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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The design and development of an augmented vertical axis wind turbine

Mewburn-Crook, Anthony January 1990 (has links)
The augmented vertical axis wind turbine resulted from a survey of the problems of existing wind turbines, and the identification of the design criteria that it should be inherently safe and reliable. It should be self-starting in low winds and continue to run in high Winds, and it should be environmentally acceptable. The design consisted of a vertical axis rotor, with five vertical and five horizontal blades, surrounded by an augmentor which contained eight converging stators and a dome desigried to increase the flow rate through the rotor, and to decrease the pressure at exit from the rotor. Extensive model tests showed that the wind turbine had attractive operating characteristics, which were confirmed by a prototype machine with a 6m diameter rotor rated at 10kW. However, a detailed analysis of the design and costs showed that it was too expensive. An analysis of an idealised augmented vertical axis wind turbine showed that there was potential for increasing the performance and decreasing costs. Measurements of the detailed flow field through the rotor and around the augmentor demonstrated that augmentation was by means of an increased pressure drop across the rotor, combined with an increased mass flow rate through it. The efficiency of the upstream part of the rotor was also increased by the augmentor. The benefits of turbulent mixing in the wake of the turbine between the external flowfield and the flow through the turbine were also recognised. Major modifications to the design of the augmentor and rotor resulted in two types of wind turbine which maintained the attractive operating characteristics and appeared to be commercially viable. The designs offer particular benefits in terms of inherent safety and reliability. The potential of cost effective, large multi¬megawatt machines is also recognised. The work has also provided further insight into wind turbine augmentation, and in the design and development of vertical axis rotors.
42

Load management for wind-driven AC generator

Rehman, Mian Hafeez January 2010 (has links)
Typescript, etc. / Digitized by Kansas Correctional Industries
43

The emergence of innovation systems in new locations : theoretical explorations and an in-depth case study of wind energy technologies in Ireland, 1990-2014

O'Donovan, Cian January 2016 (has links)
This thesis is about the processes of creating renewable electricity systems in new locations. Specifically it addresses the challenges and drivers of building-up renewable energy system in a `fast follower' country, Ireland. With increasing scientific, political, civil society and private sector agreement on the need to reduce green-house gas emissions from the provision of electricity, the rolling out of complex, renewable electricity systems from countries in which initial system building activities have taken place to others is an important issue. The primary research question posed is `what explains the growth of the wind electricity system in Ireland?' This question is reflected upon by asking `what does the Irish experience tell us about why and how these systems spread to new locations?' The thesis addresses an innovation studies audience, making a theoretical contribution to the field of sustainability transitions. It contributes to recent research integrating theories from human geography by offering new insights on how location influences building of large scale renewable electricity systems in new jurisdictions. It contributes findings about the rapid development of the Irish wind system that challenge two dominant perspectives; roll-out in Ireland has been driven by EU policy push and the development of the industry is fundamentally about the extent of national subsidies. We find both perspectives are partial; what they omit is likely to be essential to reproducing the Irish experience. This thesis takes as its unit of analysis the wind energy system itself, and using a `technological innovation system' framework, examines and evaluates the structure of the system; the complex arrangement of institutions, actors and technologies; and the dynamic innovation processes or `functions' of the system. An inquiry into the substantive historical contexts of the development of the system make possible insights into the locational characteristics and relations within and between the system; drivers, barriers and influences of direction of the system processes; and the contexts in which decisions are made and technological change takes place. The thesis finds the development of a renewable electricity system in new locations is simultaneously heavily influenced by transnational dimensions of system actors relations and institutions, and shows that while the direction of the emergent technological pathway is influenced at multiple spatial and governance levels, legitimation of the technology is highly localised.
44

