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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estimation of carbon emissions from municipal solid waste and determination of the impact of recycling on emissions

Kilaru, Prabhu Kiran January 2010 (has links)
No description available.
2

A Life Cycle Comparison of Light-Frame Wood and Insulated Concrete Form Building Envelopes: Energy Use and Green House Gases

Matthews, Sherman Authur 01 August 2011 (has links)
Given the building sector’s substantial contribution to global energy use and green house gas (GHG) emissions, it is of great importance that only the most effective building envelopes are utilized. Conventional light-frame wood building envelopes are highly popular due to their ease of construction and building economy; however the life cycle performance of the building envelope is often overlooked when this selection is made. Although insulated concrete form (ICF) building envelopes generally require a substantially higher embodied energy input, it should be considered that improvements during a building’s operation phase can offers significant energy returns, ultimately reducing the building’s life cycle energy use and GHG intensity. Therefore, an assessment is conducted regarding the life cycle energy use and GHG intensity of the ICF building envelope, in addition to two light-frame wood building envelopes; the average light wood frame envelope (U.S. Department of Energy, 2007), and a more highly insulated wood frame envelope. The operation phase of the building envelopes proves to be of greatest significance, as it is attributed to 95- 97% of the total life cycle energy use, and 93-96% of life cycle GHG emissions, assuming a 100 year life cycle. Ultimately, the life cycle performance of the ICF building envelope is superior to the two wood frame envelopes due to its improvements in the operation phase. The ICF building envelope has a life cycle energy requirement of 11% to 14% less than the two light-frame wood envelopes, and a 10% to 12% lower life cycle GHG intensity. Although the increased thermal resistance certainly contributes to the superior life cycle performance of the ICF envelope, the improved infiltration leakage area of the envelope is key to its operational performance, and subsequently to its improved life cycle performance. End of life energy use for the demolition, recycle, and disposal of the building envelopes is nearly negligible, as it is attributed to less than 0.3% of the life cycle energy for any of the envelope scenarios.
3

Optimal Generation Expansion Planning Strategy for the Utility with Independent Power Producer Participation and Green House Gas Mitigation

Liao, Bo-xiang 29 June 2009 (has links)
Thermal power plants dominate electric power generation in Taiwan, which causes high Green House gases (GHG) emissions. CO2 is the most important greenhouse gas that cause global warming and sea-level to rise. This paper faces the relationship between CO2 limitation and power generation expansion planning (GEP) for the utility. Modify Particle Swarm Optimization (MPSO) is presented to determine the generation expansion planning strategy of the utility with independent power providers (IPPs). The utility has to take both the IPPs¡¦ participation and environmental impact into account when a new generation unit is expanded. This problem also takes into account the CO2 reduction and reliability issues, while satisfying all electrical constraints simultaneously from the supply point of view. MPSO scheme was improved to avoid getting a premature answer. Testing results shows that MPSO can offer an efficient way in determining the generation expansion planning. Generation expansion planning is an important decision-making activity in a competitive market, all utilities including IPPs need to maximize the profit while meeting the load demand with a pre-specified reliability criterion. In order to achieve the objective, utilities will perform the generation expansion planning to determine the minimal-cost capacity power addition. For better economy and efficiency, they will consider options of either constructing new generating units or purchasing electricity from other utilities or IPPs.
4

Véhicule électrique et forme urbaine : une évaluation prospective / Electric vehicle and urban form : a prospective assessment

