Dissertations / Theses: 'Wind and solar generations'

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Watson, Eileen B. "Modeling Electrical Grid Resilience under Hurricane Wind Conditions with Increased Solar Photovoltaic and Wind Turbine Power Generation." Thesis, The George Washington University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10844532.

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The resource mix for the U.S. electrical power grid is undergoing rapid change with increased levels of solar photovoltaic (PV) and wind turbine electricity generating capacity. There are potential negative impacts to grid resilience resulting from hurricane damage to wind and solar power stations connected to the power transmission grid. Renewable power sources are exposed to the environment more so than traditional thermal power sources. To our knowledge, damage to power generating stations is not included in studies on hurricane damage to the electrical power grid in the literature. The lack of a hurricane wind damage prediction model for power stations will cause underestimation of predicted hurricane wind damage to the electrical grid with high percentages of total power generation capacity provided by solar photovoltaic and wind turbine power stations.

Modeling hurricane wind damage to the transmission grid and power stations can predict damage to electrical grid components including power stations, the resultant loss in power generation capacity, and restoration costs for the grid. This Praxis developed models for hurricane exposure, fragility curve-based damage to electrical transmission grid components and power generating stations, and restoration cost to predict resiliency factors including power generation capacity lost and the restoration cost for electrical transmission grid and power generation system damages. Synthetic grid data were used to model the Energy Reliability Council of Texas (ERCOT) electrical grid. A case study was developed based on Hurricane Harvey. This work is extended to evaluate the changes to resiliency as the percentage of renewable sources is increased from 2017 levels to levels corresponding to the National Renewable Energy Lab (NREL) Futures Study 2050 Texas scenarios for 50% and 80% renewable energy.

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Udayakanthi, Geetha. "Design of a Wind-Solar Hybrid Power Generation System in Sri Lanka." Thesis, KTH, Kraft- och värmeteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-179398.

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Energy is critical to the economic growth and social development of any country. Indigenous energy resources need to be developed to the optimum level to minimize dependence on imported fuels, subject to resolving economic, environmental and social constraints. This led to a boost in research and development as well as investment in renewable energy industry in search of ways to meet energy demand and to reduce dependency on fossil fuels. Wind and solar energy are becoming popular owing to abundance, availability and ease of harnessing for electrical power generation. This thesis focuses on an integrated hybrid renewable energy system consisting of wind and solar energy. Sri Lanka, a small island located south of the Indian subcontinent, has been blessed with renewable energy sources. According to the national energy policy a 10% share is targeted from NCRE (Non-Conventional Renewable Energy) sources by 2015 and 20% by 2020 out of total electricity generation in Sri Lanka. This thesis provides an insight into the energy scenario and present situation of renewable energy development in Sri Lanka. According to wind and solar potential maps of Sri Lanka which were developed by NREL in 2003, many parts of the country have potential to developed economic power generation. Through these maps locations were identified where both wind and solar potential is high. A detailed study was carried out in these locations with real time field data. The focal point of this thesis is to propose and evaluate a wind-solar hybrid power generation system for a selected location. Grid tied power generation systems make use of solar PV or wind turbines to produce electricity and supply the load by connecting to grid. In this study, HOMER (Hybrid Optimization Model for Electric Renewables) computer modeling software was used to model the power system, its physical behavior and its life cycle cost. The hybrid power system was designed for Hambantota District in Southern Sri Lanka. Through the simulation process, installation of 8 numbers of 850kW wind turbines and 1MW solar PV modules were identified as most economical to supply average of 3MW load connected to grid where the simple payback period of the system was 3.4 years.

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Luta, Doudou Nanitamo. "Modelling of hybrid solar wind integrated generation systems in an electrical distribution network." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1177.

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Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014
The research in this thesis deals with the application of Model Based Systems Engineering (MBSE) practices in the modelling of power systems. More particularly, we have presented the modelling hybrid photovoltaic wind integrated in an electrical distribution network using SysML (System Modelling Language) which is a modelling language in support of MBSE. MBSE refers to a formalised practice of systems development through the application of modelling principles, methods, languages and tools to the entire lifecycle of a system. Generally speaking, the modelling of power systems is performed using software such as Matlab Simulink, DigSilent, PowerWorld etc. These software programs allow modelling of a system considering only a specific viewpoint, depending on the objective that is to be assessed. The advantage of the SysML over the above mentioned modelling languages lies from the fact that SysML includes different viewpoints of a system. These views are known as the Four Pillars of SysML. Pillar One refers to the requirements of a system and includes all the functional and non-functional requirements. Pillar Two deals with the structure representation of a system by considering all its subsystems and their different connections. Pillar Three considers the behaviour of a system and includes its activities, sequences and different states. The last Pillar includes the detailed characteristics, physical laws and constraints on the system. The main objectives of this research are the development of models which will include: the system’s requirements; the system’s structure representation in term of different entities involved and the relationship between them; the system’s behaviours in terms of activities in different cases considered and transitions from one state to another as well as the interaction between the system and all the stakeholders. Keywords: Model Based Systems Engineering (MBSE), System Modelling Language (SysML), Renewable Energy systems, Hybrid power systems, photovoltaic systems, wind power systems.

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Mauger, Léo. "Generation of wind speed and solar irradiance time series for power plants with storage." Thesis, KTH, Energiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-181923.

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Sizing renewable energy power plants with storage devices needs new resource assessment. Global amount of energy available has to be replaced by time series to depict the resource as a function of time. This paper introduces methodology to generate time series for wind speed and solar irradiance with a granularity between 10minutes and 1seconde. Ground measurements and macro-date from satellite imagery are analyzed and processed to obtain long-term site-specific time series. Because renewable energy forecasting is a growing concern, a second part of the work presents how to modify previously generated profiles in order to obtain forecasts with an expected error.

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Schooley, David C. "Unit commitment and system reliability in electric utility systems with independent wind and solar generation." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/12917.

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Cohen, Matthew. "Avoided Water Cost of Electricity Generation for Solar PV and Wind Technologies in Southern California." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1301.

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The objective of this thesis is to provide a foundation for evaluating the water costs associated with electricity production to calculate the avoided water cost of energy for solar PV and wind technologies relative to coal, natural gas, nuclear, geothermal, concentrated solar thermal, and biomass. Water consumption is estimated for energy production (fuel extraction and preparation) and electricity generation (power plant operation) using the best available information from published articles. The quantity of water consumed for electricity production is monetized for a Southern California case study based on the water rates of Metropolitan Water District of Southern California (MET), which is the largest wholesale supplier of surface water in the United States. Water withdrawals are addressed but not included in the monetization of water consumption. Case studies of specific power plant’s water costs are used for comparison and demonstrate variation in water costs due to variations in water consumption. Water costs are estimated in terms of water cost ($) per unit energy generated (MWh). Since solar PV and wind energy are shown to have negligible water consumption relative to the other technologies, the water costs for each of the other electrical generation methods are equivalent to the water savings potential of solar PV and wind generated electricity. Compared to other evaluated electricity sources that could provide electricity to Southern California, solar PV and wind energy can save water worth $0.76/MWh for natural gas combined-cycle plants, $0.94/MWh for geothermal power plants, $1.01/MWh for biomass power plants, between $1.14 and $1.82 per MWh for concentrated solar thermal plants, $1.43/MWh for nuclear power plants, and $1.49/MWh for coal power plants. Results indicate that there are three processes that use substantial amounts of water: fuel extraction (for coal, natural gas, and nuclear), thermoelectric cooling of power plants and emissions controls such as carbon capture and sequestration. Carbon capture and sequestration are estimated to almost double the water consumption costs of coal and natural gas power plants. Of the evaluated technologies, only solar PV and wind do not require any of those three steps. Solar PV and wind energy can thus save the greatest value of water when displacing power plants that utilize (or may someday be required to utilize) all three of the major culprits of water consumption. Even the use of one of these processes (particularly thermoelectric cooling) results in substantial water consumption. Total water costs for each technology were normalized to the total expected electrical output of a typical capacity natural gas combined-cycle power plant to demonstrate the economies of scale of power production. Over a forty year lifespan of a typical natural gas power plant, total water consumption would result in $67 million worth of water (southern CA wholesale prices). To generate the same amount of electricity the total value of water consumption is estimated to be $83 million for geothermal plants, $89 million for biomass plants, $100 million to $160 million for concentrated solar thermal plants, $126 million for nuclear plants, and $131 million for coal power plants. The use of carbon capture and sequestration is expected to nearly double these total water costs. Compliance with environmental regulations can cause expenses much greater than water consumption. For example, mitigation costs for impingement and entrainment (a consequence of cooling water withdrawals) as well as the cost to convert to closed-loop cooling for environmental compliance can be considered costs associated with water usage. This is demonstrated by a case study about the Los Angeles Department of Water and Power regarding the elimination of once through cooling. The conversion to closed-loop cooling for the Haynes natural gas power plant is expected to cost $782 million, resulting in an estimated unit cost of $10.66/MWh. Finally, the economic benefits of the California Renewables Portfolio Standard are calculated with respect to water consumption. By holding hydroelectricity, geothermal, biomass and CST production constant and utilizing solar PV and wind to meet the 33% renewables target by 2020, a water value of $28.5 million/year can be conserved relative to meeting rising electricity demand with only natural gas combined-cycle generation. MET water rates increased 70% from 2008 to 2014. If water rates increase at the same rate over the next six years, the water savings of the Renewable Portfolio Standard would be 70% higher in 2020 dollars, equating to water savings of $48.4 million per year.

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Verma, Suruchi. "Comparative Analysis of Wind, Solar and Landfill Gases as Alternative Sources of Energy for Electricity Generation." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1262.

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The document reviews the current and projected electricity demand until the year 2030 along with the fuel mix. Several projections based on different agencies were studied in order to understand the trend of fuel mix projected to be used. Clearly, the fuel mix being used or projected is unsustainable. Depletion of fossil fuels, increasing demand and environmental impacts are some of the factors that emphasize the use of Alternative Sources of Electricity. Three of the upcoming Alternative Sources - Solar, Wind and Landfill Gases - are discussed and compared in the document. Based on the comparison, Landfill Gas projects seem to be very favorable, despite the higher costs related with such projects, several advantages over the other two Alternative Sources are discussed in the document. The several advantages of Landfill Gas projects, such as emissions reduction, better power quality, reduction in transmission losses, and several others are discussed in the document

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Ershad, Ahmad Murtaza. "Potential of Solar Photovoltaic and Wind Power Plants in Meeting Electricity Demand in Afghanistan." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1398944251.

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Pina, Aline Petean [UNESP]. "Singular value analyses of voltage stability on power system considering wind generation variability." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/123670.

