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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.
231

Water Resource Alternatives for Power Generation in Arizona

Smith, Stephen E., DeCook, K. James, Fazzolare, Rocco A. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / An examination of potential water sources for power plant cooling in Arizona is presented along with information pertinent to Arizona's future water needs relative to electrical usage growth. It has been projected that Arizona's peak electrical power demands in 1980 and 1990 will exceed that of 1970 by some 5000 megawatts and 16000 megawatts of electricity respectively. At present, the bulk of the electrical energy generated in the western states originates at hydroelectric installations. Utilization of nuclear reactors for power generation requires a larger amount of cooling water than is required for a comparable fossil-fueled plant. It is suggested that the utilization of reclaimed wastewater for cooling purposes is a viable and attractive alternative to groundwater pumpage from both economic and ecological standpoints. Savings arise from conservation of fuel normally required for well pumps, costs of well construction are not required, quantities of fresh water should be released for consumption by alternate users, and a previously unused resource would be effectively recycled.
232

Licenciamento ambiental e a difusão de conflitos: um estudo multicaso a partir de projetos hidrelétricos do Estado do Paraná / Environmental licensing and the diffusion of conflicts: a multiple case study of hydroeletric projects in the state of Paraná

Gomes, Flávia de Faria 06 February 2017 (has links)
CAPES; Fundação Araucária / O obstáculo intrínseco a produção de energia no Brasil possui relação com embates sociais, devido aos impactos produzidos pelas técnicas e tecnologias do setor. Foi estimulada, então, a criação de políticas para mitigá-los, à exemplo da Política Nacional do Meio Ambiente que, para esta função, dispõe de seu principal instrumento, o licenciamento ambiental. Contudo, os conflitos ainda persistem. Diante disso, objetiva-se revelar os aspectos que envolvem o conflito ambiental em torno de projetos de pequenas centrais hidrelétricas, inseridos na primeira fase do processo de licenciamento ambiental, do estado do Paraná – a fim de que se compreenda a origem desses impactos no campo de geração de energia do estado. Para tal fim, esta dissertação fundamenta-se em uma abordagem multicaso, considerando as pretensões do estado para o setor energético e as manifestações promovidas, já que se objetiva estudar os casos complexos, dependentes de estudos de impacto ambiental e de audiências públicas. O estudo possui natureza aplicada, objetivo explicativo e utiliza-se da técnica de análise qualitativa e quantitativa, com auxílio do software ATLAS.ti. Como resultado, obteve-se a compreensão de que os conflitos ambientais estudados emergem do descumprimento das normas do campo energético – orientado pelo avanço do setor privado, pela flexibilização do Estado e por interesses econômicos. Os estudos de caso demonstraram que essa conjuntura se constitui de três dinâmicas: arbitrariedades, enfrentamentos e desdobramentos. A primeira desestrutura os processos de licenciamento ambiental; a segunda promove a criação e/ou o ajuste das normas, diminuindo as resistências sociais; e a terceira refere-se às consequências do embate entre as dinâmicas anteriores. Contudo, mantém-se a importância do instrumento, que não apresenta problemas quanto à sua estrutura, mas, quanto ao tipo de gestão empregada em suas fases – geralmente influenciada por interesses externos. / The intrinsic obstacle to energy production in Brazil is related to social conflicts, due to the impacts produced by the techniques and technologies of the sector. The creation of policies to mitigate them was stimulated, as was the case with the National Environmental Policy, which, for this purpose, has its main instrument, environmental licensing. However, the conflicts persist. In view, the objective is to uncover the aspects that surround the environmental conflict around small hydroelectric power plant projects, inserted in the first phase of the environmental licensing process of the state of Paraná. In this sense, it is sought to understand the origin of their impact on the community directly affected and on investment and power generation involved. In order to do so a multiple case study approach - the projects were selected according to the state of Paraná's pretensions for the energy sector, and considering the cases that have more conflicts, since the objective is to work with complex cases and studies that depend of environmental impact and its respective report, consequently of public hearings -; of applied nature; explorative objective and with regard to data processing, this research adopts qualitative and quantitative analysis techniques with the help of the software ATLAS.ti. As a result, it was understood that the environmental conflicts studied emerge from noncompliance with the norms of the energy field - driven by the advancement of the private sector, by the flexibility of the State and by economic interests. The case studies have demonstrated that this conjuncture consists of three dynamics: arbitrariness, confrontation and unfolding. The first structure the environmental licensing processes; The second promotes the creation and / or adjustment of standards, reducing social manifestations; And the third refers to the consequences of the clash between the previous dynamics. However, the importance of the instrument remains, which presents no problems with its structure, but with the type of management used in its phases - usually influenced by external interests.
233

