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Gestão do consumo de energia elétrica: estudo de caso num instituto de pesquisa na cidade do Rio de JaneiroGonçalves, Orlando Augusto Vieira 25 November 2016 (has links)
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Previous issue date: 2016-11-25 / A crise energética tem ganhado bastante visibilidade na sociedade, nas empresas privadas e também nos órgãos públicos, suscitando ações necessárias para a redução do consumo de água e de energia elétrica. A pesquisa procura identificar a problemática do consumo de energia elétrica, com suas causas e efeitos, no contexto da crise hidroelétrica brasileira. Esta pesquisa tem por objetivo geral analisar e discutir as principais ações que devem ser tomadas para se obter a redução do consumo de energia elétrica em ambientes competitivos. Para tanto, tem como objetivos específicos: fazer uma revisão na literatura sobre a gestão do consumo de energia e identificar um conjunto de critérios que permitam avaliar a gestão de energia; estudar os modelos relatados na literatura com a indicação de ações que contemplem o uso racional e eficiente da energia elétrica; aplicar no estudo de caso os critérios encontrados na literatura e propor ações de melhoria e gestão eficaz do consumo elétrico ajustado a um Instituto de Pesquisa de uma Autarquia Federal no Rio de Janeiro. Uma revisão da literatura nas bases Scopus e SciELO foi realizada para dar suporte à construção desse modelo. Foi utilizado um questionário para definir e classificar o conjunto de critérios que contribuem para a redução do consumo no modelo utilizado. Um grupo de especialistas foi formado para validar os problemas encontrados e opinar sobre as soluções propostas. O método da pesquisa é indutivo de natureza exploratória e descritiva com abordagem quali-quantitativa. Os resultados da revisão da literatura apontaram para nove critérios relevantes e mostram que é possível alcançar uma redução no consumo de energia a partir do estudo desses critérios e de sua correlação com as variáveis coletadas no estudo de caso. Os resultados obtidos do questionário que foi aplicado junto aos especialistas no estudo de caso excluíram os três critérios menos relevantes, através da aplicação do Diagrama de Pareto. A pesquisa contribui para o desenvolvimento de uma metodologia para avaliação de ações visando o uso racional da energia elétrica. Contribui também para ações de planejamento sustentável que possam auxiliar as tomadas de decisão nos níveis operacional e gerencial num contexto de crise hidroelétrica. / The energy crisis has gained considerable visibility in society, in private companies and also in public agencies, provoking actions necessary to reduce water and electricity consumption. The research seeks to identify the problem of the consumption of electric energy, with its causes and effects, in the context of the Brazilian hydroelectric crisis. This research has as general objective to analyze and discuss the main actions that must be taken to obtain the reduction of the consumption of electric energy in competitive environments. To do so, it has specific objectives: to review the literature on the management of energy consumption and to identify a set of criteria for assessing energy management; To study the models reported in the literature with the indication of actions that contemplate the rational and efficient use of electric energy; To apply in the case study the criteria found in the literature and to propose actions of improvement and effective management of the adjusted electric consumption to a Research Institute of a Federal Autarchy in Rio de Janeiro. A review of the literature on Scopus and SciELO bases was carried out to support the construction of this model. A questionnaire was used to define and classify the set of criteria that contribute to the reduction of consumption in the model used. A group of experts was formed to validate the problems encountered and to give an opinion on the proposed solutions. The research method is inductive of an exploratory and descriptive nature with a qualitative-quantitative approach. The results of the literature review pointed to nine relevant criteria and show that it is possible to achieve a reduction in energy consumption based on the study of these criteria and their correlation with the variables collected in the case study. The results obtained from the questionnaire that was applied to the experts in the case study excluded the three less relevant criteria through the application of the Pareto Diagram. The research contributes to the development of a methodology for the evaluation of actions aimed at the rational use of electric energy. It also contributes to sustainable planning actions that can aid decision making at the operational and managerial levels in a context of hydroelectric crisis.
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Development of robust building energy demand-side control strategy under uncertaintyKim, Sean Hay 25 May 2011 (has links)
The potential of carbon emission regulations applied to an individual building will encourage building owners to purchase utility-provided green power or to employ onsite renewable energy generation. As both cases are based on intermittent renewable energy sources, demand side control is a fundamental precondition for maximizing the effectiveness of using renewable energy sources. Such control leads to a reduction in peak demand and/or in energy demand variability, therefore, such reduction in the demand profile eventually enhances the efficiency of an erratic supply of renewable energy.