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Os sistemas de transmissão em todo o mundo, que foram projetados e construídos para operar, predominantemente, com geração síncrona convencional, como a geração hídrica. Entretanto, agora se faz necessária a integração de energia renovável, tais como a energia eólica e energia solar. Estes geradores de energias renováveis estão localizados em locais ricos em recursos, causando uma injeções de potência em sistemas de transmissão, submetendo-os a indevidos esforços e obrigando-os a operar em novos pontos de operação. Em muitos sistemas de transmissão, a capacidade de integração se aproximou do limite, sendo necessárias atualizações para acomodar uma maior penetração de geração eólica. Os exemplos podem ser vistas na Alemanha, Ontario (Canadá) e Texas. Nestas situações, onde as capacidades do sistema de transmissão estão próximas do limite de operação, é importante para avaliar a estabilidade de tensão, considerando (a) a geração eólica e (b) possível efeito da incerteza na previsão. Neste trabalho, é proposta uma abordagem sistemática para estabilidade de tensão. Com a utilização de um algoritmo de fluxo de potência ótimo e da construção da matriz hessiana, será determinada a relação entre as mudanças nos valores mínimos singulares do sistema Jacobiano e as mudanças na injeção de potência no barramento em tempo real. Esta relação é usada para examinar o efeito da incerteza da previsão de energia eólica na estabilidade de tensão. O método proposto é usado para estudar os efeitos da incerteza sobre a estabilidade de tensão dos sistemas 6-barras, 57-barras e 118-barras do IEEE; do Sistema Sul Brasileiro reduzido e também foi usado um sistema real 600 barras. Os resultados são detalhados nesta tese
Transmission Systems worldwide, that were designed and built to operate with predominantly conventional synchronous generation, are advancing to integrate large amounts of renewable energy generators. These renewable generators are sited at resource-rich locations, causing a geographical shift in power injections into transmission systems, subjecting them to undue stress and making them operate in new states. In many transmission systems, capacities to integrate wind resource are exhausted or are being upgraded to accommodate higher wind generation penetration. Examples may be seen in Germany, Ontario (Canada) and Texas. In these situations, where transmission system capacities have been reached, it is important to assess voltage stability by considering (a) wind generation and (b) possible effect of uncertainty in forecast. In this work, a systematic approach of studying voltage stability is proposed. Using an optimal power flow algorithm, the Hessianmatrix of power balance equations is determined that relates changes in minimum singular values of system Jacobian to changes in bus-wise real power injections. This relationship is used to examine effect of uncertainty of wind power forecast on voltage stability. The proposed method is used to study the effects of uncertainty on system voltage stability of 6-bus, 57-bus and 118-bus IEEE and 45-bus South Brazilian test systems, for the real analyses is used 600-bus and results are reported. Considering the simplification of computation, the proposed method has a clear advantage compared to the conventional Jacobian technique using repeated OPF solutions

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Pina, Aline Petean. "Singular value analyses of voltage stability on power system considering wind generation variability /." Ilha Solteira, 2015. http://hdl.handle.net/11449/123670.

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Orientador: Percival Bueno de Araujo
Co-orientador: Bala Venkatesh
Banca: Dilson Amancio Alves
Banca: Fábio Bertequini Leão
Banca: Gideon Villar Leandro
Banca: Marcos Amorielle Furini
Resumo: Os sistemas de transmissão em todo o mundo, que foram projetados e construídos para operar, predominantemente, com geração síncrona convencional, como a geração hídrica. Entretanto, agora se faz necessária a integração de energia renovável, tais como a energia eólica e energia solar. Estes geradores de energias renováveis estão localizados em locais ricos em recursos, causando uma injeções de potência em sistemas de transmissão, submetendo-os a indevidos esforços e obrigando-os a operar em novos pontos de operação. Em muitos sistemas de transmissão, a capacidade de integração se aproximou do limite, sendo necessárias atualizações para acomodar uma maior penetração de geração eólica. Os exemplos podem ser vistas na Alemanha, Ontario (Canadá) e Texas. Nestas situações, onde as capacidades do sistema de transmissão estão próximas do limite de operação, é importante para avaliar a estabilidade de tensão, considerando (a) a geração eólica e (b) possível efeito da incerteza na previsão. Neste trabalho, é proposta uma abordagem sistemática para estabilidade de tensão. Com a utilização de um algoritmo de fluxo de potência ótimo e da construção da matriz hessiana, será determinada a relação entre as mudanças nos valores mínimos singulares do sistema Jacobiano e as mudanças na injeção de potência no barramento em tempo real. Esta relação é usada para examinar o efeito da incerteza da previsão de energia eólica na estabilidade de tensão. O método proposto é usado para estudar os efeitos da incerteza sobre a estabilidade de tensão dos sistemas 6-barras, 57-barras e 118-barras do IEEE; do Sistema Sul Brasileiro reduzido e também foi usado um sistema real 600 barras. Os resultados são detalhados nesta tese
Abstract: Transmission Systems worldwide, that were designed and built to operate with predominantly conventional synchronous generation, are advancing to integrate large amounts of renewable energy generators. These renewable generators are sited at resource-rich locations, causing a geographical shift in power injections into transmission systems, subjecting them to undue stress and making them operate in new states. In many transmission systems, capacities to integrate wind resource are exhausted or are being upgraded to accommodate higher wind generation penetration. Examples may be seen in Germany, Ontario (Canada) and Texas. In these situations, where transmission system capacities have been reached, it is important to assess voltage stability by considering (a) wind generation and (b) possible effect of uncertainty in forecast. In this work, a systematic approach of studying voltage stability is proposed. Using an optimal power flow algorithm, the Hessianmatrix of power balance equations is determined that relates changes in minimum singular values of system Jacobian to changes in bus-wise real power injections. This relationship is used to examine effect of uncertainty of wind power forecast on voltage stability. The proposed method is used to study the effects of uncertainty on system voltage stability of 6-bus, 57-bus and 118-bus IEEE and 45-bus South Brazilian test systems, for the real analyses is used 600-bus and results are reported. Considering the simplification of computation, the proposed method has a clear advantage compared to the conventional Jacobian technique using repeated OPF solutions
Doutor

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Washika, Tony. "Renewables Based Power generation for Kenya Pipeline Company." Thesis, KTH, Kraft- och värmeteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-131315.

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This study presents a Techno-economic assessment of a renewables based power generation project for PS 21, a Pumping Station for Kenya Pipeline Company located in Nairobi, Kenya. The load for the pumping station is 1135 kW Continuous. The assessment criteria used was levelized cost of energy. The hybrid renewable energy system software HOMER was used for assessment, and modeling was done using hourly TMY data for solar irradiance and wind. According to the results, Hybrid Solar PV-Wind- Battery renewable energy systems can supply adequate power for pumping station purposes. Optimization modeling at 2010 prices gave a levelized cost of energy of $0.2 per kWh for the most optimal solution which consisted of 2 No. 1650 kW Vestas V 82 Wind Turbines and 4070 kW of PV modules. This cost of energy just matches the purchase price from the National grid which varies between $0.14 and $0.2 per kWh, and therefore, the project is economically feasible. Mainly due to concerns of global warming, the view in the Kenyan government and society towards renewable energy is very favorable and the project is also politically and socially feasible. Sensitivity analysis demonstrated that wind energy is more viable than solar PV energy in areas of high wind speeds, with about 7.5 m/s annual average wind speeds. The results show that the levelised cost of energy may be significantly decreased in future due to the fact that the cost of PV modules is progressively reducing. Payments for CERs under CDM mechanism of the Kyoto Protocol would lower the levelised cost of energy further. The Project was found to be feasible.

I was a distance student and did the presentation online via centra.

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Ryberg, David Severin Verfasser], Detlef [Akademischer Betreuer] [Stolten, and Michael [Akademischer Betreuer] Lauster. "Generation lulls from the future potential of wind and solar energy in Europe / David Severin Ryberg ; Detlef Stolten, Michael Lauster." Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/123131737X/34.

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Beck, Osmer DeVon. "Distributed Renewable Energy Generation and Landscape Architecture: A Critical Review." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/641.

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Governments and utility organizations around the world have mandated and provided incentives for new distributed renewable energy generation (DREG) capacity, and market projections indicate strong growth in distributed renewable energy generation installations in the coming years. New distributed renewable energy generation utilities, by definition, will be primarily located in built environments near consumers; these utilities are often planned and designed by landscape architects, yet no evidence-based, distributed renewable energy generation research is explicitly done by landscape architects or recognizes the role landscape architects play in planning and designing these spaces. The research and analysis provided by this study indicates that distributed renewable energy generation lacks a strong foundation as an independent concept which could benefit from clear broad phraseology linked to organized sub-terms/phrases for specific forms of DREG, that there has been some research done on topics familiar to landscape architects, that more needs to be done to meet important research questions and recommendations already posed, and that landscape architects are positioned to contribute to future distributed renewable energy generation research.

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Siqueira, Jair Antonio Cruz [UNESP]. "Desempenho de um sistema híbrido eólico-fotovoltaico de pequeno porte para energização rural." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/101808.

