In recent years there has been an increasing trend in the provision of central heating and split vapour compression air conditioning systems to domestic dwellings in Cyprus. To minimise their economic and environmental impact, this study examines the feasibility and economic viability of energy conservation measures and the feasibility of the application of solar driven LiBr-water absorption system for space conditioning. Initially, the study compares through simulation, the heating and cooling requirements of domestic dwellings constructed in Cyprus during the last century. The simulations required values for the thermal conductivity of local building materials, like the hollow brick and mud and straw block. These were not available, and measurements were performed on a machine specifically purchased for the project to establish these values for the first time. These material properties will be of value to building services engineers in Cyprus and the Middle East for the more precise determination of building heating and cooling loads. Evaluation of the internal conditions resulting from the various types of constructions indicated that the traditional and insulated modem houses, could maintain indoor temperature in winter between 16°C and 20°C, but in the summer temperatures exceeded 36°C. The use of natural and mechanical ventilation could reduce slightly the maximum indoor summertime temperatures, but not to a level that could provide thermal comfort. Window gains are an important factor in domestic building energy requirements, and significant savings can result when extra measures are taken. The savings in cooling energy demand for a well-insulated house may be as high as 24% when low-emissivity double glazed windows are used compared to clear double glazed windows giving a pay-back period of 3.8 years. Other factors investigated are the effect of overhangs, shape and orientation of buildings and thermal mass. The results show that the roof is the most important structural element of domestic dwellings in the Cypriot environment. For good thermal performance, the roof must offer a discharge time of 6 hours or more and have a thermal conductivity of less than 0.48 W/m-K. Life cycle cost analysis has shown that measures that increase the roof insulation pay back in a short period of time, between 3.5 to 5 years. However, measures taken to increase wall insulation pay back in a longer period of time, approximately 10 years. The only natural energy resource abundantly available in Cyprus is solar energy, which could be used to power a low energy active cooling system based on the absorption cycle. To facilitate investigation of the feasibility of the application of solar driven absorption systems for domestic cooling, a 1 kW LiBr-water absorption-cooling unit was designed and constructed. The unit was used to determine experimentally the heat and mass transfer coefficients in the heat exchangers of absorption systems. In certain cases these were found to differ considerably from values obtained from heat and mass transfer correlations published by other investigators. The experimentally determined heat and mass transfer coefficients were employed in the design and costing of an 11 kW cooling capacity solar driven absorption cooling machine which, from simulations, was found to have sufficient capacity to satisfy the cooling needs of a well insulated domestic dwelling. Economic analysis has shown that for such a system to be economically competitive compared to conventional cooling systems its capital cost should be below C£ 2000. This drawback can be balanced by a lower total equivalent warming impact being 2.7 times smaller compared to conventional cooling systems.

Thesis (M.P.A.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 133-137).

Thesis (M.P.A.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 133-137). Also available in print.

The idea that we can 'save energy' has become a commonplace homily. But with a moment's reflection it is clear there is nothing self-evident about saving energy. Do we save fuel or a system's ability to 'do work'? Do we conserve for perpetuity or to prolong use? Is the motivation resource economy, scarcity, productivity, or - more recently - climate change mitigation? And what stops the fruits of individual parsimony being consumed elsewhere? This thesis offers a history of the idea that we can conserve energy by using it more efficiently. In recounting this story, it is argued that conserved energy is a 'metrological resource' produced by practices of measurement, calculation, and computation. A second argument is that the history of ERC offers an under examined example of a 'resource ontology'; the social processes through which nature is imbued with utility and value. Accordingly, the study of, what is termed, energy resource conservation (ERC herein) involved a novel research method which focused upon the scientific and intellectual processes of resource making, as much as the material. This thesis begins in 1865 with the publication of William Jevons' The Coal Question (1865), in which the resource conservative principles of Classical political economy were overturned. Jevons argued that increased efficiency of coal use would serve only to increase the rate and scale with which coal was used. Proceeding from this anti-thesis, the following chapters outline how, irrespective of Jevons' claim, policies based on the principles of scientific management were applied to the conservation of fuel resources for conserving natural resources. In pre-war America, a complex system of 'pro-rationing' extraction licenses were introduced to conserve the productive capacity of petroleum wells. However, a significant shift occurred during the Cold War, as the conservation of fuel became increasingly conflated with the econometrician's notion of efficient resource allocation. But the most significant developments occurred in the nineteen-seventies, in response to a perceived crisis in energy supply. Fuel policy became a more systemic 'energy policy', which drew on scientific management, graph theory, systems theory, statistical mechanics, and computational econometrics in an attempt to quantify and demonstrate how society could act to conserve energy resources by increasing the efficiency of energy use. The resulting science, and its concomitant policies were an odd mix of cold war rational decision making theories, détente science, scientific radicalism, and liberal economic theory, all given a countercultural and environmentalist gloss in the latter half of the decade. On the basis of this conflation of ideas, a new approach to energy saving that emerged, which transformed the principles of energy resource governance, shifting the onus to conserve from producer to consumer, with distinct implications for post-war theories of political economy.

