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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.
21

Environmental and techno-economic analysis of ground source heat pump systems

Hanova, Jana 11 1900 (has links)
Climate change stabilization requires an unprecedented effort to change our current approach to energy production and consumption. While rising energy prices are drawing increased attention to reducing energy demand, heightened concern about the environmental consequences of fuel choice requires that this demand be met at lower emission levels. In Canada, the realization of commitments to our GHG emission goals entails reducing residential energy use - a sector responsible for close to 20 percent of end-use energy consumption. This study focuses on the energy demand and emission levels of space and water heating, since these two components comprise 76 percent of residential energy demand. Ground source heat pumps (GSHPs) are a technology that provides heating at 25 to 30 percent of the energy consumed by even the most efficient conventional alternatives. GSHPs have been identified as the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available. However, their drawbacks have been high capital costs, and uncertainty about whether the electric power used by heat pumps has higher system-wide emissions. This thesis delineates how adoption of GSHPs in the residential sector can help align Canada’s technology choices with commitments made to the Kyoto Protocol. The manuscripts delineate conditions under which GSHP systems achieve the largest net emission reductions relative natural gas, heating oil, and electric heat counterparts. Electricity generation methods and emissions embodied in inter-provincial and international electricity trade are shown to significantly affect the emission savings achievable through GSHP. The thesis quantifies how relative fuel prices influence annual operating savings that determine how rapidly the technology can achieve payback. This analysis reveals GSHPs to hold significant potential for substantial GHG reductions at a cost savings relative to conventional alternatives; the time horizons for payback are as short as nine years for average-sized homes, and significantly shorter for larger homes.
22

Techno-economic assessment of solar technologies and integration strategies for the Canadian housing stock

Nikoofard, Sara 29 August 2012 (has links)
Energy security is probably one of the most challenging issues around the world. Therefore, the focus on methods of decreasing energy consumption and consequently its associated greenhouse gas (GHG) emissions is intensified by policy decision makers. Residential buildings are one of the potential sectors that can reduce its energy consumption in various ways, such as: improving thermal characteristics of the building, using more energy efficient appliances and using renewable energy resources. Among these methods, integration of solar technologies to buildings provides one of the substantial opportunities for reducing energy consumption and the associated GHG emissions in Canada’s residential sector. Therefore, this research work was conducted to assess the impact of solar technologies and solar technology integration strategies on the end-use energy consumption and the associated greenhouse gas (GHG) emissions in Canadian residential sector by using a new state-of-the-art end-use energy and GHG emissions model of the Canadian residential housing stock. The new Canadian residential end-use energy and emissions model that is used in this project incorporates a 17,000 house database developed using the latest data available from the Energuide for Houses database, Statistics Canada housing surveys, and other available housing databases, and utilizes an advanced building energy simulation program as its simulation engine. A new neural network methodology is incorporated into the model to estimate the socio-economic and demographic dependencies of the energy consumption of discretionary end-uses such as appliances, lighting and domestic hot water, while a new approach is used to incorporate occupancy, appliance, lighting and domestic hot water load profiles into the model. A new method is used to calculate the GHG emissions from electricity consumption used in the residential sector based on the actual electrical generation fuel mix and the marginal fuel used in each province as a function of time of the year. Each solar technology is added to the eligible houses to examine the interrelated effects of integrated solar technologies and practices on the housing stock. The objective is to conduct realistic assessments of the cost effectiveness, energy savings and GHG emission reduction benefits of integrated solar technologies for the entire Canadian housing stock (CHS) as well as for different regions, house type, and fuel types. The integrated solar technologies and practices that are assessed include passive solar with added thermal storage and motorized blinds, solar DHW system, and photovoltaic electricity and heat generation systems. This project provides a comprehensive techno-economic and emissions assessment of integrated solar technologies and practices, and will be useful for developing national and regional policies and strategies related with integrating solar energy into the residential sector.
23

Comparison of Simultaneous Soil Profile N2O Concentration and Surface N2O Flux Measurements Overwinter and at Spring Thaw in an Agricultural Soil

Risk, Neil 28 May 2012 (has links)
A field experiment was carried out in Ontario, Canada to compare independently measured soil N2O profile concentration and surface N2O flux measurements overwinter and at spring thaw, to estimate the soil N2O content accumulation overwinter, and to estimate the magnitude of the contribution of the physical release of trapped N2O to surface fluxes at spring thaw. Gas samples at various depths were taken and N2O concentrations determined, soil profile gaseous N2O content was calculated by estimating the air-filled pore-space from soil condition measurements, and soil aqueous N2O content was calculated using liquid water content measurements and applying Henry’s Law. Soil N2O content was found to reach a maximum of ~25 mg N2O m-2, and by comparing changes in soil N2O content to surface fluxes measured using the micrometeorological flux-gradient technique, the physical release of previously produced N2O was estimated to contribute up to 47% of spring thaw N2O surface fluxes.
24

