<p>Though mandatory to be pursued, improved energy efficiency is not the only target to reach. The quality of energy has to be assessed as well. Most of the overall energy use in residential building is for low temperature heat, i.e. temperatures relatively close to the outdoor conditions. From a thermodynamic point of view, this is a degraded form of energy with low potential to be converted into work. On the other hand energy demand is mostly met with high quality energy, such as electricity and natural gas. There is a mismatch between supply and demand, which is not clearly shown by the sole energy analysis. Target of this thesis is to analyze the energy use in buildings from the point of view of its quality, to provide effective theoretical and calculation tools to investigate this mismatch, to assess its magnitudo and to propose improvements aiming at a more rational use of the energy. The idea behind the quality is clarified with the concept of exergy.</p><p>The potential for improvement in space heating is shown. In no heating system the overall exergy efficiency is above 20%, with fossil fuels. Using direct electricity heating results in exergy efficiency below 7%. Most of the household appliances processes have low-exergy factors but still are supplied with electricity. This results in poor exergy efficiencies and large exergy losses.</p><p>Systems are poorly performing because little consideration is explicitly given to energy quality. Policies to lower the energy demand, though vital as first step towards an improved use of energy, should not neglect the exergy content.</p><p>The problem is then shifted to find suitable supplies. Electricity can be exploited with low exergy losses with high-COP heat pumps. Use of fossil fuels for heating purposes should be avoided. District heating from cogeneration and geothermal proves to be a suitable solution at the building level. The issues connected to its exploitation forces to shift the boundary layers of the analysis from the building level to the community level. A rational use of energy should address the community level. The system boundaries have to be enlarged to a dimension where both the energy conversion and use take place with reduced energy transportation losses. This is a cost-effective way to avoid the waste of the exergy potential of the sources with exergy cascade and to make it possible the integration of with renewable sources. Exergy efficiency of the buildings is a prerequisite for a better of energy in this field.</p> / IEA ECBCS Annex 49: Low Exergy Systems for High Performance Buildings and Communities / ESF Cost C24: Analysis and Design of Innovative Systems for Low-EXergy in the Built Environment: COSTeXergy

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Though mandatory to be pursued, improved energy efficiency is not the only target to reach. The quality of energy has to be assessed as well. Most of the overall energy use in residential building is for low temperature heat, i.e. temperatures relatively close to the outdoor conditions. From a thermodynamic point of view, this is a degraded form of energy with low potential to be converted into work. On the other hand energy demand is mostly met with high quality energy, such as electricity and natural gas. There is a mismatch between supply and demand, which is not clearly shown by the sole energy analysis. Target of this thesis is to analyze the energy use in buildings from the point of view of its quality, to provide effective theoretical and calculation tools to investigate this mismatch, to assess its magnitudo and to propose improvements aiming at a more rational use of the energy. The idea behind the quality is clarified with the concept of exergy. The potential for improvement in space heating is shown. In no heating system the overall exergy efficiency is above 20%, with fossil fuels. Using direct electricity heating results in exergy efficiency below 7%. Most of the household appliances processes have low-exergy factors but still are supplied with electricity. This results in poor exergy efficiencies and large exergy losses. Systems are poorly performing because little consideration is explicitly given to energy quality. Policies to lower the energy demand, though vital as first step towards an improved use of energy, should not neglect the exergy content. The problem is then shifted to find suitable supplies. Electricity can be exploited with low exergy losses with high-COP heat pumps. Use of fossil fuels for heating purposes should be avoided. District heating from cogeneration and geothermal proves to be a suitable solution at the building level. The issues connected to its exploitation forces to shift the boundary layers of the analysis from the building level to the community level. A rational use of energy should address the community level. The system boundaries have to be enlarged to a dimension where both the energy conversion and use take place with reduced energy transportation losses. This is a cost-effective way to avoid the waste of the exergy potential of the sources with exergy cascade and to make it possible the integration of with renewable sources. Exergy efficiency of the buildings is a prerequisite for a better of energy in this field. / IEA ECBCS Annex 49: Low Exergy Systems for High Performance Buildings and Communities / ESF Cost C24: Analysis and Design of Innovative Systems for Low-EXergy in the Built Environment: COSTeXergy

