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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

Impacts of the Introduction of an Express Transit Service in Waterloo Region

Farahani, Samira January 2007 (has links)
For more than a century, public transportation has played a significant role in society. Transit agencies, like other service industries, are intent on improving their quality of service so as to increase transit ridership and attract passengers from other modes. In recent years transportation technologies have been improved which increase safety, mobility for people and goods, and reduce Green House Gas (GHG) emissions. An evaluation of the impacts of these operational and technological advancements is required for transit agencies to capture the potential benefits for their systems. The Region Municipality of Waterloo (RMOW), a mid-size region in Ontario has implemented an express transit service (iXpress) in Sept, 2005. The service has longer distances between stops and incorporates advanced technologies. The goal is to increase transit ridership and, as a result, to reduce GHG emissions. This research has been conducted to study the iXpress service and to develop several methods to determine the impacts of high speed transit service on passenger attraction, operational efficiency, and regional air quality. In this research, the change in total cost of travel between origin destination pairs is correlated to changes in observed ridership. Further, several surveys were conducted in the RMOW to evaluate the travel pattern changes of residents who switched from other modes to iXpress. Based on fuel consumption data, a model of GHG emissions as a function of route and vehicle characteristics has been developed to capture the operational impacts of a new iXpress service. The iXpress service of Grand River Transit (GRT) has been successful in attracting riders despite delays in technology implementation. The cost analysis presented in this research shows that the introduction of iXpress resulted in approximately 30% reduction in overall cost of travel by transit. As a result, ridership (boardings) has increased by 11% and 46% in the northern and southern sections of the iXpress service area respectively, while accounting for overall growth in the system. An analysis of travel patterns and mode shifts suggest that travelers switching from auto mode to iXpress have resulted in annualized reduction of approximately 530 tonnes of GHG. A fuel consumption analysis indicates that buses on the iXpress route have an average fuel consumption rate of 0.54 L/km while, buses serving local route consumes fuel of a rate of 0.62 L/km.
12

Analys och beräkning av emissionsfaktorer för växthusgaser / Analysis and calculations of emission factors for green house gases

Fredén, Johanna January 2010 (has links)
An increased awareness about the global warming has created a demand for more information on how the climate is affected by different activities.This master thesis was initiated by Tricorona, a Swedish company that offers its customers analysis and calculation of their climate impact. Tricorona also supplies climate neutralisation with CERs, in accordance with the Kyoto protocol and controlled by the UN. This work demands updated emission factors for greenhouse gases. An emission factor gives information about the greenhouse gasintensity of a service or a product [kg CO2-eq./ functional unit].The purpose of this thesis is to examine how electricity, district heating, hotels, taxis, food and materials affect the climate and how emission factors for these areas can be calculated.This was done by reviewing and comparing different studies and by interviewing experts. The information was evaluated and recommendations on calculations and emission factors were made.The consumption of energy is the main source of greenhouse gas emissions for district heating, electricity, hotels, taxis and materials. For food production the biogenic greenhousegas emissions are also important, such as the emissions of carbon dioxide and nitrous oxide from land use and the methane emissions from ruminants.For climate impact assessment of electricity, district heating, hotels and taxis it is recommended that the calculations should be based on an average consumption of energy. All types of energy carriers should be included in the calculations and the emission factors used should be based on Life Cycle Assessments. Climate impact assessments based on energy consumption is a simplification that underestimates the real greenhouse gas emissions. The recommended emission factors are associated with some uncertainties that originate from the quality of the data used, the assumptions made and the system boundaries that were chosen.Despite that, the recommended emission factors can be considered representative since they are based on the best available data. For food and materials it is recommended that emissionfactors from Life Cycle Inventories should be used.
13