The combined operation of active thermal energy storage and passive building thermal mass has shown substantial improvement in demand-side control performance when compared to current state-of-the-art demand-side control measures. Specifically, "model-based" optimal control for this operation has the potential to significantly increase performance and bring economic advantages. However, due to the uncertainty in certain operating conditions in the field its control effectiveness could be diminished and/or seriously damaged, which results in poor performance.
This dissertation pursues improvements of current demand-side controls under uncertainty by proposing a robust supervisory demand-side control strategy that is designed to be immune from uncertainty and perform consistently under uncertain conditions.
Uniqueness and superiority of the proposed robust demand-side controls are found as below:
a. It is developed based on fundamental studies about uncertainty and a systematic approach to uncertainty analysis.
b. It reduces variability of performance under varied conditions, and thus avoids the worst case scenario.
c. It is reactive in cases of critical "discrepancies" observed caused by the unpredictable uncertainty that typically scenario uncertainty imposes, and thus it increases control efficiency. This is obtainable by means of i) multi-source composition of weather forecasts including both historical archive and online sources and ii) adaptive Multiple model-based controls (MMC) to mitigate detrimental impacts of varying scenario uncertainties.
The proposed robust demand-side control strategy verifies its outstanding demand-side control performance in varied and non-indigenous conditions compared to the existing control strategies including deterministic optimal controls. This result reemphasizes importance of the demand-side control for a building in the global carbon economy. It also demonstrates a capability of risk management of the proposed robust demand-side controls in highly uncertain situations, which eventually attains the maximum benefit in both theoretical and practical perspectives.
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Adaptive neuro-fuzzy inference system (ANFIS)-based modelling of residential lighting load profile.Popoola, Olawale Muhammed. January 2015 (has links)
D. Tech. Electrical Engineering. / Aims of this study is to develop a residential customers' lighting profile ANFIS-based model. This model is expected to address lighting load usage estimation in relation to the dynamic occupancy presence in a residential dwelling, which will take into account the climatic condition (natural lighting) of such an environment (e.g. South Africa) and its income. The objectives are as follows: 1. Develop an ANFIS-based residential lighting load profile model for middle income, low income and high-income earners. 2. Error reduction in residential lighting demand profile model. Performance evaluation and validation of the model using correlation and trend analysis, regression model, South Africa power utility application lighting program, non-weighted approach and comparison with other research studies (methodology).3. Reduction in / or elimination of repeated models for occupant presence and assumptions that residences are occupied at certain periods. 4. Derive meaning from complexities (behavioural trends) associated with lighting usage and extract patterns in such circumstances.
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Eficiência energética em instalações residenciais considerando o novo ambiente de medição de consumo /León, María Fernanda Trujillo. January 2016 (has links)
Orientador: Oscar Armando Maldonado Astorga / Banca: Durval Luiz Silva Ricciulli / Banca: Pedro da Costa Junior / Resumo: O uso de novas tecnologias em equipamentos e dispositivos de consumo de energia elétrica, vem sendo uma ferramenta cada vez mais utilizada para aumentar a eficiência energética na geração, transporte e distribuição de energia. Mesmo com a crise econômica dos últimos anos, a demanda de energia elétrica tem apresentado um crescimento constante em alguns setores da distribuição, principalmente no consumo de instalações residenciais. Neste tipo de instalação, a introdução de tecnologia LED no sistema de iluminação vem crescendo de forma sistêmica resultando em economia para o consumidor que paga a energia consumida em kWh, sem preocupação com aspectos importantes que o consumidor industrial enfrenta como o baixo fator de potência e a distorção harmônica presente na instalação. Este quadro tende rapidamente a mudar com a instalação, nas residências, dos novos medidores digitais pelas distribuidoras, capazes de medir estes tipos de parâmetros. Atualmente, quando vista do lado do sistema de geração, a economia do consumidor em kWh pode não representar uma economia na geração de energia pois, por tratar-se de cargas não lineares, a relação entre o consumo na instalação e a energia necessária que precisa ser gerada nas Usinas para o seu atendimento, medido em kVA, pode não apresentar a mesma vantagem ou mesmo ser uma desvantagem para o sistema elétrico. Este trabalho tem por objetivo apresentar uma análise da utilização de tecnologia LED na iluminação em instalações residenciais, lev... