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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

Minimizing Carbon Emissions in Metal Forming

NAVA, PAOLO 22 December 2009 (has links)
The present work deals with the calculation and the investigation of possible reductions of CO2 emissions in manufacturing a metal formed product. The industrial sector plays a significant role in the recent increase of the oncentration of Greenhouse Gases in the atmosphere, which is responsible for the advancing global warming. As an answer to fiscal and financial intervention of government policies aimed at counteracting this phenomenon, the environmental impact of products became a key aspect of a company’s strategy. However, literature still lacks effective methods and quantitative studies that look into the details of a single manufacturing process, discussing its environmental aspects and how they can be influenced by changes in the technological parameters. In an attempt to do that, an example of quantification and minimization of the carbon emissions occurring during the two manufacturing steps of the fabrication of an Al 6061 disc is provided. Electrical energy consumption occurring during the shearing and the upset forging of a billet was found by means of nonlinear finite element analysis and converted into CO2 emissions with a carbon emission signature value (CES). Environmental impact and frictional properties of both traditional lubrication and two non-conventional ecologically benign lubricants (palm oil ester and used cooking oil ester) were experimentally tested and are included in the study. A gradient-based optimization algorithm was implemented to determine the optimal geometry of the billet before the compression as well as the lubricant that minimize the total carbon emissions, within the proper technological limitations and constraints on the final product quality. A clear and effective method which would represent an auxiliary decision tool for a manufacturer in the metal forming sector is hereby presented. Results show that the selection of the manufacturing options can have an influence of more than 13% on the overall CO2 emission. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-12-19 16:39:12.071
2

Accounting for carbon in the FTSE100 : numbers, narratives and credibility

Malamatenios, John January 2015 (has links)
The United Kingdom Government has mandated ambitious carbon objectives, requiring an 80% reduction in emissions by 2050, and a 20% interim reduction by 2020. Their achievement will require government and large companies to work together, and for each to be assured of the other’s strategic intent. An emergent carbon accounting can provide reassurance if it produces credible information that supports the claims made by each party. This thesis investigates the extent to which carbon reduction narratives are supported or contradicted by actual carbon emissions disclosed in corporate accounting reports. It also investigates whether large corporations have delivered absolute carbon reductions in support of the government’s legally binding objectives. As a result of these and other investigations, the thesis contributes to the carbon accounting literature by critiquing the method of framing emissions employed by the Greenhouse Gas Protocol, the extent to which carbon reduction is supported by meaningful managerial incentives and the means by which analysts might rebalance financial return with carbon risk in portfolio construction. Following a middle ground approach, the research employs a numbers and narratives analysis in which critical alternative narratives are created at national, sectoral and firm levels. The analysis disaggregates macro carbon emissions data, and considers carbon emissions at a corporate meso and micro level. Narratives constituted out of these numbers, together with counter-narratives generated from corporate disclosures, are then evaluated to assess their credibility. The thesis adopts a practical approach, utilising multiple framing devices. In addition to reporting scopes 1, 2 and 3 carbon emissions, it describes a business model framework in which firms are expected to disclose their carbon-material stakeholder relations. Further recommendations are aimed at aligning the interests of corporate managers, investors and financial analysts with government carbon policy in order to modify behaviour and reduce emissions trajectories towards a lower carbon future.
3

Benchmarking the energy use of historic dwellings in Bath and the role for retrofit and LZC technologies to reduce CO2 emissions

