This study explores ways to determine the energy efficiency of a pyrometallurgical ore reduction plant and measures to improve it. The feasibility of building a commercial plant - that is more energy efficient, has a low energy cost, and can operate independently and cost-effectively of external electricity supply - is determined. The need for energy efficiency is expanded to three questions: how should the energy efficiency of the plant be determined, what is the efficiency of the existing plant and to what level it can be improved. Literature and other relevant sources were consulted. Twenty potential energy conservation measures were identified through a literature study. A multi-criteria decision-making approach resulted in the selection of ten measures for conceptual implementation. The measures ranged from high-efficiency motors, solar power, heat recovery with thermal oil and various heat engines, to pressure recovery with turbo-generators. A case study approach was followed with the energy efficiency of an existing prototype plant the subject being studied. The energy usage of the existing plant and feasible measures to improve the performance were empirically observed. The impact of these measures was modelled and the results of the conceptual implementation determined. Two measures that were implemented during the study are also described and the results reported. The study found that the energy efficiency of the plant could be determined by the ratio of product exergy to input energy. By incorporating a number of energy conservation measures conceptually the internal efficiency of the prototype plant was conceptually improved from the current 17% to 22% and as a result externally supplied electricity reduced by 47%. The results were extrapolated to a future commercial plant and energy efficiencies of 26% on-grid and 21% off-grid predicted. This study suggests that a significant improvement in energy efficiency and energy cost can be achieved by integrating appropriate energy conservation measures into the existing and future plants. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

The present research has investigated the problem of energy management and conservation in the Hotel sector of Cyprus; one of the most important and most dynamic sectors of the island's economy. The methodology of the soft systems approach was considered as the most appropriate method for tackling the complexities involved in the problem situation. The outcome of the research demonstrated that the adoption of this methodology is suitable for investigating problems of energy management and conservation and can indeed be extended by use of "systemic" interactive computer simulation methods. The existing problem situation in the Hotel industry was investigated through design and execution of questionnaires addressed to the main human actors, energy audits, site visits, discussions and statistical analysis of energy related factors. Serious deficiencies were found at all levels. Energy consumption and use patterns were analysed with respect to quantity, quality and timing of energy use. Existing and new technologies were evaluated using life cycle cost-effective analysis methods. Evaluation of alternative energy supply "mixes" using computer simulation techniques were made, which demonstrated the viability of cogeneration, wind and solar collection approaches in some situations. The research concluded that: (a) there is good scope for energy conservation (in the range of 10-20%) by modifying user habits, hotel energy demand, remodeling of existing technology and introduction of new energy efficient technology. (b) there is an immediate need to provide training and education to all human factors involved. (c) there is a need to modify existing energy-policies. (d) there is need to introduce new energy management infrastructure at National level and below. (e) there is real need for changing the attitudes towards energy conservation of all "actors" involved. (f) there is need for further investigation of the energy supply and demand patterns of hotels. Recommendations concerning the introduction of training and education, and changes in policy, attitudes, practice and energy use, and infrastructure are made. All recommendations are based on conceptual models developed following the application of the soft systems methodology.

Klimato kaita yra prioritetinė pasaulio, Europos Sąjungos ir atskirų šalių problema. Į klimato kaitos iššūkius atsakyti galima dviem būdais – mažinant paklausą ir didinant naujų bei atsinaujinančių energijos šaltinių santykinę dalį. Tyrimų duomenimis namų ūkiuose slypi didelis energijos taupymo potencialas. Efektyvus energijos vartojimas vestų į klimato kaitos įsipareigojimų įgyvendinimą, taipogi galėtų apčiuopiamai mažinti namų ūkių sąskaitas už energiją, tiesiogiai gerinti kasdienį kiekvieno piliečio gyvenimą Darbo tikslas- įvertinti klimato kaitos švelninimo priemones namų ūkiuose Lietuvoje Darbo tikslui pasiekti buvo išsikelti tokie uždaviniai:  Apžvelgti klimato kaitos švelninimo politikos įgyvendinimą tarptautiniu lygmeniu.  Nustatyti namų ūkių svarbą klimato kaitos švelninimo politikos tikslų įgyvendinimui.  Pateikti Lietuvos šiltnamio dujų emisijų ir galutinės energijos suvartojimo namų ūkių sektoriuje lyginamąją analizę;  Išnagrinėti šiltnamio dujų emisijų namų ūkiuose mažinimo priemones Lietuvoje ir palyginti su taikomomis kitose šalyse;  Ištirti šiltnamio dujų mažinimo galimybes Lietuvos namų ūkiuose, keičiant gyventojų įpročius ir taupant energiją. Atlikus energijos suvartojimo, šiltnamio efektą sukeliančių dujų emisijų kitimo ir klimato kaitos švelninimo politikos Lietuvoje analizę, gavome, kad Lietuvoje namų ūkiuose yra suvartojama sąlyginai daug galutinės energijos ir išskiriama šiltnamio dujų. Atlikus empirinį tyrimą... [toliau žr. visą tekstą] / Climate change is considered as one of the most important problems in the whole world, EU and separate countries. The challenges of climate change can be overcome in two ways – decreasing the demand and increasing the part of the energy that is created by new and renewable energy recourses. According to the previous researches, there is a great energy saving potential in the households. This means that more efficient energy consumption would lead to better implementation of climate change requirements as well as smaller households’ energy bills and thus improvement of daily life of every person. The object of the paper – Climate change mitigation measures in households. The purpose of the paper – To assess climate change mitigation measures in Lithuanian households. Objectives of the paper:  To give the overview of implementation of climate change mitigation policies in the international aspect.  To determine the influence of households in implementing climate change mitigation policy.  To provide the comparative analysis of GHG emissions and energy consumption in Lithuanian households.  To analyze the measures for mitigating GHG emissions in Lithuania and to compare it with other measures used in different countries.  To estimate the possibilities of mitigating GHG emissions in Lithuanian households while changing their behavior and saving more energy. After conducting the analysis of energy consumption, GHG emissions pattern and... [to full text]

