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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.
151

Correlação entre compacidade, energia incorporada e emissões de CO2, em projetos de habitação de interesse social / Correlation betwenn design compactness and constructive systems applied in social housing with embodied energy and CO2 emissions

Postay, Renata 27 March 2015 (has links)
Submitted by Maicon Juliano Schmidt (maicons) on 2015-08-06T18:22:40Z No. of bitstreams: 1 Renata Postay.pdf: 3569727 bytes, checksum: 4d066a333e97647bdda37f1b5c173ac2 (MD5) / Made available in DSpace on 2015-08-06T18:22:40Z (GMT). No. of bitstreams: 1 Renata Postay.pdf: 3569727 bytes, checksum: 4d066a333e97647bdda37f1b5c173ac2 (MD5) Previous issue date: 2015-03-27 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Ministério das Cidades / UNISINOS - Universidade do Vale do Rio dos Sinos / A construção civil consome uma grande quantidade de matérias primas e energia. No consumo de energia especificamente, o segmento residencial é muito expressivo pois utiliza o equivalente aos setores comercial e público juntos, em todas as fontes de energia, envolvendo desde a energia para a produção de materiais e componentes, como a energia utilizada na fase de uso das edificações. No Brasil, o setor de habitação de interesse social (HIS) teve um impulso significativo com o Programa Minha Casa Minha Vida (PMCMV), que objetiva a redução do deficit habitacional brasileiro e a promoção do crescimento econômico. Práticas de ações voltadas à economia e otimização da construção, desde a fase de projeto até a execução, são muito oportunas, tendo em vista a atual crise energética que o país vem enfrentando e a escala do segmento de HIS. Neste contexto, o projeto tem papel crucial como indutor da racionalização da construção, pois, a escolha dos materiais e decisões quanto à arquitetura tem influência direta no consumo de materiais e impactos relacionados. O estudo busca investigar o efeito da compacidade do projeto (através do índice econômico de compacidade – IeC) em diferentes sistemas construtivos, utilizados em empreendimentos de habitação de interesse social (EHIS), na energia incorporada (EI) e nas emissões de CO2. A pesquisa analisou cinco projetos de edifícios do PMCMV, e para cada um considerou três sistemas construtivos (alvenaria estrutural com blocos cerâmicos, alvenaria estrutural com blocos de concreto e paredes de concreto). A pesquisa foi conduzida através de três etapas: (1) quantificação dos materiais dos projetos; (2) análise da energia incorporada e emissões de dióxido de carbono (CO2) dos materiais de construção através de dados publicados na literatura e em dados do software Cambridge Engineering Select; (3) verificação da correlação entre compacidade, energia incorporada e emissões de CO2. Quanto ao consumo de materiais, os resultados mostram diferença aproximada de 20% em massa (kg) entre os projetos com menor e maior índice econômico de compacidade, e diferença entre 16% a 20% na análise de EI e emissões de CO2, quando são analisados projetos de um mesmo sistema construtivo. / Civil construction consumes a large amount of raw materials and energy. In energy consumption specifically, the residential segment is very significant because it uses, in all energy sources, the equivalent of the commercial and public sectors together, ranging from the energy to materials and components production, such as the energy used in the use phase of buildings. In Brazil, the social housing sector had a significant growth with the program “Minha Casa Minha Vida (MCMV)” (my house, my life), which aims to reduce the Brazilian housing deficit and to promote economic growth. Actions aimed at saving and optimization of construction are very timely, from the design stage to execution, given the current energy crisis the country is facing, and the scale of social housing segment. In this context, the design plays a crucial role as an inducer of the rationalization of construction, therefore, the choice of materials and decisions on the architecture has a direct influence on materials consumption and related impacts. The study aims to investigate the relationship between design compactness (through economic index of compactness) and construction systems used in social housing developments (EHIS) with embodied energy and CO2 emissions. The research examined five designs of buildings of MCMV, considering construction systems (structural masonry with ceramic bricks, masonry with concrete blocks and concrete walls) for each design. The study was conducted through three steps: (1) quantification of the materials of the designs; (2) analysis of the embodied energy and carbon dioxide (CO2) emissions, from data published in the literature and in the CES Selector software; (3) verification of the relationship between compactness and construction systems, with consumption of EI and CO2 emissions. Regarding the consumption of materials, the results show an approximate 20% difference in weight (kg) between projects with lower and higher economic index of compactness, and the difference between 16% to 20% in EI analysis and CO2 emissions, considering the same construction system.
152

