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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.
71

An economic evaluation of a bio-fuels industry in South Africa

Schuld, Renier A. 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2006. / ENGLISH ABSTRACT: The adoption of the White Paper on the promotion of Renewable Energy and clean fuels in 2003, opened the playing field for participants from other industries than the conventional petroleum, to participate in the fuel industry in South Africa. South Africa is a net importer of crude oil, which accounts for 92% of liquid fuels supply in South Africa. Although the country has significant coal reserves which can supply the country's demand for approximately 200 years, this energy source contributes significantly to CO, emissions. South Africa's participation in the Kyoto Protocol compels it to abide by its commitments to reduce these emissions between 2008 and 2012. The country's dependence on energy to fuel its growing economy, and the infiationary impact that oil imports has had on the country's economy, has prompted government to explore alternative sources of energy to reduce its dependence on fossil fuels and especially importing crude oil. As a result of this, and in an attempt to increase the potential for the successful implementation of ASGISA, government is exploring the feasibility of introducing an E10 fuel blend to the South African petrol blend. In view of th is, government has in it Accelerated and Sustainable Growth Initiative (ASGISA) targeted the development of the bio-fuels industry as an industrial sector that presents opportunities to create opportunities for sustainable growth and development. In view of this, the fiedgling fuel-ethanol industry (which is in its construction phase at the t ime of writing this report), faces lucrative prospects for the agricultural industry, especially maize- and ethanol producers. It is anticipated that the fuel-ethanol industry will create between 8000 and 10000 direct and indirect employment opportunities per plant. This will result in significant investment in rural areas as well. The creation of employment in the rural areas will prevent the large-scale urbanisation that has become a phenomenon in the past decade, as a result of dwindling agricultural industries. The production of ethanol presents the opportunity to earn foreign exchange, especially if the industry embarks on large scale export strategies. In addition to the export market, the local market for ethanol consist of the possible E10 petrol-blend and to supply Eskom with ethanol to fuel its gas turbine electricity generators at Acacia, Port Rex, as well as the anticipated generators at Atlantis and Mossel Bay. This document is a report on the investigation of the economic evaluation of a bio-fuel industry in South Africa. It will explore the current outlook for fossil fuel reserves, supplies and demand, both internationally and locally. It will report on the phenomenon of peak oil production and some opinions thereon . An investigation into the most probable biomass that can be used as feedstock for bio-fuel production will conducted. In this regard, specific investigation into maize, sugar cane (for fuelethanol) and Jatropha eureas (for bio-diesel) will be conducted. The report will explore the most efficient ethanol production processes, for both maize- and sugar-to-ethanol production, with the weight of the document to be attributed to the economic impact that the adoption of the fuel-ethanol programme / AFRIKAANSE OPSOMMING: Die publisering van die Witskrif oor die promosie van hernieubare energiebronne en skoon brandstowwe in 2003, het die speelveld vir deelname aan die brandstof industrie oopgemaak vir rolspelers buiten die konvensionele petroleum maatskappye. Suid-Afrika is 'n netto invoerder van ru-olie en het in 2004 ongeveer 92% van die totale vloeibare brandstowwe ingevoer. Alhoewel die land aansienlike steenkool reserwes het om te voorsien in die aanvraag vir die volgende ongeveer 200 jaar, dra hierdie energiebron aansienlik by tot die koolstofdioksied vrystellings. Suid-Afrika se deelname aan die Kyoto Protokol van 1998, dwing die land om te voldoen aan die ondernemings wat gemaak is om hierdie koolstofdioksied vrystellings te verminder tussen 2008 en 2012. Die land se afhanklikheid van energiebronne om groei te stimuleer, asook die inflasionistiese effek van olie invoere op die ekonomie, het die regering genoop om alternatiewe bronne van energie te ondersoek sodat die afhanklikheid van olie verminder kan word. Uiteenlopend hiervan en om die implementering van ASGISA te stimuleer, ondersoek die regering tans die moontlikheid om 'n E10 petrol vermenging in die petrol formule te spesifiseer. Uit die oogpunt van ASGISA (Accelerated and Sustainable Growth Initiative) van Suid-Afrika, het die regering die ontwikkeling van die bio-brandstowwe industrie geoormerk om geleenthede te skep vir volhoubare ontwikkeling en groei. Met die oog hierop, voorspel die etanol bedryf, wat ten tyde van die skryf van hierdie verslag nog in kontruksie was, winsgewende potensiaal vir die landboubedryf, veral mielie produsente. Dit word verwag dat die etanol bedryf tussen ongeveer 8000 en 10000 direkte en indirekte werksgeleenthede sal skep, veral in die landelike gebiede. Dit sal grotendeels bydra tot die voorkoming van die voortslepende ontvolking van die platteland wat oor die afgelope jare 'n verlammende effek op plattelandse gebiede gehad het. Dit word ook voorsien dat daar aansienlike belegging in die platteland sal plaasvind en al hierdie faktore sal bydra tot die voorkoming van verstedeliking . Die etanol bedryf skep die geleentheid om buitelandse valuta te genereer, veral as die industrie op uitvoere gaan konsentreer. Indien 'n plaaslike mark beoog word , sal die implementering van die E10 vermenging 'n besliste mark skep. 'n Alternatiewe mark wat ondersoek kan word, en wat groot geleentheid skep, is Eskom, wat tans ingevoerde diesel verbruik om hul gas turbine krag opwekkers by Acacia en Port Rex van brandstof te voorsien . Indien die beoogde turbines by Atlantis en Mosselbaai gebou word, sal die mark vir plaaslike etanol verdubbel. Hierdie dokument is 'n verslag oor die ondersoek wat gedoen is na die lewensvatbaarheid van 'n brandstof etanol bedryf in Suid-Afrika. Dit berig oor die huidige uitkyk oor die fossiel brandstof reserwes in die wereld en plaaslik. Dit opper die vraagstuk oor piek olie produksie fenomeen wat uiteenlopende debate ontketen het. Die verslag dek die waarskynlike bronne van biomassa wat aangewend kan word in die produksie van etanol, met spesifieke verwysing na mielies, suikerriet en Jatropha curcas. Die mees effektiewe produksie metodes word verder ondersoek wat van toepassing is op beide mielies en suikerriet. Die mees relevante deeI van die verslag is die ondersoek na die ekonomiese impak wat die industrie op die Suid-Afrikaanse ekonomie mag hê, waarna die nodige gevolgtrekkings en aanbevelings gemaak sal word.
72

