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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

Politique optimale pour l'interconnection d'un systeme hydroelectrique a un systeme thermique à l'aide de l'ordinateur digital.

Dupuis, Francis Yvon. January 1972 (has links)
No description available.
42

Small Scale Hydropower-Appropriate Technology for Rural Development in Lesser Developed Countries

Harper, Stephen R. 01 July 1980 (has links) (PDF)
Less Developed Countries (LDC's) now have a total of about 2.8 billion people, or approximately 70 percent of the total world population. World populations and current energy consumption are such that is all the world's countries came up to the U.S. per capita energy use, the world's consumption would multiply by a factor of seven. For the LDC's, energy development will be an increasingly important issue. Hydropower technology is on the shelf, and available now, of proven feasibility both technically and economically, and presents a sound and rational energy solution from the environmental viewpoint. It is a technology which could be useful to the Less Developed Countries for the long term, irrespective of the shift from abundant low-cost fossil fuel options or the development of more exotic alternate energy technologies. With its continuing replenishment and nondepleting characteristics, it remains one of the most attractive sources of energy. The nature of water resources includes a distributive element which makes it ideal for rural development. The apparent shift in development policy, from the traditional "top-down" industrialization approach to the "bottoms-up" reach the village approach, requires decentralized applications of energy resources attainable through development of hydropower in many regions of the world. Distributed Small Scale Hydropower (SSH) systems offer excellent opportunities to augment energy supplies to many rural areas. Also, in a modest way the development of a community infrastructure, training of operating and maintenance personnel, and initiation of small scale agribusiness enterprises may be undertaken. Each of these activities could result in relatively major contributions to the improvement of quality of life. SSH sites are found in abundancy in most mountainous regions and offer sensible possibilities for decentralized applications in LDC's.
43

Optimisation and design of two micro-hydro turbines for medium and low head applications.

Randelhoff, Julian. January 2000 (has links)
The necessity to develop an automated process for the design of micro-hydro power systems was based on the increasing demand for hydropower as a renewable energy source and to develop cost effective power supplies to rural areas. The application of the formula for the design of these systems is then to simplify the selection of the turbine sizing and is made possible by the similarity laws that exist within turbine and pump families. in addition the sizing of the supply and exhaust piping is also a matter of scaling. No selection process of turbine type is included due to the limitations of cost effectiveness and the category of size into which the turbine was specified. Furthermore. a new approach to turbine design was separately undertaken to satisfy low head and low flow-rate conditions. However, it was only designed up to a cost analysis with no manufacturing having been undertaken. The axial flow turbine. which was most suited for micro-hydro was designed and built as a prototype with a standardized mounting frame. The initial conditions used to generare the velocity vectors and angles were specific to the installation site and used to computationally generate the rotor and stator blades. This required an analysis of the different profiles available as well as research into their design. Once the blade profile stacking had been determined, this was translated into a software program that developed the blades from site-specific initial conditions. However, the design of the blades was interdependent on the dimensioning of the rest of the turbine components and designing these in parallel proved to be an intricate task. With the design complete, the turbine was then installed and testing proceeded with the use of pressure gauges and the results of torque and rpm obtained from a dynamometer. Analysis of the results was undertaken and presented in graphical format with comments on both the design and results. / Thesis (M.Sc.Eng.) -University of Natal, Durban, 2000.
44

The economic and policy aspects of small hydro development in British Columbia

Croll, Geoffrey Edward George January 1990 (has links)
Small hydropower offers many advantages as a source of energy and it has been successfully developed by the private sector in the U.S. and in Ontario. Although there is considerable interest in developing British Columbia's vast small hydro resource, there has been very little progress to date. The reasons for this are related more to economic and political factors than to technical issues. In this thesis I review the situation in B.C. and propose a policy framework for energy purchase price, one of the main issues involved in small hydro development. The price offered small hydro producers for their electricity is clearly less than B.C. Hydro's avoided cost, but there is little evidence to support the amount offered. I suggest that, in the absence of an established, competitve market, energy purchase rates should be based on the utility's avoided costs, and that avoided costs be determined by amortizing the capital costs of the next scheduled project over a 20 year period, rather than basing them on the average levelized costs of all future projects. Furthermore, small hydro development should take a two-stage approach, similar to Ontario's, whereby energy is initially purchased at the utility's full avoided cost and later, when the small hydro industry has had a chance to develop, energy would be purchased at market value or through a competitive bidding process. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
45

