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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.
1

Three Essays Examining Household Energy Demand and Behavior

Murray, Anthony G. 23 July 2012 (has links)
This dissertation consists of three essays examining household energy decisions and behavior. The first essay examines the adoption of energy efficient Energy Star home appliances by U.S. households. Program effectiveness requires that consumers be aware of the labeling scheme and also change their purchase decisions based on label information. The first essay examines the factors associated with consumer awareness of the Energy Star label of recently purchased major appliances and the factors associated with the choice of Energy Star labeled appliances. The findings suggest that eliminating identified gaps in Energy Star appliance adoption would result in house electricity cost savings of \$164 million per year and associated carbon emission reductions of about 1.1 million metric tons per year. The second essay evaluates household energy security and the effectiveness of the Low-Income Home Energy Assistance Program (LIHEAP), the single largest energy assistance program available to poor households within the United States. Energy security is conceptually akin to the well-known concept of food security. Rasch models and household responses to energy security questions in the 2005 Residential Energy Consumption Survey are used to generate an energy insecurity index that is consistent with those found in the food insecurity literature. Participating in LIHEAP is found to significantly reduce household energy insecurity score in the index. Further, simulations show that the elimination of the energy assistance safety net currently available to households increases the number of energy insecure households by over 16 percent. The third essay develops a five equation demand system to estimate household own-price, cross-price and income elasticities between electricity, natural gas, food at home, food away from home, and non-durable commodity groups. Household cross-price elasticities between energy and food commodities are of particular importance. Energy price shocks reduce food expenditures for low-income households, as indicated by negative cross-price elasticity estimates for food and energy commodities. Additionally, low-income households reduce energy expenditures more than other households, further indicating ``heat or eat'' behavior. Results from all three essays provide policy makers with helpful information to shape future federal energy programs. / Ph. D.
2

An Empirical Assessment of Energy Management Information System Success Using Structural Equation Modeling

Stripling, Gwendolyn D. 01 January 2017 (has links)
The Energy Industry utilizes Energy Management Information Systems (EMIS) smart meters to monitor utility consumers’ energy consumption, communicate energy consumption information to consumers, and to collect a plethora of energy consumption data about consumer usage. The EMIS energy consumption information is typically presented to utility consumers via a smart meter web portal. The hope is that EMIS web portal use will aid utility consumers in managing their energy consumption by helping them make effective decisions regarding their energy usage. However, little research exists that evaluates the effectiveness or success of an EMIS smart meter web portal from a utility consumer perspective. The research goal was to measure EMIS smart meter web portal success based on the DeLone and McLean Information Success Model. The objective of the study was to investigate the success constructs system quality, information quality, service quality, use, and user satisfaction, and determine their contribution to EMIS success, which was measured as net benefits. The research model used in this study employed Structural Equation Modeling (SEM) based on Partial Least Squares (PLS) to determine the validity and reliability of the measurement model and to evaluate the hypothetical relationships in the structural model. The significant validity and reliability measures obtained in this study indicate that the DeLone and McLean Information Success Model (2003) has the potential for use in future EMIS studies. The determinants responsible for explaining the variance in net benefits were EMIS use and user satisfaction. Based on the research findings, several implications and future research are stated and proposed.
3

Avaliação do comportamento energético e exergético de um sistema de refrigeração por compressão de vapor. / Evaluation of the energy and exergetic behavior of a steam compression refrigeration system

