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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Posouzení připravenosti chovů na výpadky elektrické energie na území ORP Soběslav / Power shortage readiness assessment of animal farms in Soběslav municipality

MUSILOVÁ, Karolína January 2017 (has links)
The importance of electrical energy for a contemporary society is increasing. However, most of people don´t realise possible consequences of power outage for agriculture. This thesis aims at presenting an analysis of power outage effects on agricultural breeding in MEC Soběslav area. Considering the aim of the thesis, there is a problem whether the selected breeding farms are ready enough for power outages. The theoretical part of the thesis characterises crisis management, integrated rescue system (IRS), critical infrastructure and electrical grid. The following part of the chapter deals with livestock, poultry and pig breeding, mainly from the point of view of their technological as well as technical equipment. The research part is based on pen and paper interviews with representatives and owners of breeding farms. The research was focused on a degree of dependency on electrical energy in MEC Soběslav area. Two breeding farms in Germany were selected for a comparison with the situation abroad. The results revealed that most of the breeding farms are strongly dependent on electrical energy. Thanks to the last modernisation, automatic feeding or water supplying became a common standard. Unfortunately, most of the modern breeding farms are not able to guarantee these procedures in case of power outage. Great amount of breeding farms don´t have any emergency sources of energy and those that own some, have only limited supplies of fuel. There are no contracts guaranteeing the fuel for the breeding farms. The most problematic situation concerns poultry breeding, where the breeding procedures are wholly controlled by information systems and even the minute failures cause massive losses. Therefore the research problem was confirmed because the breeding farms are not equipped for powers outages. This diploma thesis is supposed to be used for educational purposes or as the means of orientation in the problem for individual breeders. The purpose is the education of presented subjects.
22

A rede elétrica na cidade de Tefé como instrumento de análise de integração territorial / The grid in the city of Tefé as an analytical tool for territorial integration

Kristian Oliveira de Queiroz 18 October 2011 (has links)
Neste estudo, a rede elétrica é utilizada como instrumento de análise para a integração territorial restrita da cidade de Tefé ao meio técnico-científico-informacional. A ocorrência de interrupções e racionamentos no fornecimento de energia elétrica na cidade, localizada no interior do estado do Amazonas, proporciona prejuízos econômicos, sociais e culturais significativos à população, dificultando seu pleno desenvolvimento. Dessa forma, o conhecimento dos principais eventos da evolução histórica da rede elétrica no território nacional e das políticas de planejamento governamental que corroboraram para o surgimento deste problema é analisado com o propósito de entender as dinâmicas socioespaciais que não facilitam a inserção dessa fração do território ao meio geográfico contemporâneo. Os projetos de integração na fronteira amazônica produziram um crescimento sem planejamento dos objetos técnicos, que, estruturados às pressas, proporcionaram obras imediatistas, realizadas em curto prazo -- o que Milton Santos (1994) chama, para os países subdesenvolvidos, de -saltar etapas?. Isso propiciou à população consequências negativas vinculadas às estruturas sociotécnicas amazônicas, que não atendem integralmente às funções que deveriam realizar, como é o caso da rede elétrica do Amazonas. A realização de uma análise de eventos, projetos e propostas que permitem sugestionar uma mitigação ou solução para esse obstáculo ao exercício do direito à cidadania do tefeense é direcionada nesta pesquisa. / In this study, the grid is used as an analytical tool for the restricted territorial integration in the city of Tefé to the technical and scientific-informational mean. The occurrence of interruptions and shortages in the electricity supply in the city, located within the State of Amazonas, provides significant economic, social and cultural losses to the population, hindering their full development. Thus, the knowledge of the main events of the historical evolution for the electric grid in the country and the government planning policies which confirmed to the emergence of this problem is analyzed in order to understand the socio-spatial dynamics that do not facilitate the insertion of this fraction in the contemporary geographical territory. Integration projects in the Amazon frontier produced an unplanned growth of technical objects, which were structured hastily, providing immediately works made in the short term, which according to Milton Santos (1994) is named by -leap-frog? in developing countries. With that, the population is linked to negative consequences related to the Amazonians socio-technical structures that do not match the functions they should undertake such as Amazon electricity grid. Performing an analysis of the events, projects and proposals allow us to suggest a mitigation or a solution to this obstacle that is related to the exercise of the tefeense citizenship right.
23

