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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.
21

Energy models for electricity sector with green policies and technologies

Choi, Dong Gu 06 November 2012 (has links)
A variety of energy models and tools have been used for an comprehensive analysis of the complex energy systems and the design of pathway to sustainable energy world. This thesis analyzes three interesting problems in the electricity sector by developing and using suitable energy models. Chapter 2 investigates how to incorporate demand responsiveness for policy analysis in the electricity sector using a least-cost model. This study develops its own least-cost model which includes some characteristics for two important policies in the electricity sector, and suggests an iterative approach for incorporating the demand response to price change under new policy. Based on a case study, the state of Georgia, this chapter shows the effects of including demand response on the evaluation of policy. Chapter 3 is about new technology adoption pathways in the electric power system. In this chapter, by investigating the related status of policies and specifications of electric vehicles and wind power technologies in the U.S., several adoption pathways of the technologies in the U.S. eastern interconnection have been developed. This study develops four-serial models for the estimation of future economic and environmental impacts of the technologies' penetration. The results show that the total greenhouse gas emissions of the entire energy system do not substantially decrease even with a high level of electric vehicle adoption. The combination of two technologies, even more with appropriate policies, can notably decrease the total greenhouse gas emissions. Chapter 4 is a study about demand response programs, particularly optional time-based rates, for residential customers. This chapter analyzes the main reason that the participation of the current programs is low even though the programs have benefits. This study investigates two policy tools, a subsidy for flexible residential demand and a shared-savings mechanism based on consumption pattern changes, and examines the implementation of the tools and their potential to overcome the current inefficient operation.
22

Forecasts of electricity demand and their implication for energy developments in Hong Kong

Si, Yau-li., 史有理. January 1990 (has links)
published_or_final_version / Urban Studies / Master / Master of Social Sciences
23

The Impact of Energy Development on Water Resources in Arid Lands: Literature Review and Annotated Bibliography

Bowden, Charles January 1975 (has links)
No description available.
24

Modeling, simulation, and rational design of porous solid oxide fuel cell cathodes

Lynch, Matthew Earl 11 October 2011 (has links)
This thesis details research performed in modeling, simulation, and rational design of porous SOFC cathodes via development, extension, and use of the key tools to aid in the fundamental understanding and engineering design of cathode materials. Phenomenological modeling of triple phase boundary (TPB) reactions and surface transport on La₁₋ₓSrₓMnO₃ (LSM) was conducted, providing insight into the role of the bulk versus surface oxygen reduction pathway and the role of sheet resistance in thin-film patterned electrode measurements. In response to observation of sheet resistance deactivation, a modeling study was conducted to design thin-film patterned electrodes with respect to sheet resistance. Additionally, this thesis outlines the application of phenomenological chemical kinetics to describe and explain the performance and stability enhancements resulting from surface modification of La₁₋ₓSrₓCo₁₋yFeyO₃₋delta (LSCF) with a conformal LSM coating. The analysis was performed in close coordination with electrochemical experiments and transmission electron microscopy. Finally, the thesis describes conformal modeling of porous cathode microstructures using chemical kinetics and transport models. A novel application of conservative point defect ensembles was developed to allow simulations with complicated chemical surface kinetics to be efficiently coupled with bulk transport within the porous structure. The finite element method was employed to simulate electrochemical response conformal to sintered porous ceramic structures using actual 3D microstructural reconstructions obtained using x-ray microtomography. Mesh refinement, linear, and nonlinear reaction rate kinetics were employed to study the bulk versus surface oxygen reduction pathways and the effect of near-TPB nanostructure.
25

Public preferences towards future energy policy in the UK : a choice experiment approach