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A geração de energia elétrica a partir de fontes renováveis começou a apresentar maior interesse a partir da crise do petróleo na década de 70. De lá pra cá, entre outros recursos energéticos renováveis, a utilização do potencial da energia solar e eólica tem crescido significativamente. A integração de sistemas de geração eólica e fotovoltaica com armazenamento de energia em baterias tem-se apresentado como uma forma de geração em que os problemas decorrentes da variabilidade na intensidade da energia eólica e solar, tornam-se possíveis de mitigação, seja pela complementação entre uma fonte e outra, ou pela maior estabilidade configurada à geração do sistema. Com base neste contexto, este trabalho teve o objetivo de avaliar o desempenho um sistema híbrido de energia eólico-fotovoltaico de pequeno porte, para a eletrificação de uma propriedade rural, avaliando-se o efeito das variáveis climáticas sobre a produção energética do sistema. O trabalho foi desenvolvido no Laboratório de Energização Rural do Departamento de Engenharia Rural da UNESP-FCA. Para a realização do trabalho, foi instalado um sistema híbrido (solar + eólico), composto por um aerogerador e um painel fotovoltaico, complementado por uma bateria para armazenamento da energia elétrica gerada, controlador de carga e inversor de tensão. O sistema foi configurado para atender as cargas de uma pequena residência rural. Para avaliação das características do potencial da energia solar e eólica, utilizaram-se os dados de uma estação meteorológica instalada no local. Um sistema de aquisição de dados foi programado para coletar os parâmetros meteorológicos e elétricos do experimento a cada 10 segundos, apresentando a média dos valores coletados a cada 5 minutos. A coleta dos dados foi realizada durante um ano, diuturnamente, para avaliar a influência das horas...
The electric energy generation from renewable sources, began to present larger interest in the petroleum crisis in 1970 decade. Since then, among other renewable energy resources, the use of the solar energy and wind energy potential have been growing significantly. The integration of wind and photovoltaic generation systems has been presenting as a generation form where the current problems of the variability in the wind and solar energy intensity, become possible of mitigation due to the complementation of both a sources, or for the larger stability given to the generation system. Based in this context, this work had the objective of evaluating a small wind-photovoltaic hybrid energy system for a rural electrification, with the evaluation of the climatic variables effect on the system energy production. The work was developed in the Laboratory of Rural Electrification of the UNESP-FCA Rural Engineering Department. For the accomplishment of the work, a small wind-photovoltaic hybrid system was installed, composed by an wind generator and a photovoltaic panel, complemented with a battery for the generated electric energy storage, a charge controller and an inverter. The system was configured for small rural residence load supply. For solar and wind energy potential characteristics evaluation, the data of a meteorological station installed in the place were used. A data acquisition system was programmed to collect the meteorological and electric parameters of the experiment every 10 seconds, calculating the average values collected every 5 minutes. The data collection was carried out during one year, daily, to evaluate the influence of the day hours and of the seasons changes on the hybrid system energy generation and its components. The collected data were integrated, and it was determined the values of the solar energy, wind energy, photovoltaic generation, wind generation and hybrid system...(Complete abstract click electronic access below)

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Martinez-Cesena, Eduardo Alejandro. "Real options theory applied to renewable energy generation projects planning." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/real-options-theory-applied-to-renewable-energy-generation-projects-planning(280f3df5-f1be-4999-bd33-3931ce3cdbbd).html.

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The existing environmental threats and the ever increasing global dependence on electric power highlight the importance of producing power in a sustainable manner. In accordance, it is vital to attract investments in electricity generation projects based on renewable energy sources, also called renewable energy projects (REP). This poses a challenge, as REP tend to be less financially competitive than their fossil fuel based counterparts. Moreover, the power grid has to be upgraded to integrate large amounts of RESs in an efficient and economic manner. An appealing alternative to enhance the financial appealing of REP is to improve the techniques used for their assessment. These tools produce robust and economically sound assessments, but tend to undervalue REP and other projects under uncertainty, as they neglect the flexibility of the projects to be adjusted in response to uncertainty. This can be corrected by extending the tools with the aid of real options (RO) theory. RO theory can be used to extend assessment techniques to value flexibility derived from the projects, their management, and even their environment, which can be used to enhance the financial value of REP in the changing power sector. In addition, the scope of RO theory is increasing to address flexibility in the design of the projects. Therefore, the theory can drive investments in REP and motivate the design of more profitable projects. This research project seeks to analyse the potential of RO theory to increase the financial worth of different types of REP in the current and changing power sector. The novelties of this research are that it expands RO theory by addressing the flexibility within the design of the projects, the potential of RO theory to manage uncertainties that are exclusive to the projects or typical in the power sector, and other relevant areas of research interest. The research produced several RO methodologies to model the planning, operation, and design of hydropower projects, wind power projects, and solar photovoltaic projects in existing power sector environments and environments characterised by high penetration of RESs and consumers with demand response capabilities. The results demonstrate the applicability of RO theory to enhance the financial value of different types of REP under a wide range of circumstances.

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Waheed, Amna. "To Electrify a Flood Affected Village in Sajawal, Pakistan by Utilizing the Available Renewable Energy Resources." Thesis, KTH, Kraft- och värmeteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149865.

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Pakistan, though being one of the most rich in renewable energy resources, faces serious energy crises and has a shortfall of about 6 GW electric energy. Most of the resources are untapped until today. The fuel for electricity production is being imported and is of high cost. The government is trying to fulfill the energy requirements of the industries and urban areas where rural areas are at the lowest priority. Pakistan was hit by flood disaster in 2010. There are number of organizations, governmental and private, that are trying to provide shelters and basic necessities to the flood affecties even until today. Village Goth Mehdi Farm in Sajawal area of Sindh is one of the examples of a newly built village for the flood affecties. It has been built with the help of Pakistan Navy, however, the village is bereft of electricity. This report presents three different designs for the electrification of the flood affected village, consisting of 20 houses, a mosque, a community centre, toilets and street lighting, in Sajawal, Pakistan by utilizing available renewable energy resources using sustainability approach. Supply of clean water and energy for cooking purposes was also investigated. However, it was identified in the site visit that villagers were using a mechanical hand pump to pump the underground clean water for daily usage which did not require further alternative. The village is surrounded by wheat fields and trees, and villagers used wood as fuel for cooking. Dehydrated animal dung of cattle was also used as fuel source. The Sajawal area is located in the wind corridor of Sindh and also receives sun light of high insolation level. Thus, wind turbine (WT) or/and PV module can be used for electricity generation, respectively. Based on such advantages three electricity generating systems are proposed. Option #1: solar energy by using 19 kilowatt Photovoltaic (PV) system with off grid inverter and battery bank to cater the load of the village, Option #2: wind energy by using 20 kilowatt wind turbine with a battery backup and Option #3: hybrid PV and WT system with 5.8 kilowatt PV system combine with 10 kilowatt wind turbine and battery backup. These systems have been designed by keeping social, economical and environmental aspects in account. The financial comparison showed that the option # 1 required highest amount of capital cost with respect to other options, while option # 3 needed lowest initial investment for installation. Moreover Option 1, solar system, was found to be the most expensive option when battery replacements (every 3 years) were considered over a 20 years life time. Option 3, hybrid wind and solar system, was concluded to be the most economical solution for the Goth Mehdi farms.

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Campos, Victor Arruda Ferraz de. "Aspectos técnicos, econômicos e ambientais de sistemas híbridos aplicados em edificações familiares e propriedades rurais /." Guaratinguetá, 2019. http://hdl.handle.net/11449/183561.

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Orientador: José Luz Silveira
Resumo: Nesse trabalho são apresentadas propostas de sistemas híbridos de geração de energia (SHGE) para o fornecimento de energia elétrica. O Caso 1 propõe um SHGE conectado à rede elétrica (on-grid) para atender a demanda elétrica de edifícios urbanos. O Caso 2 propõe um SHGE aplicado a áreas rurais com disponibilidade de rede elétrica local. O Caso 3 considera uma propriedade rural sem rede elétrica local, portanto propõe-se um SHGE com armazenamento de energia (off-grid). Os três casos são analisados em termos técnicos, econômicos e ambientais para três cidades brasileiras: Fortaleza (CE), Guaratinguetá (SP) e Florianópolis (SC). Para o dimensionamento do SHGE, desenvolve-se um algoritmo de otimização cuja função objetivo é a minimização do custo de geração de energia elétrica. Utiliza-se o software LINGO para a determinação da solução ótima do arranjo SHGE para cada caso. A análise econômica leva em consideração os custos de investimento, operação e manutenção para determinação do período de retorno (payback) e da receita anual esperada. A análise ambiental é feita através do cálculo da eficiência ecológica dos sistemas de geração de energia estudados. Os resultados mostram que o Caso 2 – SHGE on-grid: Propriedade Rural possui o menor período de retorno de investimento, entre 1 e 2 anos. Para todos os casos, a cidade de Fortaleza é onde evidencia-se o menor custo de investimento dos SHGE e, consequentemente, menor custo de geração de eletricidade dada seus elevados potenciais en... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

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Avella, Ruiz Jorge Mario [UNESP]. "Aspectos técnicos, econômicos e ambientais da implementação de energia eólica e solar fotovoltaica em edifícios." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143418.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Atualmente, governos de todo o mundo estão se preocupando pelos efeitos das economias, indústrias e políticas no meio ambiente, criando regulações para fomentar a utilização de tecnologias menos poluidoras. No Brasil, a Agência Nacional de Energia Elétrica (ANEEL) é o ente federal de promover a implementação de fontes renováveis para a geração de eletricidade. A ANEEL mediante a resolução Nº 482/2012 permite aos usuários finais a instalação de tecnologias renováveis para produzir eletricidade para suas cargas elétricas, incrementando assim a porcentagem de energias alternativas na matriz energética nacional, considerando também os projetos renováveis de grande escala. Neste trabalho, realizou-se um estudo para conhecer a viabilidade da implementação de sistemas híbridos de geração de energia elétrica (SHGEEE) em edifícios, utilizando energia eólica e solar fotovoltaica. A metodologia para a análise técnica consistiu em obter o consumo de energia elétrica de edifícios residenciais de baixa, média e alta renda no Brasil, para assim com base nos recursos eólicos e solares de Fortaleza (CE) e Lagoa Santa (MG), realizar o balanço energético anual e desta forma dimensionar os SHGEE para seis cenários estudados. Baseado nos resultados técnicos, a metodologia econômica analisou a viabilidade financeira de implementar no Brasil os seis SHGEE dimensionados utilizando engenharia econômica para conhecer o investimento dos projetos, os custos da energia elétrica gerada pelas plantas híbridas e o período de retorno do investimento. A análise ambiental fundamentou-se em determinar a quantidade de dióxido de carbono economizado e a eficiência ecológica de cada cenário estudado considerando as fontes de energia da rede elétrica. Os resultados obtidos mostraram que os SHGEE são capazes de fornecer a eletricidade para as cargas do edifício. Os períodos de retorno do investimento dos seis SHGEE dimensionados se encontram dentro da vida útil das plantas. Em termos ambientais, as tecnologias utilizadas nos SHGEE não são totalmente não poluentes, no entanto, comparando com outras fontes de energia, estas têm baixo impacto ambiental. Conclui-se, que as aplicações de energia renováveis para edifícios são viáveis técnica, econômica e ambientalmente no Brasil.
Nowadays, governments around the world are worried about the effects of economies, industries and environment policies, making them to create regulations to encourage the use of less polluting technologies. In Brazil, the National Electric Energy Agency (ANEEL) is the federal entity to promote the implementation of renewable sources for generating electricity. ANEEL Resolution No. 482/2012 allows end users to install renewable energy sources to produce electricity for their electrical charges, increasing the percentage of alternative energy in the national energy matrix, in addition of renewable projects of large scale. In this work was made a study to know the feasibility of implementing hybrid electricity generation systems SHGEE in buildings, using wind power and solar photovoltaic energy. The methodology for the technical analysis consisted in obtaining the electricity consumption of a low, medium and high income residential building in Brazil, thus based on wind and solar resources in Fortaleza (Ceara State) and Lagoa Santa (Minas Gerais State), performing annual energy balance for dimensioning SHGEE for six scenarios studied. Considering the technical results, the economic methodology analyzed the financial feasibility of implementing in Brazil six SHGEE sized applying economic engineering and determining the project investments, the costs of electricity generated by hybrid plants and the payback period of the investment. In the environmental analysis determined the amount of carbon dioxide saved and the ecological efficiency of each scenario studied considering the sources of utility grid. The results showed that SHGEE are capable of supplying electricity to loads of the building. It is not generated electricity in all months of the year, however, with the normativity, it compensates with the months of surplus production of electricity. The return period of the investment of the six scaled SHGEE are within the lifetime of the plants. In environmental terms, the technology used in SHGEE are not completely non-polluting, nevertheless, compared with other energy sources, they have low environmental impact. In general, renewable energy applications for buildings are feasible technically, economically and environmentally in Brazil.