Creating a diverse and flexible energy system to ensure security of supply is at the heart of UK energy policy. However, despite the apparent interest in the idea of securing supply in this way and the term ‘diversity' becoming more frequently used in this context in government White Papers, policy discourse and the academic literature relatively little attention has been given to exploring what diversity means, how it can be measured, what contribution it can make to different policy objectives and the specific implications for the UK electricity system. Furthermore CCS technologies which are becoming increasingly important to decarbonisation of the power sector in order to meet legally binding greenhouse gas targets set out in the Climate Change Act which raises the question, what are the potential impacts of these technologies on the diversity of the future UK electricity system? To answer this question a mixed methodology of quantitative energy-economic modelling (using MARKAL), scenario analysis and diversity analysis is combined with qualitative semi-structured stakeholder interviews. Data analysis is carried out in two parts. The first assesses the diversity (with a specific focus on the effect of different input assumptions on CCS technologies) of the scenarios generated using Stirling's Diversity Heuristic and creates a set of ‘diversity profiles' which map changes in diversity across each scenario. The second part uses stakeholder perspectives to inform the quantification of diversity across the same set of scenarios providing evidence of the impact of different stakeholder perspectives on the overall diversity of the electricity system.

Thesis (M.Sc.)--Lund University, 2001. / Title from title screen of PDF file (viewed 9 Dec. 2003). Includes bibliographical references.

Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-10-11T13:53:16Z No. of bitstreams: 1 DissRPS.pdf: 5427794 bytes, checksum: c1626fcdcaf2b48b6a76b63021220431 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T12:12:21Z (GMT) No. of bitstreams: 1 DissRPS.pdf: 5427794 bytes, checksum: c1626fcdcaf2b48b6a76b63021220431 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-21T12:12:28Z (GMT) No. of bitstreams: 1 DissRPS.pdf: 5427794 bytes, checksum: c1626fcdcaf2b48b6a76b63021220431 (MD5) / Made available in DSpace on 2016-10-21T12:12:34Z (GMT). No. of bitstreams: 1 DissRPS.pdf: 5427794 bytes, checksum: c1626fcdcaf2b48b6a76b63021220431 (MD5) Previous issue date: 2016-08-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / This study aims to propose a didactic sequence involving the use of resources and diversified activities applied to the teaching of Conservation of Mechanical Energy and its applications. The didactic sequence was based on the Theory of Meaningful Learning and the idea of concept maps, taking into consideration the principles and present steps in Potentially Meaningful Teaching Units (PMTU). In the didactic sequence of concepts approach is through reading popular science short texts involving different contexts and applications, through an animation and a computer simulation, using questionnaires, including a mathematical formalization, and the use of conceptual maps. The elaborate didactic sequence was implemented in a class of 1 st year of high school, in a private school in the city of Ribeirão Preto, SP. In general, the application of the teaching sequence obtained good results. In addition to satisfactory learning outcomes, it was noticed the involvement of students in the proposed activities, showing satisfied with the dynamics of classes, and even explaining that they facilitated the understanding of the study content, especially those involving conceptual and computing resources maps. From the results, it is understood that the educational product developed, a didactic sequence guided by the idea of PMTU, has a potential in terms of promoting the learning of mechanical energy conservation concepts can be implemented in other contexts. / Este trabalho tem por finalidade propor uma sequência didática envolvendo o uso de recursos e atividades diversificadas aplicadas ao ensino da Conservação da Energia Mecânica e suas aplicações. A sequência didática foi norteada pela Teoria da Aprendizagem Significativa e pela ideia de Mapas Conceituais, considerando ainda os princípios e passos presentes nas Unidades de Ensino Potencialmente Significativa (UEPS). Na sequência didática, a abordagem dos conceitos se dá através da leitura de textos curtos de divulgação científica envolvendo diferentes contextos e aplicações, através de uma animação e de uma simulação computacional, com o uso de questionários, incluindo uma formalização matemática, além do uso de mapas conceituais. A sequência didática elaborada foi implementada em uma turma de 1o ano do Ensino Médio, em uma escola privada na cidade de Ribeirão Preto, SP. De um modo geral, a aplicação da Sequência Didática obteve bons resultados. Além de resultados satisfatórios de aprendizagem, foi perceptível o envolvimento dos alunos nas atividades propostas, mostrando-se satisfeitos com a dinâmica das aulas e inclusive explicitando que estas facilitaram o entendimento do conteúdo estudado, especialmente as que envolviam mapas conceituais e recursos computacionais. A partir dos resultados obtidos, compreende-se que o produto educacional elaborado, uma sequência didática orientada pela ideia de UEPS, possui um potencial em termos de promoção da aprendizagem dos conceitos de conservação de energia mecânica, podendo ser implementada em outros contextos.

