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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.
241

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.
242

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.
243

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.
244

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.
245

Power system optimisation and stability studies using real-time simulation

Williams, S. K. January 1986 (has links)
No description available.
246

Desenvolvimento de um modelo educacional para a conservação de energia

Dias, Rubens Alves [UNESP] 06 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-06Bitstream added on 2014-06-13T19:26:26Z : No. of bitstreams: 1 dias_ra_dr_guara.pdf: 2310980 bytes, checksum: 56d56c7167fc9de0ceaa3ddb17fa8a20 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As iniciativas destinadas ao uso racional da energia, em virtude da característica integradora de conceitos desse tema, revelam-se tanto nas ações mais elementares, como a eliminação do desperdício, quanto nas análises mais rebuscadas, envolvendo estudos técnico-econômicos para a escolha de uma determinada intervenção. Nesse leque de opções, a educação é um elemento sempre lembrado e tido como condição de significativa importância para levar adiante a mudança de valores dos consumidores de energia em prol da economia de recursos naturais e de capital. Todavia, a abordagem educacional do uso racional da energia, apesar das iniciativas pioneiras, necessita ser focalizada no indivíduo, no que se refere aos processos afetivos e cognitivos, para posteriormente agregar as informações de caráter técnico, visandose o incentivo à ação social. Para esse desenvolvimento, além dos estudos oriundos das atividades do setor energético, agregaram-se informações de domínio da psicologia e da educação, balizando-se pela legislação vigente e pelos critérios paramétricos da educação no Brasil. A característica transversal do tema, através do ensino contextualizado, cria condições favoráveis à construção do conhecimento a respeito da energia e seu uso e, portanto, tem potencial de promover o desenvolvimento sustentável pela cidadania. O presente modelo educacional para a conservação da energia tem o objetivo de contribuir com o setor energético visando sistematizar os conteúdos nos ensinos fundamental, médio e superior a partir de ferramentas efetivas para os processos de ensino-aprendizagem, auxiliando os educadores desses segmentos no planejamento do ensino. / The initiatives aimed to energy conservation, due to its integrating characteristics, conduct many actions, since the energy waste elimination to the most sophisticated tool of intervention, as viability studies. In this range of options, the education always is remembered, because it is an important way to get the change of human values in a favor to save natural resources and capital. However, the educational broach of rational energy use, in spite of pioneering actions, needs to be person focused, relatively to the affective and cognitive process, to aggregate subsequently the technical information, looking for the social actions. For this development, beyond studies with origin in energy sector, information of psychology and educational domain was considered, aligning with present Brazilian legislation and educational parametric criteria. The transverse characteristic of this topic, by a contextualized teaching, create favorable conditions to knowledge build in relation to energy and its consumption and, hence, it has potential to promote the sustainable development by citizenship. The present educational model to the energy conservation has the objective to contribute with energy sector, in direction to systematize the contents at fundamental, middle and superior educational levels, starting from effective tools in teaching and learning process, helping teachers in these segments at teach planning. KEYWORDS: Energy conservation, teaching for citizenship, education.
247

Development of a solid state distributed lighting system for rural energy efficient applications

Fritz, Wilfred Leslie Owen January 2006 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2006 / The electrical supply utility, ESKOM, cannot cope with the growing demand in South Africa. This results in load shedding and power outages. This capacity can be augmented, by conducting energy audits, retrofitting government buildings, designing and installing cost-effective lighting systems, and using renewable energy sources in rural areas. Households in rural areas depend on candles and paraffin lamps to supply light at night. Solar panels as renewable energy sources are very expensive in conventional lighting systems. The problem is that a cost-effective, affordable lighting system has not yet been designed. The following four projects have been completed by the author: - Software development for a lighting design in general - Efficient high bright light emitting diode (HB-LED) lighting system - Energy audit and retrofit of the Nuwe Hoop School in Worcester - Optimization of hybrid solar-diesel system Firstly, the author wrote a program that is used in lighting designs. This illumination software is utilized for educational purposes. A manual step-by-step lighting design procedure was compiled. The JAVA object-oriented programming language was used to write the code of the design software. Real life design parameters are fed to the program, to confirm proper implementation. The software package will perform illuminance calculations to display relevant Isolux diagrams for educational purposes.
248

Análise técnico-econômica da utilização de um gerador à gás natural em um sistema de cogeração: estudo de caso

