The passage efficiency of downstream migrating brown trout (Salmo trutta) smolts past two hydropower plants in the River Emån, southeastern Sweden, was evaluated by telemetry. From 26 April to 17 May 2005, 40 wild brown trout smolts were radio-tagged, and their positions were recorded daily until 14 June. Approximately 45% of the individuals passed both power plants, and 15% made it to the sea, some 28 km downstream of the power plants. About 20% of the individuals ceased migrating, residing in a lotic habitat. Mortality due to predation was 33%, and the predation rate was higher in the power plant dams than it was downstream of the power plants. Turbine-induced mortality was greater in the upper power plant (40%) than in the lower one (13%). Fish that chose the alternative routes, through the gates, swam past the upper dam faster than fish that swam through the turbines. The results confirm previous work in the river, namely that measures need to be taken to improve passage efficiency past the power plants, particularly passage of the upper power plant. Such measures are of crucial importance if the nature-like bypass channels at the power plants in Finsjö are going to have any long-term effects on the brown trout population. / Passageeffektiviteten för nedströms vandrande havsöringssmolt (Salmo trutta) förbi två vattenkraftverk i Emån, i sydöstra Sverige, utvärderades med telemetri. Från 26 april till och med 17 maj 2005 märktes 40 vilda havsöringssmolt med radiosändare och de positionsbestämdes dagligen till och med 14 juni. Ungefär 45% av individerna passerade båda kraftverken, och 15% klarade sig till havet, cirka 28 km nedströms kraftverken. Omkring 20% av individerna avbröt vandringen och stannade i ett lotiskt habitat. Mortalitet på grund av predation uppgick till 33%, och predationshastigheten var högre i kraftverksdammarna än nedströms kraftverken. Den turbininducerade mortaliteten var högre i det övre kraftverket (40%) än i det nedre (13%). Det gick fortare att passera den övre kraftverksdammen för fisk som valde de alternativa rutterna, genom dammluckorna, jämfört med att passera genom turbinerna. Dessa resultat bekräftar tidigare studier i ån, nämligen att åtgärder krävs för att förbättra passageeffektiviteten förbi kraftverken, i synnerhet passagen av det övre kraftverket. Sådana åtgärder är av avgörande betydelse om de naturlika fiskvägarna vid kraftverken i Finsjö ska få några långsiktiga effekter på havsöringspopulationen.