This diploma thesis is dedicated to the analysis of operating data from the Brewery, a former industrial building, which has been reconstructed to a student centre of the Faculty of Information Technologies. The main goal of the work was to analyze the performance of the building and to evaluate energy savings originating from the energy saving measures that were applied during the retrofit.. The first part of the thesis focuses on the particular energy saving measures and the predictions of energy savings. The second part presents the results of the monitoring of the building and the HVAC systems during the first year of the operation of the Brewery.

Continuous improvements to the state of the art have made it easier to create, send and receive vast quantities of video over the Internet. Catalysed by these developments, video is now the largest, and fastest growing type of traffic on modern IP networks. In 2015, video was responsible for 70% of all traffic on the Internet, with an compound annual growth rate of 27%. On the other hand, concerns about the growing energy consumption of ICT in general, continue to rise. It is not surprising that there is a significant energy cost associated with these extensive video usage patterns. In this thesis, I examine the energy consumption of typical video configurations during decoding (playback) and encoding through empirical measurements on an experimental test-bed. I then make extrapolations to a global scale to show the opportunity for significant energy savings, achievable by simple modifications to these video configurations. Based on insights gained from these measurements, I propose a novel, energy-aware Quality of Experience (QoE) metric for digital video - the Energy - Video Quality Index (EnVI). Then, I present and evaluate vEQ-benchmark, a benchmarking and measurement tool for the purpose of generating EnVI scores. The tool enables fine-grained resource-usage analyses on video playback systems, and facilitates the creation of statistical models of power usage for these systems. I propose GreenDASH, an energy-aware extension of the existing Dynamic Adaptive Streaming over HTTP standard (DASH). GreenDASH incorporates relevant energy-usage and video quality information into the existing standard. It could enable dynamic, energy-aware adaptation for video in response to energy-usage and user ‘green' preferences. I also evaluate the subjective perception of such energy-aware, adaptive video streaming by means of a user study featuring 36 participants. I examine how video may be adapted to save energy without a significant impact on the Quality of Experience of these users. In summary, this thesis highlights the significant opportunities for energy savings if Internet users gain an awareness about their energy usage, and presents a technical discussion how this can be achieved by straightforward extensions to the current state of the art.

Made available in DSpace on 2018-06-27T19:13:33Z (GMT). No. of bitstreams: 3 Vinicius Bisognin.pdf: 3237197 bytes, checksum: d5213702c8f66050cb6fb6af982a3d09 (MD5) Vinicius Bisognin.pdf.txt: 117183 bytes, checksum: 408acfe12278db4be967a0514d2f4607 (MD5) Vinicius Bisognin.pdf.jpg: 3397 bytes, checksum: e96b2dd1373c87f056e7bc7925ef4a54 (MD5) Previous issue date: 2014-04-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Computational resources have been identified as important auxiliary teaching, in view of the current technological developments. Thus, the purpose of this study demand through the use of computational simulations and animations to provide high school students an understanding of the more general principle of Conservation of Mechanical Energy. Learning activities with the use of computational simulations and animations are structured according to the methodology of Three Pedagogical Moments (TMP) and will make use of a Blog as a Virtual Learning Environment (VLE) to provide greater interaction between students and teacher and between them and the simulations and animations. It is expected that the learning of physics concepts involved in the subject of Mechanical Energy Conservation is enhanced. / Os recursos computacionais têm sido apontados como importantes auxiliares do ensino, tendo em vista a evolução tecnológica atual. Desta forma, a proposta desse trabalho procura através da utilização de simulações e animações computacionais proporcionar aos estudantes de Ensino Médio uma compreensão mais generalizada do princípio da Conservação de Energia Mecânica. As atividades de aprendizagem com o uso das simulações e animações computacionais estão estruturadas de acordo com a metodologia dos Três Momentos Pedagógicos (TMP) e farão uso de um Blog como Ambiente Virtual de Aprendizagem (AVA) para proporcionar maior interação entre os estudantes e o professor e entre eles e as simulações e animações. Espera-se que a aprendizagem dos conceitos físicos envolvidos no tema Conservação de Energia Mecânica seja potencializada.