Moran, Francis January 2013 (has links)
Historic dwellings in the UK make up 20% of all homes and are amongst the most poorly performing part of the English housing stock in energy use terms, with the lowest SAP rating and highest average annual CO2 emissions. The degree to which proposals to retrofit the UK housing stock can reduce emissions depends on current energy use and CO2 emissions. Current methodology relies on national aggregated statistics to provide average energy use data; historic buildings as a subset cannot be segregated. In order to assess realistic carbon reduction potential it is vital that performance of historic dwellings is established from disaggregated data sources or with validated and stakeholder accepted models that can accurately prescribe energy use in an affordable, easy to use and transparent manner. This research attempts to begin such orthodoxy. The benchmark derived in this study suggests that historic buildings in Bath use less energy than predicted by national, regional, and local average energy use, but they are not low energy dwellings. They therefore require retrofit adaptations to reduce CO2 emissions. Procedures to assess the potential for such measures are of primary importance as some adaptations impact on both fabric and aesthetics. It is therefore imperative that the contribution such alterations make towards reducing CO2 emissions can be weighed against the change they may make to our built heritage. Using the Passive House Planning Package modelling tool, predictions of energy use were provided and validated against actual energy use. The model demonstrated accuracy in predicting energy used when incorporating a reduction factor to reflect intermittent heating patterns. The model was then used to assess the retrofit adaptation measures with a suite of measures incorporating renewable energy technology, delivering CO2 emission reductions approaching 80%. This approach can be applied beyond the UK as the model permits the use of local weather data sets. In establishing a benchmark of energy use in domestic historic dwellings, this work assists in developing suitable and effective solutions that are replicable and durable, permitting built heritage to meet UK emissions targets through the provision of empirical data to evaluate any alteration to fabric or aesthetics against the benefit of carbon savings.
4

Modeling Returns on Carbon Emission Allowances: An Application to RGGI

Keneally, James 01 January 2019 (has links)
This thesis attempts to model the returns on Regional Greenhouse Gas Initiative (RGGI) allowances using logged monthly returns from 2011-2018. This asset, shown to be a useful diversifier in portfolios, has been identified by previous literature to behave similarly to commodities. I used auto-regressive, GARCH, and Markov regime switching models to analyze the returns because the returns displayed changing volatility. These models were comparatively analyzed both in and out-of-sample. In this limited data analysis, the Markov model outperformed both alternatives in-sample. The Markov and Garch models displayed similar predictive power out-of-sample, however neither were particularly effective.
5

Grönt resande : En studie om hur företag arbetar med klimatkompensation

Karadag, Yeliz, Rickman, Marita January 2010 (has links)
Carbon offsetting means to offset those greenhouse gases that are caused by our actions. The purpose of this paper is to examine how companies are working with carbon offsetting. The focus of the research is how travel agencies and companies that provides carbon offsetting. The writers also highlight the problems carbon offsetting is facing. The study was performed with qualitative methods through interviews with three companies working with carbon offsetting. The research shows that carbon offsetting within air travel can vary in price between different companies and they find it more lucrative to work with business customers. The writers have come to the conclusion that it is people's attitudes as well as lack of promotion and information that is the problem that exists for carbon offsetting. The writers have also found out that it is the uncertainty about carbon offsetting that affects the individual's attitude towards the subject. This, as well as the awareness that exists about the subject and the economy which every individual is prepared to spend on the environment.
6

Economics of biomass fuels for electricity production: a case study with crop residues

Maung, Thein Aye 15 May 2009 (has links)
In the United Sates and around the world, electric power plants are among the biggest sources of greenhouse gas emissions which the Intergovernmental Panel on Climate Change argued was the main cause of climate change and global warming. This dissertation explores the factors which may induce electricity producers to use biomass fuels for power generation and thereby mitigate the impact of greenhouse gas emissions. Analyses in this dissertation suggest that there are two important factors which will play a major role in determining the future degree of bioelectricity production: the price of coal and the future price of carbon emissions. Using The Forest and Agricultural Sector Optimization Model—Green House Gas version (FASOMGHG) in a case study examining the competitiveness of crop residues, this dissertation finds that crop residues currently cost much more than coal as an electricity generation feedstock because they have lower heat content and higher production /hauling costs. For them to become cost competitive with coal, the combined costs of production and hauling must be cut by more than half or the coal price needs to rise. In particular, for crop residues to have any role in electricity generation either the price of coal has to increase to about $43 per ton or the carbon equivalent price must rise to about $15 per ton. The simulation results also show that crop residues with higher heat content such as wheat residues will have greater opportunities in bioelectricity production than the residues with lower heat content. In addition, the analysis shows that improvements in crop yield do not have much impact on bioelectricity production. However, the energy recovery efficiency does have significant positive impact on the bioelectricity desirability but again only if the carbon equivalent price rises substantially. The analysis also shows the desirability of cofiring biomass as opposed to 100% replacement because this reduces haling costs and increases the efficiency of heat recovery. In terms of policy implications, imposing carbon emission restrictions could be an important step in inducing electric power producers to include biofuels in their fuelmix power generation portfolios and achieve significant greenhouse gas emission reductions.
7

