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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.
11

Sustentabilidade energética: um estudo da viabilidade econômica e financeira do uso de energia solar na avicultura / Energy sustainability: a study of the economic and financial viability of the use of solar energy in poultry

Silva, Alexandre Adilio Luiz da 18 December 2017 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-02-20T14:14:53Z No. of bitstreams: 2 ALEXANDRE ADILIO LUIZ DA SILVA.pdf: 1526392 bytes, checksum: ab994f0b054031d6002cf4582b905494 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-20T14:14:53Z (GMT). No. of bitstreams: 2 ALEXANDRE ADILIO LUIZ DA SILVA.pdf: 1526392 bytes, checksum: ab994f0b054031d6002cf4582b905494 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-12-18 / The promotion of energy sustainability and the use of renewable energy sources have become a challenge to the planet. Brazil has a great advantage in having the best conditions in all its territory for the generation of clean energies, thus it seeks to improve the development of its energy matrix, which demands a restructuring, mainly in the creation of new foment policies, incentives and laws to regulate these inexhaustible sources of energy. The creation of these mechanisms should motivate the competitiveness and creation of new companies in the production of these technologies, especially solar energy, which currently involves high costs for the acquisition of equipment and facilities. In this context, the objective of this work was to perform an analysis on energy sustainability through an economic and financial feasibility study of the use of photovoltaic solar panels in poultry, and a chicken farm located in the city of Toledo-PR. In order to respond to the research problem and to meet the proposed objectives, three steps were developed in the study, the first of which refers to a survey on the environmental perception of poultry farmers in Toledo-PR, through the application of questionnaires, 66 poultry farmers in Toledo -PR, including the farmer of the studied chicken farm. After analyzing the data, it was identified that there is a potential for these poultry farmers to become ecological consumers, and that electricity is the highest cost in the poultry production process. In the second study, a proposal was presented to improve the cost management of the broiler chicken farm using the methodology developed by Embrapa Poultry and Swine by means of a control sheet. After collecting the data and all the costs of the aviaries, it was verified that the electric energy is the greater cost among the others existing in the aviaries, and that the gross revenue of the producer is negative. The third study analyzed the economic and financial viability for a farm energy sustainability project through solar energy. For this step, the Net Present Value (NPV), Internal Rate of Return (IRR) and Payback Time were used. To conclude, the Sensitivity Analysis was carried out with three possible scenarios for the investment project. The results show that for all scenarios the project is still not feasible, and as possible causes are the high cost of acquisition of solar technology and the lack of alignment with the deadlines for financing, which make the annual parcels unsustainable the poultry activity. Although the acquisition costs of this technology are decreasing and Brazil is encouraging the use of renewable energies, there is still much to improve, starting with the public policies to encourage the use of these clean sources, especially solar photovoltaic energy in rural properties such as poultry farming that contributes