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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

EU energy policy after the Treaty of Lisbon : breakthroughs, interfaces and opportunity

Zhu, Feng January 2012 (has links)
University of Macau / Faculty of Law
82

"All the Crises Reached a Concerted Crescendo" - The Arab Oil Embargo and Why the United States Was Unprepared for It

Chilcote, Jonathan D. 01 December 2009 (has links)
During the 2008 spike in oil prices, oil companies and government officials were brought under close scrutiny as many Americans began to question why prices were able to rise so quickly. Americans had become accustomed to living in an economy where cheap oil was the norm, and demanded answers when that situation changed. What most of them did not know is that they were repeating history and mimicking the response to the 1973 oil embargo. Just as in 2008, the United States faced a crisis in 1973 with which it was unprepared to effectively cope. This thesis analyzes the reasons for and consequences of this lack of preparation in 1973 drawing on the writings of major policy makers and leaders of the time, most notably Henry Kissinger, Anwar el-Sadat, and Richard Nixon, Senate hearings testimony, recently declassified government documents detailing plans for U.S. invasion, and contemporary newspapers which recorded public perception. I argue that decades of living with cheaply priced oil, an over reliance on multinational corporations and a lack of understanding of Middle Eastern resentment toward these oil companies, combined with a fundamental misunderstanding of how oil and politics could be linked brought the United States to the ultimate near-decision of invading the Middle East. The 1973 oil embargo brought the United States face-to-face with the consequences of reliance on foreign oil and with the hardships that resulted from it. The United States had relied on oil companies to manage their interests in the Middle East for decades but in 1973 the situation changed forever. I close by considering the ongoing deep ties between the United States and the Middle East that are present still. The same problems that existed in 1973 exist today, and until those are corrected the United States and its economy will be deeply tied to the Middle East and to events in the region.
83

Investigating the introduction of e-mobility in South Africa

Otto, Willem Liebrecht 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: See PDF for abstract. / AFRIKAANSE OPSOMMING: Sien die PDF vir die opsomming.
84

Analise energetica global de um complexo petroquimico / Total site analysis of a petrochemical complex

Pires, Victor Flores da Matta 30 July 2003 (has links)
Orientador: Roger Josef Zem / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-11T09:37:16Z (GMT). No. of bitstreams: 1 Pires_VictorFloresdaMatta_M.pdf: 1892182 bytes, checksum: c990e6a52afe4eaf849fcd1d3d10d3af (MD5) Previous issue date: 2003 / Pires, Victor Flores da Matta / Resumo: A constante busca pela redução dos custos energéticos na indústria petroquímica, proporcionou o desenvolvimento de novas metodologias de otimização energética, dentre as quais se destaca a Análise Pinch. Esta metodologia apresenta bons resultados quando aplicada a processos isolados, porém, quando a análise é estendida a todo um complexo industrial, o resultado final não é satisfatório, uma vez que o sistema de utilidades e a interdependência entre os processos não são considerados. O presente trabalho apresenta a Análise Energética Global ("Total SUe"), que amplia a Análise Pinch da escala de processo para todo o complexo, incluindo o sistema de utilidades como parte integrante do problema, permitindo uma melhor compreensão da interface processo-utilidade, e um aumento do potencial de ganho energético. A metodologia é baseada nos Perfis Térmicos do complexo, obtidos a partir da Análise Pinch de cada processo individual, e sua interação com o sistema de utilidades, que possibilita a determinação das metas de consumo total de combustível, vapor, refrigeração, trabalho de co-geração e emissões atmosféricas do complexo. Com estas metas, é possível obter diagnósticos claros da eficiência energética do complexo, mostrando possibilidades de otimização, mesmo em unidades como alto grau de integração e eficiência energética. No trabalho ainda é proposta uma abordagem especial para as utilidades importadas e exportadas pela central de utilidades do complexo. A Análise Energética Global é aplicada a uma central de matérias pnmas e utilidades de um Polo Petroquímico, para cálculo de suas metas de energia. Também é realizado uma série de estudos abordando paradas de unidades; entrada em operação de nova unidade; modificações de processo; e modificações no sistema de utilidades. Os resultados obtidos confirmam a metodologia como uma excelente ferramenta de análise, que pode ser utilizada tanto na fase inicial do projeto, para auxiliar a construção da melhor configuração energética do complexo, como em complexos existentes, na análise de impactos no seu perfil energético, causados por mudanças nos processos / Abstract: The constant search of energy costs reduction in the petrochemical industry, provided the development of new energy optimization methodologies, which Pinch Analysis stand out. However, the goods results achieved in single process, with this methodology, were not materialised at the site boundary. This problem is caused by the interdependence of the processes and the utility sistem, that are neglected. The present work presents the Total Site Analysis, that extends Pinch Analysis from process leveI to site level, including the utilitiy system as a part of the problem, providing a better understanding of process-utility interface, and increasing the potential of energy profit. The methodology is based on the site's Thermal Profiles, build from Pinch Analysis of each individual process, and its interaction with the utilities system, that makes possible the determination of the targets of fuel consumption, steam, refrigeration, cogeneration work and emissions of the site. With these targets, is possible to obtain a clear diagnostic of the energy efficiency of the site, showing optimization possibilities, for even units with a high degree of integration and energy efficiency. The work presents a special approach to handle the imported and exported utilities by the site's utilities central. The Total Site Analysis is applied to a raw material and utilities central of a Petrochemical Complex, for calculation of its energy targets. Also, a series of studies is carried through, approaching stops of units; start-up of new units; process modifications; and utilities system modifications. The results confirm the methodology as''tll excellent analysis tool, that can be used as in the initial phase of the project, to assist the construction of the best energy configuration ofthe site, as in existing sites, to analyse site's energy profile impacts, caused by changes in the processes / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química
85

