• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 6
  • 3
  • 2
  • 1
  • Tagged with
  • 16
  • 16
  • 16
  • 6
  • 6
  • 5
  • 5
  • 5
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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

How Effective is the Kyoto Protocol in Impelling Emission Reduction

Yang, Haoyuan, Zhang, Qian January 2011 (has links)
The Kyoto Protocol is one of the most important international climate change treaties aimed at fighting global warming. On January 1st 2005, the protocol was enforced with its first commitment period 2008-2012. However, the effectiveness of reducing CO2 emission has long been debated. The purpose of this thesis is to empirically as-sess the impact of the Kyoto Protocol on carbon dioxide reduction across countries, whether the protocol led significant difference after entering force in 2005. The data used in this thesis cover 37 Annex B countries and 148 non-annex B countries from 1990 to 2007. The models are constructed on the basis of the various contributing fac-tors to CO2 emissions and the Environmental Kuznets Curve model. The main find-ing is contrary against the result expected. The insignificant dummy variable cannot indicate that there is a “structural break” of CO2 emissions reduction after the Kyoto Protocol was implemented. The conclusion is that political agreements such as Kyoto Protocol cannot show critical effects on reducing carbon dioxide. The underlying main driving factors of CO2 emission are energy use, electricity from coal source, fossil fuel burning, in other words, industrialization. And the technology develop-ments cannot keep in pace with finding a new energy source and effectively control-ling CO2 emissions in the short run.
2

Glass as a Building Element – A Sustainable Approach: A Study of an Existing Academic Building

Jori, Swapnil Shriram 2010 December 1900 (has links)
In the aspects of global sustainability, buildings are known to be one of the largest energy consumers. Though sustainable building construction through technological advances is helping in achieving environment friendly buildings, a considerable amount of energy is also being consumed by existing buildings. While many factors at all different stages of building life are responsible for this, the building material is one of the most important considerations. Glass being the most sensitive building material can lead to high energy consumption in the building if used in an improper way. This study takes this factor into account, and tries to investigate the potential of energy savings in buildings through the simple and basic considerations in design. An energy analysis model of an existing academic building in College Station, Texas was developed using Design Builder computer simulation software. This model was then analyzed for the total amount of energy consumption in the base case. The existing building model was then modified by replacing the glass used for external fenestrations. Latest building codes and standards for the site location, glass properties, and parametric simulation results were taken into consideration. Again the model was simulated for annual energy consumption and the results are noted. This formed the first option for the retrofitting scenario. A hypothetical redesign scenario was also established in which the revision of building orientation was taken into consideration. The building was re-oriented to suit the weather conditions and recommendations by Advanced Energy Design Guidelines (30 percent energy savings over ASHRAE Standard 90.1-1999). The building was then simulated for annual energy consumption. A comparative analysis was performed between the three cases and the study concluded by showing 23 percent savings in the annual fuel consumption, 23.35 percent reduction in CO2 emission of the building and 25 percent reduction in annual solar heat gain under Modified case 1. Modified case 2, however, did not show any further savings due to the form of the building (almost square). However, modified case 1 settings emitted 31.8 percent more CO2 over the Energy Star office building in Texas. This methodology sets up a set of guidelines which can be followed while investigating a building for minimum annual energy consumption.
3

Investigation on solar powered organic Rankine cycle with energy storage, economic and environmental benefits at different climate zones in various buildings types in the United States of America

Hemmati, Hadis 25 November 2020 (has links)
This study investigates the potential of installing an integrated solar powered Organic Rankine Cycle (ORC) with electric energy storage (EES) to provide clean energy to commercial buildings in different climate zones in the US. Reducing the primary energy consumption (PEC), lowering the carbon dioxide emissions (CDE) and increasing the operational cost savings are primary objectives. Firstly, a large office building for eight US climates is studied. The EES is sized to store all the electricity generated by the system. Secondly, the system is studied for sixteen different commercial buildings, in the best climate zone, by considering two operational strategies. Finally, the influence of variable expander efficiency on the system performance is investigated. Results indicate that Phoenix is the best location in the US, among the evaluated locations, to install the ORC-EES. The model for the full-service restaurant shows higher savings and more electricity supply percentage than the other buildings. The model under the variable expander efficiency lowers the yearly PEC by 1.6% and CDE and operational cost savings both by 11%.
4

