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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.
81

And Then They Lived Sustainably Ever After? : Experiences from Rural Electrification in Tanzania, Zambia and Kenya

Ilskog, Elisabeth January 2008 (has links)
Accelerating the introduction of basic, clean energy services is seen as a key strategy for promoting sustainable development in rural areas. Still, many people worldwide lack access to modern energy such as electricity, and Africa lags behind other developing regions of the world. Support to rural electrification is therefore given high priority by the national governments and donor organisations. There is a trend to encourage the involvement of other actors than national utilities for implementation of rural electrification. At the same time, it is required that the activities shall contribute to sustainable development. The objective of the work presented in this thesis has been to reach increased knowledge on the impact from organisational factors on project sustainability, and to examine whether rural electrification implemented by private entrepreneurs or other non-governmental organisations contribute more effectively to sustainable development than the conventional approach where rural electrification is the responsibility of a government utility. A key activity of the research work has been to improve and develop the present methodologies used for evaluations, as to attain a more functional in-field evaluation method. The thesis presents findings from seven rural electrification cases in Eastern and Southern Africa and shows how these can be used to illustrate different dimensions of sustainability by means of indicators. The evaluation indicates that the national utilities perform better from a social/ethical perspective, whereas the private organisations and the community-based organisations manage their client-relation issues in a more sustainable way. In addition, a literature survey shows that among stakeholders there are a number of “concepts-taken-for-granted” as regards to rural electrification. These are not supported by the findings from the seven cases. The observed deviations between expectations and realities can obstruct the development as decision-makers may have unrealistic expectations when planning for new electrification activities. Instead, activities have to be implemented with the empirical reality in mind. By doing so the ambiguities, complexities and all the paradoxes of rural electrification can hopefully be better managed. The study has been funded by The Swedish International Development Agency, Department for Research Cooperation (SAREC), and Ångpanneföreningen’s Foundation for Research and Development (ÅFORSK). / QC 20100812
82

Organically Grown Microgrids: the Development and Simulation of a Solar Home System-based Microgrid

Unger, Kurtis January 2012 (has links)
The United Nations has declared 2012 the ``International Year of Sustainable Energy for All''. A substantial portion of the world's population (some 1.3 billion people) currently live without electricity and development efforts to reach them are progressing relatively slowly. This thesis follows the development of a technology which can enable community owned and operated microgrids to emerge based solely on the local supply and demand of that community. Although this thesis ends with the technical analysis of a DC/DC converter, there is a significant amount of background to cover in order to properly understand the context in which it will be used. After providing an introduction into typical rural electrification efforts and pointing out some of the shortcomings of these projects, this thesis introduces some cutting edge efforts which combine solar home system technology with cellular technology and discusses the benefits of such a marriage of technology. Next, the research proposes some tweaks to this novel technology and provides a high-level economic demonstration of the spread of solar home systems in a community based on these modifications. It then takes this concept even further and proposes the addition of a DC/DC converter which could turn these individual solar home systems into a proper microgrid. This thesis elaborates on the development process of simulating such a microgrid in PSCAD, including the individual components of a solar home system and the specific task of designing the converter which would form the backbone of the proposed microgrid. The final simulations and analyses demonstrate a microgrid that is both technically and economically feasible for developing world applications.
83

Unfulfilled promise electrification and the Chicago, Milwaukee & St. Paul Railroad /

Michalski, Adam T. January 2009 (has links)
Title from title page of PDF (University of Missouri--St. Louis, viewed March 1, 2010). Includes bibliographical references (p. 110-117).
84

Organically Grown Microgrids: the Development and Simulation of a Solar Home System-based Microgrid

Unger, Kurtis January 2012 (has links)
The United Nations has declared 2012 the ``International Year of Sustainable Energy for All''. A substantial portion of the world's population (some 1.3 billion people) currently live without electricity and development efforts to reach them are progressing relatively slowly. This thesis follows the development of a technology which can enable community owned and operated microgrids to emerge based solely on the local supply and demand of that community. Although this thesis ends with the technical analysis of a DC/DC converter, there is a significant amount of background to cover in order to properly understand the context in which it will be used. After providing an introduction into typical rural electrification efforts and pointing out some of the shortcomings of these projects, this thesis introduces some cutting edge efforts which combine solar home system technology with cellular technology and discusses the benefits of such a marriage of technology. Next, the research proposes some tweaks to this novel technology and provides a high-level economic demonstration of the spread of solar home systems in a community based on these modifications. It then takes this concept even further and proposes the addition of a DC/DC converter which could turn these individual solar home systems into a proper microgrid. This thesis elaborates on the development process of simulating such a microgrid in PSCAD, including the individual components of a solar home system and the specific task of designing the converter which would form the backbone of the proposed microgrid. The final simulations and analyses demonstrate a microgrid that is both technically and economically feasible for developing world applications.
85

The sustainable management of micro hydropower systems for rural electrification : the case of Bhutan /

Dorji, Karma Penjor. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 104-109). Also available via Humboldt Digital Scholar.
86

Electrifying Seoul and the culture of technology in nineteenth century Korea

Son, Min Suh, January 1900 (has links)
Thesis (Ph. D.)--UCLA, 2007. / Vita. Includes bibliographical references (leaves 212-237).
87

Rural distribution line protection

Rollman, William Henry. January 1939 (has links) (PDF)
Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1939. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed April 6, 2010) Includes bibliographical references (p. 26-27) and index (p. 28-30).
88

Computer Simulations Of Triboelectrification Of Particles And Their Trajectories In DC Electric Field