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Siqueira, Jair Antonio Cruz 1969. "Desempenho de um sistema híbrido eólico-fotovoltaico de pequeno porte para energização rural /." Botucatu : [s.n.], 2005. http://hdl.handle.net/11449/101808.

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Orientador: Onivaldo José Seraphim
Banca: Celso Luiz da Silva
Banca: Carlos Eduardo C. Nogueira
Banca: Samuael N. Melegari de Souza
Banca: Celso Eduardo Lins de Oliveira
Resumo: A geração de energia elétrica a partir de fontes renováveis começou a apresentar maior interesse a partir da crise do petróleo na década de 70. De lá pra cá, entre outros recursos energéticos renováveis, a utilização do potencial da energia solar e eólica tem crescido significativamente. A integração de sistemas de geração eólica e fotovoltaica com armazenamento de energia em baterias tem-se apresentado como uma forma de geração em que os problemas decorrentes da variabilidade na intensidade da energia eólica e solar, tornam-se possíveis de mitigação, seja pela complementação entre uma fonte e outra, ou pela maior estabilidade configurada à geração do sistema. Com base neste contexto, este trabalho teve o objetivo de avaliar o desempenho um sistema híbrido de energia eólico-fotovoltaico de pequeno porte, para a eletrificação de uma propriedade rural, avaliando-se o efeito das variáveis climáticas sobre a produção energética do sistema. O trabalho foi desenvolvido no Laboratório de Energização Rural do Departamento de Engenharia Rural da UNESP-FCA. Para a realização do trabalho, foi instalado um sistema híbrido (solar + eólico), composto por um aerogerador e um painel fotovoltaico, complementado por uma bateria para armazenamento da energia elétrica gerada, controlador de carga e inversor de tensão. O sistema foi configurado para atender as cargas de uma pequena residência rural. Para avaliação das características do potencial da energia solar e eólica, utilizaram-se os dados de uma estação meteorológica instalada no local. Um sistema de aquisição de dados foi programado para coletar os parâmetros meteorológicos e elétricos do experimento a cada 10 segundos, apresentando a média dos valores coletados a cada 5 minutos. A coleta dos dados foi realizada durante um ano, diuturnamente, para avaliar a influência das horas...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The electric energy generation from renewable sources, began to present larger interest in the petroleum crisis in 1970 decade. Since then, among other renewable energy resources, the use of the solar energy and wind energy potential have been growing significantly. The integration of wind and photovoltaic generation systems has been presenting as a generation form where the current problems of the variability in the wind and solar energy intensity, become possible of mitigation due to the complementation of both a sources, or for the larger stability given to the generation system. Based in this context, this work had the objective of evaluating a small wind-photovoltaic hybrid energy system for a rural electrification, with the evaluation of the climatic variables effect on the system energy production. The work was developed in the Laboratory of Rural Electrification of the UNESP-FCA Rural Engineering Department. For the accomplishment of the work, a small wind-photovoltaic hybrid system was installed, composed by an wind generator and a photovoltaic panel, complemented with a battery for the generated electric energy storage, a charge controller and an inverter. The system was configured for small rural residence load supply. For solar and wind energy potential characteristics evaluation, the data of a meteorological station installed in the place were used. A data acquisition system was programmed to collect the meteorological and electric parameters of the experiment every 10 seconds, calculating the average values collected every 5 minutes. The data collection was carried out during one year, daily, to evaluate the influence of the day hours and of the seasons changes on the hybrid system energy generation and its components. The collected data were integrated, and it was determined the values of the solar energy, wind energy, photovoltaic generation, wind generation and hybrid system...(Complete abstract click electronic access below)
Doutor

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STECHER, LUIZA C. "Cálculo de viabilidade econômica de fontes alternativas de energia considerando seus custos ambientais para pequenas comunidades da região nordeste brasileira." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10619.

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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Júnior, José Arnaldo Villamarim. "Análise da viabilidade técnica-econômica de um sistema eólico-fotovoltaico com conexão à rede elétrica suprindo uma estação rádio base de telefonia celular no estado de São Paulo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-23012017-150207/.

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O desenvolvimento sustentável busca satisfazer as necessidades humanas no presente sem comprometer a capacidade de satisfazer as necessidades da sociedade no futuro. Com a demanda crescente por energia, a diversificação da matriz energética atual e a busca por fontes renováveis complementares tornam-se cada vez mais importantes. Entre essas fontes as energias provenientes do sol e das correntes de ar se destacam como duas das mais promissoras e, na busca pelo aproveitamento direto da radiação solar e da energia cinética oriunda dos ventos, diversas tecnologias tem sido estudadas e desenvolvidas. No Brasil, segundo a Agência Nacional de Energia Elétrica ANEEL (2016) as fontes de energia eólica e solar fotovoltaica representam pouco mais de 6% do total considerando os empreendimentos em operação, o que indica uma oportunidade para a expansão da geração de energia elétrica utilizando estas fontes limpas. Considerando, então, a relevância que a geração renovável de energia assume nesse contexto, este trabalho detalha a implantação, discute os resultados obtidos e estuda a viabilidade técnica-econômica da instalação de um projeto de geração eólico isolado e fotovoltaico com conexão à rede elétrica de distribuição, sob o âmbito das Resoluções Normativas número 482/2012 e 687/2015 da ANEEL, fornecendo energia a uma estação rádio base de telefonia celular no estado de São Paulo.
Sustainable development seeks to meet human needs in the present without compromising the ability to meet the needs of society in the future. With the growing demand for energy, the diversification of the energy matrix and the search for complementary renewable sources become increasingly important. Among these sources, the energy from the sun and air currents stand out as two of the most promising and in the search for direct use of solar radiation and kinetic energy from the wind, several technologies have been studied and developed. In Brazil, according to the Agência Nacional de Energia Elétrica (ANEEL 2016) the sources of photovoltaic solar and wind energy account for just over 6% of total considering the projects in operation, indicating an opportunity for the expansion of electricity generation using these clean sources. So considering the importance that renewable energy generation takes this context, this paper details the implementation, discusses the results and assessing the technical and economic feasibility of installing a isolated wind generation and a photovoltaic generation project with connection to the electrical distribution network, under the scope of Normative Resolution number 482/2012 and 687/2015 of ANEEL, providing power to a radio station cellular base in the state of São Paulo.

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Gersema, Gerke [Verfasser], Gunther [Akademischer Betreuer] [Gutachter] Friedl, and David [Gutachter] Wozabal. "Risk Management for Renewable Energy Generation : How to Deal with the Uncertainty of Wind and Solar Power / Gerke Gersema ; Gutachter: David Wozabal, Gunther Friedl ; Betreuer: Gunther Friedl." München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/1143826353/34.

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Alraddadi, Musfer. "Toward Fully Renewable Power Systems in Regions with HighSolar Irradiation: Long-Term Planning and Operations." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1605791220407664.

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De, Jong Pieter. "Forecasting, integration, and storage of renewable energy generation in the Northeast of Brazil." Escola Politécnica, 2017. http://repositorio.ufba.br/ri/handle/ri/24167.

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CAPES e FAPESB.
As a result of global climate change, during the coming decades less rainfall and higher temperatures are projected for the Brazilian Northeast (NE). Consequently these regional climatic changes could severely impact hydroelectric generation in the NE as well as influence solar and wind power potential. The ongoing drought in the Brazilian NE region has caused hydroelectric generation to decline substantially during the last 5 years and in 2016 hydroelectricity only supplied 25% of the NE’s total demand. In contrast, wind power supplied 30% of demand and is expected to generate 55-60% of the NE’s electricity supply by 2020. Therefore, this paper is focused on both short term forecasting and long-term projections of renewable energy generation and resource availability. It also explores the economic, environmental and technical feasibility of renewable energy integration in the NE region of Brazil. First, the long-term impacts of climate change on the NE region’s hydroelectric and wind energy production are analysed. Particular attention is paid to the long-term projections of annual rainfall and streamflow in the São Francisco basin which could decline by approximately 47% and 80%, respectively, by 2050. On the other hand, wind energy potential is projected to increase substantially during the same period. This thesis also estimates the economic, social, and environmental viability of renewable and non-renewable generation technologies in Brazil. The Levelised Cost of Electricity (LCOE) including externalities is calculated for several different case study power plants, the majority of which are located in the Brazilian NE. It was found that wind power becomes the cheapest generation technology in the NE region, once all externality and transmission line costs are taken into consideration. The LCOE for the entire Northeast’s generation matrix is calculated for various configurations, including scenarios in which hydroelectric generation is restricted due to drought conditions. It was concluded that a generation mix in which wind power replaces all fossil fuel generation by 2020, could feasibly reduce the overall LCOE in the region by approximately 46% and substantially decrease CO2eq emissions. Two different methods are used to examine the limits of integrating high penetrations of variable renewable generation technologies into a power system with a large proportion of hydroelectric capacity. In the first method existing wind generation data from 16 wind farms is extrapolated in time and space, while the second method uses a numerical weather prediction model to simulate future wind energy generation in the NE region. Considering the minimum generation requirements of the São Francisco’s hydroelectric dams, the maximum wind energy penetration in the NE region is estimated to be approximately 50% before significant amounts of energy would need to be curtailed or exported to other Brazilian regions. Finally, this thesis reviews additional literature on energy storage and the impact of large scale variable renewable energy integration on grid stability and power quality. It was found that there are several existing technologies such as power factor and voltage regulation devices that can resolve these issues.
Como consequência da mudança climática global, nas próximas décadas menos precipitação e temperaturas mais altas são projetados para Nordeste (NE) do Brasil. Consequentemente, essas mudanças climáticas regionais podem afetar severamente a geração hidrelétrica no NE, bem como influenciar o potencial de energia solar e eólica. A seca atual nessa região do Brasil fez com que a geração hidrelétrica caísse substancialmente durante os últimos 5 anos e em 2016, as usinas hidrelétricas apenas forneceram 25% da demanda total do NE. Em contraste, a energia eólica forneceu 30% da demanda e deverá gerar 55-60% do fornecimento de energia elétrica do NE até 2020. Portanto, este trabalho está focado tanto na previsão a curto quanto projeções a longo prazo da geração de energia renovável e disponibilidade de recursos. Ele também explora a viabilidade econômica, ambiental e técnica da integração de energias renováveis na região NE. Primeiramente, os impactos de longo prazo das mudanças climáticas na produção hidrelétrica e eólica da região NE são analisados. Especial atenção é dada às projeções de longo prazo de precipitação anual e fluxo na bacia do São Francisco, que podem diminuir em aproximadamente 47% e 80%, respectivamente, até 2050. Por outro lado, prevê-se que o potencial da energia eólica aumente substancialmente durante o mesmo período. Esta tese também estima a viabilidade econômica, social e ambiental das tecnologias de geração renováveis e não-renováveis no Brasil. O custo nivelado de energia elétrica (LCOE), incluindo externalidades, é calculado para diversas usinas de estudo de caso, a maioria localizada no NE. Verificou-se que, a energia eólica se torna a tecnologia de geração mais barata na região NE, uma vez que todos os custos de externalidades e de linhas de transmissão são levados em consideração. O LCOE para a matriz de geração do Nordeste é calculado para várias configurações, incluindo cenários em que a geração hidrelétrica é restrita devido às condições de seca. Concluiu-se que, uma mistura de geração em que a energia eólica substitui toda a geração de combustíveis fósseis até 2020, poderia reduzir o LCOE na região em aproximadamente 46% e diminuir substancialmente as emissões de CO2eq. Dois métodos diferentes são usados para examinar os limites da integração de altas penetrações de tecnologias de geração renovável variáveis em um sistema de energia com uma grande proporção de capacidade hidrelétrica. No primeiro método, dados de geração eólica existentes de 16 parques eólicos são extrapolados no tempo e no espaço, enquanto o segundo método utiliza um modelo de previsão numérica de tempo para simular a futura geração de energia eólica na região NE. Considerando as exigências mínimas de geração das hidrelétricas do São Francisco, estima-se que a penetração máxima de energia eólica na região NE seja de aproximadamente 50% antes que quantidades significativas de energia precisem ser desperdiçadas ou exportadas para outras regiões brasileiras. Finalmente, esta tese examina literatura adicional sobre armazenamento de energia e o impacto da integração de energia renovável variável em larga escala na estabilidade da rede elétrica e na qualidade da energia. Verificou-se que existem várias tecnologias existentes, como dispositivos de regulação de fator de potência e tensão que podem resolver estes problemas.