IMPACT OF ECONOMIC GROWTH ON CARBON DIOXIDE EMISSION IN THE NORTH AND SOUTH AMERICAN COUNTRIES

Okafor, Success Amobi-Ndubuisi 01 December 2022 (has links)
Greenhouse Gas emission increase is largely attributed to carbon dioxide emissions as the major gas causing climate change and atmospheric warming. According to Environmental Kuznets Curve Theory (EKC), the increase in economic growth is expected to reduce the environmental pollution from carbon dioxide emission caused at the beginning stages of economic growth. In this thesis, I examined the impact of economic growth on carbon dioxide emission. The key hypothesis tested in this study is the Environmental Kuznets Curve hypothesis. Data from 1967 to 2016 from over 15 countries in North and South America, published by the World Bank were used. Since EKC posits a non-linear relationship between economic growth (GDP/capita) and Carbon dioxide emission, I used a quadratic component in the regression model. I analyzed the data using the OLS regression as my baseline model. Each country is unique in many respects that are hard to capture by a set of variables in econometrics model. This poses a challenge to estimating an unbiased estimate. Using panel data model allowed controlling for time invariant unobserved country-specific factors that could bias the estimates. I estimated a fixed effect panel regression to examine the relationship between carbon dioxide emissions and economic growth is primarily measured with Gross Domestic Product (GDP) per capita. The results of the fixed effect panel regression showed that all variables are significant, except export and inflation which were not significant. OLS could not solve the issue of heterogeneity among the variables. Estimating country-specific fixed effects model eliminates unobserved heterogeneity across countries and, therefore provides relatively unbiased estimates compared to OLS estimates. The positive correlation between Total CO2 emissions, CO2 emissions from Solid, and CO2 emissions from gas and GDP per capita suggests that carbon dioxide emissions increase as GDP/ capita increases before the turning point. The negative correlation between Total CO2 emissions, CO2 emissions from Solid, and CO2 emissions from gas and GDP per capita squared suggests that there is a polynomial (quadratic) form which is like that of inverted U-shape of the EKC curve. The coefficient, although it is very small, suggests the impact of the negative relationship after the turning point at the vertex of EKC curve is fractional. As expected, the result indicates a higher population causes an increase in total CO2 emissions. The result from CO2 emissions from liquid shows a negative relationship between the dependent variable CO2 emissions from liquid and the independent variable GDP per capita at the highest level of significance. This result is different from that of total carbon dioxide emissions, CO2 emissions from Solid, and CO2 emissions from gas. Carbon emission from liquid looks different from carbon emissions from solid and gas. There are high and constant emission throughout all the years and in all countries used in the analysis. EKC hypothesis is proven to be true for total carbon dioxide emissions, carbon dioxide emission from solid and gas. The hypothesized correlation between GDPs per capita square and CO2 emissions is statistically supported for Total CO2 emission, CO2 emission from solid and CO2 emission from gas. CO2 emissions from Solid, and CO2 emissions from gas and GDP per capita squared suggest that there is a polynomial (quadratic) form which is like that of inverted U-shape of the EKC curve. This proves that EKC model is proven to be true for my data. Policies like population policies can help in increasing growth in GDP per capita and reducing growth in the amount of carbon dioxide emissions. Population policies could play a significant role aimed at mitigating and reducing climate change.
5

Är Ericsson en bekräftelse på Porterhypotesen ? : En fallstudie på Ericsson AB om huruvida hållbarhetsregler utvecklat och drivit på eller begränsat Ericssons innovationstakt och konkurrenskraft för perioden 2008 – 2022.