The potential impact of carbon emissions tax on the South African mining industry / Lambertus Huisman

Huisman, Lambertus January 2014 (has links)
The objective of this research and aim of this dissertation was to determine the potential impact of the introduction of a carbon emissions tax (hereafter CET) on the South African mining industry and this has been achieved by addressing the following three areas of research: Most urgently, a literature review was required in order to obtain an understanding of why a carbon tax or alternative system was required. A detailed understanding of the functioning of these systems was invaluable to the outcome of the study. The survey conducted, confirmed the fact that global warming and related climate change brought about by human interference, constitute both global and national complications. The study confirmed that market based instruments can assist in addressing this problem and that these are generally considered to be more effective than traditional command-and-control policies. Notwithstanding this finding, in order to ensure efficacy, careful consideration should be given to the economic climate in which they are to be implemented. Secondly, a literature review was essential in order to fully comprehend the nature of the South African economy and specifically the South African mining industry’s contribution to the aforementioned problem. The importance of the industry to the economy had to be acknowledged. It was then established that the South African economy, and in particular the South African mining industry, contribute to this predicament due to their considerable dependence on coal fired power stations for the supply of electricity. The study revealed that should this industry be adversely affected by the proposed taxation, the economy as a whole would suffer. Finally, a literature review as well as quantitative examples were used to estimate the impact of CET on the South African mining industry. This outcome was achieved by evaluating the results of taxation as opposed to the objectives of the Mineral and Petroleum Resources Development Act 28 of 2002 (MPRDA). The study found that the effect on most of the objectives of the MPRDA, and especially those related to job creation, economic growth and equal access for all applicants on entering the arena of the mining industry, may well be affected adversely by the implementation of the proposed CET, as the tax was found to impact negatively on the industry’s profits. It has also been assessed that the iron ore sector will be the most affected sector and that smaller companies will be affected to a larger degree than larger companies. The modus operandi and selection of allocated beneficiaries when allocating the revenue collected from the proposed CET by the National Treasury were also found to play a significant role in whether or not the objectives of the MPRDA were positively or negatively influenced by the implementation of the tax. The outcome of the study performed on the research question confirmed that, if said effect of the proposed CET on the South African mining industry was to be compared to the objective of the MPRDA, both positive and negative implications could be identified. / MCom (South African and International Taxation), North-West University, Potchefstroom Campus, 2014
8

The potential impact of carbon emissions tax on the South African mining industry / Lambertus Huisman