Tinch, Yelena January 2013 (has links)
The key focus of this dissertation is to produce research upon energy and climate change issues in the UK in a policy relevant and theoretically sound way. It aims to inform industry and policy makers to allow politically palatable, successful and effective future energy and climate change policy to be developed by identifying the preferences of the public for different policy scenarios. The Choice Experiment method was employed throughout this dissertation as the consistent methodological approach allowed for greater comparability of the results in addition to allowing the method’s robustness and reliability to be tested. The first part of this research (Chapter 3) is concerned with investigating attitudes and willingness to pay for future generation portfolio of Scotland by investigating household preferences for various energy generating options, such as wind, nuclear and biomass compared to the current generation mix. We identified the Scottish public have positive and significant preference towards wind and nuclear power over the current energy mix. We also found heterogeneity in public preferences depending on where respondents live which is reflected in their preferences towards specific attributes. Presence of non-compensatory behaviour in our sample is another element which was investigated in this part. Chapters 4 and 5 contain analyses of two independent choice experiments which were run in parallel. They take a UK-wide approach and investigate public preferences for more general areas of future energy and climate change policy, such as: carbon reduction targets, focus on energy efficiency improvements and attitudes to micro-generation versus large scale renewable generation. In addition the preferences for adaptation to and mitigation of climate change are investigated. Micro-generation is not often considered by energy companies when it comes to planning their generation strategies and was therefore of particular relevance to this research. As such Chapter 6 identifies the importance that the public places on this particular energy option and how it compares with their preferences towards other key energy and climate change policies of the UK. To analyse reliability of the results and to contribute to the theoretical field of stated preference valuation, each of the experiments contained two overlapping attributes, i.e. increase in level of micro-generation and an increase in total cost to a household, comparison of which was also carried out in Chapter 6. Finally in Chapter 7 the results found in the sections described above are discussed with reference to the policy background in the UK and Scotland. Also issues with the research and areas for further study are identified.
26

A design methodology for the supply of subterranean water through the use of wind energy

Marais, Brett Richard January 2005 (has links)
Thesis (M.Tech.: Civil Engineering)-Dept. of of Civil Engineering and Surveying, Durban Institute of Technology, 2005 xii, 89 leaves : ill. ; 30 cm / The Reconstruction and Development Programme adopted by the Government of National Unity is more than a list of the services required to improve the quality of life of the majority of South Africans. It is not just a call for South Africans to unite to build a country free of poverty and misery; it is a programme designed to achieve this objective in an integrated and principled manner. Based on the strategic objectives, as highlighted in the White Paper on Water Supply and Sanitation Policy, with regard to alleviating the chronic potable water shortages in South Africa, this thesis investigates a design methodology to supply potable water through the use of wind energy. The design focuses on small rural off-grid developments where grid electricity either has not or will not reach, and where renewable energy is the only viable option. This thesis provides an overview of wind energy and presents the fundamentals of wind power calculations. It also formulates an overview of the historic and present situation with regards to potable water supply, and reflects on the need for urgent intervention. The feasibility of using wind energy to supply potable water to rural communities in South Africa is explored in a case study. The various problem areas are identified and examined and a wide range of possible solutions are recommended. A final flow chart for the system design is proposed, thus ensuring comprehensive design methodology from which future design of similar systems can be based.
27

Understanding the centralized-decentralized electrification paradigm

Levin, Todd 27 August 2014 (has links)
Two methodologies are presented for analyzing the choice between centralized and decentralized energy infrastructures from a least-cost perspective. The first of these develops a novel minimum spanning tree network algorithm to approximate the shortest-length network that connects a given fraction of total system population. This algorithm is used to identify high priority locations for decentralized electrification in 150 countries. The second methodology utilizes a mixed-integer programming framework to determine the least-cost combination of centralized and decentralized electricity infrastructure that is capable of serving demand throughout a given system. This methodology is demonstrated through a case study of Rwanda. The centralized-decentralized electrification paradigm is also approached from an energy security perspective, incorporating stochastic events and probabilistic parameters into a simulation model that is used to compare different development paths. The impact of explicitly modeling stochastic events as opposed to utilizing a conventional formulation is also considered Finally, a subsidy-free lighting cost curve is developed and a model is presented to compare the costs and benefits of three different financial mechanisms that can be employed to make capital intensive energy systems more accessible to rural populations. The optimal contract is determined on the basis of utility-maximization for a range of costs to the providing agency and a comprehensive single and multi-factor sensitivity analysis is performed.
28

Exploring energy access and use trends in Tsumkwe, Namibia : an end-user perspective