Impacts of the Introduction of an Express Transit Service in Waterloo Region

Farahani, Samira January 2007 (has links)
For more than a century, public transportation has played a significant role in society. Transit agencies, like other service industries, are intent on improving their quality of service so as to increase transit ridership and attract passengers from other modes. In recent years transportation technologies have been improved which increase safety, mobility for people and goods, and reduce Green House Gas (GHG) emissions. An evaluation of the impacts of these operational and technological advancements is required for transit agencies to capture the potential benefits for their systems. The Region Municipality of Waterloo (RMOW), a mid-size region in Ontario has implemented an express transit service (iXpress) in Sept, 2005. The service has longer distances between stops and incorporates advanced technologies. The goal is to increase transit ridership and, as a result, to reduce GHG emissions. This research has been conducted to study the iXpress service and to develop several methods to determine the impacts of high speed transit service on passenger attraction, operational efficiency, and regional air quality. In this research, the change in total cost of travel between origin destination pairs is correlated to changes in observed ridership. Further, several surveys were conducted in the RMOW to evaluate the travel pattern changes of residents who switched from other modes to iXpress. Based on fuel consumption data, a model of GHG emissions as a function of route and vehicle characteristics has been developed to capture the operational impacts of a new iXpress service. The iXpress service of Grand River Transit (GRT) has been successful in attracting riders despite delays in technology implementation. The cost analysis presented in this research shows that the introduction of iXpress resulted in approximately 30% reduction in overall cost of travel by transit. As a result, ridership (boardings) has increased by 11% and 46% in the northern and southern sections of the iXpress service area respectively, while accounting for overall growth in the system. An analysis of travel patterns and mode shifts suggest that travelers switching from auto mode to iXpress have resulted in annualized reduction of approximately 530 tonnes of GHG. A fuel consumption analysis indicates that buses on the iXpress route have an average fuel consumption rate of 0.54 L/km while, buses serving local route consumes fuel of a rate of 0.62 L/km.
14

Analysis of Smart Grid and Demand Response Technologies for Renewable Energy Integration: Operational and Environmental Challenges

Broeer, Torsten 23 April 2015 (has links)
Electricity generation from wind power and other renewable energy sources is increasing, and their variability introduces new challenges to the existing power system, which cannot cope effectively with highly variable and distributed energy resources. The emergence of smart grid technologies in recent year has seen a paradigm shift in redefining the electrical system of the future, in which controlled response of the demand side is used to balance fluctuations and intermittencies from the generation side. This thesis investigates the impact of smart grid technologies on the integration of wind power into the power system. A smart grid power system model is developed and validated by comparison with a real-life smart grid experiment: the Olympic Peninsula Demonstration Experiment. The smart grid system model is then expanded to include 1000 houses and a generic generation mix of nuclear, hydro, coal, gas and oil based generators. The effect of super-imposing varying levels of wind penetration are then investigated in conjunction with a market model whereby suppliers and demanders bid into a Real-Time Pricing (RTP) electricity market. The results demonstrate and quantify the effectiveness of DR in mitigating the variability of renewable generation. It is also found that the degree to which Greenhouse Gas (GHG) emissions can be mitigated is highly dependent on the generation mix. A displacement of natural gas based generation during peak demand can for instance lead to an increase in GHG emissions. Of practical significance to power system operators, the simulations also demonstrate that Demand Response (DR) can reduce generator cycling and improve generator efficiency, thus potentially lowering GHG emissions while also reducing wear and tear on generating equipment. / Graduate
15

Estimating Costs of Reducing Environmental Emissions From a Dairy Farm: Multi-objective epsilon-constraint Optimization Versus Single Objective Constrained Optimization