Huisman, Lambertus January 2014 (has links)
The objective of this research and aim of this dissertation was to determine the potential impact of the introduction of a carbon emissions tax (hereafter CET) on the South African mining industry and this has been achieved by addressing the following three areas of research: Most urgently, a literature review was required in order to obtain an understanding of why a carbon tax or alternative system was required. A detailed understanding of the functioning of these systems was invaluable to the outcome of the study. The survey conducted, confirmed the fact that global warming and related climate change brought about by human interference, constitute both global and national complications. The study confirmed that market based instruments can assist in addressing this problem and that these are generally considered to be more effective than traditional command-and-control policies. Notwithstanding this finding, in order to ensure efficacy, careful consideration should be given to the economic climate in which they are to be implemented. Secondly, a literature review was essential in order to fully comprehend the nature of the South African economy and specifically the South African mining industry’s contribution to the aforementioned problem. The importance of the industry to the economy had to be acknowledged. It was then established that the South African economy, and in particular the South African mining industry, contribute to this predicament due to their considerable dependence on coal fired power stations for the supply of electricity. The study revealed that should this industry be adversely affected by the proposed taxation, the economy as a whole would suffer. Finally, a literature review as well as quantitative examples were used to estimate the impact of CET on the South African mining industry. This outcome was achieved by evaluating the results of taxation as opposed to the objectives of the Mineral and Petroleum Resources Development Act 28 of 2002 (MPRDA). The study found that the effect on most of the objectives of the MPRDA, and especially those related to job creation, economic growth and equal access for all applicants on entering the arena of the mining industry, may well be affected adversely by the implementation of the proposed CET, as the tax was found to impact negatively on the industry’s profits. It has also been assessed that the iron ore sector will be the most affected sector and that smaller companies will be affected to a larger degree than larger companies. The modus operandi and selection of allocated beneficiaries when allocating the revenue collected from the proposed CET by the National Treasury were also found to play a significant role in whether or not the objectives of the MPRDA were positively or negatively influenced by the implementation of the tax. The outcome of the study performed on the research question confirmed that, if said effect of the proposed CET on the South African mining industry was to be compared to the objective of the MPRDA, both positive and negative implications could be identified. / MCom (South African and International Taxation), North-West University, Potchefstroom Campus, 2014
9

Capacity Investment in Renewable and Conventional Energy Sources

Yucel, Safak January 2016 (has links)
<p>This dissertation studies capacity investments in energy sources, with a focus on renewable technologies, such as solar and wind energy. We develop analytical models to provide insights for policymakers and use real data from the state of Texas to corroborate our findings. </p><p>We first take a strategic perspective and focus on electricity pricing policies. Specifically, we investigate the capacity investments of a utility firm in renewable and conventional energy sources under flat and peak pricing policies. We consider generation patterns and intermittency of solar and wind energy in relation to the electricity demand throughout a day. We find that flat pricing leads to a higher investment level for solar energy and it can still lead to more investments in wind energy if considerable amount of wind energy is generated throughout the day.</p><p>In the second essay, we complement the first one by focusing on the problem of matching supply with demand in every operating period (e.g., every five minutes) from the perspective of a utility firm. We study the interaction between renewable and conventional sources with different levels of operational flexibility, i.e., the possibility</p><p>of quickly ramping energy output up or down. We show that operational flexibility determines these interactions: renewable and inflexible sources (e.g., nuclear energy) are substitutes, whereas renewable and flexible sources (e.g., natural gas) are complements. </p><p>In the final essay, rather than the capacity investments of the utility firms, we focus on the capacity investments of households in rooftop solar panels. We investigate whether or not these investments may cause a utility death spiral effect, which is a vicious circle of increased solar adoption and higher electricity prices. We observe that the current rate-of-return regulation may lead to a death spiral for utility firms. We show that one way to reverse the spiral effect is to allow the utility firms to maximize their profits by determining electricity prices.</p> / Dissertation
10

Policies to Reduce CO2 Emissions: Fallacies and Evidence from the United States and California

Granados, José A. Tapia, Spash, Clive L. January 2019 (has links) (PDF)
Since the 1990s, advocates of policy to prevent catastrophic climate change have been divided over the appropriate economic instruments to curb CO2 emissions-carbon taxes or schemes of emission trading. Barack Obama claimed that policies implemented during his presidency set in motion irreversible trends toward a clean-energy economy, with the years 2008-2015 given as evidence of decoupling between CO2 emissions and economic growth. This is despite California being the only state in the USA that has implemented a specific policy to curb emissions, a cap-and-trade scheme in place since 2013. To assess Obama's claims and the effectiveness of policies to reduce CO2 emissions, we analyze national and state-level data from the USA over the period 1990-2015. We find: (a) annual changes in emissions strongly correlated with the growth conditions of the economy; (b) no evidence for decoupling; and (c) a trajectory of CO2 emissions in California which does not at all support the claim that the cap-and-trade system implemented there has reduced CO2 emissions. / Series: SRE - Discussion Papers

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