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Darbyshire, James. "Multi-function power electronic interface for hybrid mini-grid systems." Thesis, Curtin University, 2010. http://hdl.handle.net/20.500.11937/2394.

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In the past five years, global interest regarding the development of renewable energy technologies has significantly increased. The conventional electric power generation methods sourced from fossil fuels is now problematic, from both the supply and emission points of view. Fossil fuels are non-renewable limited resources that have taken millions of years to form; eventually they will be exhausted and the current cost of automotive fuel is evidence of them becoming diminished. The carbon dioxide emissions created through the energy conversion process are causing an increase in the overall atmospheric concentrations, which through global warming may have serious consequences for humanity.Natural sources of energy production can be derived from the Sun through the use of solar and wind generation methods. Converting these sources to electricity requires the technology of power electronics, the central area of research for this dissertation. Solar energy can most easily be harnessed through the photo-electric effect which creates DC electricity. However, the majority of electric loads and transmission require AC electricity. The inverter is the electronic device required for this power conversion. Wind turbines usually create variable voltage and frequency AC that is rectified to DC and then converted to grid type AC through an inverter.Voltage source inverters, their topologies and control are investigated within this dissertation. Voltage control methods are adopted for both stand-alone and grid connected techniques where control of active and reactive power is required. Current control techniques in the form of PI and hysteresis are applied to allow novel interfaces between generation sources to be achieved. Accurate control of the power electronics allows an enhancement in the power production from the renewable energy source. The power electronic device of the DC-DC converter, either buck or boost is controlled to allow the renewable resource to operate at its optimum power point. The control aspects and algorithms of these converters are central to this research. The solar algorithms of perturb and observe, and incremental conductance are developed with the latter being more favourable to changing levels of irradiation. The author draws a parallel between rapidly changing solar conditions with normally changing wind states. This analogy with an understanding of the mechanics of PMSG allows a novel wind MPPT algorithm to be developed which is simulated in PSIM. Methods to analyse the usefulness of the algorithm are developed and general conclusions are drawn.Another aim central to the research is the efficient combination of renewable energy sources into a single reliable power system. This forms the multi-function aspect of the research. The interconnection of the sources on the AC or DC sides is investigated for both stand-alone and grid connected topologies. A requirement of the stand-alone system is to provide power when no renewable resources are available causing some form of energy storage to be utilised. Conventional batteries are used, causing the VC-VSI to become bi-directional allowing charging. This is simulated in PSIM and demonstrated as part of the Denmark and Eco Beach projects. Many differing topologies of stand alone, grid connected and edge of grid systems are developed, simulated and some are demonstrated.While investigating the currently used topologies the author invents the novel complimentary hybrid system concept. This idea allows a single inverter to be used to feed energy from either the wind or solar resource. With careful engineering of the PV array and wind turbine characteristics only a small loss of energy is caused, deemed the crossover loss. This original concept is mathematically modelled, simulated and demonstrated with results presented from the Denmark project. The strength of this idea is from the quite complimentary nature of wind and solar resources, for only a small proportion of the year are high solar and strong wind conditions occurring simultaneously.Compared to a solar resource, the wind resource is much more complicated to model. An analysis of readily available wind source data is presented with a statistical analysis of the scaling methods; a novel box and whiskers plot is used to convey this information. New software is presented to allow a more accurate and digital model of a power curve to be recreated, allowing a more precise annual energy generation calculation. For various wind turbines a capacity factor analysis is presented with its disadvantages explained. To overcome these issues the concepts of economic efficiency and conversion efficiency are explained. These prevent some of the typical methods to enhance the standard capacity factor expression. The combination of these three methods allows selection of the most suitable wind turbine for a site.The concept of a mini-grid is an isolated power generation and distribution system, which can have its renewable energy sources, centralised or decentralised. The methods used to coalesce conventional generation with renewable energy technology forms another key piece of this research. A design methodology for the development of a hybrid power system is created with examples used from projects attributed to the author. The harmonising of the renewable energy sources with the conventional generation while providing a stable and robust grid is explained in detail with respect to the generator loading and control. The careful control of the renewable resource output is shown to allow a greater overall penetration of renewable energy into the network while continuing network stability. The concept of frequency shift control is presented, simulated and demonstrated with reference to the Eco Beach project. This project epitomises much of the research that has been presented in this dissertation. It combines centralised and decentralised inverters, with battery storage and the control of diesel generators. An overall controller dictates the optimum times to charge or draw from the battery based upon the local environmental and time of day variables. Finally, the monitoring aspects of this project are representative of a future smart grid where loads may be shed on demand through under frequency or direct control.

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Söderberg, Felix. "Foundations for generations : Sustainability in wind power planning." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-272994.

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The demand for sustainable energy generation is constantly growing and with it comes higher demands on minimizing greenhouse gas emissions. This means not only finding ways of cleaner production processes from cradle to grave but also reducing the material use, extending the lifespan of constructions and finding ways to re-use and re-cycle materials. The fastest expanding energy generation type in Sweden is wind energy. The wind turbines continue to grow in size, meaning that the foundations also need to grow in order to balance the forces they are subjugated to. The aim of this thesis is to investigate which type of windmill foundation could be more sustainable and which geotechnical parameters control the choice of foundation to later explore ways to create GIS tools that can help to map where more sustainable wind power parks can be placed. Through literature reviews and interviews with different experts in the field it was decided upon which foundation type would be considered the most economically and ecologically sustainable as well as the parameters that control the choice during the projection and construction phase. The necessary data was collected and by using ModelBuilder in ArcGIS three tools were built to, in different ways, show where would be the optimal placement of wind power parks in regard to foundation type. Rock-anchored foundations were discovered to be the most sustainable type of foundation. It uses less raw materials, minimizes the area of impact on surrounding terrain, needs the shallowest excavation, which minimizes groundwater drainage, and has a higher potential for supporting new generations of windmills. The first tool shows where it is practically feasible to place these foundations and the second tool where it is recommended to place these foundations in order to minimize risks to ecosystems and infrastructure. The third tool uses a multi-criteria evaluation method to show the optimal placement of the wind power parks in regard to distance to the electrical grid, roads and other parameters. The foundation method found to be the most economically and ecologically sustainable is the rock- anchored foundation, mainly for requiring much less material. The tools developed in ArcGIS can be used for crude estimations for placement of wind power parks but can be refined by using data with higher resolution.
Efterfrågan på hållbar energiproduktion växer ständigt och med den kommer högre krav på att minimera utsläpp av växthusgaser. Detta innebär inte bara att utveckla rena produktionsprocesser utan också minska materialanvändningen, förlänga livslängden för konstruktioner och hitta sätt att återanvända och återvinna material. Den snabbast växande energiproduktionstypen i Sverige är vindkraft. Vindkraftverken fortsätter att växa i storlek, vilket innebär att grundläggningen också behöver växa för att balansera krafterna de utsätts för. Syftet med denna avhandling är att undersöka vilken typ av grundläggningsmetod som kan vara mer hållbar och vilka geotekniska parametrar som styr valet av det, för att senare utforska sätt att skapa GIS-verktyg som kan hjälpa till att kartlägga där mer hållbara vindkraftsparker kan placeras. Genom litteraturgranskningar och intervjuer med olika experter inom området beslutades vilken grundläggningsmetod som skulle betraktas som den mest ekonomiskt och ekologiskt hållbara samt de parametrar som styr valet under projekterings- och konstruktionsfasen. De nödvändiga uppgifterna samlades in och med hjälp av ModelBuilder i ArcGIS byggdes tre verktyg för att på olika sätt visa var en optimal placering av vindkraftsparker med avseende på grundtyp kan placeras. Bergförankrad grundläggning ansågs vara den mest hållbara grundläggningsmetoden. Den använder mindre råmaterial, minimerar påverkan på omgivande terräng, behöver den grundaste utgrävningen vilket minimerar dränering av grundvatten och har en högre potential för att stödja nya generationer av vindkraftverk. Det första verktyget visar var det är praktiskt möjligt att placera dessa fundament och det andra verktyget där det rekommenderas att placera dessa fundament för att minimera riskerna för ekosystem och infrastruktur. Det tredje verktyget använder en multikriterieanalys (MCA) med flera kriterier för att visa optimal placering av vindkraftsparkerna när det gäller avstånd till elnätet, vägar och andra parametrar. Grundläggningsmetoden som har visat sig vara den mest ekonomiskt och ekologiskt hållbara är den bergförankrade grunden, främst för att den kräver mycket mindre material. Verktygen som utvecklats i ArcGIS kan användas för grova uppskattningar för placering av vindkraftsparker, men kan förfinas genom att använda data med högre upplösning.

