A dissertação trata da aplicação de técnicas de programação não linear para otimização da operação de sistemas hidroenergéticos. Foi analisado o desempenho de diferentes funções objetivo para a otimização energética, assim como de regras para deplecionamento de sistemas hidroenergéticos com configurações em paralelo e em série. Neste caso, foi utilizado um sistema hipotético de reservatórios para permitir maior adequação do sistema aos conceitos que foram testados. O sistema Paranapanema foi escolhido como caso de estudo. Para esta bacia discutem-se aspectos ligados às séries hidrológicas, que constituem o principal dado de entrada do processo de otimização. A aplicação ao sistema Paranapanema foi efetuada com otimização de períodos de até 20 anos. Foram definidas novas regras baseadas na observação dos resultados da otimização de longo período e também apresentados padrões de variação da geração e dos volumes dos reservatórios. Foram feitas comparações com a operação real observada. Apresentou-se uma aplicação à operação de tempo real, que define políticas de operação para curto prazo. Essa aplicação tem horizonte de 12 meses, partindo-se do mês atual e considerando cenários futuros baseados em prognósticos climáticos. Os resultados mostram que a partir das regras definidas é possível ter um entendimento do processo de otimização. Os padrões de variação da geração e dos volumes auxiliam na elaboração de políticas de operação. Dessa forma se tem uma visão abrangente da otimização de um sistema hidroenergético considerando os resultados da otimização dentro de um ciclo sazonal conjuntamente com as implicações da otimização de longo período. / An application analysis of nonlinear programming is developed for hydropower systems optimization. The Paranapanema system is chosen like case study and treats aspects tied to hydrological series, that constitute the main input of optimization process. Different objective functions performance are analyzed for the hydropower optimization. It analyzes rules for emptying of hydropower reservoirs with configurations in parallel and in series. In this case a hypothetical system is used to allow larger system adaptation to the concepts that are tested. An application to the Paranapanema system is made, working with periods optimization of up to 20 years. New rules are defined based on the observation of the results of long period optimization. Also variation standards of power generation and reservoirs volumes are introduced. Comparisons with the observed operation are made. An application to real time operation is made, that defines operation policies for short term. This application has horizon of 12 months, departing of the current month and considering future scenarios based on climate prediction. The results show that is possible to have an optimization process understanding from the defined rules. The generation and volumes variation standards assist in the operation policies elaboration. Thus it has a general vision of hydropower system optimization, considering the results of optimization inside seasonal cycle jointly with the optimization long period implications.

Além do discurso de desenvolvimento nacional associado à construção de usinas hidrelétricas, tem sido destacado nos planos do setor de energia, nos discursos do governo e nos documentos técnicos relativos ao processo de avaliação de impacto um potencial de indução do desenvolvimento local associado à instalação de usinas hidrelétricas no território. Este suposto desenvolvimento local é favorecido por alguns aspectos relativos à construção das hidrelétricas, como o potencial de dinamização econômica das regiões onde os projetos são instalados e o aumento das receitas dos municípios diretamente afetados, uma vez que estes passam a receber recursos financeiros provenientes diretamente da geração de energia elétrica. Neste sentido, estes fatores têm sido utilizados para justificar uma série de novos projetos, planejados e em implantação expressos nos Planos Decenais de Expansão de Energia. Devido à falta de evidências empíricas que atestem esta relação entre existência de usinas hidrelétricas no território e o desenvolvimento local, o objetivo desta tese é o de verificar se municípios diretamente afetados por hidrelétricas têm desempenho de desenvolvimento melhor do que municípios indiretamente afetados, pertencentes a uma mesma região. Neste sentido, os desempenhos de desenvolvimento de três grupos de municípios, sob influência das hidrelétricas de Machadinho, Itá, Barra Grande e Campos Novos, foram comparados a partir do teste estatístico de Mann-Whitney. Buscou-se avaliar também a correlação entre a quantidade de recursos financeiros recebidos pelos municípios diretamente afetados com o desempenho de desenvolvimento, relativo à variação de um conjunto de indicadores de desenvolvimento local no tempo. Apesar de um dos grupos ter se destacado em relação à dimensão econômica, para a maioria dos indicadores utilizados não foi possível destacar um melhor desempenho por parte dos grupos diretamente afetados. Ressalta-se que um dos grupos de municípios diretamente afetados apresentou pior desempenho em relação à produção industrial e à concentração de renda. Encontrou-se correlação positiva entre a quantidade de recursos recebidos e a produção relativa ao setor de serviços e ao IDH renda. Porém, encontrou-se uma correlação negativa para o indicador alfabetismo. Concluiu-se, para a região estudada para o período de 2000 a 2010 que as UHEs e seus fatores associados, como os recursos financeiros, não têm servido à promoção dos fatores locais de desenvolvimento. Assim, sugere-se uma discussão a partir da formação potencial de um enclave associado a esta atividade. / In addition to the national development discourse associated to the construction of hydroelectric power plants, it has been highlighted the potential of this kind of projects in promoting local development, this has been appearing in the plans for the energy sector, in the speeches of the government and in technical documents related to the environmental impact assessment process. This supposed local development is supported by some aspects concerning the construction of dams, such as the potential for economic dynamism of the regions where the projects are installed and the income increase of the directly affected municipalities, since they start to receive financial resources from the electricity generation. In this sense, these factors have been used to justify a number of new projects, planned and under construction, expressed in the Decennial Plan for Energy Expansion. Due to the lack of empirical evidence attesting this relation between existence of hydropower plants in the territory and its local development, the aim of this thesis is to determine whether municipalities directly affected by hydropower development have e better development performance than those municipalities that are indirectly affected but belong to a same region. In this sense, the development performances of three groups of municipalities, under the influence of Machadinho, Ita, Barra Grande and Campos Novos hydro powers, were compared from the statistical test of Mann-Whitney. Attempt was also made to evaluate the correlation between the amount of funds received by the municipalities directly affected and the variation of a set of indicators of local development. Although one of the groups have been highlighted in relation to the economic dimension, for most of the indicators has not been possible to highlight better performances by neither of the groups. It is noteworthy that one of the groups directly affected showed worse performance in relation to industrial production and the concentration of income. There was a positive correlation between the amount of funds received and the production concerning the service sector and the HDI income. However, it was found a negative correlation for the literacy indicator. It was concluded, to study case for the 2000-2010 periods that the HPPs and associated factors such as financial resources, have not served to the promotion of local development factors. Thus, it is suggest a debate over the potential to enclave\'s establishment due to this sort of activity.