so much to the Brazilian economy. / A promoção da sustentabilidade energética e a utilização das fontes alternativas de energias renováveis se tornaram um desafio ao planeta. O Brasil detém uma grande vantagem por ter as melhores condições em todo o seu território para a geração de energias limpas, e assim, busca melhorar o desenvolvimento de sua matriz energética, o que demanda uma reestruturação, principalmente na criação de novas políticas de fomento, incentivos e leis para regulamentar essas fontes inesgotáveis de energia. A criação destes mecanismos deve motivar a competitividade e a criação de novas empresas na produção dessas tecnologias, principalmente a energia solar, que envolve atualmente altos custos para aquisição e implantação dos equipamentos e instalações. Neste contexto, o objetivo deste trabalho foi realizar uma análise sobre a sustentabilidade energética através de um estudo de viabilidade econômica e financeira do uso de painéis solares fotovoltaicos na avicultura. Para tal foi estudada uma granja de frango de corte localizada no município de Toledo-Pr. Para responder ao problema de pesquisa e atender aos objetivos propostos desenvolveu-se uma metodologia dividida em três etapas no estudo. A primeira etapa se refere a uma pesquisa com dados primários sobre a percepção ambiental dos avicultores de Toledo-PR, em que aplicou-se questionários para 66 avicultores do município, incluindo o produtor da granja de frango de corte estudada. Após a análise dos dados, como resultado, identificou-se que existe um potencial destes avicultores se tornarem consumidores ecológicos, e que a energia elétrica é um dos maiores custos existentes no processo de produção das aves. No segundo estudo foi apresentado uma proposta de melhoria na gestão de custos da granja de frango de corte, utilizando a metodologia desenvolvida pela Embrapa Aves e Suínos, por meio de uma planilha de controle. Após coleta dos dados e todos os custos dos aviários, comprovou-se que a energia elétrica é um dos custos com maior peso dentre os demais existentes nos aviários, e que o produtor rural está obtendo prejuízo com a receita bruta negativa, quando analisada sob a visão financeira, por outro lado, sob uma visão econômica, sem considerar alguns custos, o produtor rural tem uma receita bruta positiva. O terceiro estudo analisou a viabilidade econômica e financeira para um projeto de sustentabilidade energética da granja, através da energia solar. Para essa etapa foram utilizados os métodos de Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), Taxa Interna de Retorno Modificada (MTIR) e o Tempo de Retorno (Payback). Para concluir foi realizada a Análise de Sensibilidade com três cenários possíveis para o projeto de investimento, analisando a questão financeira e uma análise de viabilidade com a visão econômica. Os resultados mostram que para todos os cenários financeiros o projeto ainda é inviável, e como possíveis causas está o alto custo de aquisição da tecnologia solar e a falta de alinhamento com os prazos para financiamento, que tornam as parcelas anuais insustentáveis a atividade avícola, uma vez que o produtor tem sua receita bruta negativa. Mas, para um estudo sob a visão econômica e considerando as questões ambientais, sociais e legais, o projeto se torna viável. Embora os custos de aquisição desta tecnologia estejam declinando e o Brasil esteja incentivando o uso de energias renováveis, ainda há muito o que precisa ser feito, começando pelas políticas públicas de incentivo ao uso dessas fontes limpas, em especial a energia solar fotovoltaica em propriedades rurais, como é o caso da avicultura que tanto contribui na economia brasileira.
12

