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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.
191

Information for energy-related environmental policy : the role of disaggregated dynamic energy demand modelling

Fouquet, Roger January 1997 (has links)
Public concern about energy-related environmental damage has put pressure on governments to enhance abatement policies. This has in turn led to increasing demands for information about and analysis of expected and optimal levels of environmental quality, and the means of influencing these levels. Energy demand modelling can act as a valuable tool in the production of this information, particularly where it relates to future levels of environmental quality and to how policy intervention can alter constraints facing consumers in order to achieve desired levels. The thesis focuses on two features of energy demand analysis. First, major developments in dynamic econometrics, and in particular the cointegration approach, have enabled energy demand modellers to incorporate long run equilibrating relationships between energy use and its main determinants, such as economic activity and relative prices, within a dynamic framework. Second, the existence of a diverse market for energy both in terms of the fuels used and the users suggests that energy demand should be analysed at a disaggregated level. The purpose of this thesis is to examine whether disaggregated dynamic energy demand modelling can provide additional valuable information for the formulation of environmental policy. The core of the thesis takes the form of six separate papers: three review papers link dynamic energy demand modelling with environmental policy and three case study papers use disaggregated dynamic energy demand modelling to examine aspects of future United Kingdom energy-related environmental quality and how it can be altered through changing the constraints facing consumers. While theory and traditional econometrics have provided useful information about energy consumption behaviour, the introduction of the cointegration approach and the error correction model are enabling economists to estimate more reliably the long run relationships between energy demand and its main determinants, and the gradual adjustment of consumers towards equilibrium consumption levels after a disequilibrating disturbance. This new information is giving a greater understanding of how to achieve desired future environmental quality levels. The heterogeneous nature of energy use, both in terms of the fuels used and their users, indicates that the accuracy of elasticity estimates and, thus, the quality of information they can provide for environmental policy might be improved through the disaggregation of dynamic energy demand modelling. Employing the cointegration approach and sectoral and fuel specific error correction models to generate estimates of income, three separate papers provide evidence in support of this argument. Individually, these papers provide information about sectoral and fuel specific elasticities, about how residential users alter their behaviour as economic constraints change and about how certain car users alter their fuel consumption patterns when provided with adverse environmental publicity about fuels. Together, these papers suggest that there exists considerable variation in income and real price elasticities between sectors and fuels, and that using the estimates generated by such disaggregated dynamic models will provide greater accuracy than aggregated and static models. These variations are of particular importance to environmental policy makers because of the difference in environmental impact associated with different fuels. The thesis, therefore, finds that, by generating more detailed and reliable elasticity estimates, disaggregated dynamic energy demand models provide new and valuable insights for the formulation of environmental policy. It concludes that disaggregated dynamic energy demand modelling will form an increasing share of the models used for environmental forecasts and policy analysis - although the overall interest in this area of research may shift as levels of certain energy-related environmental indicators improve (eg carbon dioxide, sulphur dioxide and nitrogen oxides) and others worsen (eg volatile organic compounds and PM10). The thesis suggests that considerable refinements in energy demand modelling can be made, both in the methods used and in the focus of empirical studies, which will lead to further improvements in the formulation of environmental policy.
192

