Insufficient Brazilian production of electricity in recent years leads to essential investments in the sector, increasing the possibility of using alternative energy. BNDES participation becomes necessary, as the only Brazilian bank to finance infrastructure and to offer specific lines for the segment of renewable energy. The aim of this study was to analyze whether the lines of credit offered by the BNDES by December 2013 were adequate for the financing of wind power generation projects. In this dissertation, a survey of credit lines from BNDES is presented for wind energy, considering the context of the historical performance of the bank and the main aspects of wind energy in Brazil by the year 2013. The presented research is qualitative, bibliographic and documentary. The documents analyzed are only those of public and unrestricted access. Due to the availability of data and consolidated reports in official media, the survey period was restricted until December 2013. The results showed that the BNDES did not make available lines of specific funding for wind energy production. However, the lines oriented in a comprehensive way, the production of renewable energies were appropriate to wind projects. Despite the availability of financing lines, there are bureaucratic barriers that hinder the use of these resources. / A insuficiente produção brasileira de energia elétrica nos últimos anos leva a imprescindíveis investimentos no setor, ampliando a possibilidade de utilização das energias alternativas. A participação do BNDES torna-se necessária, por ser o único banco brasileiro a financiar a infraestrutura e a oferecer linhas específicas para o segmento das energias renováveis. O objetivo desse estudo foi analisar se as linhas de crédito oferecidas pelo BNDES até dezembro de 2013 foram adequadas ao financiamento de projetos de geração de energia eólica. Nesta dissertação, é apresentado um levantamento das linhas de financiamento do BNDES para a energia eólica, considerando o contexto da atuação histórica do banco e os principais aspectos da energia eólica no Brasil até o ano de 2013. A pesquisa apresentada é de natureza qualitativa, bibliográfica e documental. Os documentos analisados são somente àqueles de acesso público e irrestrito. Devido à disponibilidade de dados e relatórios consolidados, em meios oficiais, o período da pesquisa foi restrito até dezembro de 2013. Os resultados obtidos apontaram que o BNDES não disponibilizava linhas de financiamentos específicas para a produção eólica de energia. Entretanto, as linhas voltadas, de maneira abrangente, à produção de energias renováveis foram adequadas aos projetos eólicos. Apesar da disponibilidade de linhas de financiamento, há entraves burocráticos que dificultam o uso desses recursos.

The objective of this thesis is to assess the optimal power production and flight trajectories of crosswind, ground-generation or pumping-mode airborne wind energy systems (AWES), subject to realistic onshore and offshore, mesoscale-modeled wind data as well as LiDAR wind resource assessment. The investigation ranges from small scale AWES with an aircraft wing area of 10 m^2 to utility scale systems of 150 m^2. In depth knowledge of the wind resource is the basis for the development and deployment of any wind energy generator. Design and investment choices are made based on this information, which determine instantaneous power, annual energy production and cost of electricity. In the case of AWES, many preliminary and current analyses of AWES rely on oversimplified analytical or coarsely resolved wind models, which can not represent the complex wind regime within the lower-troposphere. Furthermore, commonly used, simplified steady state models do not accurately predict AWES power production, which is intrinsically linked to the aircraft's flight dynamics, as the AWES never reaches a steady state over the course of a power cycle. Therefore, leading to false assumption and unrealistic predictions. In this work, we try to expand our knowledge of the wind resource at altitudes beyond the commonly investigated lowest hundreds of meters. The so derived horizontal wind velocity profiles are then implemented in to an optimal control framework to compute power-optimal, dynamically feasible flight trajectories that satisfy operation constraints and structural system limitations. The so derived trajectories describe an ideal, or at least a local optimum, and not necessarily realistic solution. It is unlikely that such power generation can be reached in practice, given that disturbances, model assumptions, misalignment with the wind direction, control limitations and estimation errors, will reduce actual performance. We first analyze wind light detection and ranging (LiDAR) measurements at a potential onshore AWES deployment site in northern Germany. To complement these measurements we generate and analyze onshore and offshore, mesoscale weather research and forecasting (WRF) simulations. Using observation nudging, we assimilate onshore LiDAR measurements into the WRF model, to improve wind resource assessment. We implement representative onshore and offshore wind velocity profiles into the awebox optimization framework, a Python toolbox for modelling and optimal control of AWES, to derive power-optimal trajectories and estimate AWES power curves. Based on a simplified scaling law, we explore the design space and set mass targets for small to utility-scale, ground-generation, crosswind AWESs. / Graduate

Nowadays, the climate change issue is becoming more and more actual in our society. Increase of the average temperature on Earth in a couple of degrees could have catastrophic consequences. One of the possible solutions seems to be renewable energy sources as photovoltaics, biomass of water and wind energy. This thesis deals with the aerodynamics problems of wind energy source. Wind turbines transform kinetic energy of wind to mechanical power. The efficiency is physically limited to 59,26 %, but in reality, it is getting around 45 %. This is caused by three biggest losses inducted in wind turbines as wake losses, losses due to finite number of blades and drag losses. Based on analytical relationships and including these three losses the aerodynamics blade design is conducted. Later, the numerical simulations show higher values of drag and lower values of lift force on airfoil compared to analytical calculation. In fact, percentage deviations are acceptable and to conclude, the numerical analysis was able to relatively accurately simulate force action of free stream velocity on the blade.

This master thesis deals with problematic wind power plants. There are described advantages and disadvantages of wind power plants and their environmental impacts. Thesis include chosen locality for wind power plant, chosen fitting types of turbines and calculation which choosing turbine for chosen locality. There are accomplished parametric studies of main parameters. From this study is chosen best fitting model of wind turbine. In the end are adduced statistics from Czech Republic, Europe and world.