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of new technologies in equipments and power consumption devices, it has been a tool to increase energy efficiency in the generation, transmission, and distribution of energy. Even with the economic crisis of recent years, electricity demand has shown a steady growth in some distribution sectors, especially in the consumer residential. In this type of plant facilities, the use of LED technology in lighting grows systemically resulting in the economy for the residential consumer who pays per kWh, without regard to important aspects that industrial consumers face as a low power factor and harmonic distortion present in the installation. This frame quickly tends to change with home electrical circuits, new digital meters by distributors, capable of measuring such parameters. Currently, from the viewpoint of the power generation system, the consumer economy in kWh may not represent savings in energy production. This assumption is valid because, as it is in non-linear loads the ratio between consumption in the installation and the required power must be provided in plants for your service, measured in kVA, can not present the same advantage or even be a disadvantage to the electrical system. This study aims to present an analysis of the use of LED technology in lighting in residential systems, considering the non-linearity of this new technology and the subsequent introduction in the installation, the increase in electrical losses this may entail. For this purpose, an experimental setup was performed using some of the most common appliances in residential appliances. These devices operate in conjunction with the lighting system. Thus, the outcomes of the different analyses led to considerations for the consumer and the certification agency. The Brazilian utilities are deploying a new digital measurement scenario, and the service clients must observe ... (Complete abstract click electroni access below) / Mestre
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Alojamento de cachaços em instalações climatizadas : analise de desempenho reprodutivo e do uso de energia eletrica / Accommodation of boars in acclimatized facilities : analysis of reproductive performance and use of electric energy.Velloso, Nina Miglioranza 29 February 2008 (has links)
Orientador: Luiz Antonio Rossi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-11T08:27:55Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: A importância da suinocultura brasileira no contexto socioeconômico do país é cada vez mais evidente. Por ser uma atividade que gera milhares de empregos anualmente, além de incrementar o produto interno bruto da nação por meio das expressivas exportações da carne suína, cada vez mais atenção é despendida com os requerimentos dos animais. Apesar disso, pouco tem sido pesquisado sobre as exigências de uma categoria em especial, a dos machos reprodutores do plantel, que são extremamente susceptíveis a condições climáticas adversas. Deste modo, torna-se importante a realização de estudos acerca dos requisitos necessários para mantê-los em conforto térmico, visto que são grandes as perdas na produção devido aos dias muito quentes e às grandes amplitudes térmicas. Uma alternativa para minimizar estas perdas é o uso de sistemas de climatização. Este trabalho teve por objetivo avaliar dois grupos de cachaços, grupos A e B, alojados, respectivamente, em instalações climatizadas por meio de sistema automatizado de ventilação artificial e nebulização, e em instalações climatizadas apenas por ventilação artificial e seguindo o manejo de acionamento dos ventiladores já praticado na propriedade. Foram considerados aspectos de desempenho reprodutivo e conforto térmico dos animais e do uso de energia elétrica pelos equipamentos de climatização. O experimento foi conduzido em uma granja comercial localizada na cidade de Capivari/São Paulo, com animais de uma mesma linhagem genética. O parâmetro utilizado na comparação do desempenho reprodutivo dos animais de ambos os grupos foi a análise das características do sêmen, que se relacionam diretamente com a taxa de prenhez das fêmeas. As edificações de alojamento dos animais também foram comparadas, avaliando-se variáveis climáticas, custos operacionais, gastos com equipamentos de climatização e automação, além da utilização da energia elétrica por parte dos mesmos. Os principais resultados obtidos demonstraram que o sistema de climatização automatizado manteve os animais em uma condição ambiental mais segura, porém não houve melhora nos índices de qualidade seminal dos animais deste grupo. Os valores médios de volume seminal e concentração espermática foram superiores nos animais do grupo B. Os impactos no custo mensal da conta de energia elétrica do posto transformador que fornece energia elétrica para a instalação dos cachaços foram de 2,26% e de 4,82%, para os dois meses completos avaliados / Abstract: Swine grow activities in Brazil is exhibiting an increasing importance to the national social economy. The particular attention devoted to the animal physical requirements is strongly supported by the direct and indirect job opportunities generated as well as by the significant swine meet exportation which push the national internal gross product to high levels. In spite of that, little research efforts has been directed to a special animal group identified