Licenciamento ambiental e a difusão de conflitos: um estudo multicaso a partir de projetos hidrelétricos do Estado do Paraná / Environmental licensing and the diffusion of conflicts: a multiple case study of hydroeletric projects in the state of Paraná

Gomes, Flávia de Faria 06 February 2017 (has links)
CAPES; Fundação Araucária / O obstáculo intrínseco a produção de energia no Brasil possui relação com embates sociais, devido aos impactos produzidos pelas técnicas e tecnologias do setor. Foi estimulada, então, a criação de políticas para mitigá-los, à exemplo da Política Nacional do Meio Ambiente que, para esta função, dispõe de seu principal instrumento, o licenciamento ambiental. Contudo, os conflitos ainda persistem. Diante disso, objetiva-se revelar os aspectos que envolvem o conflito ambiental em torno de projetos de pequenas centrais hidrelétricas, inseridos na primeira fase do processo de licenciamento ambiental, do estado do Paraná – a fim de que se compreenda a origem desses impactos no campo de geração de energia do estado. Para tal fim, esta dissertação fundamenta-se em uma abordagem multicaso, considerando as pretensões do estado para o setor energético e as manifestações promovidas, já que se objetiva estudar os casos complexos, dependentes de estudos de impacto ambiental e de audiências públicas. O estudo possui natureza aplicada, objetivo explicativo e utiliza-se da técnica de análise qualitativa e quantitativa, com auxílio do software ATLAS.ti. Como resultado, obteve-se a compreensão de que os conflitos ambientais estudados emergem do descumprimento das normas do campo energético – orientado pelo avanço do setor privado, pela flexibilização do Estado e por interesses econômicos. Os estudos de caso demonstraram que essa conjuntura se constitui de três dinâmicas: arbitrariedades, enfrentamentos e desdobramentos. A primeira desestrutura os processos de licenciamento ambiental; a segunda promove a criação e/ou o ajuste das normas, diminuindo as resistências sociais; e a terceira refere-se às consequências do embate entre as dinâmicas anteriores. Contudo, mantém-se a importância do instrumento, que não apresenta problemas quanto à sua estrutura, mas, quanto ao tipo de gestão empregada em suas fases – geralmente influenciada por interesses externos. / The intrinsic obstacle to energy production in Brazil is related to social conflicts, due to the impacts produced by the techniques and technologies of the sector. The creation of policies to mitigate them was stimulated, as was the case with the National Environmental Policy, which, for this purpose, has its main instrument, environmental licensing. However, the conflicts persist. In view, the objective is to uncover the aspects that surround the environmental conflict around small hydroelectric power plant projects, inserted in the first phase of the environmental licensing process of the state of Paraná. In this sense, it is sought to understand the origin of their impact on the community directly affected and on investment and power generation involved. In order to do so a multiple case study approach - the projects were selected according to the state of Paraná's pretensions for the energy sector, and considering the cases that have more conflicts, since the objective is to work with complex cases and studies that depend of environmental impact and its respective report, consequently of public hearings -; of applied nature; explorative objective and with regard to data processing, this research adopts qualitative and quantitative analysis techniques with the help of the software ATLAS.ti. As a result, it was understood that the environmental conflicts studied emerge from noncompliance with the norms of the energy field - driven by the advancement of the private sector, by the flexibility of the State and by economic interests. The case studies have demonstrated that this conjuncture consists of three dynamics: arbitrariness, confrontation and unfolding. The first structure the environmental licensing processes; The second promotes the creation and / or adjustment of standards, reducing social manifestations; And the third refers to the consequences of the clash between the previous dynamics. However, the importance of the instrument remains, which presents no problems with its structure, but with the type of management used in its phases - usually influenced by external interests.
234