Energy management : technological, environmental and economical factors influencing the operating regime at Majuba Power Station

Greyvenstein, Laurence Cornelius 12 September 2012 (has links)
M.Ing. / In a country that ranks forty seventh on a list of fifty countries in a world competitive survey economic growth should be a high priority in South Africa. The main player in South Africa's energy industry took up the gauntlet and is moving to economic growth with the vision 'to provide the world's cheapest electricity for growth and prosperity." Competition was introduced among the electricity producers by a process called trading and brokering. Majuba power station, the most expensive electricity producer on the South African grid, was left out in the cold. Management of Majuba is challenged to derive resourceful strategies to ensure sustained profitability. These strategies will require a study into world trends to enable them to be more competitive. Crystal ball gazing is not needed to know that major restrictions on pollution of the atmosphere by industry will be curbed by stringent legislation. The current electrification programme in South Africa is bound to impact the shape of the daily load curve. Labour cost and the rate of inflation have been increasing and can be expected to keep on rising in the foreseeable future. It is important to know what macro effect these factors will have on the South African power industry. Majuba must be able to identify the changes lurking on the horizon and have contingency plans in place to meet these challenges. In this work different types of plant needed to meet the daily load demand are researched from literature. It is then compared to the types of plant installed in South Africa. This leads to the conclusion that the installed plant in South Africa is not sufficient to meet the daily demand effectively. A case study is done on Majuba Power Station that has been operating in a two shifting mode since December 1996. This means that the units is started every day to be on full load in time for morning peak and then shut down after evening peak. It is also shown that this mode of operation is proffitable for a relatively expensive power generator.
86

Essays in energy economics and industrial organization

Wang, Xueting January 2021 (has links)
In chapter 1, I study long term contracts in retail electricity markets. Deregulation of retail electricity markets gives consumer choices over contracts of different lengths. Long term contracts allow consumers to hedge against future price increase, but they can be more expensive than spot contracts. There is little empirical evidence on how consumers value long term contracts. Using a dataset from an incumbent retailer containing 10-year panel of consumer contract choice data, this paper analyzes consumers' valuations of long term contracts. I first document that a significant percentage of consumers actively choose long term contracts when they are more expensive than shorter contracts. To quantify the value of long term contracts and welfare implication of product innovation after retail deregulation, I build and estimate a dynamic model that incorporates risk preference, price expectations and consumer inertia. Counterfactual calculation shows that on average consumers gain about 6% per month from long term contracts. In chapter 2, I quantify the effect of introducing large-scale renewable energy on the wholesale electricity market. Renewable energy capacity has increased in many markets as renewable is crucial to reduce emission in the energy sector. More than 8GWh of wind capacity has been added in Texas between 2014 and 2017. Using hourly data from Texas, I find increasing daily wind energy production results in statistically significant reduction of wholesale electricity price for all hours of the day except 10pm, and the effect is larger during peak hours. Increasing wind production reduces output from both coal and natural gas power plants. Using hours when no transmission limit is binding and load is above 50th percentile in the load distribution, I find increasing hourly wind production reduces offer prices submitted by owners of fossil fuel power plants. In chapter 3, I study the effect of transmission limit on market outcomes. Wholesale electricity markets are often subject to transmission constraints that prevent efficient dispatch of power. Increasing renewable capacity demands transmission infrastructure investment. In 2011 to 2013, Electricity Reliability Council of Texas (ERCOT) constructed several high voltage transmission lines from the wind-rich west Texas to demand centers. Using data on electricity production, demand, price and information on grid congestion, this paper shows that an increase of 100MW in the transmission limit from the West to the North reduces the hourly output of fossil fuel generators in the North by 71.1MWh and decreases the price in the North by 0.17$/MWh when the transmission constraint from the West to the North is binding. Meanwhile, the increase of the transmission limit reduces dispatch of coal and combined cycle gas power plants in the North, but increases production of simple cycle and steam gas power plants in the North.
87