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Fallows, R. A. "Studies of solar wind throughout a solar cycle." Thesis, Aberystwyth University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594095.

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Chen, Christopher H. K. "Anisotropy of solar wind turbulence." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/6375.

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As well as being of fundamental interest, understanding plasma turbulence is important for many areas of astrophysics and space physics that remain to be fully understood, such as accretion disk dynamics, the origin of cosmic rays and coronal heating. The anisotropy with respect to the magnetic fi eld is central to understanding plasma turbulence, but this has only recently started to be measured in detail. The solar wind provides a unique opportunity to study this anisotropy due to the range of high precision in situ measurements available. In this thesis, the anisotropy of solar wind turbulence is measured using data from the multi-spacecraft Cluster mission. At all scales measured, the fluctuations are found to be spatially anisotropic: elongated along the direction of the magnetic field. The scaling of the turbulence is also anisotropic, with a steeper spectral index in the direction parallel to the local magnetic fi eld. This is consistent with the fluctuations being in critical balance: having approximately equal linear wave timescales and nonlinear eddy decay timescales. At large scales, the anisotropy of the density and parallel magnetic fi eld fluctuations follows that of the perpendicular Alfvénic turbulence, in agreement with passive scalar theory. One puzzling result, however, is the scaling of the parallel magnetic field at small scales, which does not follow theoretical expectations. For the fi rst time, the technique used to measure the anisotropy of solar wind turbulence is applied to turbulence in reduced magnetohydrodynamic simulations. Again, the anisotropic scaling is seen, which is in agreement with critical balance predictions. It is also shown that when measuring the anisotropy with respect to the global, rather than local magnetic field, the anisotropic scaling cannot always be properly measured, which explains the previous apparently contradictory measurements in the literature.

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Turner, Andrew J. "Turbulence in the solar wind." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57960/.

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The solar wind provides a unique natural "laboratory" in which plasma turbulence may be investigated in-situ. Turbulence is statistically reproducible. Thus, in this thesis we investigate plasma turbulence in the solar wind through the statistical study of magnetic field observations. In particular, we investigate single-satellite time-series of the magnetic field. We discuss hydrodynamic turbulence, and make parallels between hydrodynamic and magnetohydrodynamic turbulence. In hydrodynamic turbulence a unique scaling relation may be determined from dimensional analysis. Importantly, one may not derive a unique scaling relation for magnetohydrodynamic turbulence from dimensional analysis. Therefore, comparison of observations and turbulence models are key to determining the underlying physics for specific plasma parameters. The inertial range is a range of scales over which energy cascades from large to small temporal-spatial scales. This thesis will predominantly be focused on the anisotropy and scaling of the inertial range within the solar wind. We investigate how sampling a solenoid field, i.e. . B = 0, with a single satellite produces an apparent nonaxisymmetry with respect to the background magnetic field. We also investigate how time-series discontinuities produced by non-turbulent structures alter the statistical analysis of various anisotropy measures. We will find that the commonly held picture of the solar wind, that specific temporal-spatial scales have a distinct physical origin, is an over simplified model. We will show that non-turbulent structures must be removed from the observations in order to analysis the statistics of the turbulence accurately. The work in this thesis helps to constrain theories of plasma turbulence where there is a background magnetic field with a greater magnitude than the root-mean-square magnitude of the turbulent fluctuations.

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Breech, Benjamin A. "Topics in solar wind turbulence." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 172 p, 2008. http://proquest.umi.com/pqdweb?did=1601519261&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Al-Mimar, Samer. "Integration of solar and wind power at Lillgrundwind farm. : Wind turbine shadow effect on solar farm atLillgrund wind farm." Thesis, Högskolan i Halmstad, Energivetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-28428.

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The supply of energy is a key factor in modern societies. As the old fossil sources for energy are dwindling, conflicts arise between competing nations and regions. Fossil energy sources also contribute to the pollution of the environment and emission of greenhouse gases. With renewable energy sources many of these drawbacks with fossil fuels can be eliminated as the energy will be readily available for all without cost or environmental impact. Combining the renewable energy sources will be very effective, particularly in commercial areas where lake of electricity is high. The cost of combining onshore wind and solar power plant is affordable. Furthermore there is no power failure or load shedding situation at any times. When it is manufactured in a large scale, cost of this integrated natural resources power generation system is affordable. Moreover there is no power failure or load shedding situation at any times. Therefore, it is the most reliable renewable power or electricity resources with less spending and highly effective production. ref [1]. The thesis work would take planning of offshore renewable plant (Lillgrund) with considering the resources of renewable power. The study would take in account combining the Lillgrund wind farm with solar system and take close look into the advantage and disadvantage of combining the renewable resources together and figure out if such station can work in proper way and provide sufficient power production. The study would take in account the effect of each resource on other resource, also calculations would be done. The study site is Lillgrund in south of Sweden. The Lillgrund wind farm is the most important offshore wind power plant installed in Sweden with a total capacity of 110 MW, corresponding to 48 turbines. ref [2].

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32

Moghadasiriseh, Amirhasan. "Analysis and Modeling of Advanced Power Control and Protection Requirements for Integrating Renewable Energy Sources in Smart Grid." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2469.

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Attempts to reduce greenhouse gas emissions are promising with the recent dramatic increase of installed renewable energy sources (RES) capacity. Integration of large intermittent renewable resources affects smart grid systems in several significant ways, such as transient and voltage stability, existing protection scheme, and power leveling and energy balancing. To protect the grid from threats related to these issues, utilities impose rigorous technical requirements, more importantly, focusing on fault ride through requirements and active/reactive power responses following disturbances. This dissertation is aimed at developing and verifying the advanced and algorithmic methods for specification of protection schemes, reactive power capability and power control requirements for interconnection of the RESs to the smart grid systems. The first findings of this dissertation verified that the integration of large RESs become more promising from the energy-saving, and downsizing perspective by introducing a resistive superconducting fault current limiter (SFCL) as a self-healing equipment. The proposed SFCL decreased the activation of the conventional control scheme for the wind power plant (WPP), such as dc braking chopper and fast pitch angle control systems, thereby increased the reliability of the system. A static synchronous compensator (STATCOM) has been proposed to assist with the uninterrupted operation of the doubly-fed induction generators (DFIGs)-based WTs during grid disturbances. The key motivation of this study was to design a new computational intelligence technique based on a multi-objective optimization problem (MOP), for the online coordinated reactive power control between the DFIG and the STATCOM in order to improve the low voltage ride-through (LVRT) capability of the WT during the fault, and to smooth low-frequency oscillations of the active power during the recovery. Furthermore, the application of a three-phase single-stage module-integrated converter (MIC) incorporated into a grid-tied photovoltaic (PV) system was investigated in this dissertation. A new current control scheme based on multivariable PI controller, with a faster dynamic and superior axis decoupling capability compared with the conventional PI control method, was developed and experimentally evaluated for three-phase PV MIC system. Finally, a study was conducted based on the framework of stochastic game theory to enable a power system to dynamically survive concurrent severe multi-failure events, before such failures turn into a full blown cascading failure. This effort provides reliable strategies in the form of insightful guidelines on how to deploy limited budgets for protecting critical components of the smart grid systems.

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Camporeale, Enrico. "Kinetic aspects of solar wind turbulence." Thesis, Queen Mary, University of London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509677.

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Jackman, Caitriona M. "Solar wind-magnetosphere coupling at Saturn." Thesis, University of Leicester, 2006. http://hdl.handle.net/2381/504.

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The studies contained within this thesis concern solar wind-magnetosphere coupling at Saturn. The first study uses data from the Cassini mission when it was upstream of Saturn to investigate the large-scale structure of the heliosphere and the interplanetary magnetic field (IMF) at 9 AU. The medium is found to be consistent with that expected during the declining phase of the solar cycle, structured by corotating interaction region (CIR) compressions and rarefactions. An empirical formula for open flux production at Saturn’s magnetopause is presented. Estimates of open flux production associated with a period of strong solar activity indicate that major magnetospheric dynamics were excited by reconnection-mediated solar wind interaction during the interval. The second study begins by examining concurrent IMF and Saturn kilometric radiation (SKR) data together with images from the Hubble Space Telescope from an interval in January of 2004, which show the effect of the arrival at Saturn of a CIR-related compression region. On examination of the IMF data surrounding the Saturn orbit insertion interval, it is suggested that a compression of similar character impinged on the magnetosphere at some point during the fly-through. Observations on the outbound pass show strong bursts of SKR extending to low frequencies, and provide evidence for the first specific link between SKR emission features and in situ dynamics inside Saturn’s magnetosphere. The third study comprises a theoretical model of the flows and currents in Saturn’s polar ionosphere under conditions of strong Dungey-cycle driving. The flow pattern consists of components which are intended to represent plasma sub-corotation in the middle magnetosphere region, and the Vasyliunas- and Dungey-cycles of convection at higher latitudes. The model results indicate a strong dawn-dusk asymmetry in Saturn’s main auroral oval under active Dungey-cycle conditions, and are in good agreement with observations.

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Daly, Noelle M. "Scintillation analysis of solar wind dynamics." Thesis, University of Glasgow, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301783.

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36

Graham, Georgina Alessandra. "The evolution of solar wind strahl." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10057348/.

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Suprathermal electrons are an important kinetic feature of the solar wind; however, their origin and evolution is yet to be fully understood. Suprathermal electrons are divided into two component populations: the field-aligned, beam-like 'strahl' and the approximately isotropic `halo'. Observations have revealed that the strahl component cannot be subject solely to expansion effects as it travels away from the Sun along the interplanetary magnetic field (IMF). Thus, strahl scattering processes must occur within the solar wind and may be at least partly responsible for the existence of the isotopic halo. In this thesis, strahl evolution is examined, in order to constrain the possible strahl scattering mechanisms and investigate strahl utility as an IMF probe. Novel analysis methods are applied to strahl observations to obtain the largest radial range of strahl width observations to date; examine the effect of distance travelled along the IMF on strahl width; and provide estimates of IMF orientation. It is found that strahl scattering likely occurs throughout the solar wind, to at least to 5.5 AU, and strahl electrons are most likely scattered to form part of the halo population by 9 AU. It is also concluded that strahl scattering occurs quasi-continuously and results indicate that scattering may be more intense closer to the Sun, particularly for higher energy electrons. The increase in strahl beam-width with distance is also greater for higher energy strahl, suggesting that there is a dominant scattering mechanism with an inherent energy relation, most likely explained by resonant wave-particle interactions. Finally, observing relatively narrow strahl beams at 1 AU using high resolution Cluster data allowed estimations of strahl width that generally lie within 20° of the magnetometer observations.