Posouzení výhodnosti výstavby přečerpávací vodní elektrárny velkého výkonu v lokalitě Cukrová bouda, okres Šumperk / The assessment of advantages of construction of large hydroelectric power plants in the area of Cukrova bouda, district Sumperk

Knápek, Michal January 2012 (has links)
The subject matter of the master´s thesis is, in particular, an evaluation of the advantageousness of the construction of a pumped-storage hydroelectric power station in the vicinity of Cukrová Bouda. In the master´s thesis introduction the utilisation of pumped-storage hydroelectric power stations in providing reserve power generation to the operator of a power transmission system is discussed. The thesis then focuses on a technical design solution where two alternatives are drawn up for which the nominal parameters of individual designs for a pumped-storage hydroelectric power station are specified. The following part deals with the impact of the structure and the plant’s subsequent operation on the environment. A further key part is the determination of investment and subsequent operating costs and an evaluation of the plant according to economic pointers. The final part of the master´s thesis contains a SWOT analysis and an assumed programme of works for the plant’s preparation and actual construction. The conclusion contains an overall evaluation.
235

Možnosti využití alternativních decentralizovaných zdrojů energie / Possibility of using alternative decentralized energy sources

Pitron, Jiří January 2014 (has links)
The thesis concerns of the possibility by using alternative decentralized sources of energy. The first chapter describes current energy situation in the Czech Republic and consideration of future electrical energy consumption and the coverage by the renewable sources. Another part of this chapter describes each types of renewable energy with their advantages and disadvantages related to the Czech Republic. In the second chapter are introduced inputs which are appropriate for the plan of energetic system. The following theoretical chapter deals with each types of alternative energy sources using renewable source including the possibility of the installation and plan for the building. These alternative sources are sorted out by the way of using renewable sources of energy. The theoretical-practical fourth chapter concerns of the heating by the heat pump. For the detailed description was chosen the heat pump which is currently denote as appropriate alternative source of heat in household. With appropriate plan, which the thesis deals with, is this alternative source considered as proper investment. In the last chapter was assembled programme for creating models of energetic flux and calculation for the plan of heating by the heating pump air/water. This model is taken for concrete buildings related to exact outdoor temperature from previous years in concrete locality. In the end was realized validation of the software with the real measurement in concrete building.
236

Temperatur- och flödesberoende beteende i anslutning till lek hos harr (Thymallus thymallus) i Indalsälven / Temperature- and flow dependent behaviour of grayling (Thymallus thymallus) in Indalsälven during spawning season