Neumbo, Johanna Nangula 04 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The aim of this thesis is to establish a tangible metric by which to evaluate the impact of modern energy access on the livelihoods of rural Sub-Sahara African communities. The narrative is set in Tsumkwe, a remote rural Namibian location some 596 km north-east from the main capital city Windhoek. Initiatives aimed at rural electrification and energy provision are expected to reduce poverty as well as contribute to the community’s general wellbeing. However, determining the relationship between energy and development is quite a challenging undertaking. An analysis that is either exclusively quantitative or qualitative runs the risk of providing a skewed picture of the energy-development-poverty nexus. In this thesis, quantitative data is embedded within qualitative data as an attempt to examine the nexus and to translate how intervention programmes are transformed into outcomes in order to gauge success of a project. The transformative paradigm shaped the theoretical framework and informed the mixed-method research approach while the capability approach was used to analyse plurality and individualisation of policy impacts. Consequently, the role of place is positioned at the centre in gauging experiences of the poor vis-à-vis the importance of locating resources and capabilities to address socio-economic issues within a geographical location. The injustice of energy poverty can be viewed as unequal access to energy services (i.e. distributional injustice) as well as an intervention that failed to recognise the needs of certain groups and potentiality offered by place. From this, the concept of an energy poverty penalty is qualitatively developed. It was found that the penalty, although it is more pronounced in the low income groups, is exacerbated by choice offered in an energy basket thus affecting non-income poor households too. Therefore, the energy poor are not necessarily income-poor. It is finally concluded that while sustainable energy interventions offer the possibility to reduce energy poverty and the attendant human wellbeing index improvement they need to be grounded in a robust information base to track progress towards targets. Most existing indicators and composite indices assessing access to energy, the degree of development related to energy and deprivation of access to modern energy fail to account for the energy poverty trap. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis is om ‘n tasbare meting daar te stel om die impak to toegang to moderne energie daar te stel in landelike gebied in sub-Sahara Afrika te evalueer. Die studie is uitgevore in Tsumkwe, ‘n afgeleë landelike gebied in Namibië, sowat 596 km noordoos van die hoofstad, Windhoek. Daar word veronderstel dat inisiatiewe wat daargestel word om energie en elektrisiteit toeganglik te maak vir landelike gebiede en gemeenskappe, verarming sal teewerk en gemeenskappe kan ophef. Dit is egter moelik om die verhouding tussen energie verskaffing and vooruitgang te bepaal. ‘n Studie wat net kwalitatief of kwantitatief gebaseer is, sal nie die ware toedrag van sake uitlig nie. In hierdie tesis is kwalitatiewe data verweef met kwantitatiewe data om vas te stel presies hoe effektief programme is wat daargestel is om energie aan landelike gebiede te lewer. Die transformatiewe paradigma het die teoretiese raamwerk gevorm en gelei tot die kombinasiemetode navorsingsbenadering terwyl die moontlikheids benadering gebruik is om die pluraliteit en individualisering van die beleidsimpakte te ontleed. Gevolglik, is die rol van plek in die middelpunt van die ondervindings van die armes vis-à-vis die belangrikheid van die verkryging van hulpbronne en vermoë om sosio-ekonomiese kwessies binne ‘n geografiese ligging te hanteer. Die feit dat landelike gebiede verarm is wat energie en elektrisiteit voorsiening betref, kan toegeskryf word aan die volgende: ongelyke toegang to energie dienste, programme wat nie die behoeftes van landelike gemeenskappe aanspreek nie en die potensiaal van plek waar die program aangepak word is nie voldoende aangespreek nie. In die lig van hierdie potensiële oorsake van energie verarming is die konsep energie aarmoede boete kwaliteitsgewys ontwikkel. Dit is gevind dat die boete, wat meer van toepassing is op lae inkomste groep is, beinvloed word deur die keuse wat beskikbaar gemaak is in terme van energie voorsiening. Hierdie keuse het ook ‘n invloed op die “geen-inkomste” arm groep in ‘n gemeenskap. Dit is dus duidelik dat diegene wat energie verarm nie noodwending geldelik ook verarm is nie. Die studie, ter opsomming, het tot die slotsom gekom dat hoewel tussenkomende programme wat daar gestel word om volhoubare projekte aan te bied vir energie voorsiening in landelike gebiede, energie verarming kan verminder, dit nie effektief genoeg is tensy dit opgevolg word met duidelike doelwitte nie. Die bestaanded aanduidings vir toegang tot energie, aanduidings wat energie toegang en vooruitgang evalueer is nie werklik effektief genoeg nie.
29