Made available in DSpace on 2015-03-26T13:33:56Z (GMT). No. of bitstreams: 1 texto completo.pdf: 7608406 bytes, checksum: 8ace6c23dc0baa460565d6d8e40d67bd (MD5) Previous issue date: 2013-07-05 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The central aim of this thesis was to analyze the process of readjustment of the population of São Sebastião do Soberbo, located in the municipality of Santa Cruz do Escalvado on the basin of Upper river Doce/Minas Gerais, affected by the Candonga Hidroelectric Dam (UHE Candonga) and shifted to the resettlement of Nova Soberbo in mid-2003 and early 2004. It was done with emphasis on the limits, the possibilities and the capabilities of the residents in rebuilding their livelihoods about on the event of displacement and resettlement for the new spatiality. Therefore, the analysis presented was based on a case study in 2012 through archival research, participant observation, a structured questionnaire, a method of oral history and photographic resources. In this context, the study addressed the resettled population in three distinct time frames, namely the arrival of the UHE Candonga to São Sebastião do Soberbo, the process of construction and inauguration of the dam with its social, economic and cultural impacts on the order of everyday life and the social deployments of this event over 9 years in the resettlement. The theoretical axis guided itself with a view towards the interpretation of the phenomenon of hydroelectricity as a social event, which changes the daily lives of those who for the first time are faced with large infrastructure projects arising from the promotion of economic and social developments within society. Furthermore, the theory of the forced displacement and resettlement was tested, advocating various changes and breaks in the trajectory of population groups that undergo changes in their traditional ways of life. In general, resettlements are pointed as promoter of social change that implies the need to restructure the individual, family and community life. This restructuring was analyzed from the perspective of the approach towards the livelihoods and on the theory of human agency that highlight the ability of social actors to process experiences and incurring actions and strategies in an attempt to access the tangible and intangible resources in reinventing the ways of survival. The social deployments that occurred under the conditions offered and structured by the entrepreneur, mainly on the basis of the relationships established between the Consórcio Candonga and the residents of resettlement, implied in the constitution of the category dam-affected people. This finding also suggested a more detailed analysis of this social condition whose existence was triggered by the construction of the dam. Reflections on the case study showed definite changes in the forms of social production and reproduction of the residents; and the resettlement, as a possibility for the reconstruction of everyday life, presented itself as a space that marks impossibilities and difficulties in the reestablishment of the previous social relations and living activities in the fabric of new social references erected in the action and intervention of the Cansórcio Candonga. The reflections also showed the many subjective and emotional damages as a result of the feeling of uprootment caused by the impact of the dam, of the limitations of survival in resettlement and of the failure of the entrepreneur to mitigate and compensate for the various losses occurring in the shift from one place to another. And the resettles, when experience this process, forge new elements in their individual and social condition that constitute themselves as dam- affected people who incurring in the struggle for the recognition of their denied rights. Thus, the implementation of the dam reverberated in a profound process of social transformation for those who still live under the impact of the displacement/resettlement and comes into difficulties in appropriation of the new material and immaterial conditions to ensure social readjustment. / O objetivo central desta dissertação foi analisar o processo de readequação da população de São Sebastião do Soberbo, que vive no município de Santa Cruz do Escalvado, na bacia do Alto do rio Doce/Minas Gerais, atingida pela Usina Hidrelétrica Candonga (UHE Candonga) e que foi deslocada para o reassentamento de Nova Soberbo em meados de 2003 e início de 2004. Para tanto, buscou-se enfatizar os limites, as possibilidades e as capacidades dos moradores em recriar seus meios de vida frente ao acontecimento do deslocamento e do reassentamento para o novo espaço. A análise apresentada baseou-se em um estudo de caso realizado em 2012 com a utilização de pesquisa documental, da observação participante, da aplicação de questionários incluindo questões abertas, da história oral, bem como recursos fotográficos. Neste contexto, a pesquisa abordou os reassentados com base em três temporalidades distintas, a saber, a chegada da UHE Candonga a São Sebastião do Soberbo, o processo de construção e de inauguração da Usina com seus impactos sociais, econômicos e culturais na ordem da vida cotidiana e os desdobramentos sociais deste acontecimento ao longo de 9 anos no reassentamento. O eixo teórico considerou a interpretação do fenômeno da construção da barragem enquanto acontecimento social que altera o cotidiano daqueles que, pela primeira vez, se deparam com grandes empreendimentos de infraestrutura que se apresentam como promotores do desenvolvimento econômico e social da sociedade. Utilizou- se também de diferentes abordagens sobre deslocamentos e reassentamentos involuntários que preconizam diversas mudanças e rupturas na trajetória de contingentes populacionais que sofrem alterações nos seus modos de vida tradicionais. Os reassentamentos, em geral, implicam na necessidade de reestruturação da vida individual, familiar e coletiva. Reestruturação esta aqui analisada sob a ótica da abordagem dos meios de vida e sob a teoria da agência humana que destacam a capacidade dos atores sociais de processarem experiências e incorrerem em ações e estratégias na tentativa de acesso a recursos tangíveis e intangíveis na reinvenção das formas de sobrevivência. Os desdobramentos sociais decorrentes das condições oferecidas e estruturadas pelo empreendedor, principalmente, em função das relações estabelecidas com o Consórcio Candonga e a vivência no reassentamento, implicaram na constituição da categoria social atingido por barragem . Esta constatação sugeriu também uma análise mais detalhada desta condição social cuja existência foi desencadeada pela construção da barragem. As reflexões obtidas, a partir deste estudo de caso, apontaram algumas alterações definitivas nas formas de produção e reprodução social dos moradores, e o reassentamento, enquanto possibilidade de reconstrução do cotidiano, apresentou-se como um espaço que marca impossibilidades e dificuldades de reestabelecimentos das anteriores relações sociais e atividades de sustento na tessitura de novas referências sociais erigidas sob a atuação e a intervenção do Consórcio Candonga. Demonstraram, ainda, diversos danos subjetivos e emocionais ocasionados pela sensação de desenraizamento provocados pelo impacto da barragem, pelas limitações de sobrevivência no reassentamento e pelas falhas do empreendedor em mitigar e compensar as diversas perdas ocorridas com a mudança de um lugar a outro. E os reassentados, ao vivenciarem este processo, forjam novos elementos no âmbito da sua condição individual e social constituindo- se em atingidos por barragem que incorrem na luta por reconhecimento de seus direitos denegados. Assim, a implantação da barragem repercutiu em um processo profundo de transformação social para aqueles que ainda vivem sob o impacto do deslocamento/reassentamento e vêm se deparando com dificuldades na apropriação das novas condições materiais e imateriais na garantia da reprodução social.