Sjöström, Daniel January 2023 (has links)
Vattenkraftens påverkan på rinnande vatten är välbeskriven i litteraturen. Med ökat intresse för vindkraft och andra energislag med begränsad klimatpåverkan, ökar även behovet av reglerkraft. Effekten av korttidsreglerad vattenkraft på ekosystem är ett aktuellt ämne med kunskapsluckor i stort behov av fler studier. Indalsälven passerar Järkvissle kraftverk några mil norr om Sundsvall. Den lokala harrpopulationen har minskat kraftigt och misstankar finns om kopplingar till korttidsregleringen i Järkvissle kraftverk. Vid förvaltning av ekosystem och djuren i dem är kunskapen om interaktioner och beteenden bland det viktigaste att etablera. Detta för att kunna avgöra om artens beteende påverkas av korttidsreglering. Bristande kunskap om lokala lekbeteenden innebar således att harren nedan Järkvissle kraftverk studerades inför förväntad lekperiod. Studien baserades på två antaganden 1) harr förflyttar sig uppströms mot grundområden, lämpade för lek, när vattentemperaturen ökar. 2) harr är mer aktiv när flödesvariationen är hög, eftersom lekplatsernas beskaffenhet påverkas av flödesförhållanden. Harr (n = 20) från sträckan nedan Järkvissle kraftverk märktes med radiosändare, för att studera rörelsemönster och beteenden i anslutning till lek under perioden 28 april till 29 maj 2022. Vid 24 handpejlingstillfällen registrerades de märkta individernas position och djup. En Multipel linjär regression med bakåtvänd eliminering gav tre signifikanta resultat. Det observerades en ökad aktivitet i form av euklidisk förflyttning vid höga flöden motsvarande en förflyttning om 1,0 m (± 1 m) för varje 1,0 m3 s-1 ökat flöde. Det observerades även ett temperaturberoende val av ståndplats där en ökning om 1,0 ºC resulterade i en förflyttning till en ståndplats som var 0,21 ± 0,03 m grundare, på ett avstånd som var 65,2 ± 12,5 m längre bort från dammen. Studien bör kompletteras med kartläggning av optimala värden för flödesförändring som gynnar harr, samt om det finns andra variabler som bättre kan förutse tidpunkt och plats för lek. Om avsikten är att stoppa minskandet av harrbeståndet i Järkvissle, bör Järkvissle kraftstation övervaka vattentemperatur och anpassa sin flödesregim. Detta för mjukare övergångar mellan högt och lågt flöde samt att flödet hålls stabilt under lek med fyra extra veckors utrymme för inkubering. / The effect of hydroelectric powerplants (HEP) on waterways is extensive and has been well documented in the literature. But with an increased interest in wind power and other green alternatives, a higher demand for regulated hydroelectric power has emerged, so as not to put stress on the electric grid. Hydropeaking and its effect on ecosystems are a hot topic with gaps in knowledge calling for more research. Indalsälven runs through Järkvissle HEP a few miles north of Sundsvall. The local grayling population has seen a large decline and there are suspicions of a connection to the hydropeaking at Järkvissle HEP. When managing ecosystems and the animals within them it is vital to establish a firm understanding of interactions and behaviour. This can be used to determine the effect of hydropeaking on the behaviours of grayling. A lack in knowledge of local spawning behaviour thus led to a study of the grayling2population below Järkvissle HEP leading up to the expected spawning period. The study was based around two assumptions: 1) grayling move upstream towards shallower areas suitable for spawning as the temperature in the water rises, and 2) grayling are more active when the variation in flow is high, because the number of suitable spawning grounds are limited by flow. Graylings (n = 20) in the area below the Järkvissle HEP were tagged with radio transmitters, to study the movement and behaviour exhibited before the expected spawning period between April 28th and May 29th, 2022. On 24 occasions hand tracking was performed and position and depth of the marked individuals were recorded. Through a multiple linear regression with backwards stepwise elimination three significant results were found. There was an observed increase in activity in the form of Euclidean movement represented by a 1,0 m (± 1 m) movement for every 1,0 m3 s-1 of increased flow. We also observed a temperature dependency when it came to habitat choice, where an increase of 1,0 ºC in water temperature resulted in a movement to an area 0,21 ± 0,03 m shallower, at a distance that was 65,2 ± 12,5 m further from the dam. The findings of this study should be expanded upon with further research into optimal values for flow variation that best suit grayling, and additionally explore whether there are other variables to better predict time and place for spawning. If the intention is to stop the decline of the grayling population, Järkvissle HEP should monitor the water temperature and adapt their flow regime to make softer transitions between high and low flow and keeping the flow at a stable interval during spawning and an additional four weeks to leave room for incubation.
237