Access to electricity and economic development : determinants of favorable impacts for households / Accès à l'électricité et développement économique : déterminants des impacts favorables pour les ménages

Millien, Arnaud 17 September 2019 (has links)
En 2018, environ un milliard de personnes vivaient sans électricité. Or l'extension des réseaux est confrontée à de nombreux défis qui compromettent la soutenabilité de l'électrification traditionnelle. Les Projets d'Electrification Décentralisée (PED) offrent désormais des solutions réalistes pour un accès à l'électricité hors réseau dans les pays en développement. Cette thèse explore le rôle de la demande de fiabilité du service d’électricité comme déterminant d’une extension durable du réseau, et l'efficacité de l'offre d’électricité décentralisée pour l’atteinte des objectifs du développement durable. Avec des données sur les coupures observées par les ménages au Kenya, le premier chapitre établit la préférence des ménages pour la fiabilité du service d'électricité, laquelle pourrait constituer le levier majeur d’une extension efficace du réseau. Dans le deuxième chapitre, une méta-analyse consolidant 112 évaluations de projets décentralisés montre que la technologie, la capacité et la gouvernance supportent les choix de conception les plus déterminants pour atteindre les objectifs du développement durable. Le troisième chapitre explore la gamme d'objectifs atteints par les pratiques de l’électrification décentralisée. Les plus efficaces sont celles qui adressent les utilisations productives et les services publics, ainsi que les micro-réseaux dans les zones éloignées, qui ont des impacts positifs sur l’information et la communication. La probabilité d'impacts positifs augmente avec la capacité des systèmes solaires individuels, qui favorisent la santé et l’éducation. / By 2018, about one billion people were living without electricity. The extension of electrical grids is facing many challenges that jeopardize the sustainability of traditional electrification. Decentralized Electrification Projects (DEP) now offer feasible solutions for offgrid access to electricity in developing countries. This thesis explores the role of the demand for reliability of the electricity service as a determinant of sustainable extension of the electrical grid, and the efficiency of electricity supply by DEP to achieve the sustainable development goals. With data on outages observed by households in Kenya, the first chapter establishes the households' preference for the reliability of electricity service, which could be the major lever for effective network expansion. In the second chapter, a meta-analysis consolidating 112 decentralized project evaluations shows that technology, capacity and governance support the design choices that are most critical to achieving the sustainable development goals. The third chapter explores the range of objectives achieved by decentralized electrification practices. The most effective are those that address productive uses and public services, as well as micro-networks in remote areas, which have positive impacts on information and communication. The likelihood of positive impacts increases with the capacity of solar home systems, which favor health and education.
24

Citlivostní analýza nákladů na výpadky plynoucí z nedodržení zákaznických standardů nepřetržitosti dodávky / Sensitivity analysis of costs on power outages resulting from nonadherence of custom - tailored standards of the continuity of power supply

Polák, Jiří January 2010 (has links)
The goal of the thesis is to describe the approaches used for the regulation of the continuous supply of electric power in the selected countries of European Union and to determine the power outages costs in the specific distribution network, resulting from non-observance of the customer standards used in Great Britain, Sweden and Finland. The costs have been calculated for the entire network, as well as for the individual outputs. The thesis carries out the sensitivity analysis of the power outages costs, resulting from the breaching the supply restoration standards and the multiple interruptions standard used in the Great Britain. The costs of the individual limits are shown in the tables and the graphs. The comparison of the individual outputs according to the height of the penalty costs have been carried out on the selected set of limits. The comparison of the order of the individual outputs is then carried out for the customer standards used in Great Britain, Sweden and Finland.
25

An evaluation of the supplier relationship management and procurement practices at a parastatal: the case of Eskom Holdings Limited