The objective of this diploma study is to develop and secure production of gear turbine with very low specific speed in comparison with conventional turbines. The first part of the work deals with already performed research of similar hydrostatic turbines. It is followed by construction design, including complete drawing documentation. The production of the prototype is secured by an external company. Finally, an experimental measurement of the characteristics of the designed turbine is performed in the laboratories of Fluid Engineering.

The aim of the present master’s thesis is to explore the feasibility of small hydropower plant for cur-rent hydro energetic potential of the weir on Ohře river, located in the city of Terezín in Ústecký re-gion, Czech Republic. The target of the thesis itself was to design minimally two variants of constructional and technological part. Due to requirements related to maintaining of all functions of the weir construction was decided to design small hydropower plant completely under the water surface, with flap mounted to the roof of the hydropower plant. Part of the thesis was also an economical assessment of designed hydropower project.

This thesis deals with the design of water turbine enabling optimal utilization of hydro-energetic potential of given location (barrage on Úpa river) chosen by ČEZ a.s. company. Moreover, the option of multi-unit layout is discussed. Because of the low-head profile of given location, the technology of swirl turbine in siphon configuration was chosen. Technology of swirl turbine presents new modification of Kaplan turbine with no need of guide vane. Swirl turbine is characterized by its high discharge and high speed. The main part of this thesis is focused on hydraulic design of the turbine.

This diploma thesis discusses the issue of finding type of water turbine for very low heads and low discharges, which could be operated as mobile micro hydropower plant in island mode. Thesis deals with summary of appropriate choices of water turbine for needs of micro hydropower plant. Essential part of diploma thesis deals with design of optimized waterwheel. Waterwheel was chosen because commercial high-speed turbines have low efficiency for low heads. Waterwheel was manufactured and measured in laboratories of Fluid engineering. Measurement output was discharge and efficiency characteristic of turbine. The price calculation was made after manufacture.

Hydropower plants with spillways exposed to high pressures because of large discharges can result in a dam failure which ultimately results in devastating consequences. Therefore properly designed and constructed spillways are important. In this project there is an interest in examining the pressure distribution on a guided wall, measuring the water level inside the spillway and examine the water flow characteristics. The main purpose was to numerically model the flow behaviors at two upper pool levels +29.82 m and +30.92 m in order to achieve a comparison between a numerical model and a physical model. A previous experiment was carried out at Vattenfall R&D in Älvkarleby where a physical model was built. The main purpose of that study was to find an optimal form of a guide wall for free weir flow. This study served as guidelines for what should be investigated in this project. The methodology of the project began with a development of an initial CAD model created by Vattenfall R&D. The CFD model could be constructed into a volume model containing also an upstream reservoir. Next, a mesh that could numerically calculate the flow behavior was created in order to enable execution of the calculations. Furthermore, a big part of the method was to adjust the settings in Fluent so that the numerical model could recreate the flow behaviors of the physical model tests. The results indicate that the numerical model is an accurate replica of the physical model. The deviation comprising the mass flow rate came as close as 0.6 % from the physical model for the lower upper pool level. Highest calculated pressure was positioned at the bottom of the guided wall for both upper pool levels, which the results conducted from the physical model also indicated. Furthermore, results regarding the water level at the guided wall confirmed same statement Vattenfall's examinations pointed out, that the roof placed at the guided wall is needed in order to avoid major splashing. The present project has shown great results regarding the flow characteristics, pressure distribution, and the water level at the guided wall. Therefore, it is considered trustworthy enough to be used as a tool for Vattenfall R&D in future studies comprising the targeted spillway.