Essays on energy efficiency and fuel subsidy reforms

Tajudeen, Ibrahim January 2018 (has links)
This thesis uses innovative approaches to analyse energy policy interventions aimed at enhancing the environmental sustainability of energy use as well as its consequential welfare implications. First, we examine the relationship between energy efficiency improvement and CO2 emissions at the macro level. We use the Index Decomposition Analysis to derive energy efficiency by separating out the impact of shifts in economic activity on energy intensity. We then employ econometric models to relate energy efficiency and CO2 emissions accounting for non-economic factors such as consumers lifestyle and attitudes. The applications for 13 OPEC and 30 OECD countries show that at the country-group and individual country level, increase in energy intensity for OPEC is associated with both deteriorations in energy efficiency and shifts towards energy-intensive activities. The model results suggest that the reduction in energy efficiency in general go in tandem with substantial increases in CO2 emissions. The decline in energy intensity for OECD can be attributed mainly to improvements in energy efficiency which is found to compensate for the impact on CO2 emissions of income changes. The results confirm the empirical relevance of energy efficiency improvements for the mitigation of CO2 emissions. The method developed in this chapter further enables the separate assessment of non-economic behavioural factors which according to the results exert a non-trivial influence on CO2 emissions. Secondly, having empirically confirmed the relationship between energy efficiency improvements and CO2 emission at the macro level in Chapter 2, we investigate potential underlying drivers of energy efficiency improvements taking into account potential asymmetric effects of energy price change in Chapter 3. This is crucial for designing effective and efficient policy measures that can promote energy efficiency. In addition to the Index Decomposition Analysis used to estimate the economy-wide energy efficiency in Chapter 2, we also use Stochastic Frontier Analysis and Data Envelop Analysis as alternative methods. The driving factors are examined using static and dynamic panel model methods that account for both observed and unobserved country heterogeneity. The application for 32 OECD countries shows that none of the three methods leads to correspondence in term of ranking between energy efficiency estimates and energy intensity at the country level corroborating the criticism that energy intensity is a poor proxy for energy efficiency. The panel-data regression results using the results of the three methods show similarities in the impacts of the determinants on the energy efficiency levels. Also, we find insignificant evidence of asymmetric effects of total energy price but there is proof of asymmetry using energy specific prices. Thirdly, in Chapter 4 we offer an improved understanding of the impacts to expect of abolishing fuel price subsidy on fuel consumption, and also of the welfare and distributional impacts at the household level. We develop a two-step approach for this purpose. Key aspect of the first step is a two-stage budgeting model to estimate various fuel types elasticities using micro-data. Relying on these estimates and the information on households expenditure shares for different commodities, the second step estimates the welfare (direct and indirect) and distributional impacts. The application for Nigeria emphasises the relevance of this approach. We find heterogeneous elasticities of fuel demand among household groups. The distributional impact of abolishing the kerosene subsidy shows a regressive welfare loss. Although we find a progressive loss for petrol, the loss gap between the low- and high-income groups is small relative to the loss gap from stopping kerosene subsidy, making the low-income groups to suffer a higher total welfare loss. Finally, from the highlighted results, we draw the following concluding remarks in chapter 5. Energy efficiency appears a key option to mitigate CO2 emissions but there is also a need for additional policies aiming for behavioural change; energy specific prices and allowing for asymmetry in analysing the changes in energy efficiency is more appropriate and informative in formulating reliable energy policies; the hypothesis that only the rich would be worse-off from fuel subsidy removal is rejected and the results further suggest that timing of the fuel subsidy removal would be crucial as a higher international oil price will lead to higher deregulated fuel price and consequently, larger welfare loss.
153

Ekonomické aspekty větrné energetiky / The Economics of Wind Energy

Ryvolová, Ivana January 2005 (has links)
The presented work examines the special characteristics of electricity produced by the wind as a renewable resource into which considerable hopes are being placed. Production of electricity from wind, as well as from other renewable sources, is a subject of many legislatively enshrined preferential rules. These subsidies and regulatory provisions help the energy producers but represent additional costs to every final customer and tax payer. The aim of this work is to analyse the key arguments of wind energy advocates, which are 1) economic advantage of this production due to zero costs for 'fuel' and 2) negligible burden on the environment due to zero carbon dioxide emissions. The work takes into account all aspects of wind energy production, including their financial and extra-financial implications, and shows their indefensibility in economic terms and in terms of environmental protection. Besides, I have attempted to identify institutional aspects and forms of government which is known to give interest groups a chance to succeed in their rent-seeking activities and as a result allow prosperity of the above-mentioned ineffective energy production. Attention is also paid to the observation that, given the specific technological features of electricity production from the wind, it is not possible to fully apply the conclusions of a traditional theory of economic regulation onto the current position of key players in the electricity market.
154

Optimisation et gestion des risques pour la valorisation de la flexibilité énergétique : application aux systèmes d’eau potable / Optimization and risk management for energy flexibility development : application to drinking water systems