Ebadi, Nasim 08 July 2020 (has links)
Agricultural production is an important source of environmental emissions. While water quality concerns related to animal agriculture have been studied extensively, air quality issues have become an increasing concern. Due to the transfer of nutrients between air, water, and soil, emissions to air can harm water quality. We conduct a multi-objective optimization analysis for a representative dairy farm with two different approaches: nonlinear programming (NLP) and ϵ-constraint optimization to evaluate trade-offs among reduction of multiple pollutants including nitrogen (N), phosphorus (P), greenhouse gas (GHG), and ammonia. We evaluated twenty-six different scenar- ios in which we define incremental reductions of N, P, ammonia, and GHG from five to 25% relative to a baseline scenario. The farm entails crop production, livestock production (dairy and broiler), and manure management activities. Results from NLP optimization indicate that reducing P and ammonia emissions is relatively more expen- sive than N and GHG. This result is also confirmed by the ϵ-constraint optimization. However, the latter approach provides limited evidence of trade-offs among reduction of farm pollutants and net returns, while the former approach includes different re- duction scenarios that make trade-offs more evident. Results from both approaches indicate changes in crop rotation and land retirement are the best strategies to reduce N and P emissions while cow diet changes involving less forage represents the best strategy to reduce ammonia and GHG emissions. / Master of Science / Human activities often damage and deplete the environment. For instance, nutrient pollution into air and water, which mostly comes from agricultural and industrial activ- ities, results in water quality degradation. Thus, mitigating the detrimental impacts of human activities is an important step toward environmental sustainability. Reducing environmental impacts of nutrient pollution from agriculture is a complicated problem, which needs a comprehensive understanding of types of pollution and their reduction strategies. Reduction strategies need to be both feasible and financially viable. Con- sequently, practices must be carefully selected to allow farmers to maximize their net return while reducing pollution levels to reach a satisfactory level. Thus, this paper conducts a study to evaluate the trade-offs associated with farm net return and re- ducing the most important pollutants generated by agricultural activities. The results of this study show that reducing N and GHG emissions from a representative dairy farm is less costly than reducing P and ammonia emissions, respectively. In addition, reducing one pollutant may result in reduction of other pollutants. In general, for N and P emissions reduction land retirement and varying crop rotations are the most effective strategies. However, for reducing ammonia and GHG emissions focusing on cow diet changes involving less forage is the most effective strategy.
16

A review of the energy efficiency (EE) market funding constraints and assessment of possible effective financing models for EE projects in the South African market reflecting on lessons from other markets

Marowa, Cyprian 11 November 2011 (has links)
Cannot copy abstract
17

Clean Coal And Carbon Capture And Storage Technology Roadmap Of Turkey

Vural, Asli 01 February 2010 (has links) (PDF)
The present study presents a draft national CCT (Clean Coal Technologies) and CCS (Carbon Capture and Storage) technology roadmap to policy makers. Various technical and non-technical (economic and social) challenges that currently prevent CCT and CCS from being a widely used commercial technology are discussed and the goals for each research pathway are defined. The process of creating the roadmap started with a review and assessment of the existing national and international technology roadmaps which represent a global picture of the state of the art and national and international plans for future on CCT and CCS research development, demonstration and deployment (R&amp / D&amp / D). Following this step, the national situation, capacities and priorities were examined. Finally, R&amp / D&amp / D actions discussed in the existing roadmaps and/or new actions were carefully selected and suggested as a draft Turkish CCT and CCS Roadmap that needs further development and discussion by the input of interdisciplinary national stakeholders. As a conclusion a number of technical and non-technical suggestions are delivered.
18

Le changement climatique de la simulation aux modes d'existence : étude de trajectoires climatiques de villes et d'entreprises en Alsace / Climate change from simulation to modes of existence : climatic trajectories of cities and companies in Alsace