Jonathan, Ellsworth C. January 2014 (has links)
M. Tech. (Department of Logistics Management, Faculty of Management Sciences), Vaal University of Technology. / The primary objective of this study was to investigate the supplier relationship management practices at Eskom. Currently, the challenges faced by the parastatal include diminished reserve margin, increased unplanned generation plant outages as well as coal supply and quality constraints coupled with ever-rising primary energy costs. It is, therefore, evident that as a national asset, Eskom cannot overcome the current challenges successfully without strong partnerships with key suppliers. A framework for supplier management containing four different elements was researched. The first element, which forms the basis for all supplier management operations, is the development of supplier management relationships. The framework also includes supplier collaborations and the various aspects of discovery, supplier pre-selection, and supplier selection, which relate to finding, qualifying, and choosing the best suppliers. Lastly, and also very important was the supplier development and localisation as well as the legislature thereof. A quantitative cross-company survey was conducted using a sample of 260 suppliers, who have been on the database for more than twelve (12) months and who responded to the business requests to update the data on the system. The findings of the study are largely supported by the literature. Finally, the study makes recommendations and highlights further research, managerial, and policy implications.
26

Sistemas fotovoltaicos integrados ao perfil de uso da edificação / Integrated photovoltaic systems to use the building profile

Márcia Rose Alves de Macedo Azzolino Ricetta 08 December 2010 (has links)
Nos últimos anos, o consumo de energia vem crescendo mundialmente nos grandes centros urbanos, e esforços na área de eficiência energética estão sendo implantados, a fim de reduzir o consumo no horário da ponta e interrupções da rede. O aproveitamento das fontes renováveis, como o fotovoltaico em uma edificação se torna um atrativo a mais para a matriz energética num momento em que o país prima pela universalização dos serviços de energia e a classificação de edifícios comerciais, de serviço e públicos, além dos residenciais quanto à eficiência energética através do Procel Edifica (RTQ-C e RTQ-R). Os sistemas fotovoltaicos podem configurar perfis de uso nas edificações de modo a gerar energia para consumo próprio ou ligado à rede e ainda ter influência na arquitetura do prédio com revestimento: os perfis podem está em telhados, fachadas ou janelas, amenizando em alguns casos a carga térmica no prédio com sombreamento arquitetônico. Hoje, com o avanço da tecnologia no setor de armazenagem é possível, o atendimento com segurança e eficiência a uma edificação ou direcionar esta armazenagem a uma demanda específica como o atendimento à demanda de ciclo profundo, tais como, iluminação externa e recarga de veículos elétricos. Partindo da premissa de sistemas interruptos de energia, UPS, uso de fonte secundária como FV, baterias e Flywheel é apresentado uma forma de melhor gerenciar a energia armazenada, podendo estender a vida útil da bateria e conseqüentemente de todo o sistema fotovoltaico na edificação. Esta forma de armazenar energia proporciona um serviço de uso contínuo sem percepção das interrupções da rede com garantia de 20 anos, tal qual o módulo fotovoltaico, com esta proposta as perdas de energia elétrica na edificação serão atenuadas, pois a eletricidade será utilizada de forma eficiente e inteligente. O ponto de partida do estudo de caso no prédio do IBAM são os sistemas fotovoltaicos com geração distribuída (mini-redes) conectados à rede que são instalados para fornecer energia ao consumidor, complementando a quantidade de energia demandada, caso haja algum aumento do consumo de energia na edificação, ou ainda utilizar o sistema fotovoltaico na