[pt] HIDRELÉTRICAS NA AMAZÔNIA BRASILEIRA: IMPACTOS NO CUMPRIMENTO DA META DE DESMATAMENTO DO ACORDO DE PARIS / [en] HYDROELECTRIC PLANTS IN THE BRAZILIAN AMAZON: IMPACTS IN ACHIEVING THE GOAL OF ZEROING ILLEGAL DEFORESTATION AS ESTABLISHED IN THE PARIS AGREEMENT

DIOGO VIANA GRION VELASCO 18 November 2019 (has links)
[pt] Hidrelétricas no Brasil são responsáveis por gerar grandes impactos ambientais que inclui o aumento dos níveis de desmatamento principalmente quando são instaladas em regiões com floresta. A Floresta Amazônica concentra a maior parte do potencial hídrico brasileiro que ainda não foi aproveitado para geração de energia, por esse motivo essa dissertação dedica-se a analisar a influência da estrutura procedimental da implementação das hidrelétricas no Brasil no alcance da meta de zerar o desmatamento ilegal na Amazônia Brasileira até 2030, que foi estabelecida no Acordo de Paris em 2015. A análise identifica duas principais etapas no processo de implementação de hidrelétricas no Brasil, a etapa de planejamento de expansão da geração de energia e a etapa do licenciamento ambiental. Foram examinados como estudos de casos os projetos de implementação das hidrelétricas dos Complexos de Belo Monte e de São Luiz do Tapajós para verificar a influência das etapas do planejamento e do licenciamento sobre o aumento dos níveis de desmatamento nas regiões afetadas pelos projetos. Verifica-se que as limitações e as deficiências dos estudos de viabilidade ambiental, constantes na etapa do licenciamento, para mitigar o desmatamento associado as hidrelétricas são oriundas de conflitos e inconformidades com fases presentes na etapa do planejamento, como nos estudos de Inventário Hidrelétrico das bacias hidrográficas e Análise Ambiental Integrada da alternativa selecionada. / [en] Hydroelectric plants in Brazil are responsible for major environmental impacts including the increase of deforestation levels in forest regions. Particularly, the Amazon Forest concentrates most of the Brazilian nonexplored energy potential. Therefore, this thesis is dedicated to analyze the influence of the procedural structure of the implementation of hydroelectric dams in Brazil in achieving the goal of zeroing illegal deforestation in the Brazilian Amazon until 2030, which was established in the Paris Agreement in 2015. The analysis consists of identifying two main stages in the process of implementation of hydroelectric plants in Brazil, i.e. the planning for power generation expansion and the environmental licensing. Furthermore, the implementation projects of Belo Monte and São Luiz do Tapajós hydroelectric complexes were examined to verify the influence of the planning and licensing stages on increasing deforestation levels in the regions affected by these projects. It was verified that conflicts and nonconformities regarding Hydraulic Inventory and AAI studies step contained in the planning stage, limit the environmental feasibility studies, in the licensing stage, which is responsible for mitigating the deforestation associated with the hydroelectric plants.
238

Alternativní řešení a pevnostní kontrola mechanických česlí / Alternative solution and strength check of mechanical screens

Sommer, Matěj January 2020 (has links)
This master’s thesis deals with a new design of bar screens. The goal was to come up with an alternative design to already existing device by INKOS a. s. In the first part, there is a summary of various machines working in similiar conditions. The insights gained by this research influenced the design of the new device. It utilizes well proven solutions from previous projects, but some of these were reworked and a few new functions were added. Second part of the thesis describes the analytical solutions, which were used to determine the forces in the assembly during the operation of the device. Based on the results of these calculations, a strength analysis of important components was performed using the finite element method. The result of this thesis is the design and optimization of new bar screens, including engineering drawings and tools for its further development.

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