Variation of the coal stratigraphy and characterization of the Soutpansberg Coalfield, Limpopo Province, South Africa

Mawila, Edith Elizabeth Tintswalo 20 September 2019 (has links)
MESMEG / Department of Mining and Environmental Geology / The future of energy in South Africa depends on coal as it is one of the cheapest and most affordable sources of energy; however, some of the coal is uneconomical to mine due to the thickness and depth of the coal seams. For many years the coal resources of the Soutpansberg Coalfield remained untapped and limitedly researched and with the coal resources running out in the other coalfields, the Soutpansberg Coalfield remained the bright coalfield of tomorrow in South Africa. Coal seams in the Soutpansberg Coalfield occur within the Madzaringwe Formation. Three coal basins have been identified in this coalfield, are the Venda-Pafuri, Tshipise and Mopane. Sedimentological basin analysis of the coal stratigraphy and characterisation of the Soutpansberg Coalfield in the Makhado area, Limpopo Province was investigated within the farms of Rissik, Fannie, Duel, and Lurkin. The main purpose of the study was to establish the variation of the coal stratigraphy and how coal influenced the stratigraphy within the area. Fieldwork involved core logging and core sampling from the different farms within the Makhado coal area, while laboratory work included petrographic studies, investigation of the physical and chemical properties of coal. Core logging revealed the occurrence of coal zones where coal seams were intercalating with mudstones, but rarely with siltstone that formed the footwall of coal. Rarely was coal intruded by dolerite dyke as was the case along borehole W6610001. Core logging further revealed the sedimentary structures in the lithologies and the depth at which different lithologies were intersected. From these sedimentary structures, the environment of coal deposition was deduced supported by the geochemical analysis of major oxides and trace elements. Correlation of boreholes along the strike showed that the shale and mudrock were the predominant rocks within the coal horizon leading to the conclusion that these were the coal host rocks. Whole rock geochemical analysis was undertaken, using X-Ray Fluorescence Spectroscopy in order to establish the rock types and their trace element contents. The collected samples were analysed at the University of Venda, Department of Mining and Environmental Geology Laboratory, Siza Coal Services in Secunda and Council for Geoscience. The study indicated that the coal seams of the Soutpansberg Coalfield were deposited within the floodplain of a mixed-load fluvio-deltaic (fluvial and braided) systems. This sedimentary channel has been the major influence on the development of the coal seams. Locational changes in sedimentary facies above and below the coal seams within the study area has caused variations in the rates of compaction and subsidence which influenced the coal basin morphology and the coalification pattern. These two parameters (variations in the rates of compaction and subsidence) controlled the coal quality parameters, and coal seam thickness as well as the coal composition. The study confirmed that coal quality and thickness vary markedly from place to place in this coalfield due to varying local depositional environments. Most of the drill holes intersected mainly 3 coal seams, although in some cases either 2 or 5 seams were intersected. The thickest coal seam (borehole F578002) was 8 m. It was concluded that the coal was sub-bituminous to bituminous coal rank class (medium-volatile bituminous coal rank class). The coal had low moisture content ranging from 0.7-0.8%, and ash content ranging from 21.4-32%. The fixed carbon and volatile matter values of the coal samples ranged from 42.5 to 50.4% and from 25.2 to 27.4% respectively. The carbon and hydrogen were the main principal combustible elements in coal, however; carbon is the predominant one based on weight, constituting about 5.3% (the lowest) to 70.3% (highest) of the total. Due to the nature and thickness of the coal seams we conclude that this coal was economical to be mined and can be used for electricity generation and in cement grinding plants. A graph of coal gas concentrations over combustion time showed that methane (CH4) and carbon dioxide (CO2) had high gas concentrations, amounting to 1.75% and 1.70% respectively. / NRF
88