In these days environmental issues are critical. Environmental concerns mainly rise from energy productions. Fortunately Ethiopia is trying to use renewable energy sources as a means for electrical power production and it is a great start for a long, tiresome green energy journey. The basic job to be done in green energy sectors is to maximize the capacity of renewable technologies to fulfil the best efficiency.  Intermittent nature of the energy production and their inefficiency to meet peak load demands are the basic problems in renewable energy sectors.   Ethiopia’s electrical power production is mainly dependent on hydropower; according to latest data from EEPCO hydro covers 88% of the total production. There are two major nature of this power plant; since the working medium is water it is mainly dependent on the nature of the seasons and secondly it rarely meets peak load demands. After the erection of the power plant the energy production is not time dependent; it can produce power continuously; but the consumption is time dependent which is defined as peak hours and off-peak hours. There is excess load in time of off-peak hours and scarcity in peak hours. So this work can help to maximize the capacity of the water for production by using technological advancements to produce lot of energy in almost full capacity throughout the year to full fill the need of our country. Tana Beles hydropower plant is the largest hydropower plant which starts to work in May, 2010 with an investment cost of $500 million and capacity of 460 MW. The project is planted in Amhara region using the water source of Lake Tana. To make this large and very necessary renewable energy resource sustainable using energy storage system will be vital. This study will figure out a pumped storage system for the hydropower plant for additional power production and for the sustainability of the water resource.    Pumped storage system is the only viable, large-scale resource that is being broadly utilized today for storing energy, and it offers the best option available for harnessing off-peak generation from renewable sources. The contributions of pumped storage hydro to our nation’s transmission grid by providing stability services, storage capacity needs, and expanding the green job market are considerable today.   The high energy demand of the pump will be considered to be covered using the excess electrical power production during night or weekends and if the resource is available using wind solar PV hybrid systems.   The author will try to assess the technology not only for other mini hydro power plants but also for irrigation and other purposes merely in Amhara region, Ethiopia. The feasibility of the system will be considered technically and economically for the hydropower plant.

Climate change has, in recent decades, warmed the climate and changed carbondynamics in land and water systems. For example, temperature and precipitation canchange carbon dynamics and cause largely unknown consequences. This researchuses data from a unique measuring station near Kattestrupeforsen, Jämtland, Sweden, in order to answer the question of how the pCO2 (ppm) concentration of the water in the local area reacts to changes in the factors of air/water temperature, solar irradiation, precipitation, turbidity, water level and water inflow into the area. This was analysed using a visual analysis of the peaks that occur in the pCO2 and a statistical regression analysis of peak pCO2 events and for each yearly quarter as well as for the identified peak events. Moreover, the limited amount of available turbidity data was visually analysed to comprehend how it correlates with the pCO2 values. The results indicate that the turbidity data available has no visible correlation, possibly due to a lack in data. Temperature data appeared to be responsible for some of the variation seen, although likely more as a conditional value. Irradiation and precipitation data gave inconsequent results and are not deemed likely to influence the peaks in pCO2 in the time scale analysed. Water level and streamflow showed the most stable and significant correlation of all parameters analysed, although they remained relatively inconsistentin their ability to explain pCO2 peaks seen. / <p>2024-03-06</p>

Ethiopia has been challenged by multidimensional poverty. However, it has the potential to minimize the threat through an integrated multipurpose development process. In this regard, hydropower has a significant role to reduce energy poverty and enhance the multipurpose use of natural resources efficiency. Hydropower is a source of clean, sustainable and renewable energy. It has a contribution to reducing carbon emission and maintaining environmental sustainability. In Ethiopia, it is the major source of electricity. The country is rich in natural resources, including water to produce energy, however, electricity supply is still uncertain. The data shows that the country has the potential to produce 50,000 MW energy from water resources. Yet, it exploited 3,822 MW in 2018, approximately 7.6 % of its potential. Moreover, the country faces issues with energy security. Additionally, water and food supply also face an uncertain future. In this case, the country has planned the growth and transformation plan I and II for 2015 and 2020 to increase the energy production to 10,000 MW and 17,000 MW energy respectively. Consequently, the government launched different multipurpose hydropower plant projects. This project focuses on the multipurpose use of the Grand Ethiopian Renaissance Dam, particularly for the sustainable energy-water-food-ecosystem service nexus at the national level. I applied the combination of methods such as the energy-water-food-ecosystem nexus, the SWOT analysis and the sustainability assessment as they are suitable for the complexity of such a project. Indeed, the GERD has benefits for the country in producing renewable and clean energy, generating income and increasing the water storage capacity at the national level. However, the project neglected the values of ecosystem services integration with the dam and its sectors. As a result, the dam affected the existed terrestrial biodiversity and ecosystem. Therefore, the GERD had not been the well-prepared plan that considers institutional cooperation and sectoral integration to use for multipurpose function and its sustainability. In these regards, unless the dam to take proper management of the project and natural resources, the hydropower plant would not have been generating sustainable energy production. / <p>The paper shows that how to use the reservoir hydropower plant for multipurpose, such as for energy, water, food, ecosystem services integration at local level</p>