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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.
31

Analýza nesrovnalostí malé vodní elektrárny Beneš. / Contradictions analysis of small water power Beneš.

Kuchař, Jan January 2009 (has links)
This master‘s thesis deals with small water power plant Beneš. The first part of the thesis tries to find causes of low efficiency of this power plant. The second part contains suggestions of construction changes for increasing of efficiency – design of new runner blades and basic parameters of new distributor.
32

Užití BIM v rámci vodního hospodářství / The use of BIM in water management work

Chládová, Zuzana January 2022 (has links)
This diploma thesis addresses Building Information Management (BIM) and its application in water management. The basis of the work is broad research on BIM. Subsequently, the application of BIM is demonstrated in the construction of a small hydroelectric power plant in the Litovel water management node. To conclude, the added value of using BIM and its possible disadvantages for water management are formulated.
33

Methods and cost of developing farm water power

Wallace, Harry Moore January 1926 (has links)
no abstract provided by author / Master of Science
34

Hydropower in Scotland : linking changing energy and environmental agendas with sustainability outcomes

Nelson, Edward January 2013 (has links)
As the UK energy sector moves to a greater contribution from low-carbon and renewable sources it faces significant challenges in delivering affordability, security of supply and sustainability. Although hydropower in Scotland emerged on a large scale in the mid-20th century against an influential, changing wider context of energy policy, environmental regulation and debate, it is now subject to an evolving renewables agenda. This further shapes the national and scheme level characteristics of hydropower and in turn outcomes for the water environment. Contingent upon these considerations, hydropower regulation must now deliver on EU obligations to protect and improve the ecological status of water bodies, whilst also supporting domestic efforts to meet high profile binding renewable energy targets. Yet, despite an acknowledged potential for energy policy to constrain the delivery of water policy objectives, there is little policy harmonisation between disciplines. As Scotland orientates itself as a leader in Europe on climate change, transitioning to increasing amounts of renewable generation across a handful of technologies, there is a gap in knowledge about how specific renewable policies and trends can influence hydropower sustainability outcomes and regulatory challenges. This thesis therefore contributes an innovative and timely critical examination of the effect a changing wider renewable energy and policy context has on hydropower sustainability in Scotland, at a scheme and national level. This research uses an interdisciplinary, temporal analysis to identify linkages and create dialogue between disciplines and scales, informing the pursuit of sustainable renewable energy through policy and regulation in a changing world. It finds firstly, that the changing national generation mix towards an increased contribution from renewable sources, including potentially intermittent technologies such as wind power, has contributed to an alteration in the operational characteristics and reservoir variability profile of Cruachan pumped-storage scheme, presenting positive outcomes for reservoir littoral habitats. Secondly, it finds that whilst not operating in isolation, renewable energy incentive policies, through their eligibility criteria, financial reward frameworks and timing, influence hydropower characteristics and sustainability challenges, providing trade-offs but also synergies for hydropower regulation. Finally, it finds that there is a degree of divergence in hydropower outcomes and challenges in Scotland and Norway, due to the characteristics and especially interaction of wider contextual elements such as topography, profile of precipitation input, national energy needs and the role of regional and municipal government. By highlighting these linkages, this thesis is of value to energy policy and environmental regulation in Scotland and across the EU, and is seen as a first step in addressing these uncertainties and supporting a more integrated and sustainable hydropower and renewables governance framework.
35

Ekonomické aspekty stanovování minimálních průtoků na vodních dílech na Jizeře. / Economic aspects of setting the minimum flow for water power plants on Jizera river.

Vocel, Martin January 2009 (has links)
There is an obligation to hold a minimal flow when running a water power plant in a current czech legistation. There are environmental reasons to determine the minimum discharge and the way to set it is not valid at the moment. We can see a difference in a type of water power stations when comparing the effects from electric power which is produced in water power plant situated on czech rivers and the damage that does not appear on the environment. The weir type of power plant harms the surroundings mildly except of the possible migration obstacles. But the derivation type makes loss that could be hardly compensate by the produced electricity. Different methods of evaluating the enrironment brinks various results and that is the reason why it is hard to say how much the effects from producing the electricity exceed the benefits arising from instream water or vice versa. The only conclusion that can be said is the advice about including more points of view when setting the minimum flowage.
36

The use of small scale hydroelectric power in South Africa, hydro and economic potential for rural electrification.