Amat, Amandine 30 September 2016 (has links)
Cette thèse porte sur l’ultimatum qu’impose le phénomène de changement climatique à la société occidentale contemporaine : changer de modèle de société ou risquer l’effondrement (Diamonds,2006). L’épreuve majeure qui s’impose serait celle d’habiter autrement la Terre, autour d’un autre projet : celui de la lutte contre le changement climatique. De nombreuses publications (Aykut,2012 ; Dahan, 2015 ; Latour, 2015 ; Roques, 2013 ; Stengers, 2009) décrivent l’incapacité des institutions étatiques à construire un projet commun pour répondre aux enjeux climatiques. Dans cette affaire, les études « critiques » relèvent la place importante qu’a prise la simulation au détriment de l’action concrète et pérenne. Modélisations climatiques, simulations politiques et économiques, diagnostics sociologiques, fictions littéraires, le changement climatique est largement investi par le récit. Nos immersions de terrain ont montré que d’autres échelles de l’action s’emparaient déjà activement de l’affaire climatique. Villes et entreprises sont, en effet, de plus en plus nombreuses à prendre position dans la problématique énergie-climat. Il s’ensuit que certains énoncés, par leur position de médiateurs, avaient cédé la place à des expérimentations concrètes. Adoptant une démarche pragmatique, inspirée de l’Enquête sur les modes d’existence, proposée par Latour, et enrichie par le modèle des Économies de la Grandeur de Boltanski et Thévenot, cette thèse tente de décrire les divers modes d’existence de la problématique climatique auprès de collectifs territoriaux. Par ailleurs, nous faisons l’hypothèse de l’influence d’arrières plans culturels et d’intérêts passionnés dans la production de stratégies climatiques par des acteurs locaux. / This thesis focuses on the ultimatum imposed by the climate change phenomenon in contemporary Western society : changing the model of society or risk collapse (Diamonds, 2006). The major ordealt hat is required was that of otherwise inhabit the Earth around another project : the fight against climate change. Many publications (Aykut, 2012 ; Dahan, 2015 ; Latour, 2015 ; Roques, 2013 ;Stengers, 2009) describe the inability of state institutions to build a common project to respond to climate challenges. In this situation, the "critical" studies note the important place that has taken the simulation at the expense of concrete and sustainable action. Climate modelling, political and economic simulations, sociological diagnoses, literary fiction, climate change is largely invested by the narrative. Our field immersions have shown that other scales of action are already actively seized ofthe climate deal. Cities and businesses are in fact more likely to take a position in the energy and climate challenge. It follows that some statements, by their position mediators had given way to concrete experiments. Taking a pragmatic approach, inspired by the l’Enquête sur les modes d’existence proposed by Latour, and enriched by the model of Économies de la Grandeur of Boltanski and Thevenot, this thesis attempts to describe the various modes of existence of the climate problem from territorial collectives. We also assuming the rear of influence cultural plans and attachments in producing climate strategies by local actors.
19

Treibhausgas-Emissionen in der deutschen Landwirtschaft / Herkunft und technische Minderungsmaßnahmen unter besonderer Berücksichtigung von Biogas / Green house gas emissions in German agriculture / Sources and technical reduction capacities under special consideration of biogas

Wegener, Jens-Karl 25 January 2007 (has links)
No description available.
20

Allocation of GHG emissions in a paper mill, an application tool to reduce emissions

Aldrich Tomàs, Remei 30 April 2009 (has links)
El sector de pasta i paper és considerat un dels set sectors industrials més intensius en consum energètic. La producció i consum d'electricitat i de vapor esdevenen les fonts majoritàries d'emissions de gasos d'efecte hivernacle en aquest sector industrial. Les fàbriques papereres poden assolir objectius de reducció d'emissions mitjançant reducció en origen (substitució de combustibles, introducció d'energies renovables) o bé a partir de mesures d'eficiència energètica en el propi procés. En aquest context, s'ha desenvolupat un mètode de distribució d'emissions que permet assignar a cada unitat d'operació del procés paperer, el seu grau de responsabilitat en emissions. També s'han avaluat diferents mètodes de càlcul de factors d'emissió de vapor i electricitat, tant per plantes de cogeneració com per sistemes individuals. A partir d'aquesta avaluació s'han proposat nous mètodes alternatius als analitzats. Aquests mètodes i els factors d'emissions s'han aplicat a dues fàbriques papereres catalanes. / Pulp and paper sector is considered one of the seven industrial sectors with a higher energy intensive profile. Power and steam production and consumption are the main responsible for green house gas emissions of this industrial activity. Paper industries can achieve reductive emission targets by considering emissions origin (replacing fuels, aplying renewable energies) as well as improving energy efficiency of the process itself. An emission allocation tool has been developed with the purpose of approaching to each unit operation of the papermaking process its related emissions share. In addition, energy-emission factors regarding power and steam generation in combined heat and power plants and in single heat and power systems have been evaluated. Some new methods for calculating different emission factors have been proposed after the analysis. Two Catalan paper mills have been used as case-studies to apply, both allocation method and emission factors.

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