Sail aerofoil applied to a vertical-axis wind turbine

Robert, Jean. January 1977 (has links)
No description available.
45

Wind power in Brazil

Elin, Karlsson January 2009 (has links)
<p>As welfare and industry production gets higher the demand for electricity increases. Almost 90 % of the electricity generated in Brazil is from renewable sources, 85 % of the renewable energy comes from hydropower. Even if Latin America has a lot of potential for wind power their installed capacity in only 1 % of the worlds total installed capacity. Lately more and more wind turbines and wind farms are appearing along Brazil’s over 7500 kilometer long coastline.</p><p>Osorio wind farm is the largest wind farm in Latin America with a total installed effect of 150 MW. In the same state, Rio Grande du Sul, a farmer has shown interest for using his property for wind power. The purpose of this project is to lay the foundation for a deeper investigation about using Aguapé farm’s property for wind power and to show the future possibilities for Brazilian wind power.</p><p>The study is made on set in Brazil, divided into two parts, one theoretical research part and one practical part with a field trip to Aguapé farm.</p><p>In 2002 The Brazilian Government launched the PROINFA program, Alternative Sources for Energy Incentive. This year, 2009, the first wind power projects auctions are held to increase the generation from renewable electricity sources. Wind power in Brazil has the highest production when the level in the hydropower dams are at the lowest, which by integrating the electrical generating wiht wind power makes it possible to save water and avoiding lack of electricity.</p><p>Aguapé farm is located between one of the worlds biggest fresh water lakes, Lagao dos Patos, and the Atlantic Ocean. The location has very good wind potential, almost like offshore because of the closeness to large areas of water. Road connections to the farm are functional in good and dry weather conditions and not far away a 138kV power line passes through. </p><p>Surrounding neighbors are positive to wind power which makes it easier with problem caused by wind turbines, for example noise. About 40 kilometers from the farm Lagoa do Peixe National Park is located. Suggestion from the Aguapé owner is to stop with the rice production, which is disturbing the park’s natural hydrological system, to use the property for wind turbines instead.</p><p>Conclusions of the study shows that the potential for wind power at Aguapé farm is excellent and that wind power at Aguapé farm will help both the owner, Lagoa do Peixe National Park and Brazil to a better future.</p>
46

Theoretical analysis of the performance of a small wind energy converter

Winberg, Helena, Tiestö, Micaela January 2008 (has links)
<h1>Abstract</h1><p>This thesis has been done in Barcelona, Spain, in cooperation with the University of Gävle (HiG) and the Universitat Politècnica de Catalunya (UPC). At UPC there is a project carried out where the goal is to analyze the characteristics and performance of the wind turbine IT-100, with an intention to optimize it. This is carried out by assignment of Engineers Without Borders and Practical Action. The purpose of the thesis has been to present what power, value of tension and current the turbine will produce in different wind velocities.</p><p> </p><p>The IT-100 is built to generate electricity to the population in the countryside in, among other countries, Peru. The energy the turbine captures from the wind will be used to charge vehicle batteries that are used in the households as a source of electricity. This is an effective, cheap and environmental-friendly way of supplying households with electricity.</p><p> </p><p>The idea of using the energy in the wind has been known for thousands of years. It started with simple windmills for grinding grain and later more complicated machines like wind turbines were created. Wind power is one of the worlds cleanest sources of energy with as good as no emissions at all while in running.</p><p> </p><p>The result of the work with this thesis work is an Excel file where the, by the purpose requested, parameters are presented in relation to different wind velocities. With some conditions set from the start, some known values of reference and the rotor blades rotational speed as a key variable, these parameters were possible to calculate.</p><p> </p><p>During the work, the project came upon some difficulties such as; not enough information about the wind turbine, too little previous knowledge among the students and trouble with the Spanish language. However, on the whole the project has been successful and a good learning experience.</p>
47

Winds of change : renewable energy and the location of wind turbines in Prince Edward County, Ontario /

Lopes, Sandra L. January 2004 (has links)
Thesis (M.A.)--York University, 2004. Graduate Programme in Geography. / Typescript. Includes bibliographical references (leaves 170-178). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL:http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss&rft%5Fval%5Ffmt=info:ofi/fmt:kev:mtx:dissertation&rft%5Fdat=xri:pqdiss:MQ99350
48

