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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.
421

Energy management in the South African hotel industry

Fouejio-Tsobze, Brice January 2010 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2010. / In recent years, the South African hotel industry has experienced increasing demand for hotel's services. At the same time, mounting costs of energy affects energy performance and public image. Energy management is a new approach to address those widespread problems. This study aimed to suggest good management practices and develop a "self-help" approach, to reduce the demand and costs of energy for the South Africa hotel industry. This is expected to result in monetary savings and conservation of energy resources. This has been done by conducting survey within seven selected hotels in Cape Town, metropolitan of South Africa. In addition, through the "self-help" guide, approaches to energy management system are also described, showing the ways for hotels to achieve better energy performance. Potentials for savings from good housekeeping are estimated to 10 - 15%. The "self-help" guide is recommended to be improved through implementation in pilot hotels; and the proposal set of benchmarks need to be different for hotels in different provinces of South Africa considering the differences in climate conditions. The result of this study range from presenting the energy conservation awareness, barriers, method of conservation, financial and institution mechanisms, policy measures, status of energy use and propose strategy to develop a "Self-help" guide for energy management in South African Hotel industry. It has been found that energy monitoring has been done in the South African Cape Town hotels. From the total energy consumed by this industry, electricity accounts 80% of it of which air conditioning takes the biggest share (about 50%) and the remaining for Liquefied Petroleum Gas (LPG), diesel and others fuels. In addition, through the "self-help" guide, approaches to energy management system are also described, showing the ways for hotels to achieve better energy performance. Potentials for savings from good housekeeping are estimated to 10 - 15%. The "self-help" guide is recommended to be improved through implementation in pilot hotels; and the proposal set of benchmarks need to be different for hotels in different provinces of South Africa considering the differences in climate conditions.
422

Retrofitting to lower energy consumption: comparing two commercial buildings in Sandton, Johannesburg

Thovhakale, Takalani Bridget 20 August 2012 (has links)
M.Sc. / This study compares the electricity consumption of two buildings, of similar architectural design, in Simba Office Park, Sandton, in Johannesburg. One of the buildings (Block AB) has not been retrofitted for energy efficiency, whilst the other building (Block C) is a retrofitted building. The hypothesis postulates that the retrofitted building would use less energy than the non-retrofitted one. The research methodology employed has been used internationally, as in the case reported by Levine et al. (1996), who did a study in the United States of America on retrofitting for achieving energy efficiency. Dong et al. (2005) investigated the energy savings due to the retrofitting of old Singaporean commercial office buildings. In this case, six buildings were compared before and after retrofitting, using utility bill and weather data. There have also been similar studies in China (Xu et al, 2006) and Budapest (Urge-Vorsatz & Novikova, 2008). The Budapest study also unpacked the cost of retrofitting. Using methods advocated by Probst (2004), Yalcintas (2008) and Yalcintas & Kaya (2009) for collecting data on floor space, building parameters and design, this study also collected electricity consumption data based on meter readings for the same blocks over the period March 2009 to April 2010. The retrofitting measures were documented and the associated costs noted. Interviews were conducted with key personnel such as the Central Energy Fund (CEF) House executives, the site electrical engineer, the developer, and Simba Office Park managers. Block AB had the least number of energy-efficient installations. Block C was found to be fully retrofitted, at a cost of more than R4 million. However, the energy management system, required to manage and monitor energy use, was only fully installed by November 2009. The results of this study are significant. It was found that energy consumption for Block C far exceeded that for Block AB. Thus, in this case, retrofitting did not reduce electricity consumption. The results demonstrate that in order to fully understand energy use, data collection and analysis must be ongoing. This verifies the findings of Ali (2008), Armstrong (2009) and Yalcintas & Kaya (2009) who found that we need to shift from managing buildings to managing energy use and assess and verify any recorded savings to ensure energy conservation. Computer-based building management systems play a major role in such management. Such a system was only partially in use in Block C for the duration of the study period. Thus, another finding was that the energy management system needs to be fully operational in real time, or else energy efficiencies cannot be achieved and data sets will be incomplete. This conclusion reflects the findings of Hirst (1980).
423