Process engineering and development of post-combustion CO2 separation from fuels using limestone in CaO-looping cycle

Kavosh, Masoud January 2011 (has links)
Global CO2 emissions produced by energy-related processes, mainly power plants, have increased rapidly in recent decades; and are widely accepted as the dominant contributor to the greenhouse gas (GHG) effect and consequent climate changes. Among countermeasures against the emissions, CO2 capture and storage (CCS) is receiving much attention. Capture of CO2 is the core step of CCS as it contributes around 75% of the overall cost, and may increase the production costs of electricity by over 50%. The reduction in capture costs is one of the most challenging issues in application of CCS to the energy industry. Using limestone in CaO-looping cycles is a promising capture technology to provide a cost-effective separation process to remove CO2 content from power plants operations. Limestone has the advantage of being relatively abundant and cheap, and that has already been widely used as a sorbent for sulphur capture. However, this technology suffers from a critical challenge caused by the decay in the sorbent capture capacity during cyclic carbonation/calcination, which results in the need for more sorbent make-up; hence a reduction in cost efficiency of the technology. The performance of sorbent influenced by several operating and reaction conditions. Therefore, much research involves investigation of influencing factors and different methods to reduce the sorbent deactivation. Cont/d.
73

Právní regulace ochrany před znečišťováním z mobilních zdrojů / Legal regulation of protection against pollution from mobile sources