This dissertation explores a core tension in contemporary hydropower governance between two competing views: hydropower as a machine and as a geography. Policymakers rely on economic and engineering optimization models to plan energy system adaptations to climate change. The developers of those models tend to narrowly view the hydropower system as a combination of infrastructure and operations constraints that are knowable and replicable. They rely on quantifications of values to produce “optimal” outcomes given constraints. This is hydropower the machine. But more holistically, hydropower is a geography. Hydropower transforms waterways, implicating competing interests and values in limited resources: surface water and the landscapes it traverses. The first paper of this dissertation, published in Natural Resources Journal, takes an institutional economics lens to introduce the tension between the two views. Through an examination of two optimization models and an overview of hydropower law in California, that article argues that otherwise well-regarded and well-funded models of the hydropower system nonetheless fall short of informing policy because those models rely on an incomplete concept of governance. A partial resolution of the tension may be possible. The history of the development of one hydropower optimization model confirms the bulk of literature on co-production and collaborative science research. The participation of hydropower practitioners into the research and modelling process influenced the parameters and inputs to the model. And in doing so, the collaborative research produced a product that was credible, legitimate, and salient. As such, despite the mechanistic view of hydropower prevalent in the optimization model, the end result fit better within the immediate political context as communicated by the oversight committee. Additionally, the combination of formal rules for collaboration and the simultaneous creation of informal knowledge networks helped to bolster acceptability of the product. Even after formal processes and funding ended, the knowledge networks continued and were able to facilitate the eventual implementation of the model as a decision support tool. Yet, a closer look at just one aspect of hydropower governance—litigation in federal courts—reinforces the divide between hydropower the machine and the geography. A review of the past century of federal hydropower caselaw offers a window in to the multiple and evolving ways that water and energy law influence one another. Ultimately that history embraces variation as a core characteristic of hydropower governance, a condition which is at odds with the practical needs of modelling.

Variations in the electricity consumption and production connected to the power system have to be balanced by active control. Hydropower is the most important balancing resource in the Nordic system, and will become even more important as the share of variable renewable energy sources increases. This thesis concerns balancing of active power, especially the real-time balancing called frequency control. The thesis starts in a description of the situation today, setting up models for the behaviour of hydropower units and the power system relevant to frequency control, and comparing the models with experiments on several hydropower units and on the response of the Nordic grid. It is found that backlash in the regulating mechanisms in hydropower units have a strong impact on the quality of the delivered frequency control. Then, an analysis of what can be done right now to improve frequency control and decrease its costs is made, discussing governor tuning, filters and strategies for allocation of frequency control reserves. The results show that grid frequency quality could be improved considerably by retuning of hydropower governors. However, clear technical requirements and incentives for good frequency control performance are needed. The last part of the thesis concerns the impact from increased electricity production from variable renewable energy sources. The induced balancing need in terms of energy storage volume and balancing power is quantified, and it is found that with large shares of wind power in the system, the energy storage need over the intra-week time horizon is drastically increased. Reduced system inertia due to higher shares of inverter connected production is identified as a problem for the frequency control of the system. A new, linear synthetic inertia concept is suggested to replace the lost inertia and damping. It is shown that continuously active, linear synthetic inertia can improve the frequency quality in normal operation and decrease wear and tear of hydropower units delivering frequency control.