Costa, Adriana Aparecida dos Santos [UNESP] 06 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-06Bitstream added on 2014-06-13T18:59:52Z : No. of bitstreams: 1 costa_aas_me_guara.pdf: 2059273 bytes, checksum: b8ab2fd24ffac7e626369adad28e0f50 (MD5) / Neste trabalho é apresentada uma proposta de sistema de cogeração utilizando motor de combustão interna à gás natural, visando otimizar a utilização da energia primária em um estudo de caso de uma empresa produtora de chapas pré-pintadas. Este grupo moto-gerador foi adquirido para suprir a escassez de energia elétrica no ano de 2001 no Brasil, e hoje tem sua operação inviável economicamente se utilizado somente como gerador. Para isso realizou-se uma auditoria energética na empresa em questão, uma análise do mercado energético atual, da legislação vigente sobre cogeração, da viabilidade técnico-econômica da implementação do sistema proposto, das perspectivas de expansão do parque industrial da empresa e dos aspectos estratégicos no que diz respeito a diversificação na obtenção da energia elétrica. Estudou-se também as características do sistema elétrico existente e as características dos equipamentos responsáveis pela geração de energia térmica. O estudo realizado buscou propor a melhor forma de utilização do grupo moto-gerador, com o menor impacto no sistema elétrico atual e sem prejuízos para o processo de produção. Os resultados deste trabalho convergiram para um sistema de cogeração compacto que melhor se adaptou às particularidades da empresa estudada. Além da vantagem financeira que este trabalho constatou, também existem vantagens técnicas e estratégicas. Assim sendo, este trabalho proporciona o suporte técnico necessário para a tomada de decisões de como melhor aproveitar o potencial energético do equipamento adquirido pela empresa em questão e para outras empresas que apresentam um panorama semelhante. / In this work is presented a proposal of a cogeneration system using internal combustion engine using natural gas, with the objective to improve the employment of the primary energy in the case study in a manufacturer company of pre-painted metallic sheets. This moto-generation group was acquired in 2001 in order to supply the lack of providing of the electrical energy that Brazil confronted in the same year and now its utilization is not economic feasibility. An energetic audit has been carried out in the industry, an analysis of current energy market, the rules cogeneration's legislation, a technical economic feasibility of the cogeneration system proposed an analysis regarding the company's expansion plan and the flexibility for supplying energy of the other sources. This work also analysed the existent electrical system and the characteristics of the equipment responsible for the thermal energy generation. This work has focused on a better utilization of the moto-generation group with a minimum number of changes in the electrical system and without causing any disturbance damages for the manufacture's production process. The results of this work indicated that a compact cogeneration system is the best solution considering the characteristics of the enterprise studied. Besides the financial advantages verified, there are technical and strategic advantages. So, this work will give technical support for decisions about the best advantage the energetic potential of the equipment acquired by company in matter and for other companies that present a similar panorama.
249

Application of Passive Design Strategies for New Low-income Affordable Housing Developments in San Pedro Sula, Honduras

Fernandez, Michell Verenisse, Fernandez, Michell Verenisse January 2017 (has links)
Honduras faces the highest levels of economic inequality in Latin America, 66% of the population live in poverty, 8.1% is the unemployment rate and 1.1 million the housing deficit. One million affordable housing units need to be built to cover the shortfall, which is concentrated mainly in Tegucigalpa, San Pedro Sula and Choloma. Building at least half a million new homes and improving about 600,000 that do not meet the minimum conditions of habitability is what is needed in Honduras, particularly in the cities of San Pedro Sula and Tegucigalpa is required. In Honduras, the government has the goal to massify new low-income affordable housing developments around cities, with an estimated 12,000 new households to be constructed across Honduras by the end of 2018. But as in most developing countries, sustainable design is not taken into consideration when it comes to affordable housing developments, yet low income-families are highly affected from increasing energy prices and environmentally related health issues. These large-scale projects could minimize local and global environmental impacts and improve the quality of life of its inhabitants, if sustainable guiding standards are embraced during design, construction, and maintenance. The rising cost of utilities are affecting low-income families in “affordable” housing developments, the energy expenses force them to make hard choices between basic needs or going back to informal settlements. For this reason, reducing operating and maintenance cost should be a priority for low-income housing design Passive design is any technology or strategy that increase energy-efficiency and thermal comfort by taking advantage of the climate, without the need for expensive mechanical systems. The study analyses different passive design strategies that are applicable for affordable housing developments. Such strategies are orientation, shading, natural ventilation, daylight, and open spaces. The aim is to address energy efficiency and thermal comfort by evaluating and suggesting solutions that improve the quality of life of low-income families in affordable housing developments. The application of passive design strategies showed a 44% reduction in electric utilities, a base case and a proposed design was modeled in eQuest, energy modeling software. The results show a significant reduction towards low-income families’ housing expenses.
250

Energy conservation in urban planning : An ecological approach towards the development of more energy efficient urban patterns

Kadi, H. E. January 1988 (has links)
No description available.

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