Modern offices are crowded with personal computers. While studies have shown these to be idle most of the time, they remain powered, consuming up to 60% of their peak power. Hardware based solutions engendered by PC vendors (e.g., low power states, Wake-on-LAN) have proven unsuccessful because, in spite of user inactivity, these machines often need to remain network active in support of background applications that maintain network presence. Recent solutions have been proposed that perform consolidation of idle desktop virtual machines. However, desktop VMs are often large requiring gigabytes of memory. Consolidating such VMs, creates large network transfers lasting in the order of minutes, and utilizes server memory inefficiently. When multiple VMs migrate simultaneously, each VM’s experienced migration latency grows, and this limits the use of VM consolidation to environments in which only a few daily migrations are expected per VM. This thesis introduces partial VM migration, an approach that transparently migrates only the working set of an idle VM, by migrating memory pages on-demand. It creates a partial replica of the desktop VM on the consolidation server by copying only VM metadata, and transferring pages to the server, as the VM accesses them. This approach places desktop PCs in low power state when inactive and resumes them to running state when pages are needed by the VM running on the consolidation server. Jettison, our software prototype of partial VM migration for off-the-shelf PCs, can deliver 78% to 91% energy savings during idle periods lasting more than an hour, while providing low migration latencies of about 4 seconds, and migrating minimal state that is under an order of magnitude of the VM’s memory footprint. In shorter idle periods of up to thirty minutes, Jettison delivers savings of 7% to 31%. We present two approaches that increase energy savings attained with partial VM migration, especially in short idle periods. The first, Context-Aware Selective Resume, expedites PC resume and suspend cycle times by supplying a context identifier at desktop resume, and initializing only devices and code that are relevant to the context. CAESAR, the Context-Aware Selective Resume framework, enables applications to register context vectors that are invoked when the desktop is resumed with matching context. CAESAR increases energy savings in short periods of five minutes to an hour by up to 66%. The second approach, the low power page cache, embeds network accessible low power hardware in the PC, to enable serving of pages to the consolidation server, while the PC is in low power state. We show that Oasis, our prototype page cache, addresses the shortcomings of energy-oriented on-demand page migration by increasing energy savings, especially during short idle periods. In periods of up to an hour, Oasis increases savings by up to twenty times.

Modern offices are crowded with personal computers. While studies have shown these to be idle most of the time, they remain powered, consuming up to 60% of their peak power. Hardware based solutions engendered by PC vendors (e.g., low power states, Wake-on-LAN) have proven unsuccessful because, in spite of user inactivity, these machines often need to remain network active in support of background applications that maintain network presence. Recent solutions have been proposed that perform consolidation of idle desktop virtual machines. However, desktop VMs are often large requiring gigabytes of memory. Consolidating such VMs, creates large network transfers lasting in the order of minutes, and utilizes server memory inefficiently. When multiple VMs migrate simultaneously, each VM’s experienced migration latency grows, and this limits the use of VM consolidation to environments in which only a few daily migrations are expected per VM. This thesis introduces partial VM migration, an approach that transparently migrates only the working set of an idle VM, by migrating memory pages on-demand. It creates a partial replica of the desktop VM on the consolidation server by copying only VM metadata, and transferring pages to the server, as the VM accesses them. This approach places desktop PCs in low power state when inactive and resumes them to running state when pages are needed by the VM running on the consolidation server. Jettison, our software prototype of partial VM migration for off-the-shelf PCs, can deliver 78% to 91% energy savings during idle periods lasting more than an hour, while providing low migration latencies of about 4 seconds, and migrating minimal state that is under an order of magnitude of the VM’s memory footprint. In shorter idle periods of up to thirty minutes, Jettison delivers savings of 7% to 31%. We present two approaches that increase energy savings attained with partial VM migration, especially in short idle periods. The first, Context-Aware Selective Resume, expedites PC resume and suspend cycle times by supplying a context identifier at desktop resume, and initializing only devices and code that are relevant to the context. CAESAR, the Context-Aware Selective Resume framework, enables applications to register context vectors that are invoked when the desktop is resumed with matching context. CAESAR increases energy savings in short periods of five minutes to an hour by up to 66%. The second approach, the low power page cache, embeds network accessible low power hardware in the PC, to enable serving of pages to the consolidation server, while the PC is in low power state. We show that Oasis, our prototype page cache, addresses the shortcomings of energy-oriented on-demand page migration by increasing energy savings, especially during short idle periods. In periods of up to an hour, Oasis increases savings by up to twenty times.

Bibliography: p. 133-144. / x, 170 p. : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis investigates the impact on residential energy use for climate control or urban design variables, such as building density, spacing and orientation. Energy use for heating/cooling is predicted in a range of urban configurations that are compatible with the following objectives: wind shelter and solar access in winter and urban ventilation and shading in summer. / Thesis (Ph.D.)--University of Adelaide, Dept. of Architecture, 1997?

Thesis (Ph.D.)--University of Melbourne, 1999. / "14 October 1999." Includes bibliographical references (leaves 343-370).

Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Hsien-Hsin Sean Lee; Committee Member: Abhijit Chatterjee; Committee Member: Bernard Kippelen; Committee Member: Gabriel H. Loh; Committee Member: SungKyu Lim.

Thesis (Ph. D. in Psychology)--Vanderbilt University, Aug. 2009. / Title from title screen. Includes bibliographical references.

Thesis (B.A.)--Haverford College, Dept. of Political Science, 2009. / Includes bibliographical references.