Análise de viabilidade sócio-ambiental e econômica de alternativas de produção energética de subprodutos do sistema sucroenergético para usinas da região de Ribeirão Preto - SP / Socio-environmental and economic feasibility analysis of alternatives for energy production from sugarcane byproducts system for plants in the region of Ribeirão Preto - SP

Alexei José Zaratini 11 October 2013 (has links)
O tema sustentabilidade tem sido mais valorizado à medida que a humanidade começa a perceber as consequências em desprezar as leis de equilíbrio natural dos recursos disponíveis. A partir daí, reorganizar as formas de produção em vistas do melhor aproveitamento de subprodutos, bem como focalizar os esforços e recursos em fontes renováveis de energia, são pontos cada vez mais importantes. A matriz elétrica brasileira é predominantemente de origem hidrelétrica; porém, outras fontes de energia, inclusive geradas a partir de resíduos, também têm recebido maior atenção no Brasil. Nesse contexto, o objetivo geral desta pesquisa é avaliar a viabilidade sócio-ambiental e econômica de alternativas de produção energética a partir de subprodutos do sistema sucroenergético. A presente pesquisa é do tipo qualiquantitativa, aplicada, envolvendo a caracterização e comparação das diversas alternativas, a partir de variáveis de custo, produção, logística, emissões, recolhimento de impostos, eficiência energética, dentre outras. Para a coleta de dados primários foram realizadas entrevistas com gestores e técnicos de usinas do setor sucroenergético, pesquisadores da área, bem como responsáveis por políticas públicas no tema de estudo. Para a coleta de dados quantitativos, foram utilizados formulários, a fim de levantar dados referentes a volume de resíduos produzido, produtividade energética das alternativas, custos de implantação e de outros processos e variáveis relacionados. As análises quantitativas dos dados foram realizadas a partir da aplicação de um modelo de Simulação de Monte Carlo e análises de sensibilidade, dentro do contexto da metodologia RBMCA (Risk-Based Multi Criteria Assessment). Para as análises econômicas de viabilidade do investimento, foram utilizadas técnicas de matemática financeira, como Coeficiente Benefício/Custo (B/C) e Valor Presente Líquido (VPL) das alternativas. Como resultado, a pesquisa permitiu trazer à realidade do setor sucroenergético brasileiro uma metodologia de análise de viabilidade que leva em consideração o risco envolvido nas variáveis consideradas, a RBMCA, aplicada sobre projetos envolvendo o bagaço, a vinhaça e o palhiço. Permitiu ainda verificar o direcionamento das pesquisas realizadas sobre alternativas de aproveitamento dos subprodutos sucroenergéticos e a disponibilidade de informações referentes a aspectos socioambientais dos projetos envolvidos nas análises. Ao final da aplicação da metodologia, foi possível verificar que há uma diferença de viabilidade dos projetos que torna necessário o aprofundamento das pesquisas dedicadas a levantar aspectos socioambientais e de viabilidade técnica de mais projetos que possam ser implantados. / Sustainability has been more valued as humanity begins to realize the consequences for disregarding laws of balance of natural resources. Then, rearranging production ways and processes in view of better utilization of by-products, as well as focusing efforts and resources on renewable energy sources are becoming increasingly important points. The Brazilian energy matrix is predominantly hydroelectric but other energy sources including the ones generated from wastes also have receives increasing attention in Brazil. In this context the objective of this research is to evaluate socioeconomic and environmentalfeasibility of alternativesfor energy production from sugarcane by-products. This type of research is qualitative and quantitative, applied, involving the characterization and comparison of various alternatives, as cost variables, production, logistics, emissions, tax payment, energy efficiency, among others. For primary data collection, interviews were conducted with managers and technicians of sugarcane industry, researchers and policy makers in the field of study. To collect quantitative data forms were used in order to collect data regarding the volume of waste produced, energy productivity of alternatives, implementation costs and other related processes and variables. Quantitative analyzes of data were performed by the application of a model of Monte Carlo simulation and sensitivity analyzes within the context of the methodology RBMCA (Risk-Based Multi Criteria Assessment). For economic feasibility analysis of investment were applied financial mathematic techniques, such as coefficient Benefit / Cost (B / C) and Net Present Value (NPV) of the alternatives. As a result, the research allowed bringing to Brazilian sugarcane industry reality a methodology of feasibility assessment that takes into account the risk involved in the variables considered, the RBMCA, applied to projects involving bagasse, vinasse and straw. Research also allowed to check the direction of researches dedicatedto analyses alternatives uses of sugar and ethanol byproducts and availability of information regarding the environmental aspects of the projects involved in the analyzes. At the end of methodology application, it was possible to verify that there is a difference in projects feasibility which makes necessary the research development dedicated to raising environmental aspects and technical feasibility of more projects that can be deployed.
13

