels array configuration.