Review of the environmental authorization followed during the construction of Eskom's Kusile and Medupi power stations, South Africa

Molepo, Emmy 06 1900 (has links)
Environmental impact assessment follow-up has been widely addressed by various researchers. However, there is still a gap in the actual implementation of this process. This study addresses this gap by evaluating the effectiveness of implementing the environmental authorizations of Eskom’s Kusile and Medupi Power Stations during the construction phase. The main aim of the study is to determine whether the environmental authorization conditions were effectively implemented by project developers and whether full compliance which could lead towards sustainable development was at the forefront of Kusile and Medupi developments. The survey method was used whereby questionnaires were formulated and completed by fifty (50) participants involved in the implementation of both power stations’ environmental authorizations. The results showed that the importance of protecting the environment and overall compliance with the projects’ environmental authorization conditions are well understood and implemented. However, some of the responses indicated the difficulty in implementing certain environmental authorization conditions such as retaining existing vegetation cover. About Nineteen (19) external audit reports (of which nine were for Kusile and ten for Medupi) between the periods of 2008 to 2014 were reviewed and the audit results shown good percentage of over 90% compliance with the environmental authorization at both power stations. In conclusion, the environmental authorizations were well implemented by both Kusile and Medupi Power Stations. The environmental management through compliance with the environmental authorization is at the forefront of the Eskom’s developments and thus promotes sustainable development. The outcome of this study has a wide application that includes application to any new project that involves building infrastructure. / Environmental Sciences / M. Sc. (Environmental Management)
89

Logistic Strategies for an Herbaceous Crop Residue-Based Ethanol Production Industry : An Application to Northeastern North Dakota

Middleton, Jason Enil January 2008 (has links)
A mixed integer programming model is developed to determine a logistical design for maximizing rates of return to harvest, storage, transportation, and bioreflning of herbaceous crop residue for production of biofuels and feed for ruminant animals. The primary objective of this research is to identify the optimal location, scale, and number of pretreatment and biorefinery plants in northeastern North Dakota. The pretreatment and biorefinery plants are modeled under the assumption that they utilize recent technological advancement in AFEX and Simultaneous Saccharification and Fermentation, respectively. Potential feedstocks include wheat straw, barley straw, Durum straw, and com stover. Results indicate that the minimum ethanol rack price that will effectively trigger the production of cellulosic ethanol is $1.75 per gallon.
90

All together now : institutional innovation for pro-poor electricity access in sub-Saharan Africa

Gollwitzer, Lorenz January 2017 (has links)
Access to electricity is an important precondition to many aspects of human and economic development. Yet, in rural sub-Saharan Africa in particular, access rates remain very low — at an average of 17% and much lower in some cases. Rural electrification in Kenya, the focus of this thesis, had only reached 7% in 2014. Given the goal of universal electrification by 2030, formulated as part of Sustainable Development Goal 7, scalable and replicable approaches that are able to support productive and non-productive uses are required. Mini-grids are one promising solution to this problem, alongside grid extension and off-grid approaches such as solar home systems. However, their long-term operational sustainability has historically been a challenge. While the academic literature to date on sustainable energy access has largely been two-dimensional in its analysis of mini-grids (focusing on technology and economics or financing), this thesis contributes to an emerging body of recent contributions to the literature, which have begun to foreground socio-cultural considerations. Bridging the literature on collective action for common-pool resource (CPR) management and property rights theory, a refined theoretical framework is produced for the purpose of analysing the institutional conditions for sustainable management of rural mini-grids. The utility of this framework and of treating electricity in a mini-grid as a CPR is demonstrated via empirical analysis of three case studies of mini-grids in rural Kenya and evidence from 24 expert interviews. This yields insights on nontechnological approaches to addressing operational challenges relating to sustainable mini-grid management, e.g. fair allocation of limited amounts of electricity to different consumers in ways that are acceptable to the entire community. This thesis develops contributions to the literature on sustainable CPR management and collective action, property rights theory and energy access in developing countries. From these theoretical and empirical insights, it explores a novel institutional structure for sustainable management of pro-poor mini-grids in the form of a community–private property hybrid management platform, thereby opening up opportunities for future research into the implementation of such a platform. The thesis represents the first comprehensive attempt to analyse the institutional aspects of pro-poor mini-grid management as well as the first comprehensive attempt to treat electricity in a mini-grid as a CPR.

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