Ottomanský, Miroslav January 2012 (has links)
Miroslav Ottomansky Legal regulation of protection against air pollution from mobile sources The goal of this thesis is to map tools used for legal regulations of mobile pollution sources. Thesis focuses on problematic regulation of motor vehicles' pollution in Czech Republic, however it also outlines basic legal adjustements related to other mobile pollution sources. Thesis starts with basic introduction to this problematic followed by overview of international legal regulations and main conceptional tools used for legal regulations in European Union. In the chapter dedicated to the principles of european law in terms of regulation of mobile sources' pollution thesis tries to research how are those regulations already being applied to specific legal norms. One chapter is dedicated to protection of rights for convenient environment and their prosecution. In the next part of the thesis the normative regulations within emission standarts, approval of types, requirements for fuel quality and control of emissions of motor vehicles are examined. In the last chapter the new legal adjustment of mobile sources' pollution named in the law of enviroment protection is briefly explained in context with increasing number of problems with regulation of road traffic in cities. Key words: air pollution from mobile sources,...
74

Pale, male and stale : To what extent does achieving the UK’s carbon budgets rely on greater diversity within the energy sector?

Jones, Alexandra January 2019 (has links)
With increasing recognition that reducing carbon emissions from energy in the UK will make a significant contribution to the mitigation of anthropogenic climate change, and with carbon budgets forged following the Climate Change Act 2005 looking unlikely to be met, it is clear that sectoral changes are required to catalyse the decarbonisation process. Alongside the need for this industry to be at the forefront of decarbonisation, the energy sector needs to diversify and employ more women, Black and Minority Ethnic (BAME), LGBT and disabled people, as well as those from different social classes and varied educational backgrounds. In short, the energy industry in the UK presently has a diversity issue that transcends being an image problem; it is hampering progress. This masters’ thesis explores how the dual aims of decarbonisation and diversifying the workforce can aid one another, and the extent to which greater diversity within the energy sector could actually be the key to decarbonisation. Using transcripts from the interviews I conducted with eight individuals, as well as meta- analysis of existing data that examines the impacts of diversity in various industries, the ways in which greater diversity in the energy sector has the potential to be positive for decarbonisation are explored. Further, this paper also examines barriers to diversity, proposing a series of recommendations for industry and policy makers in order to create an energy sector that is more diverse. These recommendations can be found in the next steps section of the paper, which aims to provide guidance for those wishing to make the composition of their organisation more representative of wider society.
75

Strategic interactions in the management of fossil fuels : three essays on game theory in natural resource economics / Intéractions stratégiques dans la gestion des combustibles fossiles

Berthod, Mathias 05 September 2018 (has links)
Dans le cadre de cette thèse, je m'intéresse à la gestion des combustibles fossiles (pétrole, gaz naturel, charbon) en présence d'interactions stratégiques entre diffé­rents types d'agents. Dans un premier temps, j'étudie sous quelles conditions deux firmes asymétriques, exploitant une ressource non renouvelable, peuvent s'entendre autour d'un accord de coopération et ainsi former un cartel. J'analyse en parti­culier l'ensemble des accords possibles ainsi que la possibilité que ceux-ci soient acceptés par toutes les parties prenantes. Dans un second temps, je m'intéresse plus spécifiquement à l'incitation des pays membres du cartel de l'Opep à sures­timer ou sous-estimer leurs réserves de pétrole depuis l'instauration du système des quotas de production en 1982. Enfin, je caractérise la politique optimale d'un gouvernement en faveur du développement des technologies backstop au travers de subventions en R&D afin d'assurer la transition énergétique depuis des énergies fossiles polluantes à des énergies renouvelables non polluantes. Mais, je fais cette analyse dans le contexte où la production est contrôlée par une firme indépendante et lorsque le gouvernement ne peut pas implémenter une taxe sur les émissions. Un point commun de ces trois chapitres est la présence d'agents ayant des intérêts divergents. D'un point de vue méthodologique, j'utilise la théorie des jeux et, en particulier, les jeux différentiels dans les deux premiers chapitres. / This dissertation provides an analysis of the management of fossil fuels (oil, gas, coal) in the presence of strategic interactions between different types of agents. First, I study under which conditions two asymmetric firms, extracting a nonre­newable resource, may agree upon a cooperative agreement and, thus, merge into a cartel. I analyse, in particular, the set of feasible agreements and the possibility that every players accept one of them. Second, I focus more specifically on the incentives for the Opec members to over-report or under-report their oil reserves since the set of production quotas in 1982. Third, I characterize the optimal policy of a government in favor of the developing of backstop technologies through R&D subsidies in order to ensure the ecological transition from polluting fossil fuels to non-polluting renewable energies. However, I conduct this analysis in the context where the supply is controlled by an independent firm and when the government cannot implement a Pigovian tax on emissions. A common theme of these dif­ferent chapters is the presence of agents whose interests are contradictory. From a methodological point of view, I use game theory and, in particular, differential games in the two first chapters.
76

