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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.
41

Vyhodnocení efektivnosti investic obnovitelných zdrojů energie na příkladu malých vodních elektráren / Evaluation of Investment Effectiveness on the Field of Renewable Sources by the Examples of Small Hydro Plants

Pavlíčková, Eva January 2011 (has links)
Thesis deals with the use of renewable sources of energy focused on water energy, especially small hydropower plants in Czech Republic. It should clarify the legal and technical framework for energy production in small hydro power plants, types of aid and the amount for the operator. Case studies describe the construction and reconstruction of small hydroelectric power plants which are dependant on the amount of feed-in tariffs and try to find out the economic efficiency according to the selected methods of investment appraisal.
42

Market Requirements for Pumped Storage Profitability : Expected Costs and Modelled Price Arbitrage Revenues, Including a Case Study of Juktan

Salevid, Karin January 2013 (has links)
The rapid integration of intermittent renewable energy sources (IRES) has caused a growing demand for power system flexibility on energy markets all over Europe. Being the only commercially proven large scale energy storage technology, pumped storage hydro power (PSHP) has by several studies been suggested as an efficient solution to miti­gate the impact of IRES. However, despite the perceived technical demand profit­ability remains as a major obstacle for PSHP development. In this study, a market requirement for PSHP profitability, defined in terms of price volatility, is pre­sented. Considering capital and operational expenditures as well as modelled potential price arbitrage revenues for a greenfield PSHP plant, it may be used as a tool for initial assessments of PSHP profitability in relation to market outlooks or modelled future prices. The results have further been used in a case study, where the price volatility required to motivate a restora­tion of the now decommissioned Swedish PSHP plant Juktan has been determined. The results show that the high capital expenditures characterising PSHP development do comprise in a high risk for developers; while feasibility depends on the sustainment of a highly volatile price climate during several decades, energy markets are often extremely uncertain.
43

Reconfiguração de redes de distribuição em situações de contingências considerando operação ilhada de PCH / Reconfiguration of distribution network in contingency conditions considering islanded operation of small hydro power plant

Lopes, Guilherme Stivanin 22 August 2014 (has links)
One of the main concerns of the power utilities is secure, continuously supplying electric power to customers, thus meeting so satisfy these as to regulatory requirements. Thus, the proposed paper presents a method of restoring the electric power supply applying the concepts of automatic reconfiguration of the aggregate distribution networks the possibility of islanded operation of small hydro (SHP), since the use of PCH so islanded in certain circumstances, or becomes only, or the best solution to be adopted in a contingency situation in order to reduce the impact of unwanted interruptions. Since the intrinsic decision making process of reconfiguration of distribution networks involves multiple objectives and constraints, the proposed methodology uses the Analytic Hierarchy Process (AHP) method, which is a very useful tool for issues involving multicriteria decision taken. Additionally, case studies for analysis and validation of the proposed methodology are presented. / Uma das principais preocupações das empresas distribuidoras de energia elétrica é garantir, de forma contínua, o fornecimento de energia elétrica aos seus clientes, atendendo assim tanto a satisfação desses quanto às exigências regulatórias. Sendo assim, o trabalho proposto visa apresentar uma metodologia de restabelecimento do fornecimento de energia elétrica aplicando os conceitos de reconfiguração automática das redes de distribuição agregados a possibilidade de operação ilhada de pequenas centrais hidroelétricas (PCHs), uma vez que a utilização de PCH de forma ilhada, em determinadas circunstâncias, torna-se ou a única, ou a melhor solução a ser adotada em uma situação de contingência com o objetivo de reduzir o impacto causado por interrupções indesejadas. Visto que a tomada de decisão intrínseca ao processo de reconfiguração das redes de distribuição envolve vários objetivos e restrições, a metodologia proposta utiliza o método Analytic Hierarchy Process (AHP) que representa uma ferramenta muito útil para questões envolvendo tomadas de decisão multicriteriais. Adicionalmente, são apresentados estudos de caso para análises e validações da metodologia proposta.
44

Problemas sociais e institucionais na implantação de hidreletricas : seleção de casos recentes no Brasil e casos relevantes em outros paises / The social and institutional problems of hydro power dams and projects : selection of recent cases in Brazil and in another countries