Cumulative Effects on Human Health within the Hydroelectric Sector: A Case Study of Manitoba Hydro

2015 December 1900 (has links)
The construction and operation of hydroelectric projects consist of multiple activities in a single watershed, which can generate significant impacts on the surrounding biophysical environment and on the health and well-being of local communities. The impacts of those activities may be insignificant individually, yet together may have an important cumulative effect. The impacts of hydroelectric development on human health and well-being have been widely documented. Current practices of cumulative effects assessment (CEA), however, as conducted under project-based environmental assessment (EA), often fail to address the deeper issues of human health and social well-being. This thesis was developed to examine how health effects, including cumulative health effects, are considered within regulatory EA practices in the hydroelectric sector in Manitoba. This was achieved by reviewing the EAs of three recent hydroelectric projects –Wuskwatim Generating Station, Bipole III Transmission Project, and Keeyask Hydroelectric Generating Station – located in the Nelson River watershed in northern Manitoba. Results indicate that the consideration of human health issues in EA has gradually improved over time; however, the assessment of health impacts was invariably limited to physical health components and often lacked due consideration of broader social health issues. The inadequacy of the practice of health impact assessment (HIA) was also evident by the lack of health-related indicators and the poor consistency in the use of indicators across projects and over time for measuring and predicting changes in the health conditions of the communities due to project development. An in-depth analysis regarding the assessment of cumulative health effects was carried out in the CEA of the most recent hydroelectric development – the Keeyask project. The findings show that cumulative health effects were not adequately considered in each of the basic components of CEA – scoping, retrospective analysis, prospective analysis, and management measures. Improving the consideration of health in EA requires paying more attention to broader range of health determinants, including both biophysical and social determinants and their interconnectedness in EA. Moreover, there is a need to improve greater consistency in the use of health indicators across projects and over time. It can be assisted by developing standardized terms of reference (ToR) for project proponents to ensure the consideration and monitoring of those indicators used for development projects built within the same geographic region and affecting the same communities and environments. Approaching cumulative health effects in a more regional and strategic framework of CEA, beyond the scale of individual projects, is likely to provide the best mechanism to understand and monitor the cumulative impacts of project development on the health and well-being of the affected communities.
46

Repurposing a Hydroelectric Plant

Pritcher, Melissa 01 January 2008 (has links)
This thesis project explores repurposing a hydroelectric plant along Richmond Virginia's Canal Walk. The building has been redesigned to create a community-oriented space programmed as an indoor park, event venue space, and cafe. Throughout this thesis, it became important to create private niches within a public space while creating a flexible public venue that accommodates a variety of activities. Through a variety of spaces that offer users options, a flexible public venue is creating, yielding a community-oriented environment that reconnects local with the site.
47

Variações da fauna de mosquitos (Díptera:Culicidae) em área de implantação de uma hidrelétrica no rio Paranapanema, SP/PR / Variations of fauna of mosquitoes (Diptera: Culicidae) in areas of deployment of a dam on river Paranapanema, SP / RP.