Puliyala, Srivathsa 01 December 2015 (has links)
This study aims to gain a fundamental understanding of the physics of triboelectri- cal charging of solid particles and the separation of the charged particles under an exter- nal DC electric field by computer simulations. A condenser model is used to implement charging mechanism and a soft sphere model is used to account for the Hertzian contact mechanics. The governing nondimensional parameters of the problem are identified and a parametric study is performed to investigate their effects on the charging efficiency and separation. The study finds relevance in a host of technologically important processes, such as recycling of plastic wastes, seed cleaning in agricultural industry and separation of coal from impurities in mining.
89

Análise de dificuldades técnicas e econômicas na inserção da cogeração pelas usinas sucroalcooleiras /

Queiroz, Gil Mesquita de Oliveira Rabello. January 2008 (has links)
Orientador: Dionizio Paschoareli Junior / Banca: Antonio Padilha Feltrin / Banca: Luiz Antonio Rossi / Resumo: Este trabalho traz a análise do potencial de geração das usinas termelétricas à biomassa de cana, destacando sua importância para a matriz energética nacional, e devido às suas características é um tipo de fonte que pode contribuir para uma diminuição de risco de déficit de energia previsto para os próximos anos. São estudadas alternativas para aumento da energia excedente, através da redução de consumo interno, em usinas consideradas de alta eficiência, ou seja, aquelas que possuem instaladas em seu parque industrial equipamentos como cadeira e turbogerador de alta pressão e temperatura, além do processo de eletrificação da moagem. Este trabalho apresenta também o novo modelo do mercado de energia sob o ponto de vista da venda de seu excedente e nas possibilidades de sua contração nos Ambientes de Contratação Livre (ACL) e Ambiente de Contratação Regulada (ACR), sendo que no (ACR) são analisados os resultados apresentados no PROINFA e tambem a participação das usinas termelétricas a biomassa de cana nos leilões de energia nova e fontes alternativas. No final são apresentadas as principais dificuldades encontradas atualmente para o aproveitamento do potencial da bioeletricidade, sendo a falta de conexão ao Sistema Interligado Nacional, a lentidão em se obter as licenças ambientais e o preço teto dos leilões. / Abstract: This work presents an analysis on the potential of thermoelectric generation using sugar-cane biomass as a fuel. The importance of such power plant for the Brazilian energy matrix is highlighted. Due to its inherent characteristics, the biomass-based power is an important alternative to reduce the energy deficit in the next years. The new Brazilian market, under the energy surplus selling viewpoint, considering the Free Contracting Ambience (Ambiente de Contratação Livre - ACL) and the Regulated Contracting Ambience (Ambiente de Contratação Regulada - ACR), is discussed. The results of PROINFA, Incentives Program to Alternative Sources of Electric Power, along with the ACR actions and new available energy, considering the biomass power plant participation, are presented. The increase of energy surplus by self-consumption reduction in sugarcane plants, in particular to those which are composed of high-performance steam-turbines, is discussed. The mills electrification is also considered in the energy consumption reduction studies. / Mestre
90

Análise de dificuldades técnicas e econômicas na inserção da cogeração pelas usinas sucroalcooleiras

Queiroz, Gil Mesquita de Oliveira Rabello [UNESP] 04 April 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-04-04Bitstream added on 2014-06-13T18:49:32Z : No. of bitstreams: 1 queiroz_gmor_me_ilha.pdf: 1218097 bytes, checksum: f7df8430ff1d3dac1c8791ba1bf274c8 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho traz a análise do potencial de geração das usinas termelétricas à biomassa de cana, destacando sua importância para a matriz energética nacional, e devido às suas características é um tipo de fonte que pode contribuir para uma diminuição de risco de déficit de energia previsto para os próximos anos. São estudadas alternativas para aumento da energia excedente, através da redução de consumo interno, em usinas consideradas de alta eficiência, ou seja, aquelas que possuem instaladas em seu parque industrial equipamentos como cadeira e turbogerador de alta pressão e temperatura, além do processo de eletrificação da moagem. Este trabalho apresenta também o novo modelo do mercado de energia sob o ponto de vista da venda de seu excedente e nas possibilidades de sua contração nos Ambientes de Contratação Livre (ACL) e Ambiente de Contratação Regulada (ACR), sendo que no (ACR) são analisados os resultados apresentados no PROINFA e tambem a participação das usinas termelétricas a biomassa de cana nos leilões de energia nova e fontes alternativas. No final são apresentadas as principais dificuldades encontradas atualmente para o aproveitamento do potencial da bioeletricidade, sendo a falta de conexão ao Sistema Interligado Nacional, a lentidão em se obter as licenças ambientais e o preço teto dos leilões. / This work presents an analysis on the potential of thermoelectric generation using sugar-cane biomass as a fuel. The importance of such power plant for the Brazilian energy matrix is highlighted. Due to its inherent characteristics, the biomass-based power is an important alternative to reduce the energy deficit in the next years. The new Brazilian market, under the energy surplus selling viewpoint, considering the Free Contracting Ambience (Ambiente de Contratação Livre – ACL) and the Regulated Contracting Ambience (Ambiente de Contratação Regulada – ACR), is discussed. The results of PROINFA, Incentives Program to Alternative Sources of Electric Power, along with the ACR actions and new available energy, considering the biomass power plant participation, are presented. The increase of energy surplus by self-consumption reduction in sugarcane plants, in particular to those which are composed of high-performance steam-turbines, is discussed. The mills electrification is also considered in the energy consumption reduction studies.

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