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Seeluangsawat, Paisa 1980. "Magnetic holes in the solar wind." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/8536.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2002.
Includes bibliographical references (p. 41).
We attempt to locate magnetic holes from several years of data collected from WIND and ACE spacecraft and use them to study some statistical properties of the magnetic holes.
by Paisa Seeluangsawat.
S.B.

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38

Marino, Raffaele. "Scaling laws in solar wind turbulence." Nice, 2009. http://www.theses.fr/2009NICE4104.

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Dans ma thèse de doctorat, je dérive la loi de Yaglom pour la magnétohydrodynamique, une relation de proportionnalité entre le moment mixte d’ordre 3 des incréments longitudinaux des variables d’Elsässer et l’échelle de ces incréments. En utilisant des mesures de la sonde spatiale Ulysses, j’ai montré pour la première fois la validité de cette relation, démontrant ainsi l’existence d’une cascade turbulente d’énergie et la nature turbulente des fluctuations de vitesse et champ magnétique dans les plasmas magnétisés. La relation de Yaglom pour la MHD permet aussi la première estimation directe des taux de transfert de pseudo-énergies turbulentes dans le vent solaire, et je l’ai utilisée pour montrer que la dissipation en fin de cascade turbulente MHD peut contribuer de 8% à 15% du taux de chauffage du vent solaire dans le cas incompressible, et jusqu’à 100% dans certains cas. Une analyse du vent solaire dans l’écliptique mesuré par Ulysses montre que le vent rapide a les mêmes propriétés sur l’écliptique et aux pôles, alors que le vent lent présente un taux de transfert bien plus élevé. J’ai également étudié le rôle des fluctuations de densité en turbulence MHD dans le vent solaire et j’ai montré qu’une relation phénoménologique similaire à la loi de Yaglom est vérifiée, ce qui implique que les fluctuations de densité ont un effet important et peuvent amplifier le taux de transfert d’énergie vers les petites échelles, ce qui permet un chauffage turbulent plus important et un refroidissement plus lent du vent solaire au cours de son expansion dans l’espace interplanétaire
In my PhD thesis I re-derive the Yaglom law for the MHD, a proportionality relation between the mixed third-order moment of the longitudinal increments of the Elsässer fields and the increment scale. Using Ulysses spacecraft measurements, I evidenced for the first time the existence of this relation in the polar solar wind, proving the presence of a local energy cascade and the turbulent character of the field fluctuations in Alfvénic plasmas. The observation of the Yaglom law for MHD also permits the first direct estimation of pseudo-energy dissipation rates in solar wind turbulence. In the thesis I also explored the possibility that the dissipation of energy occurring at the end of a turbulent MHD cascade can be responsible for the solar wind heating. I found that incompressible turbulent cascade can contribute to the solar wind in situ heating from 8 % to 50 % on average, and up to 100 % in some cases. Analysis of the ecliptic wind measured by Ulysses show that while the fast ecliptic streams have similar properties as the polar fast wind, the slow streams show an highly enhanced energy transport. I also study the role of large scale solar wind density fluctuations in MHD turbulence and showed that a phenomenological compressible Yaglom-like relation is verified within the solar wind, indicating that compressible effects are an important ingredient of the turbulent cascade and permit the transfer of a considerably larger amount of energy toward the small scales, where it can be dissipated to heat the plasma and slow down the radial cooling of the wind as observed in interplanetary space

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Woolsey, Lauren. "Magnetic Influences on the Solar Wind." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493537.

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The steady, supersonic outflow from the Sun we call the solar wind was first posited in the 1950s and initial theories rightly linked the acceleration of the wind to the existence of the million-degree solar corona. Still today, the wind acceleration mechanisms and the coronal heating processes remain unsolved challenges in solar physics. In this work, I seek to answer a portion of the mystery by focusing on a particular acceleration process: Alfven waves launched by the motion of magnetic field footpoints in the photosphere. The entire corona is threaded with magnetic loops and flux tubes that open up into the heliosphere. I have sought a better understanding of the role these magnetic fields play in determining solar wind properties in open flux tubes. After an introduction of relevant material, I discuss my parameter study of magnetic field profiles and the statistical understanding we can draw from the resulting steady-state wind. In the chapter following, I describe how I extended this work to consider time dependence in the turbulent heating by Alfven waves in three dimensional simulations. The bursty nature of this heating led to a natural next step that expands my work to include not only the theoretical, but also a project to analyze observations of small network jets in the chromosphere and transition region, and the underlying photospheric magnetic field that forms thresholds in jet production. In summary, this work takes a broad look at the extent to which Alfven-wave-driven turbulent heating can explain measured solar wind properties and other observed phenomena.
Astronomy

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40

Tasnim, Samira. "Generalized Theory of the Solar Wind." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/16755.

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Development of a self-consistent theoretical model is of fundamental importance to the study of the solar wind. Such a model is necessary to understand the origin of the solar wind as well as observational and theoretical aspects. For instance, a complete description of the acceleration of solar wind particles, intrinsic velocity and magnetic field components, role of magnetic field in the solar wind's angular momentum loss, and so on has not yet been achieved. This thesis presents two data-driven solar wind models to provide more detailed pictures of the solar wind in the equatorial plane, to extract the solar wind plasma quantities from the direct observations at 1 AU, and to describe the underlying physics. It also provides a comprehensive comparison between analytic predictions, observations, and advanced MHD (magnetohydrodynamics) simulation outputs. Chapter 1 provides a short literature review and a brief introduction for the thesis. Chapter 2 develops an analytic, self-consistent, theoretical model for the solar wind that includes conservation of angular momentum, frozen-in magnetic fields, and radial (r) and azimuthal (φ) components of velocity and magnetic field from the source surface/inner boundary to 1 AU. The solar wind model enforces corotation at the source surface (rs) assumes a constant radial speed at all heliolongitude, and applies near the equatorial plane. This model generalises previous models and reproduces the previous models in the appropriate limits. The model calculates the Alfvénic critical radius (ra) using the radial Alfvénic Mach number at 1 AU, and the predicted values agree with some recent observations. The predicted azimuthal velocity, which is only due to corotation is in the sense of corotation, but varies with, heliolongitudes (φ). Observations of the azimuthal velocity at 1 AU are usually much larger than predictions and not always in the corotation direction. These azimuthal velocities can not be explained by conservation of angular momentum alone. The standard interpretation involving stream-stream interactions and dynamical behaviour seems reasonable. Chapter 3 develops an accelerating solar wind model that includes the following: conservation of angular momentum, deviations from corotation, and non-radial velocity and magnetic field components from an inner boundary (or source surface) to beyond 1 AU. The model includes an accelerating solar wind profile using a solution of the time-steady isothermal equation of motion and predicts locations ra for the Alfvénic critical point which agree with recent observations. This model allows the flow velocity v to not always be parallel to magnetic field B in the corotating frame with the Sun, which results an electric field (E′) in the corotation frame. The resulting (E′ × B) drift may lead to enhanced scattering/heating of sufficiently energetic particles. The model demonstrates the existence of non-zero deviations δvφ from corotation at the source surface. These deviations of corotation are analogous to the transverse velocities caused by granulation and supergranulation motions. The abrupt changes in δvφ(rs,φs) are interpreted in terms of converging and diverging flows at the granulation cell boundaries and centers, respectively. Large range of variations of the angular momentum predicted and then are interpreted in terms of an intrinsic source in the solar wind of vorticity and turbulence from near the Sun towards 1 AU and beyond. Chapter 4 presents a comprehensive comparison where the accelerating solar wind model's predictions, observations are compared qualitatively and quantitatively with Block-Adaptive-Tree-Solarwind-Roe-Upwind-Scheme (BATS-R-US) simulation's outputs for the solar rotation period from November 21 to December 17, 2013. The chapter compares simulation outputs in the ecliptic plane with the analytic model results in the equatorial plane. Comparisons between simulated plasma quantities for long run time and short run time demonstrate that the initial solar wind plasma is entirely swept out by the simulated wind. It appears that high order grid refinement helps the simulation to reach a steady-state MHD system. The current version of the BATS-R-US simulation code treats the solar corona (SC) and the inner heliosphere (IH) separately and discontinuities in simulation outputs remain in the intersection of two modules. Overall, the simulated magnetic fields agree quite well with model predictions, much better than the density, velocity, and temperature. Radial profiles of plasma quantities have some qualitative agreement along a plasma flux tube, but quantitative differences are apparent. Chapter 5 summarizes the results in this thesis and discusses future avenues for research.

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Montagud, Camps Victor. "Turbulent dynamics of the solar wind." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS373/document.