Socio-Economic Sustainability of Rural Energy Access in India

Udayakumar, Suhasini January 2016 (has links)
Rural energy access has been a persistent issue in India causing the country to become one of the most energy poor nations of the world. Despite the launch of several heavily funded programs for the provision of electricity and modern fuels to rural areas, majority of the country‘s village households remain neglected and deficient in energy. Calls have been made for the reconstruction of policies, programs and institutional frameworks that engage in dispersion of energy to the rural poor. Such policies, programs and institutional frameworks vary across different states within India. These differences need to be understood in depth to formulate suitable mechanisms for energy access. In particular, social and economic aspects of energy access need to be studied to overcome barriers in providing energy to the rural poor. This study discerns how different states are performing in terms of providing sustainable energy access to rural people. It conducts an analysis of the socio-economic sustainability of energy access to the rural household in six states of the country (Andhra Pradesh, Himachal Pradesh, Maharashtra, Punjab, Rajasthan and West Bengal) over the course of two time periods(1996-2002, 2005-2011), with the aid of key performance indicators. Results indicate that all the states have improved their energy access conditions over the past few decades. However, the rates of growth are vastly different and some states still continue to remain highly inadequate in their performances. Punjab has consistently been the most successful state while West Bengal continues to be the most energy-poor state despite a reasonable growth in energy sustainability. The possible reasoning behind these disparities could be dissimilarity in economic development between the states, size and population density of the states, isolation of villages and ineffectiveness and inequity of subsidy schemes. These needs further exploration at individual state level. Transition to less-expensive and easily installable renewable technologies, communicating benefits of modern energy to rural population and channeling subsidies towards lower income groups can improve reach of modern energy towards the rural poor of India.
14

Enhancing nuclear energy sustainability using advanced nuclear reactors

Elshahat, Ayah Elsayed January 2015 (has links)
The safety performance of nuclear power reactors is a very important factor in evaluating nuclear energy sustainability. Improving the safety performance of nuclear reactors can enhance nuclear energy sustainability as it will improve the environmental indicator used to evaluate the overall sustainability of nuclear energy. Great interest is given now to advanced nuclear reactors especially those using passive safety components. Investigation of the improvement in nuclear safety using advanced reactors was done by comparing the safety performance of a conventional reactor which uses active safety systems, such as Pressurized Water Reactor (PWR), with an advanced reactor which uses passive safety systems, such as AP1000, during a design basis accident, such as Loss of Coolant Accident (LOCA), using the PCTran as a simulation code. To assess the safety performance of PWR and AP1000, the “Global Safety Index” GSI model was developed by introducing three indicators: probability of accident occurrence, performance of safety system in case of an accident occurrence, and the consequences of the accident. Only the second indicator was considered in this work. A more detailed model for studying the performance of passive safety systems in AP1000 was developed. That was done using SCDAPSIM/RELAP5 code as it is capable of modelling design basis accidents (DBAs) in advanced nuclear reactors.
15

Hydropower in Scotland : linking changing energy and environmental agendas with sustainability outcomes

Nelson, Edward January 2013 (has links)
As the UK energy sector moves to a greater contribution from low-carbon and renewable sources it faces significant challenges in delivering affordability, security of supply and sustainability. Although hydropower in Scotland emerged on a large scale in the mid-20th century against an influential, changing wider context of energy policy, environmental regulation and debate, it is now subject to an evolving renewables agenda. This further shapes the national and scheme level characteristics of hydropower and in turn outcomes for the water environment. Contingent upon these considerations, hydropower regulation must now deliver on EU obligations to protect and improve the ecological status of water bodies, whilst also supporting domestic efforts to meet high profile binding renewable energy targets. Yet, despite an acknowledged potential for energy policy to constrain the delivery of water policy objectives, there is little policy harmonisation between disciplines. As Scotland orientates itself as a leader in Europe on climate change, transitioning to increasing amounts of renewable generation across a handful of technologies, there is a gap in knowledge about how specific renewable policies and trends can influence hydropower sustainability outcomes and regulatory challenges. This thesis therefore contributes an innovative and timely critical examination of the effect a changing wider renewable energy and policy context has on hydropower sustainability in Scotland, at a scheme and national level. This research uses an interdisciplinary, temporal analysis to identify linkages and create dialogue between disciplines and scales, informing the pursuit of sustainable renewable energy through policy and regulation in a changing world. It finds firstly, that the changing national generation mix towards an increased contribution from renewable sources, including potentially intermittent technologies such as wind power, has contributed to an alteration in the operational characteristics and reservoir variability profile of Cruachan pumped-storage scheme, presenting positive outcomes for reservoir littoral habitats. Secondly, it finds that whilst not operating in isolation, renewable energy incentive policies, through their eligibility criteria, financial reward frameworks and timing, influence hydropower characteristics and sustainability challenges, providing trade-offs but also synergies for hydropower regulation. Finally, it finds that there is a degree of divergence in hydropower outcomes and challenges in Scotland and Norway, due to the characteristics and especially interaction of wider contextual elements such as topography, profile of precipitation input, national energy needs and the role of regional and municipal government. By highlighting these linkages, this thesis is of value to energy policy and environmental regulation in Scotland and across the EU, and is seen as a first step in addressing these uncertainties and supporting a more integrated and sustainable hydropower and renewables governance framework.
16