Ljung, Gustav January 2023 (has links)
Abstract The purpose of the report is to analyze, if the sustainability EU directives in terms of RoHS Directive, REACH Directive and WEEE Directive and the requirement to reduce carbon dioxide emission have influenced or restricted Ericsson's innovation rate, technology development, profitability, and the competitiveness of the company. The study is made as a qualitative and quantitative case study on how Ericsson's innovation capacity, technology development and competitiveness was affected by the requirement to reduce carbon dioxide emission and how the company has acted upon the EU sustainability directives. Part of the investigation was to quantitative verify if it was a correlation between Ericsson total number of patents per year and the company's investment in research and development, and the  carbon footprint of the company. The result of the study should describe if Ericsson is a good example of the Porter hypothesis and by that respond to the research question. Have the sustainability rules in terms of RoHS Directive, REACH Directive and WEEE Directive and reduction of carbon dioxide emission developed and promoted or reduced Ericsson's pace of innovation, technology development, profitability, and the competitiveness?  The conclusion of the study is that Ericsson has increased its investments since 2017 in research and development and for the last three years Gartner have awarded them as the technical leader and ABI Research has awarded the company as the most sustainable company in the telecom industry. Based on Ericsson innovations and technical development, the company has reduced the carbon footprint with 26 % from 2016 to 2022 and has a goal to become emission free by 2040. Ericsson is an example of the narrow version of the Porter hypothesis.
6

Analysis of greenhouse gas emission from reactive materials and its thermodynamics

Lebelo, Ramoshweu Solomon January 2013 (has links)
Thesis (DTech(Mechanical Engineering))--Cape Peninsula University of Technology, 2013 / The environment is polluted by many gases of which carbon dioxide is one of them and unfortunately during the emission of carbon dioxide, oxygen, which is very important for keeping all species alive, is depleted. Increased industrial activities led to more emission of carbon dioxide and ultimately global warming arose as a result of the greenhouse effect. Global warming has resulted with high temperatures and carbon dioxide production in the atmosphere and it was necessary to come up with mathematical modelling to investigate processes that may try to reduce temperature rise, carbon dioxide emission and oxygen depletion in a stockpile of combustible material. The work done in this thesis considered three differential equations, first for temperature behaviour, second for oxygen depletion and third for carbon dioxide emission. The three equations were solved simultaneously for a reactive slab of combustible material. An exothermic reaction in a stockpile of combustible material results due to the reaction of oxygen with reactive hydrocarbon material and the products are usually heat and carbon dioxide. A detailed discussion on this part is given in chapter 1, and also some definitions of terms applied in this work, together with literature review, statement of problem, aim of the study, objectives of the study and methodology are part of the chapter. In chapter 2, the nonlinear partial differential equations governing the process are derived.
7

Possibilities of rewetting agricultural land for decreasing greenhouse gas emission and sustainable adaptation to flooding : -A case study from two sites in Sweden

Lamin, Noore Wazid January 2015 (has links)
The consequence of climate change will be more flooding in some areas and problems with sea-level rise. Drained wetlands and lakes that today are used for agriculture in the future may need to be rewetted because it might be unsustainable to continue to drain them. Rewetting these lands will have many positive effects like for instance decreased greenhouse gas emissions since these lands due to their high organic matter content are emitting a lot of CO2 and N2O. In this study two sites that could become candidates for rewetting have been studied and compared for their CO2 and N2O emissions. This was done by using a method for sampling gases both from a closed chamber and directly from soil. The emission rates were higher for Ramsjön compared to Vesan for both gases that could probably be an effect of season. A strong covariation between the two gases was shown for Ramsjön and the relationship was fairly strong for Vesan this indicates a common process for releasing the two gases. Rewetting these areas would probably have a high potential for saving greenhouse gas emissions and possibly also serve as flood adaptation areas with a high biodiversity and recreational value.
8

Avaliação do ciclo de vida de blocos de concreto do mercado brasileiro: alvenaria e pavimentação. / Life cycle assessment of concrete blocks on the Brazilian market masonry and pavement.