as the breeding stock reproducing males, which are very susceptible to temperature changes. That information gives support to a deep study on animal thermal comfort, which is strongly associated to production losses and to the thermal amplitude variations. The application of environmental controlling systems aims to minimize these above referred losses. This research work aimed to evaluate two groups of males, named group A and group B, kept under artificial automatic ventilation and nebulization, as well as only under artificial ventilation following the traditional fan operation, respectively. Factors as reproducing performance, animal thermal comfort, as well as electrical energy use by the environment controlling system have been considered. Experimental trials were carried in a swine growing facility located at Capivari, SP, Brazil by employing animals belonging to a same commercial genetic group. Semen characteristics were employed as a factor of comparison, which are associated to the female pregnancy rate. The shelter¿s building of those animals were also compared, by assessing up climatic variables, operating costs, spending on air conditioning equipment and automation, and the use of electric energy by them. The main results showed that the automated system of air conditioning kept the animals in a safer environmental condition, however there was no improvement in seminal quality scores for the animals of this group. The mean values of seminal volume and sperm concentration were higher in the animals of group B. The impacts on the cost of monthly account of electric energy of the post processor, which provides electricity for the installation of males, were 2.26% and 4.82% for the two whole months assessed. / Mestrado / Construções Rurais e Ambiencia / Mestre em Engenharia Agrícola
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Análise de curvas funcionais agregadas com efeitos aleatórios / Analysis of aggregated functional curves with random effectLenzi, Amanda, 1988- 22 August 2018 (has links)
Orientador: Nancy Lopes Garcia / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-22T12:21:05Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: Neste trabalho tratamos de um problema de dados funcionais agregados, isto é, combinações lineares de curvas aleatórias que não podem ser observadas individualmente. A análise de curvas de carga de transformadores elétricos em linha de distribuição é uma situação onde tais dados são encontrados. O conjunto de dados consiste de diversas curvas agregadas; assumimos que cada curva individual é a realização de um processo Gaussiano com curva média que é modelada através da expansão em bases B-splines. Além disso, assumimos que os coeficientes também são desconhecidos e temos somente uma estimativa de tais números. Nosso objetivo é utilizar os valores aproximados desses coeficientes, além das curvas agregadas, para estimar o valor real dos coeficientes, a curva típica de cada subpopulação e parâmetros de variância. Para este fim, diferentemente de trabalhos anteriores sobre o tema, propomos a utilização de um modelo de efeitos aleatórios / Abstract: In this paper, we deal with a problem of aggregated functional data, i.e. linear combinations of random curves, which cannot be seen individually. The analysis of load curves of electrical transformers in the distribution line is a situation where those data are found. The data set consists of several aggregated curves; we assume that each individual curve is the realization of a Gaussian process with the mean curve modeled through the expansion in B-splines basis. Furthermore, we assume that the coefficients are also unknown and we have only an estimate of such numbers. Our goal is to use the approximate coefficients and the aggregated curve data to estimate the true coefficients, the typical curve of each subpopulation and variance parameters. For this purpose, unlike previous works on the subject, we propose using a random effects model / Mestrado / Estatistica / Mestra em Estatística
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Critical path method as a project modelling technique in coal refurbishment projects29 June 2015 (has links)
M.Ing. (Engineering Management) / South African power demand has been increasing over the past years due to increase in energy consumption from industrial, commercial and residential sectors. In order to meet the growing power demand Eskom Holdings Limited SOC (Eskom) has implemented a number of initiatives such as the energy efficiency programme, power generating capacity increase and refurbishment of the operational coal fired power stations. Energy efficiency initiatives have been designed to encourage residential, commercial and industrial customers to use energy efficient technologies which consume less energy compare to conventional technologies. Power generating capacity increase programme includes construction of new base and peaking generating power plants (such as Medupi, Kusile and Ingula) and return to service of the old generating plants (such as Camden, Komati and Grootvlei). The refurbishment programme or coal refurbishment involves upgrading of operational coal fired power stations with the objective of extending their life expectancy, improve performance and to ensure compliance to latest safety standards...