Environmental and techno-economic analysis of ground source heat pump systems

Hanova, Jana 11 1900 (has links)
Climate change stabilization requires an unprecedented effort to change our current approach to energy production and consumption. While rising energy prices are drawing increased attention to reducing energy demand, heightened concern about the environmental consequences of fuel choice requires that this demand be met at lower emission levels. In Canada, the realization of commitments to our GHG emission goals entails reducing residential energy use - a sector responsible for close to 20 percent of end-use energy consumption. This study focuses on the energy demand and emission levels of space and water heating, since these two components comprise 76 percent of residential energy demand. Ground source heat pumps (GSHPs) are a technology that provides heating at 25 to 30 percent of the energy consumed by even the most efficient conventional alternatives. GSHPs have been identified as the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available. However, their drawbacks have been high capital costs, and uncertainty about whether the electric power used by heat pumps has higher system-wide emissions. This thesis delineates how adoption of GSHPs in the residential sector can help align Canada’s technology choices with commitments made to the Kyoto Protocol. The manuscripts delineate conditions under which GSHP systems achieve the largest net emission reductions relative natural gas, heating oil, and electric heat counterparts. Electricity generation methods and emissions embodied in inter-provincial and international electricity trade are shown to significantly affect the emission savings achievable through GSHP. The thesis quantifies how relative fuel prices influence annual operating savings that determine how rapidly the technology can achieve payback. This analysis reveals GSHPs to hold significant potential for substantial GHG reductions at a cost savings relative to conventional alternatives; the time horizons for payback are as short as nine years for average-sized homes, and significantly shorter for larger homes.
25

Evaluating the use of marginal abatement cost curves applied to greenhouse gas abatement in the UK agriculture

Eory, Veronika January 2016 (has links)
Climate change is arguably the most important global societal challenge. Developing ‘low-carbon societies’, i.e. reducing greenhouse gas (GHG) emissions and adapting to a changing climate, is becoming a policy goal across the globe. Agriculture plays an important role in this transformation. The sector is highly vulnerable to climate variability, and is a significant source of emissions. At the same time, it has potential for reducing GHG emissions and also provides opportunity for carbon sequestration in soils and crop biomass. Policy support for mitigating GHG emissions is being informed by scientific evidence on the effectiveness and costs of mitigation opportunities. This information is frequently depicted in marginal abatement cost curves (MACCs), an assessment tool which can help to visualise the hierarchy of technical measures and their cumulative level of abatement. Similarly to other assessment tools, MACCs’ suitability to provide information has certain limitations. Furthermore, different derivations of MACCs are appropriate to answer different questions. In order to draw both informative and reliable conclusions for policy decisions, the characteristics of the MACCs and the resulting limitations have to be presented clearly. This dissertation seeks to answer the general question whether the agricultural MACCs can be improved so that they provide more comprehensive and tailored information to policy makers. In particular five limitations of the MACCs are discussed: the lack of representation of wider effects, the issue of cost-effectiveness of policy instruments and the inclusion of transaction costs, the uncertainty in the MACCs, the boundaries and the heterogeneity of the analysis. Theoretical frameworks are developed and case study examples are provided for these limitations, and the frameworks are assessed in terms whether they achieve the goal of providing more comprehensive information to policy makers than a conventional MACC. Furthermore, the dissertation summarises the available methodologies and applications in agriculture to enhance the MACCs and provides guidelines for researchers and policy makers about the choice of methods and the communication of the results in order to improve the use of MACCs in the policy process.
26

Impactos econômicos de políticas de mudança climática na economia brasileira: um estudo a partir de um modelo de equilíbrio geral computável / Economic impacts of policies on climate change mitigation in the Brazilian economy: a study based on a computable general equilibrium model