Reddy, Devan. 01 November 2013 (has links)
Small hydro generation refers to generating capacity of less than 10 MW with the most common being Run-of-River. In South Africa, the level of rural electrification is approximately 50 percent with most of the energy needs being met with biomass fuels. The purpose of this study was to investigate the hydropotential regions that were identified by Eskom and the Department of Minerals and Energy in 2002 and determine sites for small scale development for rural electrification purposes. Technical and feasible analyses were carried out in order to assess the applicability of this kind of energy generating system. The aim of this study was to consider the Free Basic Electrification policy and Solar Home Systems to assess the electrical demand of rural households and possible funding transfer scheme respectively. Furthermore, to formulate an appropriate methodology that can be used given the available data and resources currently available in South Africa. In total, six sites were identified and analysed in this paper, namely: (1) Berg River at gauge G1H013, (2) Mzimvubu River at gauge T3H008, (3) Orange River at gauge D1H003, (4) Mlambonja River at gauge V1H041, (5) Thukela River at gauge V1H002 and (6) Mkomazi River at gauge U1H005 which are in the Eastern Cape, Western Cape and KwaZulu-Natal Provinces. Flow gauge data were analysed in order to develop monthly mean Flow Duration Curves which were used to determine the design flow, power generation (through Power Duration Curve construction) and renewable energy potentially produced from each scheme. Costing functions were utilised in order to determine the initial capital cost of the system which was used to assess the project’s feasibility. In order to predict potential power output of the schemes, the streamflow and hydraulic head of the six rivers were assessed. The potential renewable energy production ranged from about 240 to 6060 MWh/year. Through this energy production, it was found between 165 and 10100 houses could be electrified depending on the electrical allowance provided. This significantly exceeds existing housing numbers. Costing bands ranged from 3 – 7 R/kWh which was high but within reason based on the community income and the transfer of the Solar Home Systems pricing policy. The results of this study provide a good foundation for future work in the estimation of hydropower potential in South Africa and will hopefully be a stepping stone to better estimation of both technical and exploitable hydropower potential for South Africa. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2012.
37

Migration problems of Atlantic salmon (Salmo salar L.) in flow regulated rivers /

Rivinoja, Peter, January 2005 (has links) (PDF)
Diss. (sammanfattning). Umeå : Sveriges lantbruksuniv. / Härtill 6 uppsatser.
38

Dompter la houille blanche, la construction des barrages au Québec, 1898 à 1963 : un essai sur l'évolution des techniques et sur la place des ingénieurs francophones

Harvey, Bernard January 1998 (has links) (PDF)
No description available.
39

The Constitution of Water Power: Agro-exporters and groundwater scarcity in the Ica Valley and Pampas de Villacurí / La Construcción del Poder Hídrico: Agroexportadores y Escasez de Agua Subterránea en el valle de Ica y Villacurí

Damonte Valencia, Gerardo, Gonzales Negreiros, Isabel, Lahud Vega, Julieta 25 September 2017 (has links)
El boom agroexportador en Ica ha disparado dos procesos interrelacionados: la generación de escenarios de escasez hídrica y la emergencia de un nuevo actor social en la región, el grupo agroexportador. Esto ha generado una reconfiguración de las relaciones sociales y políticas en el espacio local, donde los agroexportadores se han posicionado como el actor dominante en la gestión de los recursos hídricos subterráneos, disputando incluso los esfuerzos de regulación del Estado. Así, la pregunta que guía esta investigación es ¿cómo los agroexportadores han concentrado poder hídrico en Ica? y ¿cómo ejercen este poder? El artículo argumenta que el poder hídrico surge a partir del control del agua subterránea, control que ha recaído en manos del grupo agroexportador gracias a su capacidad de concentrar y ejercer tres dimensiones de poder: la capacidad económica, el conocimiento técnico y la coerción. En el desarrollo de este argumento, se muestra que el dominio de los agroexportadores sobre otros actores y su primacía en el control de los recursos hídricos no son facultades arrebatadas sino otorgadas, siendo legitimada por discursos de eficiencia, desarrollo regional y empleo pleno. / The agro-export boom in the coastal region of Ica has caused two interrelated processes: the generation of water scarcity scenarios and the emergency of the agro-exporter group as a new social actor. The role assigned to agro-exporters in the narrative of regional development has given them a dominant position in the management of Ica water resources. This has generated a re-configurationof social and political relationships at the local space that has allowed them to be able of even contest State’s efforts to regulate groundwater use. Thus, the questions guiding this research are: how the agro-exporter group has concentrated water power in Ica? And how do they exercise this power? This paper argues that control over groundwater resources has fallen into the hands of the agro-exporter group due to their capacity to concentrate and exercise three dimensions of power: economic capacity, technical knowledge and coercion. In developing this argument, we explain how the concentration of these power dimensions has influenced in the production of water scarcity scenarios to certain groups of population, without confronting much resistance despite of it.
40