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Le but de cette thèse est l'étude du développement de la turbulence dans le vent solaire entre 0.2 et 1 unité astronomique (UA) du soleil (i.e. l'orbite terrestre). L'étude est faite en résolvant numériquement les équations de la MHD après soustraction de l'écoulement moyen radial. Les deux aspects de la turbulence qui nous intéressent sont la structure 3D des spectres d’énergie et le chauffage du plasma qui résulte de la dissipation turbulente des tourbillons et couches de courant emportés par le vent. On cherche à déterminer quelles sont les conditions du plasma près du soleil qui permettent d’aboutir à ce qu'on observe à 1 UA. Un but important de mon travail est aussi de déterminer si la physique qui est présente dans les équations que j'intègre (la MHD) suffit pour arriver à reproduire ce qu'on a déjà observé dans cet intervalle de distance. Nous introduisons le contexte de notre travail dans la première partie. On y trouve les équations de base, une introduction à la turbulence, un résumé sur la physique du vent solaire et de la couronne solaire. La partie 2 sera consacrée à l'étude de l'anisotropie de la cascade turbulente, et plus précisément du spectre 3D. Dans la zone inertielle, les mesures in-situ vers 1 UA montrent des figures complexes pour ces spectres qu'on peut interpréter de plusieurs façons : nos simulations numériques permettent de lever toute ambiguïté. Plus précisément, la question est de savoir quand intervient l'axe soleil-terre, et quand intervient l'axe du champ magnétique moyen. La partie trois est centrée sur le chauffage turbulent dans les vents rapides et lents. Entre 0.3 et 1 UA, la température des protons diminue anormalement lentement, ce qui indique une source de chauffage, qu'on suppose ici être la dissipation des tourbillons et couches de courant emportés par le vent. Pour démontrer que cette hypothèse est raisonnable, nous considérons d’abord le modèle de Burgers qui est un modèle pour l'évolution d’ondes sonores. Ensuite, nous passons à l'étude du cas plus complexe d'un volume de plasma 3D. Nous examinerons les conditions initiales correspondant aux vents lents et rapides. Dans les deux cas, on adoptera des anisotropies spectrales différentes. Dans la dernière partie, nous exposerons les conclusions de notre travail et proposerons d'introduire l'anisotropie de la température dans un travail futur
The aim of this thesis is the study of the development of turbulence in the solar wind between 0.2 and 1 astronomical unit (AU) from the Sun (i.e. Earth’s orbit). The study is done by solving the magnetohydrodynamics equations (MHD) after subtracting the mean radial flow. The two aspects of turbulence that interest us are the 3D structure of the energy spectra and the heating of plasma that results from the turbulent dissipation of eddies and current layers transported by the wind. We want to determine which conditions of the plasma close to the Sun can result into what we observe at 1 AU. We have relatively detailed measurements of what happens between 0.3 and 1 AU. One important goal of this work is to determine if the physics present in the equations that are integrated (MHD) is sufficient to reproduce what is observed in this interval of distances. We introduce the context of our work in the first part. We give a summary of the physics concerning the solar wind and the solar corona, and the basic equations used to describe the solar wind plasma and an introduction to turbulence. Part 2 is dedicated to the study of anisotropy in the turbulent cascade, which characterizes 3D spectra. In the inertial range, in-situ measurements at 1 AU show complex figures for these spectra that we can interpret in several ways : numerical simulations allow to clear ambiguities. An important question is to know whether the Earth-Sun symmetry axis or the mean magnetic field axis is dominant.The third part focuses on turbulent heating in fast and slow winds. Between 0.3 and 1 AU, proton temperature decreases more slowly than expected, which requires a heating source. This source is supposed to be the continuous dissipation of eddies and current layers transported by the wind. To start with, we consider the simple case of Burgers equation, which is a one-dimensional model for shock formation. Thereupon, we switch to the 3-dimensional case, where we consider initial conditions appropriate for slow and fast winds. In the last part we expose our conclusions and propose the implementation of temperature anisotropy as future work

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Sundberg, Torbjörn. "New Perspectives on Solar Wind-Magnetosphere Coupling." Doctoral thesis, KTH, Rymd- och plasmafysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32070.

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The streaming plasma in the solar wind is a never ending source of energy, plasma, and momentum for planetary magnetospheres, and it continuously drives large-scale plasma convection systems in our magnetosphere and over our polar ionosphere. This coupling between the solar wind and the magnetosphere is primarily explained by two different processes: magnetic reconnection at high latitudes, which interconnects the interplanetary magnetic field (IMF) with the planetary dipole field, and low-latitude dynamos such as viscous interaction, where the streaming plasma in the solar wind may trigger waves and instabilities at the flanks of the magnetosphere, and thereby allow solar wind plasma to enter into the system.This work aims to further determine the nature and properties of these driving dynamos, both by statistical studies of their relative importance for ionospheric convection at Earth, and by assessment and analysis of the Kelvin-Helmholtz instability at Mercury, utilizing data from the MESSENGER spacecraft's first and third flyby of the planet.It is shown that the presence of the low-latitude dynamos is primarily dependent on the IMF direction: the driving is close to non-existent when the IMF is southward, but increases to the order of a third of the total ionospheric driving when the IMF turns northward (here, the magnitude of the driving is also shown to be dependent on the viscous parameters in the solar wind). The work also discusses the saturation of the reconnection generated potential, and shows that the terrestrial response follows a non-linear behavior for strong solar wind driving both when the IMF is southward and northward.Comparative studies of different magnetospheres provide an excellent path for increasing our understanding of space-related phenomena. Here, study of the Kelvin-Helmholtz instability at Mercury allows us to investigate how the different parameters of the system affect the mass, energy, and momentum transfer at the flanks of the magnetosphere. The large ion gyro radius expected is shown to develop a dawn-dusk asymmetry in the growth rates, with the dawn side as the more unstable of the two. This effect should be particularly visible when the planet is close to perihelion. Mercury's smaller scale size combined with the relatively high spacecraft velocity is also shown to provide excellent opportunities for studying the spatial structure of the waves, and a vortex reconstruction that can explain all the large-scale variations in the Kelvin-Helmholtz waves observed during MESSENGER's third Mercury flyby is presented.
QC 20110405

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Sundberg, Torbjörn. "Magnetospheric oscillations due to solar wind perturbations." Thesis, KTH, Rymd- och plasmafysik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91541.

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Westerberg, Lars-Göran. "Solar wind interaction with the terrestrial magnetopause." Doctoral thesis, Luleå tekniska universitet, Strömningslära och experimentell mekanik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26691.

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The solar wind interaction with the terrestrial magnetosphere is a source for many spectacular phenomena on or close the Earth's surface. A key question during the last fifty years have been how the solar wind plasma can enter the terrestrial magnetic shield represented by the magnetosphere and its outermost layer called the magnetopause. This have been the seed for many controversies among researchers throughout the years. Today we know that there are several possibilities for the solar wind to break through the magnetic boundary of the Earth. The main plasma transport mechanism at the magnetopause is called magnetic reconnection, where the magnetic energy stored in the solar wind is converted to kinetic energy through a localized break-down of the ideal frozen-in condition of the magnetic field within the plasma. Since its introduction to the space-physical community in the late 1950's, reconnection research have had its primary focus on understanding the onset mechanisms inside the diffusion region where the solar wind magnetic field is reconnected with the magnetospheric magnetic field. In this thesis work we put the context well out of the diffusion region and focuses on the implications of magnetic reconnection onto the surrounding solar wind plasma, rather than on the main mechanisms which initiates the process. We present solutions for the structure of the plasma flow through the magnetopause surface during conditions of ongoing reconnection. This is done through viscous-resistive reconnection models together with models where finite gyro-radius effects are considered. In order to validate the viscous-resistive model we also couple the analytical solutions with \textit{in situ} measurements made by the Cluster spacecraft fleet. This results in an entirely new way of determining the magnetopause transition layer thickness and the location of the reconnection site from spacecraft data.
Godkänd; 2007; 20070904 (pafi)

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Westerberg, Lars G. "Solar wind interaction with the terrestrial magnetopause /." Luleå : Luleå University of Technology, 2005. http://epubl.luth.se/1402-1757/2005/31.

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Hanlon, Paul Gareth. "Solar wind influences within the Jovian magnetosphere." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415090.

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Longden, Nicola Claire. "Global precipitation effects following solar wind drivers." Thesis, Lancaster University, 2007. http://eprints.lancs.ac.uk/9387/.

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Hijazin, Maher Ibrahim. "Solar & wind driven reciprocating lift pumps." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332826.

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Barata, Johann. "Evaluation of Wind Loads on Solar Panels." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/567.

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The current impetus for alternative energy sources is increasing the demand for solar energy technologies in Florida – the Sunshine State. Florida’s energy production from solar, thermal or photovoltaic sources accounts for only 0.005% of the state total energy generation. The existing types of technologies, methods of installation, and mounting locations for solar panels vary significantly, and are consequently affected by wind loads in different ways. The fact that Florida is frequently under hurricane risk and the lack of information related with design wind loads on solar panels result in a limited use of solar panels for generating energy in the “Sunshine State” Florida. By using Boundary Layer Wind Tunnel testing techniques, the present study evaluates the effects of wind on solar panels, and provides explicit and reliable information on design wind loads in the form of pressure coefficient value. The study considered two different types of solar panel arrangements, (1) isolated solar panel and (2) arrays, and two different mounting locations, (1) ground mounted and (2) roof mounted. Detailed wind load information was produced as part of this study for isolated and arrayed solar panels. Two main conclusions from this study are the following:(1) for isolated solar panel with high slopes the wind load for wind angle of attack (AoA) perpendicular to the main axis exhibited the largest wind loads; (2) for arrays, while the outer rows and column were subjected to high wind loads for AoA perpendicular to the main axis, the interior solar panels were subjected to higher loads for oblique AoA.

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Westerberg, Lars-Göran. "Solar wind interaction with the terrestrial magnetopause." Licentiate thesis, Luleå tekniska universitet, Strömningslära och experimentell mekanik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17955.

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Magnetic reconnection plays an important role in the transfer of mass, energy and momentum from the solar wind to the terrestrial magnetosphere. The earliest contributions to the theory of magnetic reconnection dates from the beginning of the 1930's. However, it took until the end of the 1950's when Sweet and Parker made their first reconnection model, for the concept to reach a somewhat solid ground. During the years since then magnetic reconnection has walked through the phase of reaching mythical proportions where some researchers believed in it, and some not, to the acceptance it has today where the main issue not is whether the process happens or not, but rather the main physical properties and the implications of it. During the last fifteen years much of the research due to the rapid increase in computer capacity, treats numerical simulations of magnetic reconnection. Theoretical analysis keeps though its position as a cornerstone for the understanding of the process. But also for the base of new implemented models. Much of the theoretical work accomplished to this day has its focus on magnetic reconnection itself; applications for different conditions, and the onset of the process - something which still is under much discussion among researchers. This work focuses on the implications of magnetic reconnection in combination with the outer magnetosheath flow. The analysis treats a two-dimensional and three-dimensional case. For the 3D case, the magnetosheath plasma flow is considered to be incompressible, while we for the 2D case also treat a compressible magnetosheath plasma. Magnetic reconnection is assumed to occur in a region stretching from the sub-solar point to the north, at an arbitrary point for the 2D case, and along a line parallel to the y-axis for the 3D case. The analysis is based on the MHD equations including dissipative effects such as viscosity and resistivity, where the equations are solved approximately by the use of an ordinary perturbation expansion for large Reynolds and Lundqvist numbers. The objective of the 2D study treating an incompressible plasma flow, is to get a description of the current transition layer in combination with the outer magnetosheath and boundary layer flow. The solutions are asymptotically matched with an existing model for the magnetosheath magnetic field. For the 2D compressible case and 3D analysis, the objective is to study the development of the magnetic field and total velocity during the transition from the magnetosheath to the magnetosphere.
Godkänd; 2005; 20070116 (ysko)

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Dissertations / Theses on the topic 'Wind and solar generations'

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