Mkireb, Chouaïb 03 July 2019 (has links)
Dans un contexte de croissance démographique dans lequel certaines ressources naturelles sont de plus en plus limitées, une gestion optimisée et conjointe des réseaux publics de l’eau et de l’électricité s’impose. L’ouverture progressive des marchés de l’électricité à la concurrence et les changements de réglementation dans plusieurs pays ont contribué au développement des mécanismes de la flexibilité de la demande, permettant d’impliquer directement les consommateurs dans la gestion de l’équilibre offre-demande du réseau électrique. Les systèmes d’eau potable, étant de grands consommateurs d’électricité, disposent d’une flexibilité grâce à la présence d’ouvrages de stockage d’eau (bâches et réservoirs) et de pompes à vitesse variable. Cette flexibilité, souvent exploitée uniquement à des fins de sécurisation des demandes en eau, peut être valorisée pour permettre une meilleure gestion de l’équilibre du réseau électrique. L’objectif de cette thèse est l’évaluation des valeurs économiques et écologiques relatives à l’intégration de la flexibilité des systèmes d’eau potable dans la gestion opérationnelle du système électrique français. Une étude de l’architecture des marchés de l’électricité en France est d’abord menée pour identifier les mécanismes de flexibilité de la demande les plus adaptés aux contraintes d’exploitation des systèmes d’eau. Des modèles mathématiques d’optimisation sont ensuite proposés et résolus à travers certaines heuristiques, en intégrant les incertitudes relatives aux consommations d’eau, aux prix des marchés ainsi qu’à la disponibilité des équipements de pompage. Les résultats numériques, discutés en se basant sur trois systèmes d’eau potable réels en France, intègrent les aspects économiques (en considérant les risques associés), opérationnels et écologiques. Des réductions importantes des coûts d’exploitation des systèmes d’eau sont estimées à travers la valorisation de l’énergie non consommée pendant les moments de pointe sur le marché spot de l’électricité. En parallèle, la considération des incertitudes permet de sécuriser l’opération des systèmes d’eau en temps réel, et de maîtriser les risques économiques relatifs à l’équilibrage du réseau électrique. De plus, des réductions importantes des émissions de CO2, estimées à environ 400 tonnes par jour en France, peuvent être réalisées en réduisant les volumes d’électricité issus des sources fossiles. / In a context of demographic growth in which natural resources are more and more limited, optimized management of water and power networks is required. Changes in electricity markets regulation in several countries have recently enabled effective integration of Demand Response mechanisms in power systems, making it possible to involve electricity consumers in the real-time balance of the power system. Through its flexible components (variable-speed pumps, tanks), drinking water systems, which are huge electricity consumers, are suitable candidates for energy-efficient Demand Response mechanisms. However, these systems are often managed independently of power system operation, for both economic and operational reasons. In this thesis, the objective is the evaluation of the economic and the ecological values related to the integration of drinking water systems flexibility into power system operation through french demand response mechanisms. An analysis of the architecture of french electricity markets is first conducted, allowing to target the most suitable demand response mechanisms considering water systems operating constraints. Some mathematical models to optimize water systems flexibility are then proposed and solved through original heuristics, integrating uncertainties about water demands, market prices and pumping stations availability. Numerical results, which are discussed using three real water systems in France, integrate the economic aspects inclunding risks, operational and ecological aspects. Significant reductions in water systems operating costs are estimated through the optimization of demand response power bids on the French spot power market during peak times. In parallel, uncertainties consideration secures the operation of water systems in real time, and makes it possible to manage economic risks related to the power grid balancing. In addition, significant savings in CO2 emissions, estimated to around 400 tons per day in France, can be achieved by reducing electricity production from fossil sources.
155

A systematic approach to assess the relocation of the business centres to a logistics platform: A case study on DHL Freight AB (Sweden)

Rozario, Jewel Augustine, Hamid, Osman Abdelkader January 2018 (has links)
The relocation of logistic companies’ from the inner centres to the logistic platforms significantly affects both the supply chain management and the urban sustainability development. Recently the concept of city logistics and intermodality has received a significant attention from both academics and decision makers. City logistics play a pivotal role to ensure the liveability of urban areas but, in parallel, urban freight transport also has a significant effect on the quality of life in the urban settings. Optimization of urban freight transportation have an important input in the context of sustainability and liveability of cities and urban areas reducing traffic congestion, decreasing road accidents, alleviating CO2 emissions and noise impacts. The purpose of this thesis is to evaluate the relocation of a case logistics company from the city centre to a suburban area. To do this, a wide range of literature reviews pertaining the influence of peripheral logistics platform on the city sustainability were investigated. It seems that there are not well-defined models which can make a comprehensive and quantitative assessment in the context of sustainability for the relocation of business premises. Further investigation was done by conducting a case study on DHL, field observation of traffic flow. Based on all the collected information from the relevant sources, a mixed methods research was applied including a qualitative approach and a quantitative approach. A systematic approach was therefore developed in the context of sustainable development which can be used as an assessment tool for the major factors that enlighten the decision makers to consider the relocation of the logistics companies. A systematic approach was developed by this thesis which facilitates the assessment of key factors that impact the relocation decision in the context of all the three sustainable aspects: economic, social and environmental development. These impacts represent traffic congestion, time and distance of transportation, emission, cost optimization and transport mobility.
156