Modelling dry process cement kilns using acid/alkali mixing technique

Tosunoglu, Melahat January 1984 (has links)
At present, the main cost items associated with cement manufacture are due to the fuel and the electric energy consumed. Reducing the fuel cost can be achieved either by reducing the specific consumption or by using lower grade cheap fuels in the process. One of the simplest and most important methods of reducing the specific consumption is the flame control, which, in addition to saving energy also results in better quality product and steadier kiln operation. By changing the process from wet to suspension preheater dry system, the industry can reduce its fuel consumption up to 50%. Application of precalcining system to these dry process suspension kilns can even further improve the heat transfer conditions in the kiln and the preheater. Precalcining can be achieved either by introducing some proportion of the total heat input into the riser duct connecting the kiln to the preheater or by adding another stage of separate calciner chamber. The advantages obtained by precalcining are several, some of the important ones being increase in production capacity for a given kiln unit, improved kiln lining life, steadier operation, better heat transfer conditions in suspension state for the decarbonation of the material, and the possibility of utilizing lower grade fuels in the secondary firing unit in the calciners. In order to achieve the aim of energy saving, it is essential to have a very good understanding and investigation of the aerodynamics of the furnace, and the effects of the modifications introduced to the system for energy saving purposes, like auxiliary burners. Modelling techniques prove to be very useful in such cases. In this present work, the technique of physical modelling has been chosen and the acid/alkali mixing method has been applied for flow visualization. By comparing the model results concerning the length and behaviour of the flame under different kiln operating conditions with the results of the experiments carried out on the prototype itself by earlier workers, the reliability of the technique and its usefulness in flame studies have been proved. By applying the same technique and flow visualization methods to a 1 :40th scale down geometric model of a suspension preheater kiln with auxiliary firing arrangement, the optimum operating conditions for such systems in case of secondary firing have been determined. It has been established that for the auxiliary firing systems in four-stage cyclone preheaters with combustion air being supplied through the kiln, the proportion of the fuel supplied at the back-end of the kiln in the riser duct should not exceed 30% of the total heat input, the optimum value being 27%. In designing auxiliary burners for such systems, it has also been found that the stream to jet velocity ratios (p) should be in the range 0.62 < p < 0.83 for burners 30&deg; inclined to the horizontal, and 0.41 < p < 0.49 for the burners perpendicular to the stream flow in the riser duct for purpose of having an axisymmetric flame in the riser duct.
193

The effect upon UK energy supply schedules of the use of combined heat and power with district heating

Armson, R. January 1984 (has links)
The widescale use of combined heat and power with district heating will have a significant effect upon the quantities of primary and secondary fuels used in the United Kingdom. A new methodology for investigating the complex technological interactions between supplies and demands for fuels is developed, and the effect of sample CHP/dh scenarios calculated. Particular attention is paid to electricity generation to determine the impact of CHP/dh upon the operation of the merit order.
194

The human dimension of domestic energy use : an integrated approach

Hitchcock, Guy St John January 1992 (has links)
Domestic energy consumption is a multifaceted phenomenon which is dependent on both the social and technical characteristics of domestic households. In this thesis it is argued that such a phenomenon is best understood using an integrated approach, combining both the physical and social theories of energy use. Such an integrated approach is developed with the use of systems theory and focuses on the interaction between the physical and social aspects of the household. This integrated approach is used to analyse UK and US domestic energy consumption patterns and is compared with a purely physical and a purely social analysis. These analyses also highlight the inadequacies of the physical or social approach and demonstrates the difficulty involved in trying to consider both in a single integrated analysis.
195

Telecommunications networks for remote electricity supply metering and load control

Brown, Paul Anthony January 1990 (has links)
The aims and objectives of this thesis are to investigate remote electricity supply metering and load control in terms of the now availble UK Electricity Supply Industry (ESI) private and national telecommunications networks, the intelligent building, the home computer and domestic energy management concepts. This work commences with an overview of private telecommunications systems utilised within the U.K. electricity supply industry together with those network services provided by Public Telecommunications Service Operators (PTO's) for customer access (Chapters 1 and 2). The thesis continues by describing the meter reading and billing processes (Chapter 3) and introduces the concepts of remote metering, the consumer billing interface (Chapters 4 and 5), load control and spot pricing theory (Chapter 6). A review of recent load control and remote metering field trials, conducted in the UK, including feasibility studies are then detailed (Chapter 7). A mathematical analysis of two basic approaches to the principle of 'idle-line' working is also considered (Chapter 7). The 'intelligent home' concept and the customer billing interface are then considered in conjunction with the development of a 'home computer' applications strategy (Chapter 8). The development of text, communications and control simulation on the BBC microcomputer, are then detailed by reference to the 'Adaptive Microprocessor based System for Experimentation in the Transmission of Text' (AMTEXT) developed to test the feasibility of the home computer applications strategy developed in Chapter 8 (Chapter 9). The concept of 'idle-time working is then introduced coupled with the concept of 'integration' by way of the national telecommunications network services. Proposals for a Modular Integrated Data Aquisition System (MIDAS) are then considered as a means of illustrating a practical application of both integration and idle-time working (Chapter 10). The thesis continues by considering network integrity, security and reliability in terms of network architecture and the development of a strategy for quantifying network resilience as a design parameter (Chapter 11). Finally, the thesis concludes by summarisirig the work undertaken and the results obtained with respect to the initial objectives, and details potential areas for further research.
196