Wind power capacity credit evaluation using analytical methods

Mishra, Sunanda 19 August 2010
Wind power is the most mature green energy source in electric power systems and is now a booming worldwide industry. The use of wind power is growing rapidly throughout the world to reduce environmental degradation. Due to global environmental concerns and public awareness, many power utilities around the world are considering wind energy as a substitute for conventional generation. Many governments already have energy plans and policies in place to ensure significantincrease in power generation using wind energy within designated time periods. The wind is variable, site specific and is an intermittent source of energy. It is therefore a complex task to analyze generating system capacity adequacy considering wind energy. The growing application of wind power dictates the need to develop methods to evaluate the system reliability and the capacity value of wind power. Wind is generally considered to be a source of energy, rather than a power source. It is equally important however, to consider the capacity credit of wind power as its penetration increases in electric power systems. It is very important for both electric power utilities and wind power developers to accurately assess wind capacity credit and therefore it is necessary to study and develop different methodologies for performing this task. The research presented in this thesis examines a range of methods used for the evaluation of wind capacity credit using data from four wind sites in Saskatchewan. The techniques, methods and results presented in this thesis should prove to be valuable for system planners assessing generating capacity adequacy evaluation incorporating wind energy.
49

Theoretical analysis of the performance of a small wind energy converter

Winberg, Helena, Tiestö, Micaela January 2008 (has links)
Abstract This thesis has been done in Barcelona, Spain, in cooperation with the University of Gävle (HiG) and the Universitat Politècnica de Catalunya (UPC). At UPC there is a project carried out where the goal is to analyze the characteristics and performance of the wind turbine IT-100, with an intention to optimize it. This is carried out by assignment of Engineers Without Borders and Practical Action. The purpose of the thesis has been to present what power, value of tension and current the turbine will produce in different wind velocities.   The IT-100 is built to generate electricity to the population in the countryside in, among other countries, Peru. The energy the turbine captures from the wind will be used to charge vehicle batteries that are used in the households as a source of electricity. This is an effective, cheap and environmental-friendly way of supplying households with electricity.   The idea of using the energy in the wind has been known for thousands of years. It started with simple windmills for grinding grain and later more complicated machines like wind turbines were created. Wind power is one of the worlds cleanest sources of energy with as good as no emissions at all while in running.   The result of the work with this thesis work is an Excel file where the, by the purpose requested, parameters are presented in relation to different wind velocities. With some conditions set from the start, some known values of reference and the rotor blades rotational speed as a key variable, these parameters were possible to calculate.   During the work, the project came upon some difficulties such as; not enough information about the wind turbine, too little previous knowledge among the students and trouble with the Spanish language. However, on the whole the project has been successful and a good learning experience.
50

Wind power in Brazil

Elin, Karlsson January 2009 (has links)
As welfare and industry production gets higher the demand for electricity increases. Almost 90 % of the electricity generated in Brazil is from renewable sources, 85 % of the renewable energy comes from hydropower. Even if Latin America has a lot of potential for wind power their installed capacity in only 1 % of the worlds total installed capacity. Lately more and more wind turbines and wind farms are appearing along Brazil’s over 7500 kilometer long coastline. Osorio wind farm is the largest wind farm in Latin America with a total installed effect of 150 MW. In the same state, Rio Grande du Sul, a farmer has shown interest for using his property for wind power. The purpose of this project is to lay the foundation for a deeper investigation about using Aguapé farm’s property for wind power and to show the future possibilities for Brazilian wind power. The study is made on set in Brazil, divided into two parts, one theoretical research part and one practical part with a field trip to Aguapé farm. In 2002 The Brazilian Government launched the PROINFA program, Alternative Sources for Energy Incentive. This year, 2009, the first wind power projects auctions are held to increase the generation from renewable electricity sources. Wind power in Brazil has the highest production when the level in the hydropower dams are at the lowest, which by integrating the electrical generating wiht wind power makes it possible to save water and avoiding lack of electricity. Aguapé farm is located between one of the worlds biggest fresh water lakes, Lagao dos Patos, and the Atlantic Ocean. The location has very good wind potential, almost like offshore because of the closeness to large areas of water. Road connections to the farm are functional in good and dry weather conditions and not far away a 138kV power line passes through. Surrounding neighbors are positive to wind power which makes it easier with problem caused by wind turbines, for example noise. About 40 kilometers from the farm Lagoa do Peixe National Park is located. Suggestion from the Aguapé owner is to stop with the rice production, which is disturbing the park’s natural hydrological system, to use the property for wind turbines instead. Conclusions of the study shows that the potential for wind power at Aguapé farm is excellent and that wind power at Aguapé farm will help both the owner, Lagoa do Peixe National Park and Brazil to a better future.

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