Politiques économiques publiques pour limiter les émissions de CO2 liées à l’usage des véhicules particuliers / Public economic policies to limit CO2 emissions from car use

Meurisse, Bénédicte 30 November 2015 (has links)
Cette thèse porte sur les instruments de politique publique permettant de réduire les émissions de CO2 liées à l’usage des véhicules particuliers. La mise en place de ces instruments est légitime et nécessaire compte tenu de la contribution de ces véhicules au changement climatique (17% des émissions de CO2 en France en 2010). Dans le cadre d’une modélisation théorique en équilibre partiel et statique du marché automobile, les travaux considèrent deux leviers de réduction d’émissions : l’amélioration de la performance énergétique des véhicules et la diminution des distances parcourues. Dans un premier Chapitre consacré à l’analyse côté offre du système automobile, la question de recherche est de déterminer si, d’une part, une coopération entre acteurs de la filière automobile conduit à la production de véhicules plus économes en carburant qu’en l’absence de coopération, et d’autre part, si cette coopération est un substitut ou non à l’intervention publique. L’impact de la demande de véhicules économes en carburant sur les décisions d’investissement et de coopération des producteurs est démontré, ce qui justifie la mise en place d'outils de politique publique stimulant la demande. Aussi, le deuxième Chapitre est consacré à l’analyse de la demande de véhicules et de kilomètres. L’accent est mis sur l’interdépendance entre ces deux demandes, qui est à l’origine du phénomène bien connu d’effet rebond. Il est question d’étudier l’impact de cet effet rebond sur l’efficacité des taxes différenciées à l’achat et des taxes à l’usage des véhicules. Enfin, l’ambition du dernier Chapitre est tenir compte des effets de ces instruments sur l’utilité des ménages et le profit pour la filière automobile. L’objectif plus large est de déterminer si les décideurs publiques sont à mêmes de lutter contre les émissions de CO2 des véhicules tout en augmentant le bien-être de la population et la croissance économique. / This Thesis analyses public economic policies enabling to reduce CO2 emissions from car use. Implementing these tools is legitimate and necessary because of the high contribution of passenger vehicles to climate change (17% of CO2 emissions in France in 2010). Within a partial and static equilibrium model of the car market, the present research considers two distinct levers to cut CO2 emissions from car use: the improvements of passenger vehicles energy-efficiency, and a reduction in miles driven. In the first Chapter dedicated to an analysis of the supply-side of the automotive system, the research question consists in investigating on the one hand whether a cooperation among actors of the automotive sector leads to the production of vehicles that are less fuel-consuming than without the cooperation; and on the other hand whether this cooperation could be a substitute to a policy intervention. The impact of the demand for low fuel-consuming vehicles on the producers’ decision to invest and to cooperate is demonstrated; this justifies the implementation of policy tools stimulating demand. Hence, the second Chapter is dedicated to an analysis of the demand for vehicles and kilometres. Emphasis is placed on the interdependency between car choice and car use, which is at the root of the well-known phenomenon of rebound effect. The aim is to study the impact of that rebound effect on the efficiency of differentiated car purchase taxes and car use taxes. Lastly, the ambition of the last Chapter is to take the impacts of the latter pricing tools on households’ utility and automotive sector’s profit into account. More generally, the purpose is to investigate whether public decision-makers are able to mitigate CO2 emissions from car use while improving households’ well-being and economic growth.
157

Essays on the relationship between co2 emission and income global / Ensaios sobre a relaÃÃo entre emissÃo de co2 e a renda global