Sustentabilidade energética: uma análise do equilíbrio econômico, humano e natural. / Energy sustainability : an analysis of economic, human and natural balance.

Fujii, Ricardo Junqueira 19 March 2015 (has links)
O desenvolvimento sustentável e a própria sobrevivência da humanidade dependem da compatibilização da demanda por recursos energéticos com as limitações ambientais e necessidades humanas. Dessa maneira, torna-se fundamental compreender e mensurar a sustentabilidade energética. Para tanto, esse trabalho vale-se de princípios da economia ecológica e do planejamento integrado de recursos para identificar e analisar os fatores que afetam a sustentabilidade energética de um dado sistema. A partir desses fatores são definidos indicadores de sustentabilidade, os quais compõem uma metodologia concebida para avaliar o grau de sustentabilidade da produção de energia. Tal metodologia é testada em um estudo de caso da matriz elétrica paulista, a qual mostrou um nível próximo da sustentabilidade, mas com a necessidade de aprimoramentos. Por fim, são feitas reflexões sobre a robustez, a flexibilidade e as limitações da metodologia proposta, assim como recomendações para ajustes da composição da matriz estudada com o propósito de torná-la mais sustentável. / Sustainable development and the very survival of humanity depends on the compatibility of the demand for energy resources with environmental constraints and human needs. Thus, it is essential to understand and define metrics for energy sustainability. For that reason, this work draws on principles of ecological economics and integrated resource planning to identify and analyze the factors affecting energy sustainability of a given system. From these factors are defined sustainability indicators, which are the foundations for a methodology designed to assess the degree of sustainability of energy production. The methodology is tested on a case study of the electricity matrix of the State of Sao Paulo, which is close to a sustainable level even though requiring improvements in some aspects. Finally, reflections on the sturdiness, flexibility and limitations of the proposed methodology, as well as recommendations for adjustments in the composition of the case study matrix in order to make it more sustainable are made.
17

Sustentabilidade energética: uma análise do equilíbrio econômico, humano e natural. / Energy sustainability : an analysis of economic, human and natural balance.

Ricardo Junqueira Fujii 19 March 2015 (has links)
O desenvolvimento sustentável e a própria sobrevivência da humanidade dependem da compatibilização da demanda por recursos energéticos com as limitações ambientais e necessidades humanas. Dessa maneira, torna-se fundamental compreender e mensurar a sustentabilidade energética. Para tanto, esse trabalho vale-se de princípios da economia ecológica e do planejamento integrado de recursos para identificar e analisar os fatores que afetam a sustentabilidade energética de um dado sistema. A partir desses fatores são definidos indicadores de sustentabilidade, os quais compõem uma metodologia concebida para avaliar o grau de sustentabilidade da produção de energia. Tal metodologia é testada em um estudo de caso da matriz elétrica paulista, a qual mostrou um nível próximo da sustentabilidade, mas com a necessidade de aprimoramentos. Por fim, são feitas reflexões sobre a robustez, a flexibilidade e as limitações da metodologia proposta, assim como recomendações para ajustes da composição da matriz estudada com o propósito de torná-la mais sustentável. / Sustainable development and the very survival of humanity depends on the compatibility of the demand for energy resources with environmental constraints and human needs. Thus, it is essential to understand and define metrics for energy sustainability. For that reason, this work draws on principles of ecological economics and integrated resource planning to identify and analyze the factors affecting energy sustainability of a given system. From these factors are defined sustainability indicators, which are the foundations for a methodology designed to assess the degree of sustainability of energy production. The methodology is tested on a case study of the electricity matrix of the State of Sao Paulo, which is close to a sustainable level even though requiring improvements in some aspects. Finally, reflections on the sturdiness, flexibility and limitations of the proposed methodology, as well as recommendations for adjustments in the composition of the case study matrix in order to make it more sustainable are made.
18