Evaluation of the design, construction and operation of a gas fuelled, engine driven heat pump, and its possible role in a UK market

Newport, C. A. January 1983 (has links)
This thesis describes the results of several years work on the design, construction, testing and evaluation of a gas fuelled, engine driven heat pump and its possible role in a future U. K. market. In 1977 a joint venture was embarked upon by the Open University Energy Research Group, Lucas Aerospace and Milton Keynes Development Corporation to design, manufacture and install a gas fuelled heat pump in a rented house, and to monitor its performance in real operating conditions. It was one of a number of projects in the field of heat pump research and development supported by the Department of Energy. Due to a delay in receiving research funds however, and because of the size of the unit, it was impossible to install the system in a suitable property and so it underwent an intensive laboratory test programme simulating various load patterns and operating conditions. The heat pump, using air as its source of heat was driven by a 360 cc single cylinder marine engine converted to run on natural gas. The work was completed in 1980 and the heat pump was found to work well and justified the design assumptions made, after allowing for the poor performance of the engine used. At 6°C (ambient) an output of 14 kW was achieved with an overall efficiency or C. O. P. of 1.1 which compares favourably with a typical seasonal gas boiler efficiency of around 0.65-0.70. As well as giving a full technical description of the heat pump system, plus an analysis of the various individual components, the thesis looks at the historical development of heat pumps generally and briefly considers the applications to which heat pumps can be put in domestic, commercial and industrial markets, and the possible economies this would bring. It concludes by looking at the future work needed in order to achieve these ends.
197

A dynamic physical energy model of the United Kingdom

Barrett, M. A. January 1981 (has links)
This report describes the structure and simulation results of a dynamic physical model of the UK energy system. The model traces the hourly flows of energy from energy sources through various energy converters and stores to useful energy demands. Effects such as the temporal and climatic dependence of demands have been accounted for. Technical data has been collected so that it is possible to simulate the performance of the system as it was in 1976 or as it might be at some future date. The model has been validated against measured data and has been used to simulate the UK system with changed demands and new conservation and supply technologies.
198

Zero energy for the Cyprus house

Serghides, Despina January 1993 (has links)
The thesis aims at the optimization of the regulatory systems inherent in domestic architecture through choice of orientation, building materials and the use of natural resources of energy, to achieve comfort conditions without the need for mechanical heating and cooling for the Cypriot climate. The thesis is classified in six chapters as follows: CHAPTER 1 In this chapter, analysis of the energy situation in Cyprus to investigate the potential for energy saving in houses and the possible environmental improvement is carried out. For this, existing and newly built houses are evaluated to identify deficiencies in the regulatory systems inherent in the built form that result in heating and cooling demands. CHAPTER 2 The prevailing climatic conditions in Cyprus are analyzed, in this chapter, to assess how energy demands for heating and cooling arise in domestic buildings and to evaluate the free energy systems available to contribute to these requirements. Moreover in this chapter standards of comfort for single family detached houses in Cyprus are established, through investigation of current thermostat settings and reviews of thermal comfort studies, so that they may be taken as a basis in the optimization study. CHAPTER 3 This chapter deals with the optimization of a specific house type, to be designed in an ideal environment, to the point of zero fuel consumption for heating and cooling with the aid of microcomputer programmes for thermal analysis. Initially simplified thermal calculations are carried out by using "Method 5000°, a well established method adopted by the Commission of the European Community Handbook. These are followed by detailed hourly simulations of selected variants using dynamic simulation model SERIRES. CHAPTER 4 This chapter also makes use of thermal calculations as chapter 3, and concludes to comparative assessment of results obtained under chapter 3, and design recommendations for new houses through economic analysis of the varied design measures. From those the profile of the "Zero Energy House for Cyprus" is outlined. CHAPTER 5 The study in this chapter identifies the occupants' factors that influence the efficiency of building performance and the thermal environmental conditions of the "Zero Energy House". It analyses the intervention of the occupants in the design, which is reflected in the variable of fenestration. The analysis is carried out interdependently, in various combinations of shading and ventilation profiles, in computer simulations using thermal analysis programme "AGRI". A case-study further investigates the thermal effects of the user interaction with the building and confirms the validity of the simulation results. The proposed strategies, at the end of the chapter, aim at reducing the operational counter-effects on the building design. CHAPTER 6 The conclusions are outlined in the form of criteria for the selection of different design alternatives. These are based on flexibility, operational ease, potential thermal efficiency and elimination of constraints for securing optimal performance for "Zero Energy Houses" for Cyprus.
199