Energy Efficiency and Conservation Attitudes: An Exploration of a Landscape of Choices

McClaren, Mersiha Spahic 27 February 2015 (has links)
This study explored energy-related attitudes and energy-saving behaviors that are no- or low-cost and relatively simple to perform. This study relied on two data sources: a longitudinal but cross-sectional survey of 4,102 U.S. residents (five biennial waves of this survey were conducted from 2002 to 2010) and a 2010 cross-sectional survey of 2,000 California residents. These two surveys contained data on two no- and low-cost behaviors: changing thermostat setting to save energy (no-cost behavior) and CFL installation behavior (low-cost behavior). In terms of attitudes, two attitudinal measures emerged from these data following a Cronbach's alpha and Confirmatory Factor Analysis (CFA): the pro-environmental attitude and concern for the energy use in the U.S. society. These two attitudes, along with other socio-demographic and external factors (home ownership, weather, price of energy, etc.), were examined to assess whether attitude-behavior relationships persisted over time, were more prominent across certain groups, or were constrained by income or other socio-demographic factors. Three theoretical viewpoints of how attitudes may relate to behavior guided the analysis on how attitudes and contextual factors may inter-relate either directly or through a moderator variable to affect thermostat-setting and CFL installation behavior. Results from these analyses revealed four important patterns. First, a relationship between the pro-environmental attitude and the two behaviors (thermostat-setting and CFL installation behavior) was weak but persistent across time. Second, financial factors such as income moderated the pro-environmental attitude and CFL installation relationship, indicating that the pro-environmental attitude could influence the behavior in those situations where financial resources are sufficient to comfortably allow the consumer to participate. Third, this study documented that most people reported changing thermostat settings to save energy or having one or more CFLs in their homes. This finding suggests that organizations, policy makers, or energy efficiency program administrators may want to assess whether they should pursue these two behaviors further, since they appear to be very common in the U.S. population. Last, this study showed that thermostat-setting and CFL installation behavior have multi-factorial influences; many factors in addition to attitudes were significantly associated with these behaviors, and all these factors together explained no more than 16% of behavioral variance. This suggested that if energy-saving behaviors are a function of many different variables, of which none appear to be the "silver bullet" in explaining the behaviors (as noted in this study), then policy analysis should explore a broader number of causal pathways and entertain a wider range of interventions to influence consumers to save energy.
424

Energy comparison of hot and cold beef processing

Nason, Peggy Gilliam. January 1979 (has links)
Call number: LD2668 .T4 1979 N368 / Master of Science
425

Effects of swine farrowing house air and mineral nutrition on Cucumis sativus, L.

Long, John Edward. January 1979 (has links)
Call number: LD2668 .T4 1979 L65 / Master of Science
426

Carburetion system for biomass gas fueling of spark ignition engines

Goodman, Mark A. January 1984 (has links)
Call number: LD2668 .T4 1984 G666 / Master of Science
427

Evaluation of a gear selection aid for fuel efficient tractor operation

Blumanhourst, Michael B. January 1984 (has links)
Call number: LD2668 .T4 1984 B58 / Master of Science
428

Environmental Natural Processes that Achieve Thermal Comfort in Multifamily Buildings in Hot Arid Regions