Orientador: Antonio Roberto Balbo / Resumo: A produção de energia eólica tem se destacado no Brasil e mostrado grande importância na questão ambiental, pois auxilia na redução da emissão dos gases poluentes na atmosfera, provenientes de outras fontes de energia. Neste trabalho é proposta uma modelagem matemática de otimização multiobjetivo a qual explora a produção de energia eólica em um problema de despacho econômico e ambiental termo-eólico. O principal objetivo é mostrar que uma metodologia determinística envolvendo os métodos de otimização multiobjetivo de restrições canalizadas progressivas e de técnicas de programação por metas ponderadas, em conjunto com o método de pontos interiores, é eficiente à resolução deste problema. É proposta uma nova técnica, a qual é uma combinação entre os métodos de otimização multiobjetivo citados. As soluções dos subproblemas gerados por estes métodos serão determinadas através de pacotes computacionais, onde são apresentados resultados de casos distintos de produção de energia, mostrando a insuficiência da energia eólica nos custos operacionais da geração e no impacto ambiental / Abstract: The production of wind energy has stood out in Brazil and has shown great importance in the environmental issue, as it assists to reduce of polluting gases in the atmosphere arising out of other sources of energy. In this work a mathematical modeling of optimization multiobjective is proposed, which explores the wind energy production in a thermal-wind environmental and economic dispatch problem. The main objective is to show that a deterministic methodology involving the multiobjective optimization methods, progressive bounded constraints and weighted goal programming techniques, together with an interior point method, is e cient to solve this problem. A new technique is proposed, which is a combination of the mentioned multiobjective optimization methods. The solutions of the generated subproblems by these methods will be determined through of computational package and the results of distinct cases of energy production will be presented, showing the in uence of the wind power on the generation and on the environmental impact. / Doutor

Wind farm layout optimization is a multidisciplinary undertaking, requiring students and researchers to integrate many skillsets in order to optimize turbine placement. There is currently a lack of useful benchmarking exercises for participants in the field to compare the efficacy of their methods. This work details the construction and completion of a set of four case studies meant to satisfy this need, with the hope of providing some insight into useful layout optimization approaches. These case studies are intended to also serve as instructive introductory exercises with which newcomers researching wind energy may incrementally practice and increase their abilities.The first two case studies were released globally and attracted participants from around the world who attempted the optimization problems. A detailed analysis of their results is presented herein.The second two case studies are currently being worked on by researchers in the field, with initial feed back regarding the formulations also included.

The Wind Turbine industry continues to drive towards high market penetrationand profitability. In order to keep Wind Turbines in field for as long as possiblecomputational analysis tools are required. The open source tool QBlade[38] softwarewas extended to now contain routines to analyse the structural properties of WindTurbine blades. This was achieved using 2D integration methods and a Tapered Euler-Bernoulli beam element in order to find the mode shapes and 2D sectional properties.This was a key step towards integrating the National Renewable Energy LaboratoriesFAST package[32] which has the ability to analyse Aeroelastic Responses. The QFEMmodule performed well for the test cases including: hollow isotropic blade, rotatingbeam and tapered beam. Some improvements can be made to the torsion estimationof the 2D sections but this has no effect on the mode shapes required for the FASTsimulations.

Wind tunnel studies of the wake behind a model wind turbine have been made in order to get a better understanding of wake development as well as the possibility to predict the power output from downstream turbines working in the wake of an upstream one. Both two-component hot-wire anemometry as well as particle image velocimetry (PIV) have been used to map the flow field. All three velocity components were measured both for the turbine rotor normal to the oncoming flow as well as with the turbine inclined to the free stream direction (the yaw angle was varied from 0 to 30 degrees). The measurements showed, as expected, a wake rotation in the opposite direction to that of the turbine. A yawed turbine is found to clearly deflect the wake flow to the side showing the potential of controlling the wake position by yawing the turbine. The power output of a yawed turbine was found to vary nearly as the square of the cosine of the yaw angle. The possibility to use active wake control by yawing an upstream turbine was evaluated and was shown to have a potential to increase the power output significantly for certain configurations. An unexpected feature of the flow was that spectra from the time signals showed the appearance of a low frequency fluctuation both in the wake and in the flow outside. This fluctuation was found both with and without free stream turbulence and also with a yawed turbine. The non-dimensional frequency (Strouhal number) was independent of the free-stream velocity and turbulence level but increases with the yaw angle. However the low frequency fluctuations were only observed when the tip speed ratio (or equivalently the drag coefficient) was high. This is in agreement with the idea that the turbine shed structures as a bluff body. It is hypothesized that the observed meandering of wakes in field measurements is due to this shedding.

Wind farm layout optimization is a multidisciplinary undertaking, requiring students and researchers to integrate many skillsets in order to optimize turbine placement. There is currently a lack of useful benchmarking exercises for participants in the field to compare the efficacy of their methods. This work details the construction and completion of a set of four case studies meant to satisfy this need, with the hope of providing some insight into useful layout optimization approaches. These case studies are intended to also serve as instructive introductory exercises with which newcomers researching wind energy may incrementally practice and increase their abilities.The first two case studies were released globally and attracted participants from around the world who attempted the optimization problems. A detailed analysis of their results is presented herein.The second two case studies are currently being worked on by researchers in the field, with initial feed back regarding the formulations also included.

The electricity sector is a major source of carbon dioxide emission that contributes to the global climate change. Over the past decade wind energy has steadily emerged as a potential source for low carbon energy source which are grown through time. As wind power generation increases around the world, there is increasing interest in adding intermittent power to the electricity grid and to design an off-grid wind energy system. The goal of the current thesis is to investigate techno-economically viable wind energy system that supplies electricity and Heat for a given residential community in Ethiopia. To ease the optimization process, HOMER software is used to identify the potential wind area and optimize cost effective wind energy system.