Pinheiro, Maria Fernanda Bacile 14 February 2007 (has links)
Orientador: Arsenio Oswaldo Seva Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-09T01:58:31Z (GMT). No. of bitstreams: 1 Pinheiro_MariaFernandaBacile_M.pdf: 4359236 bytes, checksum: 7bd15ce5870579751ed1f36e487a1957 (MD5) Previous issue date: 2007 / Resumo: Esta dissertação procura selecionar e estudar casos de projetos de hidrelétricas construídas em outros países, durante o século XX e no Brasil, desde 2002 até a presente data; além de identificar os problemas sociais e institucionais nestes casos selecionados. Para isso, o texto inicialmente discute as mudanças ocorridas no setor elétrico brasileiro, introduzindo informações sobre a formação e mudanças da indústria elétrica brasileira, as empresas representativas da indústria hidrelétrica, e a reestruturação e reconstrução do setor elétrico brasileiro; assim como as mudanças para o território e sociedade nas regiões de implantação e de projetos de usinas hidrelétricas. Em seguida, este trabalho estuda casos relevantes de usinas hidrelétricas selecionadas em outros países, com destaque para a usina hidrelétrica binacional Yacyretá, no rio Paraná, Argentina/Paraguai. Para o estudo dos casos nacionais, foram selecionadas algumas hidrelétricas que tiveram suas represas formadas entre 2003 e 2006; uma hidrelétrica de pequeno porte, onde foi realizado um estudo de caso, a PCH Mosquitão, no rio Caiapó, GO; e outros casos de projetos de hidrelétricas incluídos nos leilões de energia feitos pela ANEEL em 2005 e 2006. Ao fazer um tipo de análise comparativa a partir dessas situações, pôde-se verificar a presença da ¿dam industry¿ tratando com descaso os problemas sociais que envolvem a implantação das hidrelétricas. Conclui-se o trabalho afirmando-se que as dificuldades encontradas pelo governo e pela ¿dam industry¿ para a implantação de usinas hidrelétricas no Brasil são crescentes, mas que estes agentes permanecem com força nas suas tentativas para implantação de novos projetos / Abstract: Hydro power plants, which were constructed in several countries, during century XX, and in Brazil, since 2002, are evaluated in this thesis, as far as their social and institutional problems are concerned. Initially, the evolution of the Brazilian electric power industry is discussed, with emphasis on the role played by the companies making up the so-called ¿dam industry¿, the recent re-organization of the Brazilian power sector; and the social changes that have been occurring in the regions the hydro power plants have been implemented, or are planned to be built. Next, some selected cases of hydro power plants in other countries were studied, with special attention for the binational Yacyretá Hydro Power Plant, in the Paraná river, border between Argentina and Paraguay. For the Brazilian study-cases, some dams formed between 2003 and 2006 were selected; together with a Small Hydro Power Plant named Mosquitão, located at the river Caiapó, in the State of Goiás, and some projects included in the auctions of hydro power plant concessions carried out by the Brazilian power sector¿s independent regulatory agency (ANEEL) in the years 2005 and 2006. A comparative analysis of these cases revealed that the ¿dam industry¿ does not deal fairly with the social problems related to the hydro power plants. The thesis is concluded showing the increasing difficulties faced by the government and the ¿dam industry¿ to build new hydro power plants in the country, despite all their efforts / Mestrado / Mestre em Planejamento de Sistemas Energéticos
45