Solignac, Manon 17 January 2018 (has links)
Cette thèse s'intéresse à l'évaluation du potentiel et du coût du véhicule électrique comme solution pour réduire les émissions de CO$_2$ dues au transport de passagers en ville. Elle montre comment intégrer les habitudes de déplacement des usagers dans les méthodologies de quantification modifie ces évaluations. Les analyses portant sur le véhicule électrique calculent généralement un potentiel de réduction d'émissions et un coût sans distinguer les spécificités locales des territoires où ce véhicule pourra être mis en place et de l'utilisation qui en découle. Elles ne tiennent pas compte non plus des autres politiques existantes sur ce territoire, notamment de celles jouant sur la structure de la mobilité, à savoir son volume total et son partage modal. Ainsi, les différentes solutions de réduction d'émission de CO$_2$, technologiques d'un côté et portant sur la structure de la mobilité de l'autre, sont le plus souvent discutées de manière indépendante, et les possibles rétroactions de l'une vers l'autre sont peu analysées. Cette thèse vise donc à considérer conjointement l'introduction d'une solution technologique telle que le véhicule électrique et les structures urbaines dans lesquelles elle se déploie. Pour cela, nous développons un modèle de choix de technologies de véhicules des ménages, et l'intégrons à un modèle d'économie urbaine. Nous nous intéressons dans un premier temps, aux caractéristiques spatiales de la ville et donc à l'usage qui est fait de ce véhicule ; puis, dans un deuxième temps, à la mise en œuvre simultanée d'une solution jouant sur la structure de la mobilité pour réduire les émissions : la ceinture verte. Ces deux analyses nous permettent de mettre en évidence, et de quantifier, l'interdépendance d'une action s'appuyant sur la technologie et d'une autre s'appuyant sur la structure de la mobilité. Enfin, dans un troisième temps, nous introduisons l'hétérogénéité des usages ainsi que l'incertitude sur les prix futurs de l'énergie et les coûts futurs des batteries dans un modèle de calcul de la valeur d'option du déploiement du véhicule électrique. Nous montrons que ces deux éléments conduisent à réviser l'évaluation de la valeur d'option à la hausse / This thesis brings precisions on the measure of the emissions reduction potential in cities and the cost of electric vehicle by taking into account users driving patterns. Studies on electric vehicles or other solutions belonging to the "technological lever" compute emissions reduction potential and cost without discerning the local specificities of the areas where it would be used and the use that would be done of these vehicles. These studies don't take into account the other policies implemented in the area, including the ones that operate on a different lever such as the "mobility structure lever" : volume of activity and modal shares. Policies for reducing CO$_2$ emissions are often discussed independently and ignore the possible retroactions. To improve the evaluation of the potential of the electric vehicle, it seems essential to take into account the environment in which it would be developed. We use a urban economics model to first look at the spatial features of the city, and so at the use of this vehicle. Then we compute the impacts of the simultaneous introduction of the electric vehicle and a solution belonging to the "mobility structure lever" : the greenbelt. These two last points allow us to highlight the interdependency of the two action levers : technology and mobility structure. Then we take into account the use of the car by the households and the uncertainty around electric vehicle introduction, to improve the evaluation of the cost of this solution
5

Analysis of green-house gas emission in China / Analys av växthusgasutsläpp i Kina

Li, Yulin January 2017 (has links)
Today China produces most GHG emissions in the world, which continues increasing the average temperature of the Earth. For the purpose of reducing the emission and reaching the peak of GHG emission before 2030, Chinese government promotes several policies, such as developing renewable energy, importing advanced emission reduction technology and encouraging the production and sales of new energy vehicles. In order to estimate the tendency of Chinese GHG emission, a review has been conducted. This review has considered the current Chinese situation, making necessary assumptions and calculating total emission in several relevant sectors independently. By adjusting several key figures, the end result of peak year may be changed. The review has proved that the peak year for Chinese GHG emissions will be 2035 under normal condition. If other optimized factors are considered, the peak year could be moved up.
6

Small Area Power Plant Optimal Planning with Distributed Generations and Green House Gas Reduction