Hydropower plants contains a lot of vital electrical power technology such as generators and transformers. To prevent damage to this equipment due to overvoltage, they are often protected by surge arrester and in some cases also by surge capacitors. The design and dimension of these components vary between different sites and regions and are often done using a template without considering the actual conditions of the site. In this thesis Simulink and Simscape Power System are used to study the case when a hydropower station is exposed to overvoltage. One of Fortum’s hydropower stations is simulated when being exposed to lightning and switching overvoltage to see how the existing overvoltage protection handles this stress. The results show that the surge arresters mounted in front of the generator managed to keep it safe for all overvoltage scenarios it is exposed to. They also shows that the surge capacitors mounted in front of the generator reduces the gradient of the overvoltage surge. However, as the surge arresters already keeps the overvoltage at safe levels, there is no need of reducing the overvoltage gradient and the surge capacitors becomes excessive in this particular hydropower plant. / Vattenkraftverk innehåller många vitala komponenter så som generatorer och transformatorer. För att skydda dessa oftast väldigt dyra komponenter mot överspänningar, används ventilavledare och ibland också överspänningskondensatorer. Utformning och dimensionering av skydden varierar mellan olika anläggningar och regioner. Dimensioneringen av skydden görs ofta schablonmässigt, utan någon väsentlig anpassning till de faktiska förhållandena. I detta examensarbete används simuleringsverktyget Simulink tillsammans med tillägget Simscape Power Systems för att simulera vad som händer när ett vattenkraftverk utsätts för olika överspänningar. Ett av Fortums vattenkraftverk studeras när det utsätts för blixt- och kopplingsöverspänningar för att se vad ventilavledarna samt överspänningskondensatorerna i denna anläggning fyller för funktion. Resultaten visar att ventilavledarna monterade framför generatorn klarar av att hantera alla överspänningar de utsätt för under simuleringarna. Resultaten visade också att överspänningskondensatorerna monterade framför generatorn sänker spänningsgradienten, men eftersom ventilavledarna redan håller spänningen på en säker nivå blir överspänningskondensatorerna överflödiga i denna station.

Across the world, it is becoming increasingly obvious that we must change the way we live as human beings. Our population is over seven billion, and the natural world simply cannot sustain this large of a population unless we learn to live within its means. Buildings, the structures that house us and provide us with shelter every day, are responsible for nearly half of the energy consumption across the United States (eai.gov, 2008). As cities continue to grow and available land diminishes, buildings will only get taller and consume even more energy. This energy requires vast amounts of water, so as our population grows, we are using more energy and more water, two of the most critical components of human prosperity. Renewable and sustainable energy production is now more of a reality than ever, especially as people become aware of the impending shortage of natural resources.I propose to offer a modified renewable energy source in a new environment. The use of hydropower turbines for renewable energy generation is something common to many places across the globe, but the use of hydropower turbines in a building is not. In this paper I propose a system that utilizes greywater from high-rise residential buildings to create energy with hydropower turbines at the base of the building. Calculations show the system can produce energy, but improvements and changes need to be considered for this to be a commercially viable renewable energy source.

Small scale hydropower is one of the most cost-effective energy technologies to be considered for electrification in developing countries. The technology is very robust and mature so systems can last up to 50 years with little maintenance. Moreover, it has low environmental impacts and can have a significant benefit if implemented in rural areas for electricity production, either in on or off grid applications.The thesis reviews several small scale hydropower projects, in order to identify potential risks and propose guidelines to help future implementation of this technology in a better way than the one currently done. An on-going project was taken as a case study to identify different elements that have to be present in the planning and future development of small scale hydro projects in developing countries. Technical, managerial, socio-economical and environmental aspects around the project were analyzed within a sustainability framework.

Hydropower production has advantages but also negative ecological consequences. Thisstudy analyzes the degree of flow variations downstream Viforsen's power plant to investigate how well the regulated flow is re-regulated towards a more natural flow pattern. The studyalso examine effects of the regulation on valuable salmon habitats in the section from Viforsen's power plant down to the sea and whether there is a downstream gradient in the presence of different fish species. Data on water level changes was obtained by installingthree pressure loggers in a gradient downstream of the Viforsen power plant. Collection of hourly flow-data in Viforsen and Vindelälven have been part of the data in the survey. The presence of different species of fish was determined by examination of the Swedish electrofishing registry. Results showed a strong correlation between flow and water level at all three sites in Ljungan and there is no ecologically significant dampening of water level fluctuations downstream Viforsen. The current requirement for a minimum discharge of 30 m3/s is too low as important salmon habitats risk being drained. The strong correlation between water levels and flow that this study shows make it possible to map in more detail the risks of valuable salmon habitats drying up. The results also showed that typically marine species” of fish are much more common in Viforsen than in Vindelälven. This study emphasizes that ecologically sustainable flows are complex and relevant field investigations at each watercourse are necessary when reconsidering and designing the new environmental conditions.

京都大学 / 0048 / 新制・論文博士 / 博士(地球環境学) / 乙第12901号 / 論地環博第11号 / 新制||地環||26(附属図書館) / 31655 / (主査)教授 渡邉 紹裕, 教授 宇佐美 誠, 准教授 小林 広英 / 学位規則第4条第2項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

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