Moreno, Paola January 2015 (has links)
Buildings, especially in hot climates, consume a lot of energy when people want to be comfortable inside them, which translates to very expensive fees each month. The most innovative response to this problem is renewable energy, that is used, in this case, to run mechanical HVAC systems. Renewable energy is the solution for many problems, but to avoid urban heat islands when using excessive HVAC systems (powered by renewables), and to solve thermal comfort-related problems, there has to be other solution. The major challenge to find it would be to have a change of thinking process. If a building in a hot-arid region uses natural processes to emulate the functions of HVAC systems, and the proper passive strategies, then, it will provide thermal comfort to its users, diminishing the need of a mechanical system. This hypothesis will be carried out by extracting the natural processes found in a specific case in nature, applying them into a building's design, and then simulating its energy efficiency with the adequate software. There will be a comparison of the same proposed building without the natural processes, to have tangible numbers showing that these proposed strategies, in fact, work. With explanatory detailed diagrams and the energy analysis, the hypothesis could be proven correct or incorrect. The significance of this approach relies on the proximity to the natural processes that have been working in different aspects of life since the beginning of time. They have been there all the time, waiting until architects, engineers, and people in general use them, instead of making more new energy-using inventions. By having the numbers from a conventional building and the ones of the proposed building, and the right environmental diagrams, the experiment should be valid. In the near future, there should be more research focused on nature and its processes, in order to be able to reduce the use of mechanical systems, and with that, reduce the energy use and the carbon footprint.
429

Energy Renovation of an Historic Town Using Life Cycle Cost Optimization : An Assessment of Primary Energy Use and CO2 Emissions / Energirenovering av en historisk stad genom livscykelkostnadsoptimering : En utvärdering av primärenergianvändning och CO2-utsläpp

Milić, Vlatko January 2016 (has links)
Historic buildings, buildings built before 1945, represent a third of the total building stock in Sweden. While implementing energy efficiency measures (EEMs) on historic buildings it is important to consider heritage values. This thesis aims to investigate impacts on primary energy use and CO2 emissions while using life cycle cost (LCC) optimization on historic buildings in three studied cases: reference case with no implemented EEMs (case 1), lowest possible LCC (case 2) and a decrease by 50% in energy use (case 3). As a case study 920 historic buildings divided into twelve typical buildings (6 wood buildings, 1w-6w, and 6 stone buildings, 1s-6s) in the downtown area of Visby, Sweden, are used. Within the scope of the thesis, how to achieve the most profitable EEMs and how the profitability of energy renovation varies between the typical buildings in the studied cases will be analyzed also. An interdisciplinary method is applied in the thesis that considers both heritage values and energy savings. However, the keystone of the thesis is the use of the program Optimal Energy Retrofit Advisory-Mixed Integer Linear Programming (OPERA-MILP), which is a part of the interdisciplinary method. With the use of OPERA-MILP, the cost-optimal energy renovation strategy is obtained for a building. The program takes into account all energy-related investment costs, as well as the investment and operation costs for the heating system, during a set time period. The results show unique packages of EEMs for each of the twelve typical buildings with a potential to lower the total LCC by between 4-11% in the building stock and simultaneously decrease the energy use by more than 50%. The thesis also shows a possible decrease in primary energy use from 24%-57%. The CO2 emissions vary significantly depending on what assumptions are made related to electricity production and biomass use; the results show increases up to 224% in CO2 emissions but also decreases up to 85%. All typical buildings are economically viable to energy renovate. The LCC savings are between 1.4-11.8 SEK with a life cycle set to 50 years for every annually saved kWh, except for case 3 where cost is incurred for every annually saved kWh, 10.0-17.2 SEK, for a number of the typical buildings. / Historiska byggnader, byggnader uppförda före 1945, utgör en tredjedel av det totala byggnadsbeståndet i Sverige. Historiska byggnader har ofta kulturhistoriska värden som måste beaktas vid energieffektiviseringar. Detta examensarbete syftar till att undersöka påverkan på primärenergianvändning och CO2-utsläpp genom optimering av livscykelkostnaderna (LCC) för historiska byggnader. Som fallstudie används 920 historiska byggnader i Visbys innerstad, indelade i tolv olika typbyggnader (6 träbyggnader, 1w-6w, och 6 stenbyggnader, 1s-6s). Tre fall undersöks: referensfall utan implementerade energieffektiviseringsåtgärder (fall 1), lägsta möjliga LCC (fall 2) och en minskning av energianvändningen med 50 % (fall 3). Inom examensarbetets kommer även de mest lönsamma energieffektiviseringsåtgärderna tas fram. Examensarbetet kommer också att visa hur lönsamheten för energirenovering varierar mellan de olika typbyggnaderna. Vid utförandet av examensarbetet tillämpas en tvärvetenskaplig metod som beaktar både kulturhistoriska värden och energibesparing. Tyngdpunkten ligger dock på användningen av programmet Optimal Energy Retrofit Advisory-Mixed Integer Linear Programming (OPERA-MILP), som är en del av den tvärvetenskapliga metoden. Med användningen av OPERA-MILP erhålls den kostnadsoptimala energieffektiviseringsstrategin för en byggnad. Programmet beaktar alla energirelaterade investeringskostnader, samt investering- och driftkostnader för värmetillförselsystem, under en bestämd tidsperiod. Resultaten visar unika energieffektiviseringspaket för de olika typbyggnaderna med en potential att sänka totala LCC för byggnadsbeståndet med 4-11 % och samtidigt minska energianvändningen med mer än 50 %. Examensarbetet visar också en möjlig minskning i primärenergianvändning med 24-57 %. CO2-utsläppen varierar mycket beroende på vilka antaganden görs relaterat till elektricitetsproduktion och användning av biomassa; resultaten visar ökningar upp till 224 % i CO2-utsläpp men också minskningar ned till 85 %. Samtliga typbyggnader är ekonomiskt lönsamma att energirenovera med LCC-besparingar på 1,4-11,8 SEK med en livscykel satt till 50 år för varje årligen sparad kWh, förutom i fall 3 då kostnader uppstår för varje årligen sparad kWh med 10,0-17,2 SEK, för ett antal av typbyggnaderna. / Potential and Policies for Energy Efficiency in Swedish Buildings Built Before 1945 (Stage II) - Energy Systems Analysis
430