Lin, Chang-ming 27 June 2011 (has links)
In recent years, with the energy shortage, the use of renewable energy is inevitable. With CO2 the most important greenhouse gas causing global warming as well as the increase of population, renewable energy is one way to save energy and reduce carbon emissions. The traditional capacity investment for serving the load in distribution systems usually considered the addition of new substations or expansion of the existing substation and associated new feeder requirement. Nowadays, there are a lots of distributed generations (DG¡¦s) to be chosen. Factors of the choice taken into account will include lower pollution, higher efficiency, higher return rate for construction of distributed power generation systems. This thesis assumes that the distributed generation can be invested for long-term power plant planning. The planning of DG would be investigated from the perspectives of the independent investors. The modified Particle Swarm Optimization is proposed to determine the optimal sizing and sit of DG¡¦s addition in distribution systems with the constrains of CO2 limitation and addition of distributed generation to maximize profits. This thesis deals with discrete programming problem of optimal power flow, which includes continuous and discrete types of variables. The continuous variables are the generating unit real power output and the bus voltage magnitudes, the discrete variables are the shunt capacitor banks and sit problems. The Miaoli-Houlong system of Taiwan power will be used in this thesis for the verification of the feasibility of the proposed method.
7

Impacto da adição de resíduos orgânicos na comunidade microbiana do solo e na emissão de N2O / Impact of organic residues addition in soil microbial community and N2O emissions

Suleiman, Afnan Khalil Ahmad 22 August 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Agricultural lands receive crop and animal residues as option for additional nutrients to replace inorganic fertilizers. Although the idea of discard residues is sustainable, its implementation contributes to the production of greenhouse gases such as nitrous oxide (N2O). However, the impact of disturbances caused by crop wastes on soil microbial community is still not clear. The aim was to study the impact of agricultural residues on the bacterial community accessed by next generation sequencing of nucleics acids. Two field experiments were carried out with the first experiment with the treatments control, mineral fertilizer, slurry and slurry with nitrification inhibitor dicyandiamide (DCD) while the second experiment presented the following treatments: control, sugarcane straw, vinasse and vinasse with sugarcane straw. Nitrous oxide emissions were also analysed. The organic fertilizers were the main drivers on changes in microbial community structure and they affected the microorganisms differently conformable to the applied residue compared with soils with or without fertilizer, but without residues. Slurry application changed the community in the third day of experiment temporarily due to increases in the abundance of Bacteroidetes, Proteobacteria and Firmicutes but the metabolically active microbial community was resilient returning to the original state after 50 days of experiment. The impact of plant residues were visualized in the treatment than microbial dynamics with only straw application modifying the abundance of Bacteroidetes and Beta-Proteobacteria. High proportions of Verrucomicrobia were found in vinasse treatment, whereas Firmicutes were overrepresented in vinasse plus straw treatment. Plants and animal origin residues as slurry with and without DCD, straw and vinasse affected specific groups of microorganisms that participate in nitrogen cycle. Furthermore, phosphorus, iron and nitrogen cycles were altered in plants residues treatments. Different microorganisms were responsible for the same functions in biogeochemical cycles in different treatments with plant residues indicating possible functional redundancy. All agricultural residues amendments also contributed to increase N2O emissions, except for the treatment with DCD which was effective against the nitrification process. In conclusion, the results are important to understand the appropriate crop residues managements in microbial compositions and functions under the current effort of sustainable agricultural practices. / Terras agrícolas tem recebido resíduos de culturas e de animais como opção de fornecimento de nutrientes adicionais em substituição aos fertilizantes inorgânicos. Apesar da ideia do retorno de resíduos produzidos na agricultura ao solo ser sustentável, sua aplicação continua contribuindo para produção de gases de efeito estufa como o óxido nitroso (N2O). Entretanto, o impacto dos distúrbios provocados pelo uso de resíduos agrícolas sobre a comunidade microbiana do solo ainda não são claros. O objetivo deste trabalho foi estudar o impacto do retorno de resíduos produzidos na agricultura como dejetos, vinhaça e palha sobre a comunidade bacteriana do solo acessada por sequenciamento de nova geração de ácidos nucleicos. Foram realizados dois experimentos de campo a curto prazo foram realizados com o primeiro experimento apresentando os tratamentos: controle, fertilizante mineral, dejeto e dejeto com inibidor de nitrificação dicianodiamida (DCD), enquanto o segundo experimento apresentou os seguintes tratamentos: controle, palha de cana-de-açúcar, vinhaça e vinhaça em conjunto com palha de cana-de-açúcar. O efeito das emissões de óxido nitroso também foram analisadas. A adição de resíduos orgânicos apresentou o maior impacto na mudança da comunidade bacteriana do solo e afetaram a presença de microrganismos conforme o resíduo aplicado quando em comparaçao com solos com solos com ou sem fertilizantes, mas sem a aplicaçao de resíduos. A aplicação de dejetos animais afetou a comunidade ao terceiro dia do experimento principalmente devido a um aumento na abundância de Bacteroidetes, Proteobacteria e Firmicutes, mas a comunidade voltou ao seu estado inicial após 50 dias de experimento. O impacto da aplicação de resíduos vegetais vinhaça e palha foi visualizada com a aplicação da palha modificando a abundância de Bacteroidetes e Beta-Proteobacteria. A adição de vinhaça provocou um aumento nas proporções de Verrucomicrobia enquanto Firmicutes foram mais abundantes no tratamento com adição de vinhaça em conjunto com a palha nos 46 dias do experimento. Entre as funções afetadas pela adição de resíduos de origem animal e vegetal, a aplicação de dejetos com e sem DCD, assim como a aplicação de palha e vinhaça, atuaram sobre grupos específicos de microrganismos do ciclo do nirogênio. Além disso, ciclos de fósforo, ferro e nitrogênio foram observados em diferentes tratamentos de resíduos vegetais. Diferentes microrganismos foram responsáveis pelas mesmas funções nos ciclos biogeoquímicos em distintos tratamentos com resíduos vegetais indicando possível redundância funcional. A aplicação de todos os resíduos também contribuiu para o aumento da emissão de N2O, com exceção do tratamento com adição de DCD em que mostrou que o inibidor foi efetivo em retardar o processo de nitrificação. Os resultados são importantes para entender o gerenciamento dos resíduos das culturas nas comunidades e funções microbianas do solo sob o esforço atual de práticas agrícolas sustentáveis.
8