ALBUQUERQUE, Carlos Eduardo da Silva. 25 July 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-07-25T23:39:27Z No. of bitstreams: 1 CARLOS EDUARDO DA SILVA ALBUQUERQUE – DISSERTAÇÃO (PPGEM) 2017.pdf: 4080439 bytes, checksum: 940fff54d861725d16972dec4bb0ee8c (MD5) / Made available in DSpace on 2018-07-25T23:39:27Z (GMT). No. of bitstreams: 1 CARLOS EDUARDO DA SILVA ALBUQUERQUE – DISSERTAÇÃO (PPGEM) 2017.pdf: 4080439 bytes, checksum: 940fff54d861725d16972dec4bb0ee8c (MD5) Previous issue date: 2017-03-17 / CNPq / Esta pesquisa apresenta uma análise energética e exergética de uma unidade de refrigeração de água gelada de grande porte, chamada chiller. O refrigerador em estudo realiza o ciclo termodinâmico de refrigeração com auxílio de um compressor mecânico, usualmente acionado por um motor elétrico, de forma a aumentar a pressão em determinada fase do ciclo termodinâmico do sistema, o que gera um alto consumo de energia elétrica. Com avanço da tecnologia, a cada dia surgem novos tipos de compressores que possuem um menor consumo de energia e melhoram o desempenho da unidade como um todo. O objetivo deste trabalho é avaliar os comportamentos energético e exergético, baseados respectivamente na primeira lei e na segunda lei da termodinâmica, de um chiller que fornece água gelada e trabalha com um compressor tipo parafuso. Este estudo foi realizado baseando-se no comportamento real de um chiller de compressão de vapor, instalado em um shopping da região de João Pessoa-PB. Através de simulação numérica, foi possível avaliar o comportamento do equipamento com a mudança de alguns dos parâmetros normais de trabalho, como pressões de condensação e evaporação, temperatura s de condensação e evaporação e fluido refrigerante. Neste estudo, são apresentados dados do desempenho do equipamento em função das pressões do evaporador e do compressor, da temperatura de evaporação, entre outros parâmetros. Os resultados das simulações, realizadas com auxilio do software EES, mostraram que o desempenho da unidade melhora ao diminuir a variação de pressão entre o condensador e o evaporador e que as eficiências energética e exergética sofrem um acréscimo com o aumento da temperatura de evaporação e uma redução com a elevação da temperatura de condensação. / This research presents energetic and exergetic analysis of a water refrigeration unit, called Chiller. The Chiller under study performs the thermodynamic cycle of the refrigeration with the assistance of a mechanical compressor, usually triggered by an electric motor, in order to increase the pressure in a certain stage on the thermodynamic cycle of the system, which generates high energy consumption. However, with the advance of the technology, every day emergs new types of compressors that have lowest energy consumption and improves the performance of the unit as a whole. The purpose of this work is to evaluate both e nergetic and exergetic behavior, of a chiller that provides cold water and works with a screw type compressor, based on the first and second laws of thermodynamics . This study was based on the actual behavior of a steam compression chiller from a mall in the city of João Pessoa-PB. Through numerical simulation, it was possible to evaluate the behavior of the equipment with the change of some of the normal parameters of work, as condensation and evaporation pressures, condensation and evaporation temperature and refrigerant fluid. In this study, the performance of the equipment data is presented as a function of the evaporator and compressor pressures, the evaporation temperature and other parameters. The results of the simulations, that were realized with support of software EES, showed that the unit performance was improved by decreasing the pressure variation between condenser and the evaporator and also has proved that the energetic and exergetic efficiences are increased by raising the evaporation temperature and a reduction happens by increasing the condensation temperature.
4

A Guideline for Establishing Local Energy-Efficiency Programs in Virginia

St.Jean, David Bryan 24 January 2011 (has links)
From a big picture perspective, investing in energy efficiency in the existing stock of residential buildings in the United States brings unquestioned economic, employment and environmental benefits. The aggregation of energy and dollar savings from millions of small improvements in efficiency adds up to enormous regional and national savings. By employing cost-effective investments in building efficiency, we could reduce the cumulative energy use of America's housing stock by twenty-eight percent, save Americans $41 billion annually, abate 360 megatons of CO-2 (Choi Granade, et.al., 2009), and meet fifty percent or more of the expected electric load growth by 2025 (EPA, 2008). In Virginia alone investing in the efficiency of our existing stock of buildings could save the commonwealth's residents $2.2 billion annually by 2025 (ACEEE, 2008). But from the perspective of the individual property owner the potential benefits of investing in energy efficiency, although just as real, are either less obvious or have impediments to their attainment. Understanding and overcoming these micro-impediments to energy investing is essential to realizing the macro-benefits of energy efficiency. Consequently, any successful local energy program must tailor its efforts to address the barriers to investing in efficiency at the level of the individual consumer. This thesis, through an analysis of existing and emerging residential energy programs, along with a review of the behavioral and economic literature on the subject, aims to point out the micro-impediments to achieving macro-reductions in energy use. Becoming familiar with these obstructions on the level of the individual consumer is the first necessary step in producing model guidelines for a successful whole house local energy efficiency program. Although the basic tenets of these guidelines could be used as the basis for any locally organized energy program in the U.S., they are specifically tailored in this thesis for the Commonwealth of Virginia. / Master of Urban and Regional Planning

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