Oliveira, Lidiane Santana 06 July 2015 (has links)
A construção civil é responsável por relevante impacto ao meio ambiente, da extração das materiais-primas até a disposição dos seus resíduos em aterros. A avaliação do ciclo de vida (ACV) é uma ferramenta que possibilita a estimativa dos impactos ambientais potenciais do setor de forma sistemática. A simplificação da ACV, pelo uso de dados secundários e redução do escopo do estudo, facilita sua implementação como ferramenta de promoção da sustentabilidade. O objetivo dessa dissertação é estimar faixas dos cinco principais indicadores do setor de blocos de concreto do mercado brasileiro pela simplificação da ACV: consumo de materiais, energia incorporada, emissão de CO2, água e geração de resíduos. Este estudo foi o piloto do Projeto ACV Modular, iniciativa do Conselho Brasileiro de Construção Sustentável em parceria da Associação Brasileira de Cimento Portland e da Associação Brasileira da Indústria de Blocos de Concreto. O inventário foi desenvolvido com 33 fábricas localizadas em diferentes regiões do Brasil, estas sendo responsáveis por aproximadamente 50% da produção nacional. Os produtos selecionados foram blocos para pavimentação e alvenaria (estruturais e de vedação) considerados mais representativos no mercado. A fronteira do sistema adotada foi do berço ao portão da fábrica. O indicador de consumo de materiais não foi apresentado para garantir a confidencialidade dos dados das empresas, pois o teor de cimento foi dado direto informado no formulário. O indicador de resíduos não pode ser gerado devido a diferentes interpretações adotadas pelos fabricantes ao registrar seus dados. O indicador de água, apesar de incluir todo o consumo informado pela fábrica, apresentou valores muito baixos, alguns próximos a zero. O consumo de cimento, não o teor de clínquer, foi responsável por parcela significativa do CO2 e da energia incorporada do bloco, com participação de 62 a 99% das emissões de CO2. Assim, entre as empresas analisadas, mesmo com igual rota tecnológica, os insumos utilizados, a formulação do concreto, a eficiência de compactação da vibro prensa e o sistema produtivo tiveram maior influência nos indicadores de materiais, energia e CO2. / The civil construction is responsible for significant environmental impact from the extraction of raw materials to the disposal of their waste in landfills. The life cycle assessment (LCA) is a tool that enables the estimative of the potential environmental impacts of a sector systematically. Simplification of LCA, the use of secondary data and reduce the scope of the study, facilitates its implementation as a tool for promoting sustainability. The purpose of this dissertation is to estimate ranges of the five main indicators of the concrete block industry in the Brazilian market by simplifying the LCA: consumption of materials, embodied energy, CO2 emissions, water and waste generation. This study was the pilot of Modular LCA Project, an initiative of the Brazilian Council for Sustainable Construction (CBCS) in partnership with the Brazilian Portland Cement Association (ABCP) and the Brazilian Association of Concrete Blocks Industry (BlocoBrasil). The inventory was raised from 33 factories located in different regions of Brazil, that accounting for approximately 50% of national production. The products selected were paving and masonry blocks considered most representative in the market. The boundary system adopted was from cradle to factory gate. The indicator material consumption has been omitted to ensure the confidentiality of company data, as the cement content was raised directly by the companies. The waste indicator cannot be generated due to different interpretations adopted by companies to register their data. The water indicator, although it includes all the consumption reported by the factory, showed very low values, some near zero. Cement consumption, not the clinker content, accounted for a significant portion of CO2 emission and embodied energy, accounting 62-99% of CO2. Thus, among the analyzed factories, even with the same technological route, the inputs, the concrete formulation, the compression efficiency of vibro press and the production system had a greater influence on indicators of materials, energy and CO2.
9

Nigerian coal power stations : their future in the light of global warming / E.N. Eziukwu