To accommodate an expanding global population, a renewable raw material resource base, in conjunction with new building technologies, must be applied to the residential housing sector. Desirable characteristics of housing systems are economy, safety, environmental sustainability, durability, design flexibility and a long service life. The system should be acceptable to the end-user, consist of renewable, indigenous resources, and require a minimum investment in labor and equipment for both production and erection. The objective of this research was to develop a ready-to-assemble (RTA) framing system. Integral to the framing system is a nail plate connector, developed in this project, that laminates wood or wood composite elements into larger building components. The laminated components can be bolted together to form various structural configurations. Decisions on the development of the RTA system were structured according to an Innovation Development Decision Model (IDDP) that was constructed from previous adoption and diffusion research. The IDDP model elucidates and illustrates the innovation process from conceptual idea to product adoption. The critical issues for product acceptance include system performance in terms of safety, cost, and building code approval. The objective of the experimental portion of the research was to test the performance of the RTA connection system in specific modes and to develop a theoretical method to predict the strength of the connection. A series of experiments to quantify the shear strength and stiffness of six joint configurations assembled with the RTA connector were designed and conducted. The joints were fabricated from solid sawn lumber and three different wood-base composites. The experimental results indicated that the strength of the RTA connector in perpendicular-to-grain and parallel-to-grain orientations can be predicted from a theoretical dowel yield model. The material properties used in the yield model were adjusted for duration of load and safety. Empirical test values were within ±6.3 % of the predicted values from the theoretical model. Joint stiffness was evaluated, modeled and quantified in the linear and non-linear ranges. A structural analysis program was used to design and model a simple RTA building for realistic gravity and wind loads. The structural model was used to predict joint forces that the RTA connector must resist in-service. The computer model predictions were compared to the empirical joint test data. The results indicate that the RTA system can be designed to meet safety and serviceability criteria. A comparison between the estimated costs of a RTA building and the costs of traditional on site construction of a building of equal dimensions indicated that the RTA system is economically competitive. / Ph. D.

Door of Return Museum symbolizes a synthesis of environmental building systems (EBS) and extends Senegal's cultural fingerprint along the Atlantic shoreline. Benefits of EBS technologies include ecologic imperatives, coexistence with nature, and transcultural synergies to name a few. Architecturally speaking EBS is the purposeful integration of environmental systems in a harmonious manner that maximizes passive energy solutions to the fullest extent possible. When doing so problems exist both environmental and contextual yet resolutions can be rewarding to the client, community, and most important the end-user. Overcoming problematic challenges maintains sensitivity towards nature, cultural history and vernacular typology. Design methodology mitigates natural systems such as thermal heat transfer, daylight control, natural ventilation and thermal lag prior to incorporating mechanical systems. The paramount result is a contemporary museum that educates via its collection and economized performance systems. / Master of Architecture

The goal of this study was to determine if innovative building methods and materials have the potential to lead to better productivity. Furthermore, this study endeavored to establish the premise that builders who use pre-fabrication, pre-assembly, and modular materials and building methods will perform more productively than those builders who don't. These ideas were pursued by first reviewing the history of home building in the United States to determine trends and patterns in innovation. The experimental phase of the study was accomplished by interviewing local and regional builders about their actual methods of construction used for residential construction. These methods were then analyzed to determine the contribution of these methods to the builder's productivity. Not surprisingly, builders choose one specific type of construction to build a majority of their projects. They use these methods because they are comfortable with them and confident in them; they know they work, and they believe that they are an efficient means of producing a house. It was determined that residential builders in these rural university towns tend to use traditional wood framing construction methods above all of the other available methods. However, there are builders who do use less-conventional methods including: wall panels, pole construction, and modular unit construction. The actual building methods used by builders are somewhat determined by several factors, including: project type, company size and structure, and area of the country. Furthermore, the builders who choose to use non-traditional construction methods with regularity tend to have higher rates of productivity as well as the ability to take on more projects. Higher rates of productivity and the ability to take on more projects have the potential to give builders a competitive advantage over their competition. / Master of Science