Guilherme Diniz Irffi 30 November 2011 (has links)
Banco do Nordeste do Brasil / The company apparently always ignored (or did not spend enough attention) externalities of economic activity harmful to the environment and, consequently, is facing its possible effects in recent decades. Recently, now more conscious of their actions, their continued growth policies are usually formulated taking into account the growth the trade-off between economic growth and environmental preservation cluttered, given that "the agenda" is to combine increased income with sustainability and environmental preservation. Thus, this thesis investigated the relationship between CO2 emissions and economic activity, considering an overall look from the second half of the twentieth century. However, it is used as a motto the literature of economic growth by considering that the relationship above can be analyzed from the Environmental Kuznets Curve, the estimation of the trend of CO2 emission intensity and the analysis of convergence Emission CO2pc. According to the results achieved by three chapters, one can say that to reduce the level of CO2 emissions and mitigate the effects of global warming we need to establish a new regime of CO2 emission quotas with more countries than what has been agreed with the PQ and still contemplate developing countries like China, Ãndia, MÃxico and Ãfrica do Sul At the same time, we must establish a system of taxation for GHG emissions in order to achieve the desired goals of stabilizing and subsequently reduce the emission levels more easily. Moreover, it is necessary that quotas and taxation of CO2 emissions are set from the current level of emissions and the speed of convergence for clubs highest emission level. However, there must be differentiated quotas schemes for the rich countries and developing countries, so allow them to reach the income levels of rich countries. The differentiated regime is necessary because the effects of global warming on society in the XXI century and elevations are consequences of the gas atmosphere during the eighteenth and nineteenth centuries. Therefore, it is for developed countries to further reduce CO2 emissions, according to their historical emissions. However, less developed nations can not fail to participate in this system and also is a need to reconcile economic growth with environmental preservation in such a way to mitigate the effects of global warming on future generations. Another measure that tends to be efficient in combating global warming is to support the development of alternative energy sources with low emission intensity, so increasing the speed of convergence for economies with low GHG emissions. That is, we must achieve energy efficiency from the use of clean energy (less carbon-intensive) and, for that necessarily need to replace fossil fuels. Moreover, it is necessary to transfer technologies with low carbon emissions of developed countries to developing nations in order to generate a global welfare, since this measure tends to increase speed of convergence to a low- CO2 emissions. / As sociedades aparentemente sempre ignoraram (ou nÃo despenderam atenÃÃo suficiente) as externalidades da atividade econÃmica danosas ao meio ambiente e, como consequÃncia, vem enfrentando seus possÃveis efeitos nas Ãltimas dÃcadas. Recentemente, agora mais consciente de suas aÃÃes, suas polÃticas de continuidade do crescimento sÃo geralmente formuladas levando-se em consideraÃÃo o crescimento o trade-off entre crescimento econÃmico desordenado e preservaÃÃo ambiental, haja vista que âa ordem do diaâ à conciliar aumento da renda com sustentabilidade como a preservaÃÃo do meio ambiente. Neste sentido, esta Tese investigou a relaÃÃo entre as emissÃes de CO2 e a atividade econÃmica, considerando um aspecto global a partir da segunda metade do sÃculo XX. No entanto, utiliza-se como mote a literatura de crescimento econÃmico por considerar que a relaÃÃo supracitada pode ser analisada a partir da Curva de Kuznets Ambiental, da estimaÃÃo da tendÃncia da Intensidade de EmissÃo de CO2 e da anÃlise de ConvergÃncia de EmissÃo de CO2 per capita (CO2pc). De acordo com os resultados alcanÃados pelos trÃs capÃtulos, pode-se dizer que para reduzir o nÃvel de emissÃo de CO2 e mitigar os efeitos do aquecimento global à preciso estabelecer um novo regime de cotas emissÃo de CO2 com mais paÃses do que o que foi acordado com o Protocolo de Quioto e, ainda, contemplar os paÃses em desenvolvimento como China, Ãndia, MÃxico e Ãfrica do Sul. Ao mesmo tempo, à preciso estabelecer um sistema de tributaÃÃo para as emissÃes de gases de efeito estufa (GEE), a fim de permitir alcanÃar os objetivos de estabilizar e, posteriormente, reduzir os nÃveis de emissÃo de maneira mais fÃcil. AlÃm disso, à preciso que as cotas e a tributaÃÃo de emissÃo de CO2 sejam definidas a partir do nÃvel atual de emissÃo e da velocidade de convergÃncia para clubes de maior nÃvel de emissÃo. No entanto, deve haver regimes de cotas diferenciadas para os paÃses ricos e os paÃses em desenvolvimento, de tal maneira a permitir que estes alcancem os nÃveis de renda dos paÃses ricos. O regime diferenciado se faz necessÃrio porque os efeitos do aquecimento global sobre a sociedade nos sÃculo XX e XXI sÃo consequÃncias dos gases alÃados a atmosfera terrestre durante os sÃculos XVIII e XIX. Por isso, cabe aos paÃses desenvolvidos a maior reduÃÃo das emissÃes de CO2, em funÃÃo do seu histÃrico de emissÃo. Todavia, as naÃÃes menos desenvolvidas nÃo podem deixar de participar deste sistema e, ainda, à necessÃrio conciliar crescimento econÃmico com preservaÃÃo ambiental de tal forma a mitigar os efeitos do aquecimento global sobre as futuras geraÃÃes. Outra medida que tende a ser eficiente ao combate do aquecimento global à subsidiar o desenvolvimento de fontes alternativas de energia com baixa intensidade de emissÃo, de tal modo a aumentar a velocidade de convergÃncia para economias de baixa emissÃo de GEE. Ou seja, à preciso alcanÃar a eficiÃncia energÃtica a partir do consumo de energia limpa (menos intensiva em emissÃo de carbono) e, para isto, necessariamente, à preciso substituir os combustÃveis fÃsseis. AlÃm do mais, se faz necessÃrio a transferÃncia de tecnologias com baixa emissÃo de carbono dos paÃses desenvolvidos para as naÃÃes em desenvolvimento a fim de gerar um bem-estar global, uma vez que esta medida tende a aumentar velocidade de convergÃncia para uma economia de baixa emissÃo de CO2.
158