hora da ponta e interrupções do sistema da rede no período fora da ponta. A estocagem inercial por meio do Flywheel tem um papel fundamental nesta mini-rede (Flywheel, bateria VRLA, UPS, inversor e STS), pois a sua utilização pode ser apontada como uma inovação tecnológica quanto à regulação de tensão no sistema de energia elétrica, além de preparar a edificação para o smart-grid. Esta configuração de acumulação de energia permitiu a analise do deslocamento desta energia armazenada para o consumo no horário de ponta, mudando o conceito de sistemas fotovoltaicos autônomos no meio urbano e rural no país. Este conceito de armazenagem se confirma então como um aporte na eficiência de energia na edificação, podendo carrear economia de energia substancial, além de proporcionar uma confiabilidade no serviço de energia, com um baixo retorno do investimento e com uma garantia de funcionamento com pequena ou nenhuma manutenção durante o período de vida de 20 anos. / In recent years, energy consumption is globally growing in urban centers, and efforts in the area of energy efficiency are being implemented to reduce consumption of this at the time of the tip and grid outages. The use of renewable sources such as photovoltaic in a building becomes a more attractive energy matrix for a moment in which Brazil press for universal energy service and labeling of commercial buildings, service and public and residential on the efficiency energy through Procel Build (RTQ RTQ-C and-R). Photovoltaic systems can be used as coatings on buildings to generate energy for its own or connected to the mini-grid and still have influence on the architecture of the building: the coatings can is in roofs, facades or windows, softening in some cases the thermal load on building with architectural shading. Putting photovoltaic panels on the facades of the building allows us to serve the demand of the load with deep cycle, such as exterior lighting and possibly charging for electric vehicles. Today, with advancing technology in the storage industry is possible to service safely and efficiently in a storage building or direct this to a specific demand. Assuming uninterrupted power systems, UPS, use of secondary sources like PV, batteries and Flywheel is presented a way to better manage the stored energy and can extend battery life and consequently the entire PV system in the building. This way of storing energy provides a service perception of continuous use without interruption of the network with 20-year warranty, like the PV module, with this proposed loss of electricity in the building will be softened because the electricity will be used efficiently and intelligently. The starting point of the case study conducted in a commercial building in Rio de Janeiro is the photovoltaic systems with distributed generation (mini-grids) that are connected to the grid installed to provide power close to consumers, enhancing the amount of energy ofered if there is some increase in energy consumption in the building, or to use the PV system at the time of the tip and the grid system outages during off-peak. The storage through the inertial flywheel has a key role in this mini-grid (Flywheel, VRLA battery, UPS, inverter and STS), because their use can be considered a technological innovation for the voltage regulation in electric power system, and to prepare the building for the smart-grid. The accumulation of power by batteries and Flywheel UPS allowed the analysis of displacement of energy stored for consumption at peak hours, the same being managed by mini-grids, changing the concept of photovoltaic systems in urban and rural areas in Brazil . This form of storage is then confirmed as an intake of energy efficiency in building, as well as for the Brazilian energy matrix. Thus may carry substantial energy savings, and provide a service reliability of power, with a low return on investment and a guarantee of operation with little or no maintenance during the life of 20 years.
27

