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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

All CO2 molecules are equal, but some CO2 molecules are more equal than others

Grönkvist, Stefan January 2005 (has links)
This thesis deals with some challenges related to the mitigation of climate change and the overall aim is to present and assess different possibilities for the mitigation of climate change by: • Suggesting some measures with a potential to abate net greenhouse gas (GHG) emissions, • Discussing ideas for how decision-makers could tackle some of the encountered obstacles linked to these measures, and • Pointing at some problems with the current Kyoto framework and suggesting modifications of it. The quantification of the net CO2 effect from a specific project, frequently referred to as emissions accounting, is an important tool to evaluate projects and strategies for mitigating climate change. This thesis discusses different emissions accounting methods. It is concluded that no single method ought to be used for generalisation purposes, as many factors may affect the real outcome for different projects. The estimated outcome is extremely dependent on the method chosen and, thus, the suggested approach is to apply a broader perspective than the use of a particular method for strategic decisions. The risk of losing the integrity of the Kyoto Protocol when over-simplified emissions accounting methods are applied for the quantification of emission credits that can be obtained by a country with binding emissions targets for projects executed in a country without binding emission targets is also discussed. Driving forces and obstacles with regard to energy-related co-operations between industries and district heating companies have been studied since they may potentially reduce net GHG emissions. The main conclusion is that favourable techno-economic circumstances are not sufficient for the implementation of a co-operation; other factors like people with the true ambition to co-operate are also necessary. How oxy-fuel combustion for CO2 capture and storage (CCS) purposes may be much more efficiently utilised together with some industrial processes than with power production processes is also discussed. As cost efficiency is relevant for the Kyoto framework, this thesis suggests that CCS performed on CO2 from biomass should be allowed to play on a level playing field with CCS from fossil sources, as the outcome for the atmosphere is independent of the origin of the CO2. / QC 20101015
12

Residential Sector Energy and GHG Emissions Model for the Assessment of New Technologies

Swan, Lukas G. 05 August 2010 (has links)
Worldwide, the residential sector is a major consumer of energy. Both the rate at which we consume energy and our use of non-renewable energy resources have come under pressure to change. These changes may occur to some extent by conservation techniques. However, due to living standard expectations, these changes will primarily rely on technology. Many technological opportunities exist to reduce the conventional energy consumption and greenhouse gas (GHG) emissions of the residential sector, such as: improving energy efficiency, introducing alternative energy conversion technologies, and increasing the use of renewable energy resources. The accurate estimate of the impact that a new technology has on residential sector energy consumption and GHG emissions requires a versatile, reliable, detailed, and high-resolution analytical model. Such models account for the wide range of climate, energy supply, and housing stock characteristics, and are useful for decision makers to evaluate and parametrically compare a wide range of energy efficiency measures and technology strategies when applied to the residential sector. This dissertation presents the development of a new energy consumption and GHG emissions model of the Canadian residential sector. This new model is detailed with regard to the housing stock, comprehensive with regard to the treatment of end-uses (including thermodynamic behaviour and occupant behaviour), and possesses the capability, resolution, and accuracy to assess the impact upon energy consumption and GHG emissions due to the application of alternative and renewable energy technologies to the residential sector. The new model is titled the Canadian Hybrid Residential End-Use Energy and GHG Emissions Model (CHREM). The CHREM advances the state-of-the-art of residential sector energy consumption and GHG emissions modeling by three principal contributions: i) a database of 16,952 unique house descriptions of thermal envelope and energy conversion system information that statistically represent the Canadian housing stock; ii) a “hybrid” modeling approach that integrates the bottom-up statistical and engineering modeling methods to account for occupant behaviour, and provide the capacity to model alternative and renewable energy technologies, such as solar energy and energy storage systems; and iii) a method for the accumulation and treatment of energy and GHG emissions results.
13

Life Cycle Assessment of Biomass Conversion Pathways

Kabir, Md R Unknown Date
No description available.
14

Meta-analysis of GHG mitigation potentials of the application of anaerobic digestion in dairy farms