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"Demanda de energia elétrica e desenvolvimento socioeconômico: O caso das comunidades rurais eletrificadas com sistemas fotovoltaicos" / Electric Energy Consumption and Development Socioeconomic: the case of the electrified rural communities with photovoltaics systems.Trigoso, Federico Bernardino Morante 08 October 2004 (has links)
Este documento mostra uma interpretação do comportamento do consumo de energia elétrica baseada nos dados numéricos que foram coletados com o uso de contadores de Ah em 38 instalações fotovoltaicas domiciliares. A pesquisa envolveu igual número de famílias de 10 comunidades rurais com diferentes características sócioculturais localizadas nos Estados de São Paulo, Pernambuco e Amazonas, no Brasil, e adicionalmente na região Puno, no Peru. Também se discute diversas questões acerca do consumo de energia elétrica em sistemas fotovoltaicos domiciliares e sua relação com o desenvolvimento socioeconômico. O objetivo principal é propor um procedimento para dimensionar esses sistemas que inclua os múltiplos fatores que foram identificados e que exercem forte influência no comportamento do consumo. Estes foram denominados fatores técnicos, gerenciais, psicológicos, geográficos, demográficos, socioculturais e econômicos. O procedimento proposto leva em conta a constatação resultante da análise estatística dos dados por meio da qual a função de distribuição Gama é a que melhor caracteriza o comportamento desse consumo. Em sua essência, esta função indica que muitas pessoas consomem pouco e poucas pessoas consomem muito". / This document shows an interpretation of the behavior of the electric energy consumption based on the numerical data collected with the use of Ah meter in 38 solar home systems. The research involved an equal number of families of 10 rural communities with different sociocultural characteristics located in the Brazilian States of São Paulo, Pernambuco and Amazonas, and additionally in the Puno region, in Peru. It also raises several points concerning the electric energy consumption in SHS´s and its relationship with the socioeconomic development. The main objective is to suggest a procedure for the sizing of SHS´s that includes the several factors that were identified and that exert strong influence in the behavior of the consumption. These were called technical, administrative, psychological, geographical, demographical, sociocultural and economic factors. This procedure takes into account the evidence resultant of the statistic analysis of the data by means of which the Gamma distribution function is the one which better characterizes the behavior of this consumption. Essentially, this function indicates that many people consume little and few people consume much".
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Short-term multiple forecasting of electric energy loads with weather profiles for sustainable demand planning in smart grids for smart homesAlani, Adeshina Yahaha 01 1900 (has links)
Energy consumption in the form of fuel or electricity is ubiquitous globally. Among energy types, electricity is crucial to human life in terms of cooking, warming and cooling of shelters, powering of electronic devices as well as commercial and industrial operations. Therefore, effective prediction of future electricity consumption cannot be underestimated. Notably, repeated imbalance is noticed between the demand and supply of electricity, and this is affected by different weather profiles such as temperature, wind speed, dew point, humidity and pressure of the electricity consumption locations. Effective planning is therefore needed to aid electricity distribution among consumers. Such effective planning is activated by the need to predict future electricity consumption within a short period and the effect of weather variables on the predictions. Although state-of-the-art techniques have been used for such predictions, they still require improvement for the purpose of reducing significant predictive errors when used for short-term load forecasting. This research develops and deploys a near-zero cooperative probabilistic scenario analysis and decision tree (PSA-DT) model to address the lacuna of significant predictive error faced by the state-of-the-art models and to analyse the effect of each weather profile on the cooperative model. The PSA-DT is a machine learning model based on a probabilistic technique in view of the uncertain nature of electricity consumption, complemented by a DT to reinforce the collaboration of the two techniques. Based on detailed experimental analytics on residential, commercial and industrial data loads, the PSA-DT model with weather profiles outperforms the state-of-the-art models in terms of accuracy to a minimal error rate. This implies that its deployment for electricity demand planning will be of great benefit to various smart-grid operators and homes. / School of Computing / M. Sc. (Computer Science)
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Harnessing resilience: biased voltage overscaling for probabilistic signal processingGeorge, Jason 26 October 2011 (has links)
A central component of modern computing is the idea that computation requires
determinism. Contrary to this belief, the primary contribution of this work shows that
useful computation can be accomplished in an error-prone fashion. Focusing on low-power
computing and the increasing push toward energy conservation, the work seeks to sacrifice
accuracy in exchange for energy savings.
Probabilistic computing forms the basis for this error-prone computation by diverging from the requirement of determinism and allowing for randomness within computing.
Implemented as probabilistic CMOS (PCMOS), the approach realizes enormous energy sav-
ings in applications that require probability at an algorithmic level. Extending probabilistic
computing to applications that are inherently deterministic, the biased voltage overscaling
(BIVOS) technique presented here constrains the randomness introduced through PCMOS.
Doing so, BIVOS is able to limit the magnitude of any resulting deviations and realizes
energy savings with minimal impact to application quality.
Implemented for a ripple-carry adder, array multiplier, and finite-impulse-response (FIR)
filter; a BIVOS solution substantially reduces energy consumption and does so with im-
proved error rates compared to an energy equivalent reduced-precision solution. When
applied to H.264 video decoding, a BIVOS solution is able to achieve a 33.9% reduction in
energy consumption while maintaining a peak-signal-to-noise ratio of 35.0dB (compared to
14.3dB for a comparable reduced-precision solution).
While the work presented here focuses on a specific technology, the technique realized
through BIVOS has far broader implications. It is the departure from the conventional
mindset that useful computation requires determinism that represents the primary innovation of this work. With applicability to emerging and yet to be discovered technologies,
BIVOS has the potential to contribute to computing in a variety of fashions.
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