Electronic voltage regulator technology for rural electrification

Serdyn, J. J. 03 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--Stellenbosch University, 2008. / ENGLISH ABSTRACT: This thesis discusses the development of a 5 kVA single phase AC voltage regulator, specifically designed to assist in the reduction of electrification costs in sparsely populated rural areas. The voltage regulator is based on a solid state auto-transformer tap changer, designed to be robust and maintenance free. Electrification cost savings can be realized if the length of the LV network can be extended to reach more households. To accomplish this, a voltage regulator can be installed onto the extended LV feeder at the point where the LV voltage will drop below the minimum valid voltage, thereby boosting the voltage downstream and enabling more customers to be connected. A variety of voltage regulator topologies were investigated to obtain the best topology for the application. The voltage regulator design is discussed in detail with careful attention given to the power loss incurred, surge voltage protection requirements, protection coordination with the existing LV network and the thermal design requirements. An electronic controller based on a digital signal processor together with an appropriate power supply is designed and built. The software to control the voltage regulator is developed, integrated with the hardware and debugged. The complete voltage regulator is evaluated through extensive laboratory testing and field trials are performed to verify the performance of the device. / AFRIKAANSE OPSOMMING: Hierdie tesis bespreek die ontwikkeling van ‘n 5 kVA, enkelfase, wisselstroom spannings reguleerder, spesifiek ontwerp om koste besparings te bewerkstellig in die elektrifisiëring van yl bevolkte landelike gemeenskappe. Die spannings reguleerder se ontwerp is gebaseer op ‘n outo-transformator tap wisselaar met vaste toestand skakelaars, om sodoende robuust en instandhoudings vry te funksioneer. Elektrifisiërings koste besparings is moontlik indien die laag spannings distribusie kabel verleng kan word, om sodoende elektrisiteit aan meer huishoudings te voorsien. Om dit mootlik te maak kan ‘n spannings reguleerder geinstalleer word op die punt waar die kabel spanning onder die minimum toegelate spanning daal. Sodoende word die spanning weer verhoog aan al die huishoudings wat aan die verlengde gedeelte van die kabel verbind is. ‘n Verskeidenheid uiteenlopende spannings reguleerder topologieë is ondersoek om die beste topologie vir die toepassing te identifiseer. Die ontwerp van die spannings reguleerder is baie deeglik bespreek en spesifieke aandag is gegee aan die verliese, spits opwelling spannings beveiliging, sinkronisasie met die huidige laag spannings netwerk se beveiligings meganismes en die termiese ontwerp van die stelsel. ‘n Elektroniese beheerder, gebaseer op ‘n digitale sein verwerker, tesame met ‘n toepaslike kragbron is ontwerp en gebou. Die nodige sagteware om die spannings reguleerder te beheer is ontwikkel, geintegreer met die hardeware en ontfout. Die volledige spannings reguleerder is ontleed deur intensiewe toetse in die laboratorium en toets installasies op laag spannings netwerke, om sodoende die nakoming van die werks verrigting vereistes van die toestel te bevestig.
30

Ethnographic and Class I Records Searches for Proposed Solar Energy Zones in California, Nevada, and Utah for the Bureau of Land Management’s Solar Programmatic Environmental Impact Statement

SWCA Environmental Consultants, Bureau of Applied Research in Anthropology, University of Arizona, Stoffle, Richard W., Van Vlack, Kathleen A., Johnson, Hannah, Dukes, Phillip, De Sola, Stephanie, Simmons, Kristen 12 1900 (has links)
The United States Department of the Interior, Bureau of Land Management (BLM) National Operations Center obtained American Recovery and Reinvestment Act of 2009 funding to conduct an ethnographic overview of select proposed solar energy zones (SEZs) to augment the research that had been conducted for the Programmatic Environmental Impact Statement for Solar Development in Six Southwestern States (Draft Solar PEIS). The objective of this project was to solicit tribal identification of traditional cultural properties and sacred landscapes, religious and traditional use sites, significant ethnobotanical resources, other sensitive or significant resources (including visual), and tribal perspectives on the direct and indirect effects of solar energy development through oral interviews and on-site visits to proposed SEZs in Arizona, California, Nevada, and Utah. SWCA Environmental Consultants (SWCA) was selected to perform this work, assisted by the University of Arizona’s Bureau of Applied Research in Anthropology (BARA). As the project progressed, the list of participating tribes was modified to accommodate changing tribal needs and requests. When the tribe that had requested to participate in an ethnographic study for three of the California SEZs (Imperial East, Iron Mountain, and Riverside East) was unable to participate, the scope of the project was modified. In the Draft Solar PEIS, the high cost of conducting Class I archaeological records searches for the four California SEZs had precluded that research; the current project was modified from ethnographic interviews to a Class I records search for all four California SEZs (Imperial East, Iron Mountain, Pisgah, and Riverside East) by SWCA. BARA conducted ethnographic studies for Amargosa Valley, Delamar Valley, Dry Lake, East Mormon Mountain, Gold Point, and Millers in Nevada (inclement weather prevented visits to Dry Lake Valley North), and for Escalante Valley, Milford Flats South, and Wah Wah Valley in Utah.

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