Atualmente, os edifícios, em função dos avanços tecnológicos dos sistemas prediais, necessitam de maior planejamento, detalhamento de projetos, controles de execução e treinamento dos profissionais de operação e manutenção para atender os requisitos de projeto do proprietário, que têm como premissa os conceitos de sustentabilidade, qualidade e desempenho. A presença dos sofisticados sistemas de controle contribui para facilitar o gerenciamento de insumos como água e energia, porém pequenas falhas podem levar a grandes falhas de desempenho. As falhas na concepção dos edifícios têm início com a má interpretação, por parte da equipe técnica, dos requisitos dos proprietários. Assim, é necessário que na concepção do edifício sejam verificados todos os requisitos solicitados pelos proprietários para o edifício durante o seu ciclo de vida. A falha da comunicação percorre toda a cadeia produtiva do edifício gerando falhas de planejamento, projeto, execução e manutenção. O comissionamento é um processo para atender aos requisitos de projeto do proprietário, documentar as fases do ciclo de vida dos edifícios, capacitar os profissionais de operação e manutenção, com o objetivo de evitar as falhas, diminuir desperdícios e retrabalhos, melhorar a qualidade, o desempenho e a sustentabilidade dos edifícios. O comissionamento é mais difundido em sistemas prediais de ar condicionado e de iluminação tendo como meta a alta eficiência energética e a economia de água, sendo pouco utilizado no Brasil. Neste contexto, o objetivo desta pesquisa é propor um modelo conceitual de comissionamento para sistemas prediais. A metodologia adotada para o desenvolvimento do modelo, utiliza a pesquisa bibliográfica como procedimento técnico. Para elucidar em que fase o comissionamento é aplicado, este foi relacionado com os outros conceitos utilizados no ciclo de vida do edifício como a coordenação de projeto, o gerenciamento de execução, o gerenciamento de facilidades, a qualidade, o desempenho, a sustentabilidade. Para o desenvolvimento do modelo conceitual é apresentado um fluxo das fases do ciclo de vida e respectivas etapas do comissionamento e outro fluxo com a relação de documentos gerados em cada fase. O resultado, ou seja, o modelo conceitual dá as diretrizes para o desenvolvimento de um comissionamento por meio da descrição das atividades, das competências e dos produtos gerados em cada etapa do comissionamento, conforme as fases do ciclo do edifício. Este trabalho contribui para difundir o comissionamento e embasar a sua aplicação em edifícios. / The buildings of high technology, arising from technological advances in building systems, require more planning, project details, playback controls and training of operating professionals and maintenance to meet the owner\'s project requirements, which is premised on the concept of sustainability, quality and performance. The presence of sophisticated control systems helps to facilitate the management of inputs such as water and energy, however small faults can lead to major performance failures. The flaws in the design of the buildings begin to misinterpretation, by the technical staff, the requirements of the owners. Thus, it is necessary that the design of the building are checked all requirements requested by the building owners to during its life cycle. The failure of the communication runs through the entire production chain of the building generating design flaws, design, execution and maintenance. Commissioning is a process to meet the owner\'s project requirements, document the stages of the life cycle of buildings, train operating professionals and maintenance, in order to avoid failures, reduce waste and rework, improve quality, performance and sustainability of buildings. The commissioning is more widespread in building air conditioning and lighting systems with the goal of high energy efficiency and water savings, being little used in Brazil. In this context, the objective of this research is to propose a conceptual model of commissioning for building systems. The methodology used to develop the model, uses literature as a technical procedure. To elucidate what stage the commissioning is applied, this was related to the other concepts used in the building\'s life cycle, such as: project coordination, execution management, management of facilities, quality, performance, sustainability. To develop the conceptual model presented is a flow of phases of the life cycle and respective process steps and another stream with the list of documents generated at each stage. The result, i.e. the conceptual model gives guidelines for the development of a commissioning through the description of activities, skills and products generated at each stage of the commissioning, according to the phases of building cycle. This work contributes to spread the commissioning and to support its application in buildings.