A Gap in the Grid : Attempts to introduce natural gas in Sweden 1967-1991

Åberg, Anna January 2013 (has links)
This thesis follows the process of introducing natural gas in Sweden and the construction of a Northern European gas grid from 1967 to 1991. Natural gas is a relatively unnoticed fuel in Sweden today, but this relative anonymity stands in contrast to an extensive historical activity that has taken place behind the scenes of Swedish energy policy. The single pipeline constructed between Denmark and Sweden in the early 1980s was both preceded and followed by many other attempts to construct a larger natural gas pipeline in the region made in the last 50 years. Åberg traces these attempts while discussing the complex and messy process of constructing and managing a transnational energy infrastructure.Åberg follows actors in Sweden and other countries in their attempts to negotiate and construct a natural gas infrastructure, and puts this process into a national as well as transnational context. The perceived risks and opportunities surrounding natural gas are examined, together with factors that have influenced the development of natural gas in a broader sense. By seeing the changing and messy natural gas projects as arenas where different actors construct and negotiate risks and opportunities, as well as contexualize the projects, Åberg shows how the natural gas sector in Sweden has evolved and taken shape.The study shows that natural gas in Sweden has suffered from unstable actor coalitions on different levels, a difficult market situation, and a changeful political context, especially with regard to energy policy. The import status of the fuel and the consequential transnationality of the natural gas infrastructure have also made the process of constructing a pipeline more complex. However, natural gas was introduced in Sweden, showing that when a strong enough actor coalition agreed that there was enough reason to warrant a natural gas introduction and was ready to join this endeavor, a connection could be achieved. This puts into question to what degree general explanations in terms of finance and policy drive energy decisions, and makes a case for showing how these explanations are adapted into their social and historical contexts in sometimes surprising ways. / <p>QC 20130507</p> / The integration of energy markets across system and nation boundaries
77

Design and development of a custom dual fuel (hydrogen and gasoline) power system for an extended range electric vehicle architecture

Van Wieringen, Matt 01 June 2009 (has links)
In recent decades there has been a growing global concern with regards to vehicle-generated green house gas (GHG) emissions and the resulting air pollution. Currently, gasoline and diesel are the most widely used automotive fuels and are refined from crude oil which is a nonrenewable resource. When they are combusted in an Internal Combustion Engine (ICE) they release significant amounts of air pollutants and Green House Gasses (GHG’s), such as NOx, CO2, SOx, CO, and PM10 into the atmosphere. The results of a feasibility study indicate that intermediary automotive propulsion systems are needed in order to begin a transition from fossil fuels to a clean, renewable transportation system. The Extended Range Electric Vehicle (E-REV) has been identified as an ideal intermediate vehicle technology. In this context, the objective of this thesis is to establish the scientific and engineering fundamentals for the design and development of a Dual-Fuel (hydrogen + Gasoline) Power Generation System for the E-REV sustainable mobility architecture. The devised power generation system is comprised of hydrogen and gasoline storage reservoirs, their respective fuelling systems, a Spark Ignition Internal Combustion Engine (SI ICE), an electric generator, batteries, as well as supplementary electronic systems. The batteries are used to provide power directly to the electric motors and are recharged with both the on-board electric generator and via plug-in capabilities. The developed prototype vehicle, which used a commercial Dune Buggy as a test bed, combined with the on-board rechargeable LiFePO4 battery pack, can provide the users with a daily commute range of ~ 65 [km] relying solely on the battery’s electric power, whereas for longer duration trips the use of the on-board generator would be necessary. The developed Dual-Fuel E-REV power generation system offers the following benefits when compared to the original gasoline ICE architecture: reduced emissions, improved acceleration (47% ↑), improved range (75% ↑), improved fuel economy (22% ↑) and decreased average fuel cost/km (29% ↓).
78