Sistemas fotovoltaicos integrados ao perfil de uso da edificação / Integrated photovoltaic systems to use the building profile

Márcia Rose Alves de Macedo Azzolino Ricetta 08 December 2010 (has links)
Nos últimos anos, o consumo de energia vem crescendo mundialmente nos grandes centros urbanos, e esforços na área de eficiência energética estão sendo implantados, a fim de reduzir o consumo no horário da ponta e interrupções da rede. O aproveitamento das fontes renováveis, como o fotovoltaico em uma edificação se torna um atrativo a mais para a matriz energética num momento em que o país prima pela universalização dos serviços de energia e a classificação de edifícios comerciais, de serviço e públicos, além dos residenciais quanto à eficiência energética através do Procel Edifica (RTQ-C e RTQ-R). Os sistemas fotovoltaicos podem configurar perfis de uso nas edificações de modo a gerar energia para consumo próprio ou ligado à rede e ainda ter influência na arquitetura do prédio com revestimento: os perfis podem está em telhados, fachadas ou janelas, amenizando em alguns casos a carga térmica no prédio com sombreamento arquitetônico. Hoje, com o avanço da tecnologia no setor de armazenagem é possível, o atendimento com segurança e eficiência a uma edificação ou direcionar esta armazenagem a uma demanda específica como o atendimento à demanda de ciclo profundo, tais como, iluminação externa e recarga de veículos elétricos. Partindo da premissa de sistemas interruptos de energia, UPS, uso de fonte secundária como FV, baterias e Flywheel é apresentado uma forma de melhor gerenciar a energia armazenada, podendo estender a vida útil da bateria e conseqüentemente de todo o sistema fotovoltaico na edificação. Esta forma de armazenar energia proporciona um serviço de uso contínuo sem percepção das interrupções da rede com garantia de 20 anos, tal qual o módulo fotovoltaico, com esta proposta as perdas de energia elétrica na edificação serão atenuadas, pois a eletricidade será utilizada de forma eficiente e inteligente. O ponto de partida do estudo de caso no prédio do IBAM são os sistemas fotovoltaicos com geração distribuída (mini-redes) conectados à rede que são instalados para fornecer energia ao consumidor, complementando a quantidade de energia demandada, caso haja algum aumento do consumo de energia na edificação, ou ainda utilizar o sistema fotovoltaico na hora da ponta e interrupções do sistema da rede no período fora da ponta. A estocagem inercial por meio do Flywheel tem um papel fundamental nesta mini-rede (Flywheel, bateria VRLA, UPS, inversor e STS), pois a sua utilização pode ser apontada como uma inovação tecnológica quanto à regulação de tensão no sistema de energia elétrica, além de preparar a edificação para o smart-grid. Esta configuração de acumulação de energia permitiu a analise do deslocamento desta energia armazenada para o consumo no horário de ponta, mudando o conceito de sistemas fotovoltaicos autônomos no meio urbano e rural no país. Este conceito de armazenagem se confirma então como um aporte na eficiência de energia na edificação, podendo carrear economia de energia substancial, além de proporcionar uma confiabilidade no serviço de energia, com um baixo retorno do investimento e com uma garantia de funcionamento com pequena ou nenhuma manutenção durante o período de vida de 20 anos. / In recent years, energy consumption is globally growing in urban centers, and efforts in the area of energy efficiency are being implemented to reduce consumption of this at the time of the tip and grid outages. The use of renewable sources such as photovoltaic in a building becomes a more attractive energy matrix for a moment in which Brazil press for universal energy service and labeling of commercial buildings, service and public and residential on the efficiency energy through Procel Build (RTQ RTQ-C and-R). Photovoltaic systems can be used as coatings on buildings to generate energy for its own or connected to the mini-grid and still have influence on the architecture of the building: the coatings can is in roofs, facades or windows, softening in some cases the thermal load on building with architectural shading. Putting photovoltaic panels on the facades of the building allows us to serve the demand of the load with deep cycle, such as exterior lighting and possibly charging for electric vehicles. Today, with advancing technology in the storage industry is possible to service safely and efficiently in a storage building or direct this to a specific demand. Assuming uninterrupted power systems, UPS, use of secondary sources like PV, batteries and Flywheel is presented a way to better manage the stored energy and can extend battery life and consequently the entire PV system in the building. This way of storing energy provides a service perception of continuous use without interruption of the network with 20-year warranty, like the PV module, with this proposed loss of electricity in the building will be softened because the electricity will be used efficiently and intelligently. The starting point of the case study conducted in a commercial building in Rio de Janeiro is the photovoltaic systems with distributed generation (mini-grids) that are connected to the grid installed to provide power close to consumers, enhancing the amount of energy ofered if there is some increase in energy consumption in the building, or to use the PV system at the time of the tip and the grid system outages during off-peak. The storage through the inertial flywheel has a key role in this mini-grid (Flywheel, VRLA battery, UPS, inverter and STS), because their use can be considered a technological innovation for the voltage regulation in electric power system, and to prepare the building for the smart-grid. The accumulation of power by batteries and Flywheel UPS allowed the analysis of displacement of energy stored for consumption at peak hours, the same being managed by mini-grids, changing the concept of photovoltaic systems in urban and rural areas in Brazil . This form of storage is then confirmed as an intake of energy efficiency in building, as well as for the Brazilian energy matrix. Thus may carry substantial energy savings, and provide a service reliability of power, with a low return on investment and a guarantee of operation with little or no maintenance during the life of 20 years.

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