Eziukwu, Emenike Nduaka January 2008 (has links)
Nigeria is presently being faced with a growing electricity demand problem following its population growth rate. The total installed capacity is far less than the current demand for electricity supply. As a way of bridging out this supply gap, the federal government is mobilizing all of its potential energy options. Coal is widely used for power generation in many countries. But today, the continued usage of coal for power generation is being challenged by the disturbing global warming phenomenon. This is due to the quantity of uncontrolled carbon dioxide emission from traditional coal-fired power plants. The aim of this dissertation is to critically analyse the future of the Nigerian coal power stations following the need to do carbon dioxide emission control necessary for ensuring a sustainable environment. Achieving this aim entails the appraisal of environmental regulation standards and cost structures of carbon dioxide (C02) emission reduction options for the coal power stations. Controlling carbon dioxide emission from existing coal power stations requires retrofit system that captures and effectively sequestrates the captured CO2. The cost and performance effect of the CO2 retrofit system on the existing power plant can be simulated with standard computer software models. In this study the lECM-cs computer modelling tool for power plants was used in determining the cost and performance impacts of applying an Amine-based C02 capture system to the Oji river power station in Nigeria. With the lECM-cs model, it was established that reducing C02 emission imposes an additional cost on the power plant which increases the unit cost of electricity generated. This additional cost index requires economic justification for its acceptance. This is due to the need to demonstrate its viability judging from the cost of electricity generated from other sources in the Nigerian economy. For the Oji river case, the station is old and requires extensive renovation. This causes a cost escalation over and above the cost associated with the CO2 sequestration system. As such, Oji coal power station does not have an economic future if C02 emission sequestration becomes obligatory. The future of coal power stations in Nigeria can be considered from two scenarios: one where the current national environmental standard is retained and another where it is revised. The revision classifies CO2 as a pollutant which makes its emission reduction imperative for coal power plants. Under the current standard, building modern large capacity pulverized coal-fired power plants with improved steam cycles should be encouraged. But with the review of the national standard, the focus should be on building new large capacity coal power stations with integrated CO2 emission control. This will ensure an environmentally friendly future for coal power stations in Nigeria. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
10

Nigerian coal power stations : their future in the light of global warming / E.N. Eziukwu

Eziukwu, Emenike Nduaka January 2008 (has links)
Nigeria is presently being faced with a growing electricity demand problem following its population growth rate. The total installed capacity is far less than the current demand for electricity supply. As a way of bridging out this supply gap, the federal government is mobilizing all of its potential energy options. Coal is widely used for power generation in many countries. But today, the continued usage of coal for power generation is being challenged by the disturbing global warming phenomenon. This is due to the quantity of uncontrolled carbon dioxide emission from traditional coal-fired power plants. The aim of this dissertation is to critically analyse the future of the Nigerian coal power stations following the need to do carbon dioxide emission control necessary for ensuring a sustainable environment. Achieving this aim entails the appraisal of environmental regulation standards and cost structures of carbon dioxide (C02) emission reduction options for the coal power stations. Controlling carbon dioxide emission from existing coal power stations requires retrofit system that captures and effectively sequestrates the captured CO2. The cost and performance effect of the CO2 retrofit system on the existing power plant can be simulated with standard computer software models. In this study the lECM-cs computer modelling tool for power plants was used in determining the cost and performance impacts of applying an Amine-based C02 capture system to the Oji river power station in Nigeria. With the lECM-cs model, it was established that reducing C02 emission imposes an additional cost on the power plant which increases the unit cost of electricity generated. This additional cost index requires economic justification for its acceptance. This is due to the need to demonstrate its viability judging from the cost of electricity generated from other sources in the Nigerian economy. For the Oji river case, the station is old and requires extensive renovation. This causes a cost escalation over and above the cost associated with the CO2 sequestration system. As such, Oji coal power station does not have an economic future if C02 emission sequestration becomes obligatory. The future of coal power stations in Nigeria can be considered from two scenarios: one where the current national environmental standard is retained and another where it is revised. The revision classifies CO2 as a pollutant which makes its emission reduction imperative for coal power plants. Under the current standard, building modern large capacity pulverized coal-fired power plants with improved steam cycles should be encouraged. But with the review of the national standard, the focus should be on building new large capacity coal power stations with integrated CO2 emission control. This will ensure an environmentally friendly future for coal power stations in Nigeria. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.

Page generated in 0.1011 seconds