A hipótese da curva de kuznets ambiental global e o protocolo de Quioto

Carvalho, Terciane Sabadini 15 December 2008 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-17T13:34:11Z No. of bitstreams: 1 tercianesabatinicarvalho.pdf: 2411280 bytes, checksum: b3e6a12356189399e279b23c9217ee6f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-25T11:55:03Z (GMT) No. of bitstreams: 1 tercianesabatinicarvalho.pdf: 2411280 bytes, checksum: b3e6a12356189399e279b23c9217ee6f (MD5) / Made available in DSpace on 2016-10-25T11:55:03Z (GMT). No. of bitstreams: 1 tercianesabatinicarvalho.pdf: 2411280 bytes, checksum: b3e6a12356189399e279b23c9217ee6f (MD5) Previous issue date: 2008-12-15 / As questões sobre o meio ambiente, ano após ano, vêm desempenhando um destacado papel no debate global sobre o futuro do planeta. Devido à liberação de enormes quantidades de CO2 na combustão de energias fósseis, as suas emissões são classificadas como uma das forças motrizes por trás do fenômeno do aquecimento global. Em todo o mundo, as emissões dos gases de “efeito estufa” (GEE) estão aumentando, apesar dos esforços comuns para implementar acordos internacionais, como o Protocolo de Quioto. Nesse contexto, esta dissertação visa investigar a hipótese da Curva de Kuznets Ambiental (CKA) global e a sua relação com o Protocolo de Quioto. Portanto, um de seus objetivos é verificar se existe uma relação na forma de U invertido entre um índice de degradação ambiental global (emissões de CO2 per capita) e o crescimento econômico (medido pelo PIB per capita) para uma amostra de 167 países durante o período de 2000-2004, utilizando um modelo de efeitos fixos com dependência espacial. Outro objetivo desta dissertação é avaliar o papel do Protocolo de Quioto como uma política global, a fim de reduzir as emissões. Para isso, uma variável dummy, representando os países que ratificaram o Protocolo, é adicionada do lado direito da regressão. Além disso, mais três variáveis são colocadas no lado direito da regressão: nível de comércio, consumo de energia e densidade populacional. Os resultados da Análise Exploratória de Dados Espaciais (AEDE) revelaram que as emissões de CO2 per capita não são distribuídas aleatoriamente, bem como identificou uma série de países que emitem mais do que os outros países: Estados Unidos, Canadá, Austrália, Barein, Brunei, Kuwait, Luxemburgo, Emirados Árabes Unidos, Trinidad e Tobago e Aruba. A AEDE encontrou a existência de clusters, mostrando que o padrão Baixo-Baixo ocorre principalmente nos países mais pobres africanos e asiáticos, enquanto o padrão Alto-Alto aparece essencialmente nos países europeus e países do sudoeste asiático. Os resultados econométricos, a princípio, sugerem a existência de uma CKA na forma de “N” e não de “U” invertido, encontrando os seguintes “pontos de inflexão”: US$ 12.262,44 e US$ 27.083,33. As demais variáveis explicativas também apresentaram os sinais esperados e todas exibiram um coeficiente altamente significativo. Cerca de 80% da amostra não possuem renda acima do ponto de inflexão calculado, ou seja, a grande maioria dos países se encontraria na primeira parte ascendente da curva, revelando que no intervalo de renda observado para os 167 países, muitos exibem uma curva monotonicamente crescente. Isso parece confirmar e ilustrar a natureza global do impacto do dióxido de carbono, revelando que há pouco incentivo para as nações tomarem ações unilaterais para reduzir suas emissões, e que ações multilaterais estão sendo desenvolvidas lentamente. Outra questão importante é o coeficiente negativo e estatisticamente significativo para a variável dummy dos países que ratificaram o Protocolo de Quioto, revelando a importância de acordos internacionais na redução do montante global das emissões de carbono per capita. Portanto, o crescimento econômico sozinho não pode substituir políticas que aspirem a redução das emissões de CO2. Este resultado sugere que políticas internacionais podem ajudar a reduzir as emissões de GEE, mas é preciso que mais países se comprometam nessa redução. Portanto, crescimento econômico por si só não garante a cura para os problemas relacionados ao meio ambiente. As políticas ambientais têm papel fundamental na inversão da trajetória dos poluentes que seguem a CKA. / Over the years environmental issues have been playing a remarkable role in the global debate about the Earth future. Due to the release of huge amounts of CO2 in the combustion of fossil fuels, its emissions are classified as one of the driving forces behind the global warming phenomenon. Worldwide, emissions of the "greenhouse effect" gases (GHG) are increasing, despite the joint efforts to implement international agreements like the Kyoto Protocol. In this context, the present dissertation is aimed at investigating the Global Environmental Kuznets Curve (EKC) hypothesis and its relationship with the Kyoto Protocol. Therefore, one of its objectives is to verify whether there is an inverted U shaped relationship between an index of global environmental degradation (per capita CO2 emissions) and economic growth (measured by per capita GDP) for a sample of 167 countries over the period 2000-2004, using a fixed effect model with spatial dependence. Another objective of this dissertation is to evaluate the role of the Kyoto Protocol as a global policy in order to reduce emissions. To do so, a dummy variable, representing the countries that have ratified the Protocol, is put in right hand of the regression. Besides, another three variables are inserted in the right hand of regression: the trade level, energy consumption and population density. The findings from Exploratory Spatial Data Analysis (ESDA) revealed that per capita CO2 emissions are not randomly distributed, as well as identified a number of countries that emit more than the other countries, namely, United States, Canada, Australia, Bahrain, Brunei, Kuwait, Luxembourg, United Arab Emirates, Trinidad and Tobago and Aruba. The ESDA analysis found the existence of clusters, showing that the low-low pattern occurs mainly in the poorest countries Asian and African, whereas the High High pattern appears mainly in European countries and countries in Southeast Asia. The econometric results, in principle, suggest the existence of a CKA in the form of "N" rather than "U" inverted, finding the following "turning points": US$ 12,262.44 and US$ 27,083.33. The other explanatory variables also showed the expected signs and all exhibited a highly significant coefficient. Around 80% of the sample did not have income above the “turning point” calculated, that is, the vast majority of countries are in the first upward part curve, revealing that in the range of income observed for the 167 countries, many have a curve monotonically increasing. This seems to confirm and illustrate the global nature of the carbon dioxide impact, revealing that there is little incentive for nations takes unilateral actions to reduce their emissions, as well as multilateral actions are being developed slowly. Another important issue is the negative coefficient, and statistically significant, for the dummy variables of the countries that have ratified the Kyoto Protocol, showing the importance of international agreements on reducing the overall amount of per capita carbon emission. Therefore, economic growth alone cannot replace policies that aspire to reducing CO2 emissions. This result suggests that international policies can help reduce GHG emissions, but we need more countries to commit such reduction. Therefore, economic growth alone does not guarantee a cure for the problems related to the environment. Environmental policies have key role in reversing the trajectory of pollutants that follow the CKA.
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Estratégias para a minimização da emissão de CO2 de concretos estruturais. / Strategies for the minimization of CO2 emissions from concrete.