Miranda, Nicole January 2016 (has links)
Dairy farms can apply anaerobic digestion (AD) as a manure management system, while producing renewable energy. Ultimately, this can reduce greenhouse gas (GHG) emissions. There is much research work that has quantified the changes in emissions due to AD. However, important methodologies such as the Intergovernmental Panel on Climate Change (IPCC) Guidelines, rely only on a small sample of the accumulated scientific findings in the field. This thesis improves the robustness of these methodologies by applying data-driven techniques to estimate values of the energy output of AD systems and their consequent effect in GHG emissions. For this purpose, meta-analyses techniques are applied to mathematically combine metrics from 155 non-standardised research publications (i.e. with different boundaries, scopes and functional units). As a first step, a novel database is created by systematically searching for relevant articles and assessing them against defined criteria. The database is divided in two parts. Given that the offset of GHGs is highly dependent on the energy output of AD system, empirical methane yields (i.e. key metric of AD performance) are collected in Part I of the database. GHG released from different farm activities are input to Part II of the database. To quantify the change in emissions from these activities, standard baseline and AD scenarios are defined. The second step of the meta-analysis consists of applying uni- and multi-variate tests to the database. For Part I, methane yields are analysed in terms of type of digesters. From the batch digesters, new maximum methane yields are proposed based on the combined results of 42 peer reviewed articles. These results offer better estimates than default values of methane yields from the 2007 Guidelines of the IPCC, which only consider two studies. For continuously stirred tank digesters and semi-continuous digesters lower methane yields are revealed. Multi-variate analysis of methane yields together with operating conditions and manure composition, enable the identification of clusters. These groups of variables can be useful to build potential AD scenarios in dairy farms. For Part II of the database, relative changes in emissions between the activities in the standardised baseline and AD scenarios, are examined. It is found, through meta-analysis, that replacing raw manure by anaerobically-treated manure (i.e. digestate) in storage tanks and for field- application, mitigates baseline emissions by 38.7% and 6.9%, respectively. These relative changes can be used to estimate emissions from digestate, being more specific and evidence-based than the current methodology from the IPCC. In addition, relative changes found for offset of fossil fuels by biogas generated in the AD scenarios indicate a reduction of baseline emissions by 9.0%. Only methane leaks from digesters significantly increase the baseline emissions (by 7.4%). Finally, results found by meta-analyses of methane yields and changes in emissions are applied to four dairy farm case studies. The work presented in the case studies demonstrates the benefits of enhancing the robustness of methods to estimate the effect of AD on GHG emissions from dairy farms.
15

Forest Carbon Dynamic – Positive and Negative perspectives on the use of Biomass Energy to replace Fossil Fuel

Lundmark, Kennia January 2018 (has links)
From 1970 to 2010, circa 78% of the Greenhouse gases emissions came from the emissions of CO2 derived from industrial processes and fossil fuel combustion. The fossil energy resources (coal, oil and natural gas) increase the concentration of carbon dioxide in the atmosphere causing diverse changes related to global warming. Despite policies adopted to mitigate the climate change, global warming is not decreased. This literature review will analyze and investigate the use of forest biomass to replace fossil fuel energy and how it can affect climate change. This study used secondary data to identify the main perspectives in the use of forest biomass to produce energy. The policies at the global, regional and national level are also described. How the national level is influenced by the international and regional level and how the policies match with the current knowledge on the theme. The results showed that the use of forest biomass was better to replace coal than natural gas or oil, due to the payback time. The use of old-growth forests or natural forest increases the time to the released emissions to be offset. Residues showed to have faster payback time than other forest biomass, as well as, the use of this biomass avoid cut down trees. However, the use of residues can cause serious impacts, as biodiversity loss. The conclusion was that the use of biomass will increase the CO2 emissions, whether all emissions are included. Despite the payback time is faster to forest biomass than fossil fuel, biomass is not a good alternative to replace fossil fuel energy. Because of the combustion efficiency of biomass is less than fossil fuel to produce the same amount the energy. Regarding the policies, there are contradictions between the international and regional level about the use of forests. As also, regional level has contradictions in their criteria that should be avoided. If the forest biomass has to be use, this study recommended the use of residues. / <p>20180619</p>
16

A pegada ecológica dos incidentes rodoviários / Ecological footprint of road incidents