Inventering av olika mätare för Stuguns vattenkraftverk

Söder, Peter January 2017 (has links)
Det finns många sensormetoder för vattennivåmätning ute på marknaden idag. Målet för forskningsstudien är att presentera och jämföra några av de mätningsmetoder som finns på marknaden för nivåmätning. I studien jämförs modellerna för trycksensorer, flytsensorer, ultraljudssensor och elektromagnetisk sensor för att sedan se vilken sensor som passar bäst för just mätningar av vattennivåer. Genom, datainsamlingen från sök motorerna Google scholar och Mittuniversitetets egen databas Primo har fakta samlats. Informationen har sedan bearbetas och jämförts mot behoven från Vattenfall som ska göra tre sensorbyten på vattenkraftverket i Stugun. Resultatet av studien visade slutsatsen att utifrån kravspecifikationerna Vattenfall gav så var en trycksensor det bästa alternativet för Stugun. Studien gjorde så att Vattenfall köpte in tre stycken Waterpilot FMX21, 22 mm som sedan sattes på plats och kalibrerades. / There are many sensor methods for water level measurement on the market today. The aim of the research study is to present and compare some of the measurement methods available on the market for level measurement. In the study, the models for pressure sensors, flow sensors, ultrasonic sensors and electromagnetic sensors are compared to see which sensor is most suitable for precise measurements of water levels. Through the data collection from the search engines Google scholar and Mid University of Sweden own database Primo, facts have been gathered. The information has since been processed and compared to the needs of Vattenfall, which will do three sensor changes at the Stugun hydropower plant. The result of the study showed that according to the requirement specifications of Vattenfall, a pressure sensor was the best alternative for Stugun. The study resulted in Vattenfall purchasing three Waterpilot FMX21, 22 mm, which were then put in place and calibrated.
46

Podnikatelský záměr - rozšíření stávající výroby elekrické energie z obnovitelných zdrojů za účelem zisku / Business Plan - Extension of Existing Production of Electricity from Renewable Resources to Achieve Profits

Vochtová, Michaela January 2016 (has links)
This thesis deals with the extension of existing electricity production from renewable energy sources. Labour proposes and describes the construction and technical arrangements achieved by increasing production and profits. All analysis and calculations based on the current state of an existing company.
47

Tvorba a estimace modelu malé vodní elektrárny v programu PSCAD / Creation and estimation of small hydro power plant model in PSCAD

Razyapova, Aygul January 2016 (has links)
This thesis focused on creating a model of a small hydropower plant model (SHPP) and a part of the electricity network in the simulation software "PSCAD" (basing on real sources). The model will be specified on the basis of the data obtained from the measurements to correspond with the real equipment.
48

Návrh rekonstrukce jezu Přízřenice na řece Svratce / Reconstruction of the Přízřenice weir at the Svratka river

Trněný, Michal January 2017 (has links)
The Diploma Thesis deals with the design of rekonstruction of the controlled weir ´´Prizrenice“ on the river Svratka to a new gate weir structure. The first part focuses on teoretical intro and the processing of data on the area of interest and the selection of appropriate design solution for the reconstruction of the weir, where there are described several types of movable gate. As a part of sollution, there will be design of small hydro power station. At the end of this part the current condition of the buildings and the channel of the Svratka river in the area of interest is evaluated. In the second part, the Thesis deals with the design of the gate weir structure and its subsequent assessment. At first, the solid substructure and the height of the gate is designed and assessed. Subsequently, the stilling basin is designed and in conclusion, the overall stability of the designed structure is assessed.
49

Sustainability Comparison between EnDev and not-EnDev Micro-Hydro Power (MHP) in Indonesia : Analysis of the long-term technical, social, environmental and economic sustainability of the rural energy infrastructure of MHP in Indonesia

Ranzanici, Andrea January 2013 (has links)
The Energising Development (EnDev) initiative, for which the GIZ acts as implementing agency, promotes the supply of modern energy technologies to households and small‐scale businesses in the rural communities of 24 countries in Africa, Latin America and Asia. In Indonesia, this has been achieved through off‐grid micro‐hydro (MHP) and solar power mini‐grids and since 2006 230 MHP and 117 solar projects have been supported to varying degree at substantial cost, reaching more than 167 thousand people. The objective of this study is to assess this contribution of the EnDev-Indonesia initiative regarding the MHP performance and ultimate long‐term sustainability prospect of the rural energy infrastructure in the country. As such a comparison between EnDev and non-EnDev MHP projects in the country was undertaken and based on the established Key Performance Indicators (KPIs) survey methodology and the DB&TO sustainability model specifically fashioned for the purpose of this study. This approach involved on‐site visits and comprises technical, social, economic and environmental aspects. As a result, the analysis has shown important differences among the different supporting schemes, with the second implementing phase (2009‐2012) of EnDev outranking the other systems largely due to the high level of technical sustainability achieved by these sites. Such a good performance is even more surprising considering that the EnDev1 sites implemented during the first phase of the program in the early years were among the least‐sustainable investigated in this study. However, despite the high costs necessary to reach such a high level of sustainability as regards the quality of the civil works and electro‐mechanical equipments, this aspect alone was found not enough to guarantee the long‐term sustainability of MHP in Indonesia. On the other hand, lack of social and economic sustainability appeared having fatal consequences onthe operations of many plants. Therefore, such complex interrelation among the different aspects of sustainability was investigated and also external factors, like the regional and cultural differences among the different beneficiaries, were addressed. Finally, recommendations for future eventual courses of action were proposed.
50