Vanessa Carina Heinrichs Chirico Oliveira 29 May 2015 (has links)
A maior parte das emissões de CO2 do concreto origina-se na produção do cimento. A estratégia tradicional de minimização da pegada de CO2 tem privilegiado o grau de substituição do clínquer. O trabalho examina o impacto dessa estratégia e também a influência da escolha do fornecedor de cimento sob a ótica de sua matriz energética, a variação do consumo de cimento para concretos de mesma resistência e do desvio padrão do processo produtivo de acordo com o controle do processo de produção do concreto. O método de trabalho inclui dados de revisão bibliográfica, normalização técnica e dados de central de concreto. A estratégia tradicional de escolha do tipo de cimento baseando-se em seu teor de clínquer mostra-se incompleta, pois há uma grande variação e sobreposição dos teores de clínquer permitidos nas normas técnicas brasileiras. No momento atual estima-se que a indústria cimenteira nacional utilize praticamente toda a escória de alto forno gerada no país e a quase totalidade das cinzas de melhor qualidade. Dessa forma, aumentando a demanda de cimento, a produção de clínquer aumenta, e o teor de adições no clínquer diminui dentro das extensas faixas permitidas pelas normas técnicas. Nesse cenário, a seleção de um tipo de cimento em detrimento de outro pode reduzir o impacto de uma obra específica, embora não traga necessariamente benefícios ambientais para o país. A troca da matriz energética por carvão vegetal de madeira de florestas plantadas pode minimizar a parcela de emissões provenientes de combustíveis do cimento, diminuindo a emissão de 350 kg para 10 kg de CO2 por tonelada de clínquer produzida. A eficiência do processo de formulação do concreto apresenta grande potencial para diminuir a quantidade de cimento utilizada no concreto, diminuindo, assim, as emissões totais de CO2 do concreto. Os dados levantados apontam uma variação de consumo de cimento de mais de 100% para concretos de mesma resistência. A influência do desvio padrão das condições de produção apresenta potencial menor para a diminuição das emissões, diminuindo no máximo 13% o consumo de cimento no concreto. A combinação das quatro estratégias estudadas demonstra a complexidade da emissão do concreto e o grande potencial para mitigar suas emissões de CO2. A necessidade de informações específicas sobre a emissão dos cimentos, seu teor de clínquer e sua matriz energética, uma técnica de dosagem otimizada e um controle das condições de produção do concreto demonstram que há, tanto para fornecedores de matérias primas do concreto quanto para os usuários e produtores do concreto, muito a ser feito para minimizar as emissões deste material tão consumido. / Most of concretes CO2 emissions originate from cement production. The traditional strategy for minimizing the CO2 footprint of concrete has favored the degree of clinker replacement. This paper examines the impact of this strategy and also the influence of the choice of the cement supplier based on the fuel composition in cement production, the variation of cement usage in concretes of the same strength and the standard deviation of the production process of concrete based on the control of its production process. The method of work uses data from literature, technical standards and data from a concrete central. The traditional strategy of the choice of cement type based on its clinker content is insufficient due to the extensive and overlapping clinker content range of different cement types allowed in Brazilian technical standards. At the present time, it is estimated that the cement industry utilizes all of the blast furnace slag generated in the country and nearly all quality fly ash. Consequently, if there is an increase in the demand for cement, there is an increase in clinker production, and the rate of additions to the clinker decreases, respecting the extensive limits permitted by technical standards. In this scenario, the selection of blast furnace slag cement and fly ash cement does not necessarily offer environmental benefits to the country as a whole and does not demonstrate a global impact, despite the possibility of benefiting specific construction sites. The substitution of the fuel mix for coal from planted forest wood can lower the portion of cement emissions due to fuel burning from 350 kg to 10 kg of CO2 per tonne of clinker produced. The efficiency of the concrete mix formulation shows great potential to lower the amount of cement usage in concrete, thus lowering the total CO2 emissions of concrete. The data presented point to a variation of more than 100% of cement content in concretes of the same strength. The influence of the standard deviation of the production process shows smaller impact on lowering concrete CO2 emissions shows that there is a maximum potential of 13% of lowering cement content in concrete. The combination of the four strategies studied demonstrates the complexity of concretes emissions and the great potential for mitigating its CO2 emissions. The need for information on cements specific emissions, its clinker content and fuel mix, the concrete mix formulation and the variability of the production process of concrete show that there is, for concrete raw material suppliers as well as concrete producers and users, a lot to be done to minimize the emissions of this widely consumed material.
160