Power system optimisation and stability studies using real-time simulation

Williams, S. K. January 1986 (has links)
No description available.
200

Desenvolvimento de tecnologia educacional para o uso racional de energia /

Teixeira, Robinson Carlos. January 2008 (has links)
Resumo: A energia é um dos produtos de fundamental importância na sociedade moderna e tem assumido, no momento atual, um papel bastante significativo dentro do contexto da questão ambiental e da busca do desenvolvimento sustentável. Assim, vários projetos, artigos, discussões e leis resultam da convergência de idéias diante da real necessidade de se desenvolver ações e temas que chamem a atenção para problemas relacionados à sua produção e ao seu consumo. Embora a eficiência energética seja uma área em que toda a nação tem responsabilidade, cabe à comunidade científica desenvolver atividades, no domínio da educação, que permitam a divulgação das informações e dos programas existentes e promover boas práticas. Diante dessa necessidade, foi desenvolvida uma ferramenta educacional, baseada nas novas tecnologias, que permite realizar ações de educação informal para a conscientização do uso racional da energia elétrica nas residências. Essa ferramenta educacional constitui-se de um Ambiente Integrado de Projetos Interdisciplinares, denominado WebProInter, concebido para utilização em trabalhos que fazem uso da metodologia da Aprendizagem Baseada em Projetos (PBL) e do portal eletrônico "Vigilantes da Energia", no qual são disponibilizados um conjunto de informações, ferramentas e metodologias que auxiliam no desenvolvimento de uma rede social com fins educacionais. Essa ferramenta foi concebida e desenvolvida utilizando-se o construcionismo proposto por Papert. Para aplicação dessa ferramenta, foi criado um curso destinado a alunos do Ensino Médio, denominado "Vigilantes da Energia", considerando-se referências metodológicas e filosóficas baseadas na pesquisa-ação colaborativa. O curso "Vigilantes da Energia" também foi concebido para se testar a eficiência e as vantagens da utilização de ambientes como o WebProInter... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Energy is a product of fundamental importance in modern society and it has been assuming nowadays, a quite significant role in environment and sustainable development issues. Therefore is of paramount importance for the improvement of life standard in all countries the adoption of actions in order to optimize the production and the consumption of energy. Although the energy efficiency to be an area where the whole nation has responsibility, is necessary that the scientific community develops educational skills in order to popularize the information about the existent programs concerning the rational use of energy. In accordance with this need, an educational tool was developed, based on new technologies, that allow one to accomplish actions of informal education for the understanding of the rational use of electrical energy in residences, , through practices in informal education. Such educational tool is constituted of an Integrated Environment of Interdisciplinary Projects, callled WebProInter, which has been concepted to be applied in works that make use of the Project Based Learning (PBL) methodology. This tool is also composed of the website "Energy Watchers", where one finds a set of information, tools and methodologies that assist the development of a social network educational wise. This tool has been concepted and developed based on the theory proposed by Papert. As an application of this tool, the proposal of a course called "Energy Watchers" has been made, which aims at reaching high school students. Such course considers methodologies and philosophical references based on collaborative researchaction, and has also been made with the purpose of testing the efficiency and advantages of the use of environments such as WebProInter, being your main objective to increase the multiplier agents formation regarding rational use... (Complete abstract click electronic access below) / Orientador: Jânio Itiro Akamatsu / Coorientador: Galeno José de Sena / Banca: Rubens Alves Dias / Banca: Oscar Armando Maldonado Astorga / Banca: Silvio Henrique Fiscarelli / Banca: George Alves Soares / Doutor

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