Análise técnica e econômica de retificadores de corrente para produção de hidrogênio eletrolítico = estudo de caso aproveitando a EVT da UHE de Itaipu / Technical and economical analysis of power rectifiers for electrolytic hydrogen production : case study considering the spilled turbinable energy of Itaipu Hydroelectric Power Plant

Gambetta, Francielle 17 August 2018 (has links)
Orientador: Ennio Peres da Silva / Dissertação ( mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-17T04:55:49Z (GMT). No. of bitstreams: 1 Gambetta_Francielle_M.pdf: 4780185 bytes, checksum: f2071d96fca67109088a5766792577eb (MD5) Previous issue date: 2010 / Resumo: Para países com disponibilidade de energia elétrica relativamente barata, como o Brasil, o custo de instalação é o fator mais importante para a produção de hidrogênio eletrolítico, representando mais de 50% do custo total. O retificador de corrente é um dos principais equipamentos que compõem um sistema de eletrólise da água e é objeto de estudo desta dissertação. A partir de uma análise técnica, concluiu-se que, atualmente, o sistema de retificação mais adequado ao processo de produção de hidrogênio eletrolítico é o sistema a tiristor, principalmente por apresentar maior eficiência e confiabilidade operacional. Por meio de uma análise de mercado, concluiu-se que o mercado nacional, em sua maioria, está apto a fornecer retificadores industriais apenas para aplicação em eletrolisadores unipolares, já o mercado internacional possui uma vasta gama de retificadores com diversos níveis de tensão e corrente de saída, sendo capaz de fornecer estes equipamentos tanto para alimentar eletrolisadores industriais unipolares quanto bipolares. O custo do hidrogênio foi calculado tomando como base estudos anteriores e utilizando a Energia Vertida Turbinável (EVT) da UHE de Itaipu, o que resultou em US$ 2,66/kg para uma planta com capacidade de produzir 4.365 m3/h de hidrogênio. A influência do custo do retificador sobre o custo de produção é de 10,8% e, assim, uma diminuição de 50% no custo deste equipamento promoveria uma redução de 5,4% no custo do hidrogênio eletrolítico. Apesar de pequena, esta redução pode ser determinante em muitos casos. Assim, a introdução de uma linha de pesquisa em um pólo tecnológico para o desenvolvimento destes equipamentos é interessante, pois além de contribuir com a redução do custo do hidrogênio eletrolítico, representa uma oportunidade de crescimento econômico que pode colocar o Brasil em destaque de forma positiva dentro dos cenários energético e econômico mundiais / Abstract: For countries with relatively cheap electricity availability, such as Brazil, the cost of installation is the most important factor for the production of electrolytic hydrogen, representing more than 50% of the total. The power rectifier is one of the main devices comprising the water electrolysis system and it is the object of study in this dissertation. From a technical analysis, it was concluded that currently the most suitable system for electrolytic hydrogen production is the thyristor system, mainly due to its higher efficiency and operational reliability. Through market analysis, it was concluded that most of rectifiers available in the domestic market are designed only for use in industrial unipolar electrolysers. On the other hand, the international market has a wide range of rectifiers with different levels of voltage and current output, being capable of providing such equipment for both industrial unipolar and bipolar electrolysers. The cost of hydrogen was calculated using previous studies of the Spilled Turbinable Energy (STE) of Itaipu Hydroelectric Energy Plant, and resulted in US$ 2.66/kg for a plant with capacity to produce 4,365 m3/h of hydrogen. The influence of the rectifier cost on the gas production cost is 10.8%, and thus a decrease of 50% in the cost of such equipment would promote a reduction of 5.4% in the cost of the electrolytic hydrogen. Although small, this reduction can be decisive in many cases. Thus the introduction of a research line at a technological center for the development of this equipment is interesting, which also contributes to lowering the cost of electrolytic hydrogen and is an opportunity for economic growth to highlight Brazil in the worldwide energy and economic scenery / Mestrado / Mestre em Planejamento de Sistemas Energéticos

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