Effekter på klimat, hydrologi och biologisk mångfald av en potentiell våtmarksrestaurering i ån Sennan, Halmstad Kommun.

Jansson, Joel January 2020 (has links)
1928 beslutades att ån Sennan norr om Karlstorp skulle sänkas, rätas ut och delvis kanaliseras för att öka arealen produktiv jordbruksmark. Men åtgärderna orsakade även flera problem både inom och utanför det område som man undersökte innan genomförandet. Dräneringen ledde till att torvmark torrlades vilket orsakar utsläpp av växthusgaser. Vattnets uppehållstid i landskapet kortades och infiltration till grundvattnet minskades. Den biologiska mångfalden minskade genom habitatförlust, alltså färre livsmiljöer, och även genom ökade mängder lösta organiska ämnen i vattnet. Dessa negativa effekter går att motverka genom restaurering. Höjning av grundvattennivån och igenläggning av diken skulle förbättra hydrologin och förbättra grundvattenbildningen. Återvätning av torvlagren hade minskat utsläppen av växthusgaser och våtmarken hade förlängningen istället kunnat fungera som kolsänka. Restaurering av ån och torvmarken kan bromsa habitatförlusten och skapa nya habitat som med tiden kan bli koloniserade och öka den biologiska mångfalden. Eftersom varje lokal har unika förutsättningar är det är svårt att beräkna hur mycket utsläppen skulle minska, värden på hydrologiska faktorer och till exempel eventuell ökad artrikedom. Aktuell forskning visar att restaurering av torvmarker och vattendrag kan leda till förbättrad hydrologi, minskade utsläpp av växthusgaser och ökad biologisk mångfald, även om det i vissa fall kan ta lång tid innan ekosystemet anpassat sig och de positiva effekterna av restaurering blir märkbara. Med tanke på dagens miljöproblem med klimatförändringar, torka, översvämningar och utarmning av den biologiska mångfalden är restaurering av detta område mycket angeläget. / In 1928 it was decided that the stream Sennan north of Karlstorp would be drained and straightened to increase the area of ​​productive agricultural land. But it also caused several problems both inside and outside the area that were being investigated before implementation. The drainage caused peatland to dry, causing greenhouse gas emissions. Water residence time in the landscape was shortened and groundwater infiltration was reduced. Biodiversity decreased through habitat loss and increased amounts of dissolved organic matter in the water. These negative effects can be counteracted by restoration. Raising the groundwater level and ditch blocking improves hydrology and increases groundwater formation. Rewetting of the peat layers reduces greenhouse gas emissions and the wetland can instead function as a carbon sink. Restoration of the river and peatland reduces habitat loss and creates new habitats that will eventually become colonized and increase biodiversity. Because each site has unique conditions, it is difficult to calculate in what amount emissions would decrease, values ​​of hydrological factors and, for example, possible increased species richness. Recent research shows that restoration of peatlands and streams leads to improved hydrology, reduced emissions of greenhouse gases, and increased biodiversity, although in some cases it may take a long time for the ecosystem to adapt and the positive effects of restoration become noticeable. Given today's environmental problems with climate change, drought, floods and loss of biodiversity, restoration of the affected area is very desirable.
9