An Empirical Assessment of the N-Shaped Environmental Kuznets Curve Hypothesis / En empirisk utvärdering av hypotesen om den N-formade miljökuznetskurvan

Allard, Alexandra, Takman, Johanna January 2017 (has links)
In order to combat global warming and climate change issues and facilitate economic prosperity in the same time, it is important to understand the possible tradeoffs between economic growth and environmental degradation. In this thesis, we evaluate the hypothesis of an N-shaped environmental Kuznets curve (EKC). Using panel data analysis, we investigate the relationship between CO2 emissions, GDP per capita, renewable energy consumption, technological development, trade, and institutional quality for 74 countries over the period of 1994 to 2012. We find (i) evidence for the Nshaped EKC when using pooled OLS regressions for all income groups but upper-middleincome countries; (ii) heterogeneous results regarding the N-shaped EKC across income groups and quantiles when using quantile regressions; and (iii) a clear and consistent negative relationship between renewable energy and CO2 emissions, indicating the importance of promoting greener energy to combat climate change. / För att bekämpa klimatförändringar och samtidigt möjliggöra ekonomiskt välstånd är det viktigt att förstå de möjliga avvägningarna mellan ekonomisk tillväxt och miljöförstöring. I denna uppsats utvärderar vi hypotesen om en N-formad miljökuznetskurva (EKC). Med hjälp av paneldataanalys undersöker vi förhållandet mellan koldioxidutsläpp, BNP per capita, förnybar energi, teknologisk utveckling, internationell handel och institutionell kvalitet för 74 länder under perioden 1994 till 2012. Vi finner (i) bevis för en N-formad EKC för alla inkomstgrupper förutom övre medelinkomstländer när poolad OLS används som skattningsmetod; (ii) heterogena resultat gällande en N-formad EKC, både mellan och inom de olika inkomstgrupperna, när vi använder oss av kvantilregressioner; och (iii) ett tydligt och konsekvent negativt förhållande mellan förnybar energi och koldioxidutsläpp, vilket pekar på vikten av att främja grönare energi för att kunna bekämpa klimatförändringar.

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