Heat demand profiles of buildings' energy conservation measures and their impact on renewable and resource efficient district heating systems

Lundström, Lukas January 2016 (has links)
Increased energy performance of the building stock of European Union is seen as an important measure towards mitigating climate change, increasing resource utilisation efficiency and energy supply security. Whether to improve the supply-side, the demand-side or both is an open issue. This conflict is even more apparent in countries such as Sweden with a high penetration of district heating (DH). Many Swedish DH systems have high share of secondary energy resources such as forest industry residuals, waste material incineration and waste heat; and resource efficient cogeneration of electricity in combined heat and power (CHP) plants. When implementing an energy conservation measure (ECM) in a DH connected building stock, it will affect the operation of the whole DH system. If there are CHP plants and the cogeneration of electricity decreases due to an ECM, and this electricity is valued higher than the fuel savings, the consequences of the ECM would be negative.  These complex relationships are investigated by conducting a case study on the Eskilstuna DH system, a renewable energy supply system with relatively high share of cogenerated electricity. Heat demand profiles of ECMs are determined by building energy simulation, using recently deep energy retrofitted multifamily buildings of the “Million Programme”-era in Eskilstuna as model basis. How implementing ECMs impact on the DH system’s heat and electricity production under different electricity revenue scenarios has been computed and evaluated in terms of resource efficiency and CO2 emissions.  The results show that different ECMs in the buildings impact differently on the DH system. Measures such as improved insulation level of the building’s envelope, that decrease the heat demand’s dependence to outdoor temperature, increase the amount of cogenerated electricity. While measures such as thermal solar panels, which save heat during summer, affects the absolute amount of cogenerated electricity negatively. Revenues from cogenerated electricity influence the amount of cost-effectively produced electricity much more than the impact from ECMs. Environmental benefits of the ECMs, measured in CO2 emissions and primary energy consumption, are quite small in DH systems that have high share of forest residual fuels and electricity cogeneration. The consequences can even be negative if ECMs lead to increased need of imported electricity that is produced resource inefficiently or/and by fossil fuels. However, all studied ECMs increase the relative amount of cogenerated electricity, the ratio between amount of cogenerated electricity and the heat load. This implied that all ECMs increase the overall efficiency of the Eskilstuna DH system.

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