Dexheimer, Leticia January 2012 (has links)
Este estudo tem por finalidade modelar a pegada ecológica de incidentes rodoviários que interrompem o fluxo normal de circulação. A pegada ecológica é um indicador que mede o impacto das atividades humanas em quantidades de áreas de terra, água e energia utilizadas para sustentar uma população de determinada região. Em transportes, esse impacto é medido pela área hipotética que deveria ser reservada para a absorção do CO2 emitido que tem constituído, nos últimos anos, a fatia mais significativa das pegadas ecológicas na maioria dos países. A vantagem de utilizar essa abordagem reside na facilidade de entendimento, na simplicidade e na utilização de uma unidade única de comparação entre emissões de diferentes setores. O método proposto e aplicado neste trabalho proporciona a identificação dos impactos dos incidentes, particularmente acidentes viários e obras de manutenção viária, em termos de pegada ecológica. O estudo de caso constou de uma rodovia de pista simples cujas emissões foram avaliadas com a utilização de simulação de tráfego. Como resultado obteve-se uma pegada ecológica de cerca de 2.180 hectares decorrente dos incidentes ao longo de um ano de operação da via. Este valor corresponde a 4% da pegada ecológica da via em condições normais de operação. Ainda, os resultados indicam que os incidentes com maior impacto sobre o meio ambiente são as obras para a manutenção da rodovia que contribuem com 60% do total gerado pelos incidentes. / The purpose of this study is to model the ecological footprint of road incidents that interrupt the normal flow of vehicles. The ecological footprint is an accounting framework that measures the impact of human activities considering amounts of land, water and energy areas used to sustain the population of a region. In transportation, this impact is measured by the hypothetical area required to absorb CO2 emissions from burning fossil fuels that has been responsible, over the last years, for the largest share of the ecological footprint of nations. The advantage of using this approach is the ease of understanding, simplicity and the use of a single unit for comparing emissions from different sectors. The method proposed and deployed in this work enables identifying the impact of incidents, basically road accidents and maintenance works, on the transportation ecological footprint. The case study was composed of a single lane highway whose emissions were evaluated with the use of traffic simulation. We obtained an ecological footprint of 2,180 ha due to road incidents over a period of one year. This corresponds to 4% of the ecological footprint of normal road operations. Results also indicate that the incidents with the greatest impact on the environment are the works for the maintenance of the highway which contribute with 60% of the total value.
17

Essays on Environmental Spillovers in Supply Chains

January 2018 (has links)
abstract: The phenomenon of global warming and climate change has increasingly attracted attention by researchers in the field of supply chain and operations management. Firms have developed efficient plans and intervention measures to reduce greenhouse gas (GHG) emissions. While a majority of research in supply chain management has adopted a firm-centric view to study environmental management, this dissertation focuses on the context of GHG emissions reduction by considering a firm’s vertical and horizontal relationships with other parties, and the associated spillover effects. A theoretical framework is first proposed to facilitate the field's understanding of the possible spillover effects in GHG emissions reduction via vertical and horizontal interactions. Two empirical studies are then presented to test the spillover effect in GHG emissions reduction, focusing on the vertical interactions - when firms interact with their supply chain members. Drawing data from Bloomberg Environmental Social and Governance, and Bloomberg SPLC, this study conducts econometric analyses using various models. The results suggest that first, a higher level of supply chain GHG emissions is associated with the adoption of emissions reduction programs by a firm, and that this supply chain leakage contributes to the firm’s financial performance. Second, a firm's supply base innovativeness can contribute to its internal GHG emissions reduction, and this effect is contingent on a firm's supply base structure. As such, this dissertation answers the recent call in the field of supply chain and operations management for more empirical research in socially and environmentally responsible value chains. Further, this study contributes to the literature by providing a better understanding of the externalities that value chain members can impose on one another when pursuing sustainability goals. / Dissertation/Thesis / Doctoral Dissertation Business Administration 2018
18

A pegada ecológica dos incidentes rodoviários / Ecological footprint of road incidents

Dexheimer, Leticia January 2012 (has links)
Este estudo tem por finalidade modelar a pegada ecológica de incidentes rodoviários que interrompem o fluxo normal de circulação. A pegada ecológica é um indicador que mede o impacto das atividades humanas em quantidades de áreas de terra, água e energia utilizadas para sustentar uma população de determinada região. Em transportes, esse impacto é medido pela área hipotética que deveria ser reservada para a absorção do CO2 emitido que tem constituído, nos últimos anos, a fatia mais significativa das pegadas ecológicas na maioria dos países. A vantagem de utilizar essa abordagem reside na facilidade de entendimento, na simplicidade e na utilização de uma unidade única de comparação entre emissões de diferentes setores. O método proposto e aplicado neste trabalho proporciona a identificação dos impactos dos incidentes, particularmente acidentes viários e obras de manutenção viária, em termos de pegada ecológica. O estudo de caso constou de uma rodovia de pista simples cujas emissões foram avaliadas com a utilização de simulação de tráfego. Como resultado obteve-se uma pegada ecológica de cerca de 2.180 hectares decorrente dos incidentes ao longo de um ano de operação da via. Este valor corresponde a 4% da pegada ecológica da via em condições normais de operação. Ainda, os resultados indicam que os incidentes com maior impacto sobre o meio ambiente são as obras para a manutenção da rodovia que contribuem com 60% do total gerado pelos incidentes. / The purpose of this study is to model the ecological footprint of road incidents that interrupt the normal flow of vehicles. The ecological footprint is an accounting framework that measures the impact of human activities considering amounts of land, water and energy areas used to sustain the population of a region. In transportation, this impact is measured by the hypothetical area required to absorb CO2 emissions from burning fossil fuels that has been responsible, over the last years, for the largest share of the ecological footprint of nations. The advantage of using this approach is the ease of understanding, simplicity and the use of a single unit for comparing emissions from different sectors. The method proposed and deployed in this work enables identifying the impact of incidents, basically road accidents and maintenance works, on the transportation ecological footprint. The case study was composed of a single lane highway whose emissions were evaluated with the use of traffic simulation. We obtained an ecological footprint of 2,180 ha due to road incidents over a period of one year. This corresponds to 4% of the ecological footprint of normal road operations. Results also indicate that the incidents with the greatest impact on the environment are the works for the maintenance of the highway which contribute with 60% of the total value.
19