Sugimoto, Renato Sinnhofer 04 September 2009 (has links)
Se por um lado as usinas hidrelétricas suprem as necessidades de energia do país, essas também são responsáveis pela proliferação de doenças cujos agentes são transmitidos, em sua grande maioria, por mosquitos que utilizam as áreas inundadas dessas usinas como criadouros. Pode-se observar tal cenário na UHE de Ourinhos, que está localizada no rio Paranapanema entre as cidades de Ourinhos, SP, e Jacarezinho, PR, onde foram definidas três estações de coleta usadas para a avaliação da dinâmica de população nos períodos pré e pós inundação do reservatório, a partir dos dados coletados descreveu-se as alterações ocorridas na população de culicídeos da UHE Ourinhos, diante dos impactos da inundação e calculou-se riqueza, dominância, diversidade e , IAEP e similaridade. Sendo que para captura de adultos utilizou-se armadilha de Shannon e aspirador à bateria, e para os imaturos conchas entomológicas em coleções de água estagnada. Entre as espécies de importância epidemiológica coletadas e identificadas temos: Aedes albopictus, Aedes scapularis, Anopheles albitarsis, Anopheles darlingi, Culex quinquefasciatus, Culex nigripalpus, Haemagogus leucocelaenus e Psorophora ferox. Destaca-se a redução do número de espécies no período pós enchimento, juntamente com a recolonização do nicho por novas espécies ou espécies antes raras, como exemplificado pelo surgimento do An. darlingi, e ascensão do An. albitarsis, espécies consideradas vetores primário e secundário da malária, no Brasil, respectivamente. Como conclusão, depreende-se que o lago formado pela represa de Ourinhos alterou a dinâmica de culicídeos do local, fato que pode representar menor contato desses hematófagos com a população no entorno do lago recém formado / If the hydroelectric power plants supply the needs of the country, they are also responsible for the proliferation of diseases whose pathogens are transferred, in most of time, by mosquitoes that using the flooded areas such as breeding. It can be observed this scenario in the HPP of Ourinhos, which is located on the Paranapanema river between the cities of Ourinhos, SP, and Jacarezinho, PR, where three stations were established to collect used for assessing the diversity of populations in the pre and post flooding of the reservoir from the data collected described the changes occurring in the population of Culicidae of Ourinhos HPP, before the impacts of flooding and it was estimated richness, dominance, and diversity, standardized index of abundance of species and similarity. Where to catch the adult was used the Shannons trap and vacuum, and for the immature forms \"entomological ladle\" in collections of stagnant water. Among the species of epidemiological importance have collected and identified: Aedes albopictus, Aedes scapularis, Anopheles albitarsis s.l, Anopheles darlingi, Culex quinquefasciatus, Culex nigripalpus, Haemagogus leucocelaenus and Psorophora ferox. It is reducing the number of species in the period after filling, together with the recolonization of the niche for new species or rare species before, as exemplified by the emergence of Anopheles(Nys.) darlingi and Anopheles albitarsis s.l rise of species, as primary and secondary vectors malaria in Brazil, respectively. In conclusion, it appears that the lake formed by the dam of Ourinhos changed the diversity of the mosquitoes in site, which may represent less contact with the blood of people around the newly formed lake
48

The U.S. small hydropower industry : opportunities for development and barriers to success

Wymond, David Tyler 13 July 2011 (has links)
With many states recently enacting either renewable energy mandates or goals,the small hydropower industry has a unique opportunity to supply a growing portion of U.S. electricity supply. But the procedure to obtain a license for project development is unwieldy, increasingly wrought with regulatory hurdles at both the state and Federal levels. Government incentives exist that promote the development of small hydropower,but are insufficient to overcome the regulatory barriers faced by the industry. Although it is possible for small hydropower to supply a growing share of energy production in the U.S., it is unlikely that the full potential will be realized without substantial changes to the renewable energy regulatory system. This study describes the current state of the regulatory system governing the development of small hydropower facilities in the United States. A basic overview of hydroelectric technology is discussed, followed by a detailed description of the process through which a project developer must apply for a Federal license to construct and operate a hydropower project. The current state of the U.S. small hydropower industry is examined, considering the potential opportunity for the industry to supply a growing share of the U.S. electricity supply. This analysis is supplemented by a discussion of the costs of project construction and an investigation into the regulatory barriers to project development. / text
49

Influences de modifications de surface sur le climat : région de la Baie de James

Perrier, Michel Germain. January 1975 (has links)
No description available.
50

A large scale optimization procedure for the conjunctive use of surface and ground water resources

Coşkunoğlu, Osman 08 1900 (has links)
No description available.

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