EU Food Production and Climate Policy : An analysis of the Farm to Fork Strategy

Håkansson, Elias January 2022 (has links)
This paper analyses the EU’s European Green Deal and the changes to Food production it seeks to implement in its Farm to Fork Strategy, introduced in 2019. Attempting to establish whether or not it will enable them to succeed in meeting their goal of a 55% reduction of Green House Gas Emissions by 2030. The analysis on the EU’s food production system is done using a theory which looks at the production efficiency, the shift of diets and the reduction of food waste that the strategy seeks to implement. Arguing that specific shifts in these categories must be made if the EU’s climate goals are to be met. This is then compared to the actual policies implemented in the Farm to Fork Strategy. The thesis concludes that, while the EU succeeds in its food waste preventions as well as some aspects of its production efficiency, it is lacking in its strategy regarding shifting diets and that, in order to meet its climate goals, substantial shifts will need to be made in this category.
10

Resposta político-econômica às mudanças climáticas: origens, situação atual e incertezas do mercado de créditos de carbono.

Costa, Paulo de Oliveira January 2004 (has links)
p. 1-131 / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-03-21T20:06:49Z No. of bitstreams: 1 2222ss.pdf: 1156633 bytes, checksum: c9980506218597dc5d917b70f73e6b7d (MD5) / Approved for entry into archive by Tatiana Lima(tatianasl@ufba.br) on 2013-04-02T18:59:13Z (GMT) No. of bitstreams: 1 2222ss.pdf: 1156633 bytes, checksum: c9980506218597dc5d917b70f73e6b7d (MD5) / Made available in DSpace on 2013-04-02T18:59:13Z (GMT). No. of bitstreams: 1 2222ss.pdf: 1156633 bytes, checksum: c9980506218597dc5d917b70f73e6b7d (MD5) Previous issue date: 2004 / O objetivo deste ensaio é compreender a formação do mercado internacional de créditos de carbono, como uma resposta político-econômica às mudanças climáticas, e analisar a conveniência e oportunidade da criação de uma política pública financeira local tendente a incentivar o desenvolvimento de projetos de mitigação de emissões. O ensaio revê as razões científicas que amparam as negociações políticas; a perspectiva histórica das negociações sobre mudanças climáticas; os grupos de interesse; os problemas de uso dos bens públicos globais; o Protocolo de Kyoto - sua arquitetura e discussão sobre os custos de cumprimento; o mercado emergente de créditos de carbono e a participação brasileira nesse mercado. A decisão americana de não ratificar o Protocolo reduz a efetividade dele para controlar as emissões de gases de efeito estufa, diminui o tamanho do mercado de créditos de carbono - em quantidades e preços. Há incertezas sobre a sorte do Protocolo depois do primeiro período de comprometimento, 2008-2012. No momento, parece não ser razoável construir uma estratégia financeira para aumentar a participação local nesse mercado. / Salvador

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