Är fiskpassage storleksberoende och påverkas den av vattentemperatur, flöde och säsong? : En undersökning baserad på data från en fiskräknare i Bulsjöån / Is there a size-dependency of migrating fish and is it influenced by water temperature, waterflow and seasonality? : A study based on data from a fish counter in Bulsjöån

Jonker, Marjo January 2022 (has links)
Today, many migrating fish stocks find it difficult to reach their breeding grounds. This is because there are different types of obstacles e.g., hydropower plants and dams. Such power plants need environmental adaptations and fish counters are becoming an increasingly common tool for such adaptations. This essay investigates, with the help of data from a fish counter, whether there is a size- dependency and how it is affected by water temperature, water flow and seasonality. The results can contribute with knowledge about how fish counters can be used for evaluation of environmental adaptations of hydropower plants and dams. The highest migration intensity was noted during three migration periods; spring (March – April), summer (June-July) and autumn (September – November) and all differed in intensity.  The average intensity of migration in autumn was nine times higher than spring and three times higher than summer. In addition, more large fish migrated in autumn than in spring and summer. However, autumn showed no significant correlation between the size of the fish and prevailing waterflow and water temperature at the time of passage. In summary, the results show that there may be a need to increase water discharge in the autumn as both the migration intensity and the length distribution were the highest. The use of a fish counter can in the future give the operator good conditions to environmentally monitor their surroundings. To ensure the quality of the data, it is recommended to plan well in advance, ensure the right settings from the beginning and perform regular supervision. The person in charge should also have sufficient knowledge in order to be able to recognize any oddities in the data of the fish counter. The results should also be supplemented with other studies, which concern both downstream and upstream migration, and that the observations are repeated for several years to investigate the significance of mid-year variation. / Idag har många migrerande fiskbestånd svårt att nå till sina reproduktionsplatser. Detta beror på att det finns olika typer av hinder (exempelvis vattenkraftverk och dammar) som gör det svårt för fiskarna att komma fram. Sådana kraftverk behöver miljöanpassas och fiskräknare blir ett allt vanligare verktyg för att följa upp sådana miljöanpassningar. Denna uppsats undersöker, med hjälp av data från en fiskräknare, om fiskvandringen är storleksberoende och hur den påverkas av vattentemperatur, vattenföring och säsong. Resultaten kan bidra med kunskap om hur fiskräknare kan användas vid utvärdering av miljöanpassningar av vattenkraftverk och dammar. Den största fiskvandringsintensiteten noterades under tre vandringsperioder; vår (mars – april), sommar (juni-juli) och höst (september-november). Höstens genomsnittliga vandringsintensitet var ca nio gånger högre än på våren och tre gånger högre än på sommaren. Dessutom vandrade fler stora fiskar på hösten än under våren och sommaren.  Under hösten fanns det dock inget signifikant samband mellan fiskens storlek och rådande vattenflöde och vattentemperatur vid passagetillfället. Sammanfattningsvis visar resultatet att det kan finnas ett behov av att öka vattentappningen på hösten då både vandringsintensiteten och längdfördelningen är som störst för fiskarna. Användningen av en fiskräknare kan i framtiden ge verksamhetsutövaren goda förutsättningar att miljöbevaka sin omgivning. För att kvalitetssäkra datan är rekommendationen att planera arbetet i god tid, ställa in rätt inställningar från början och att utföra regelbunden tillsyn. Den ansvarige bör också vara tillräckligt införstådd för att kunna känna igen eventuella konstigheter i fiskräknarens data. Resultaten bör även kompletteras med andra studier, som rör både nedströms och uppströms vandring, samt att observationerna upprepas under flera år för att undersöka betydelsen av mellanårsvariation.

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