O presente trabalho consiste em um estudo experimental sobre o efeito do controle de vazões em sistemas de aquecimento solar de água em instalações com grande número de coletores, onde o gradiente de temperatura não é suficiente para circular a água por termossifonagem. Foi avaliado o desempenho de todo o sistema sob diferentes condições de insolação, de vazão, de diferenciais de temperatura entre os coletores e o reservatório, em regime não permanente. Os resultados experimentais foram comparados com a equação de rendimento dos coletores, para condições de regime quase permanente, obtida segundo a norma da ABNT - NBR 10184/1988. Os ensaios foram realizados em duas baterias de testes, cada uma composta de dois coletores industrializados e um reservatório isolado termicamente. Em uma destas baterias, o fluxo de água entre os coletores e o reservatório ocorreu por termossifonagem, isto é, sem nenhuma restrição à vazão; na outra bateria, a vazão foi controlada por um registro e uma bomba hidráulica. Um sistema de automação coletou e processou os dados de forma a permitir a execução dos controles desejados, inclusive a simulação de consumo de água quente. O sistema com circulação natural, isto é, por termossifão, demonstrou ter uma grande habilidade de se adaptar à disponibilidade de energia com as temperaturas da água armazenada, por meio da otimização da velocidade da troca de calor. Foi desenvolvido, tomado como referência o escoamento por termossifão, um modelo de operação para sistemas diretos ativos que calcula a vazão com base no monitoramento das temperaturas das extremidades das tubulações que interligam o reservatório e os coletores, temperatura do ar, radiação solar disponível e vazão no instante anterior. O modelo foi testado experimentalmente e a operação do sistema ativo resultou em significativa melhora a eficiência. / The focus of this work is the experimental study of the effect of water control discharge in solar water-heating systems with a large number of collectors where the temperature gradient is not sufficient for thermosiphon water circulation. The performance of the system was evaluated under different conditions of solar radiation, flow rate, temperature differential between solar collectors and the storage tank and under transient conditions. The results were compared to a collector\'s performance equation of the quasi-steady-state model according to ABNT-NBR 10184/1988 standard. The tests were carried out on two systems each one constituted of two manufacturing collectors and one thermal tank. In one of these systems the flow between the collectors and storage occurred by thermosiphoning, i.e., by natural convection and without discharge restrictions. In the other, the flow control was done by means of a valve and a pump. In order to allow the execution of the desired controls, including hot water consumption, data were colleted and controlled through an automation system. The system of natural circulation shows a great ability to adaptation of disposal energy with water temperature stored, through velocity of heat exchange optimization. An operation model was developed, having thermosiphoning water circulation as reference, for active direct circulation systems that calculate the discharge taking into consideration the monitoring of the differential temperature between solar collectors and the storage tank, the air temperature, solar radiation available and the flow rate on previous time interval. This model was experimentally tested and resulted in a significant improvement in performance of the system operation.

O trabalho enfoca a automação predial, procurando analisar, comparativamente, a utilização de tecnologias convencionais e equipamentos empregados na automação de processos industriais. Através de um estudo de caso, efetuou-se uma descrição dos principais sistemas prediais possíveis de serem automatizados em um edifício, efetuando-se uma avaliação comparativa entre os sistemas convencionais e os baseados na automação de processos, permitindo o uso mais eficiente dos insumos prediais, além de aumentar o conforto e a segurança de seus ocupantes. Verificou-se um grande potencial de aplicação dos sistemas de automação de processos industriais, para implementação alternativa nos sistemas de automação predial. / This research focuses building automation, analyzing comparatively the use of conventional technologies and other equipments commonly applied in industrial processes. Through a case study, a description of mainly building systems that are feasible to be automated in high technology buildings has been made, including a comparative evaluation of mainly building systems based on conventional systems and automation process, allowing the most efficient use of building resources, beyond to increase the users’ comfort and security. It was verified a great potential for applications of industrial processes automation systems, as an alternative implementation in building automation systems.