Conception d’observateurs pour la commande d’un système pile à combustible embarqué en vue d’optimiser performances et durabilité / Observer design for control of an on-board fuel cell system to optimize performance and durability

Piffard, Maxime 01 December 2017 (has links)
Les piles à combustibles sont considérées comme une énergie d’avenir, notamment grâce à leur caractère non polluant à l’usage. Cependant, le déploiement de ces solutions à grande échelle est encore conditionné par l’amélioration de leurs performances et surtout de leur durabilité afin de garantir une industrialisation à faible coût. L’application de la pile à combustible au domaine des transports impose en plus un fonctionnement à puissance variable, ce qui complique l’amélioration des performances et de la durabilité. L’approche retenue pour ces travaux consiste en la conception d’une loi de gestion du système qui génère les conditions opératoires optimales à appliquer au stack (pressions, température, courant, stoechiométries) en fonction de la demande en puissance, de l’état de santé de la pile (perte de surface active) et du taux d’humidité actuel. L’optimalité est entendue au sens de l’augmentation du rendement système et de la diminution des dégradations du platine et de la membrane. Cette loi se base sur des modèles de dégradations et de performances d’un système pile à combustible. Cette loi de gestion requiert pour fonctionner les données de l’état de santé de la pile et du taux d’humidité. L’évaluation de l’état de santé de la pile fait déjà l’objet de nombreux travaux de diagnostic. En revanche, le taux d’humidité doit être estimé par un observateur d’état car les capteurs d’humidité ne sont pas fiables pour une application transport. Pour cela, un observateur d’état a été développé pour estimer les humidités relatives dans les canaux du stack et aussi le chargement en eau de la membrane, la quantité d’hydrogène à l’anode ainsi que la saturation d’azote à l’anode. Cette dernière donnée permet de proposer une stratégie de purge pour une architecture dead-end basée sur la saturation d’azote, qui limite les pertes en hydrogène et réduit les dégradations liées à cette architecture. / Fuel cells are considered as a promising source of energy for the future, thanks to their non-polluting aspect. However, the deployment of these solutions on a large scale is still conditioned by the improvement of their performance and especially of their durability in order to guarantee a low cost industrialization. The transport application also imposes a variable power demand, which complicates the improvement of performance and durability. The approach adopted for this work consists of the design of a system management law that generates the optimal operating conditions to be applied to the stack (pressures, temperature, current, stoichiometries) as a function of the power demand, the state of health (active surface loss) and current humidity. Optimality is understood in the sense of increasing system efficiency and decreasing the degradation of the membrane and the platinum dissolution. This law is based on degradation and performance models of a fuel cell system. This management law requires in real time the data of the state of health of the fuel cell and the humidity rate. The assessment of the state of health is already the subject of many diagnostic work. On the other hand, the humidity rate must be estimated by a state observer because the humidity sensors are not reliable for a transport application. Therefore, a state observer was developed to estimate the relative humidities in the stack channels and also the membrane water content, the hydrogen at the anode as well as the nitrogen saturation at the anode. This last data makes it possible to propose a purge strategy for a dead-end architecture, based on nitrogen saturation, which limits the losses in hydrogen and reduces the damage associated with this architecture.

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