Environmental Kuznets Curve for Carbon Intensity : a Global Survey

Figueres, Fernando, Popova, Elena January 2011 (has links)
The Environmental Kuznets Curve is an inverted U-shaped relationship which demonstrates how environmental degradation increases as countries begin to develop and lowers as they become wealthier. The classical EKC measures the effects of GDP per capita (a country’s wealth) on pollu-tion. This paper is a study of the connection of a number of factors- GDP per capita, fossil fuels, al-ternative and nuclear energy, rural population and life expectancy at birth to the Environmental Kuznets Curve. Two econometric approaches are applied in order to test whether the variables have a more pronounced linear or quadratic form. Four income groups of countries are investigated in order to check if the state of development plays a crucial role in environmental deterioration. The results of the study point out that EKC does not apply for the chosen variables. From the regression for GDP, however, it can be concluded that EKC forms in 1990s.
79

Carbon geological storage - underlying phenomena and implications

Espinoza, David Nicolas 22 July 2011 (has links)
The dependency on fossil fuels faces resource limitations and sustainability concerns. This situation requires new strategies for greenhouse gas emission management and the development of new sources of energy. This thesis explores fundamental concepts related to carbon geological storage, including CO2-CH4 replacement in hydrate-bearing sediments. In particular it addresses the following phenomena: - Interfacial tension and contact angle in CO2-water-mineral and CH4-water-mineral systems. These data are needed to upscale pore phenomena through the sediment porous network, to define multiphase flow characteristics in enhanced gas recovery operations, and to optimize the injection and storage CO2 in geological formations. - Coupled processes and potential geomechanical implications associated to CH4-CO2 replacement in hydrate bearing sediments. Results include physical monitoring data gathered for CH4 hydrate-bearing sediments during and after CO2 injection. - Performance of cap rocks as trapping structures for CO2 injection sites. This study focuses on clay-CO2-water systems and CO2 breakthrough through highly compacted fine-grained sediments. Long term experiments help evaluate different sediments according to their vulnerability to CO2, predict the likelihood and time-scale of breakthrough, and estimate consequent CO2 leaks.
80

Climate Change in the Context of the Energy Reform in Mexico / El Cambio Climático en el Contexto de la Reforma Energética en México

Gutiérrez Nájera, Raquel 10 April 2018 (has links)
The author analyzes the Mexico’s energetic reform during the sexennial of 2013 to 2018. A historic study refers that Mexican energy matrix was based on fossil sources of energy as crude oil and natural gas. This represents nearly 90% of primary energy’s total production while the profit of non-fossil energy represents only 8% until 2012.Then, during the period of 2007-2012, the majority of the programmatic and normative instruments about climate change were generated. From 2013 to 2018, said the author, a national structural reform has been discussed. Thisamend includes Mexico’s energetic reform that proposes the «fossilization» of Mexican economy. This «fossilization» of the economy will favor the green growth and will constitutes itself as a barrier for Mexico’s fulfillment of international commitments assumed aboutclimate change, as well as its transition to a low carbon economy. / La autora analiza la reforma energética en México en el sexenio 2013 – 2018 a la luz de un análisis histórico sobre la matriz energética de dicho país, que al 2012 estaba basada en fuentes fósiles de energía: petróleo crudo y gas natural, que representaban conjuntamente cerca del 90% de la producción total de energía primaria; mientras que el aprovechamiento de energías no fósiles representaba solo el 8%. Asimismo, señala que en el periodo 2007- 2012 se generaron la mayoría de los instrumentos programáticos y normativos en materia de cambio climático, instrumentos que acompañaron la política internacional en la materia. En este sexenio 2013-2018, asevera la autora, se discute una reforma nacional estructural que incluye la reforma energética de México, que plantea la «fosilización» de la economía mexicana en aras de favorecer el crecimiento verde, que viene a constituirse en un obstáculo para que México pueda cumplir los compromisos internacionales asumidos en materia de cambio climático y transitar a una economía baja en carbono.

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