A pegada ecológica dos incidentes rodoviários / Ecological footprint of road incidents

Dexheimer, Leticia January 2012 (has links)
Este estudo tem por finalidade modelar a pegada ecológica de incidentes rodoviários que interrompem o fluxo normal de circulação. A pegada ecológica é um indicador que mede o impacto das atividades humanas em quantidades de áreas de terra, água e energia utilizadas para sustentar uma população de determinada região. Em transportes, esse impacto é medido pela área hipotética que deveria ser reservada para a absorção do CO2 emitido que tem constituído, nos últimos anos, a fatia mais significativa das pegadas ecológicas na maioria dos países. A vantagem de utilizar essa abordagem reside na facilidade de entendimento, na simplicidade e na utilização de uma unidade única de comparação entre emissões de diferentes setores. O método proposto e aplicado neste trabalho proporciona a identificação dos impactos dos incidentes, particularmente acidentes viários e obras de manutenção viária, em termos de pegada ecológica. O estudo de caso constou de uma rodovia de pista simples cujas emissões foram avaliadas com a utilização de simulação de tráfego. Como resultado obteve-se uma pegada ecológica de cerca de 2.180 hectares decorrente dos incidentes ao longo de um ano de operação da via. Este valor corresponde a 4% da pegada ecológica da via em condições normais de operação. Ainda, os resultados indicam que os incidentes com maior impacto sobre o meio ambiente são as obras para a manutenção da rodovia que contribuem com 60% do total gerado pelos incidentes. / The purpose of this study is to model the ecological footprint of road incidents that interrupt the normal flow of vehicles. The ecological footprint is an accounting framework that measures the impact of human activities considering amounts of land, water and energy areas used to sustain the population of a region. In transportation, this impact is measured by the hypothetical area required to absorb CO2 emissions from burning fossil fuels that has been responsible, over the last years, for the largest share of the ecological footprint of nations. The advantage of using this approach is the ease of understanding, simplicity and the use of a single unit for comparing emissions from different sectors. The method proposed and deployed in this work enables identifying the impact of incidents, basically road accidents and maintenance works, on the transportation ecological footprint. The case study was composed of a single lane highway whose emissions were evaluated with the use of traffic simulation. We obtained an ecological footprint of 2,180 ha due to road incidents over a period of one year. This corresponds to 4% of the ecological footprint of normal road operations. Results also indicate that the incidents with the greatest impact on the environment are the works for the maintenance of the highway which contribute with 60% of the total value.
20

Carbon Labeling : A quantitative study of what the preferred content, design and layout is among Swedish consumers / Carbon Labeling : A quantitative study of what the preferred content, design and layout is among Swedish consumers

Sundberg, Eric, Elghag, Edvin January 2020 (has links)
Global warming has been a topic of discussion since the discovery that man-made greenhouse gas emissions is having an affect on the planet almost 50 years ago. Grocery products stand for roughly one third of all EUs carbon emissions as a result of its highvolume production. Carbon labeling is a tool in which retailers and manufacturers can communicate the amount has caused throughout its whole life cycle or that the they are working towards lowering their GHG emission throughout their organization. However, previous research indicates that carbon labels has not yet had its breakthrough moment yet due to the CO2e data is too complex for the consumers to interpret. This led to our research question “What is the preferred content, design and layout of a carbon label among Swedish consumers? “The purpose of this study is to get a deeper understanding into the preferences of the Swedish consumers and what kind of attributes they are looking for to make a carbon label understandable. We found that the Swedish consumer prefers a more complex design than previous studies have suggested based on researches made from other countries. In order to do our explanatory research, we measured these variables with a quantitative survey and made statistical calculations such as mean values and correlation analysis to see if our hypotheses were supported.  The analysis shows that the Swedish consumers prefer all the following attributes that is being presented in an order of priority: The label should be colour coded, made by a well-known organization, presented in terms of scale and have the CO2e data presented on the label.

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