Jonathan Gonçalves da Silva 03 December 2010 (has links)
O objetivo desta dissertação é estimar os impactos econômicos de cenários de políticas climáticas para o Brasil. Mais especificamente, pretende-se através de um modelo de equilíbrio geral computável verificar como algumas variáveis econômicas respondem à simulação de algumas políticas de mitigação de mudanças climáticas por parte do Brasil. Para tal propósito, utilizou-se o modelo Emissions Prediction and Policy Analysis EPPA do MIT, o qual é um modelo dinâmico-recursivo, multi-regional que representa a economia mundial. Os principais resultados revelaram que a introdução de metas de redução de emissões a partir de 2015, possibilita uma redução expressiva das emissões de GEEs do país, com destaque para a redução proveniente de desmatamento. Quanto ao nível de atividade econômica verificou-se que o sacrifício a ser realizado em termos de perdas do PIB não se mostrou expressivo, o que pode ser explicado por uma matriz energética intensiva em fontes de energia limpa. Em termos de bem-estar, observou-se que a inclusão de metas de redução do desmatamento, como as representadas pela política CP1 trouxeram perdas modestas em bem-estar para o Brasil, ou seja, o esforço no sentido de enquadramento com as metas de Copenhague é benéfico, pois as perdas de bem-estar serão relativamente pequenas, caso o país continue o ritmo de redução em emissões previsto para 2020. / The objective of this dissertation is to estimate the economic impacts of climate policy scenarios for Brazil. More specifically, it is intended through a computable general equilibrium model to see how some economic variables respond to the simulation of some policies to mitigate climate change by Brazil. For this purpose, it was used the Emissions Prediction and Policy Analysis model EPPA, from the MIT, which is a dynamic-recursive model, multi-regional that represents the world economy. The results reveal that the introduction of the targets for reducing emissions from 2015, allows an expressive reduction of GHG emissions in the country, notably the reduction from deforestation. Regarding the level of economic activity showed that the sacrifice being made in terms of GDP loss was not significant, which can be explained by an energy-intensive sources of clean energy. In terms of welfare, it was observed that the inclusion of the targets for reducing deforestation, such as those represented by the policy CP1 brought modest losses in welfare for Brazil, namely the effort to frame the goals of Copenhagen is beneficial, because the loss of welfare will be relatively small if the country can continue the pace of reduction in emissions in 2020.
27

Environmental and techno-economic analysis of ground source heat pump systems

Hanova, Jana 11 1900 (has links)
Climate change stabilization requires an unprecedented effort to change our current approach to energy production and consumption. While rising energy prices are drawing increased attention to reducing energy demand, heightened concern about the environmental consequences of fuel choice requires that this demand be met at lower emission levels. In Canada, the realization of commitments to our GHG emission goals entails reducing residential energy use - a sector responsible for close to 20 percent of end-use energy consumption. This study focuses on the energy demand and emission levels of space and water heating, since these two components comprise 76 percent of residential energy demand. Ground source heat pumps (GSHPs) are a technology that provides heating at 25 to 30 percent of the energy consumed by even the most efficient conventional alternatives. GSHPs have been identified as the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available. However, their drawbacks have been high capital costs, and uncertainty about whether the electric power used by heat pumps has higher system-wide emissions. This thesis delineates how adoption of GSHPs in the residential sector can help align Canada’s technology choices with commitments made to the Kyoto Protocol. The manuscripts delineate conditions under which GSHP systems achieve the largest net emission reductions relative natural gas, heating oil, and electric heat counterparts. Electricity generation methods and emissions embodied in inter-provincial and international electricity trade are shown to significantly affect the emission savings achievable through GSHP. The thesis quantifies how relative fuel prices influence annual operating savings that determine how rapidly the technology can achieve payback. This analysis reveals GSHPs to hold significant potential for substantial GHG reductions at a cost savings relative to conventional alternatives; the time horizons for payback are as short as nine years for average-sized homes, and significantly shorter for larger homes. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate
28

Potentiel de réduction des émissions de GES du transport routier de fret / Potential of road freight GHG mitigation

Tu Thi, Hoai Thu 04 January 2019 (has links)
L’objectif de cette thèse est d’identifier les politiques qui permettraient de réduire les émissions de GES du transport de fret routier au moindre coût pour la collectivité. Pour cela, nous estimons, sur la période 2030-2050, les quantités évitées ainsi que le coût économique dans 6 scénarios correspondant à différentes politiques de réductions des émissions. Le coût économique comprend la somme des coûts pour les utilisateurs de transport et pour les pouvoirs publics ainsi que les coûts des externalités. Nous utilisons, quand ils sont disponibles, des jeux d’hypothèses définis par le ministère des transports, en particulier pour l’évolution des trafics et les valeurs unitaires des externalités. Pour chaque scénario, le coût économique par tonne de GES évitée est très sensible aux hypothèses, en particulier aux valeurs unitaires retenues pour les externalités (valorisation des co-bénéfices). Dans les hypothèses centrales, plusieurs scénarios présentent un coût négatif, c'est-à-dire un bénéfice pour la collectivité en plus de la réduction des émissions. C’est le cas de notamment de la taxe carbone, aussi longtemps qu’elle reste inférieure aux coûts externes engendrés par les poids lourds. Pourtant, quand cette taxe augmente, la hausse correspondante du prix de transport conduit les chargeurs à renoncer à une partie de leur activité, ce qui limite l’augmentation souhaitable. L’augmentation de 40 à 60 tonnes du poids maximum autorisé des poids lourds est une mesure très favorable aux utilisateurs de transport car elle permet de réduire significativement le coût du transport. Prenant en compte les gains d’externalités, la perte fiscale des pouvoirs publics, ainsi que les coûts d’infrastructure (investissement pour renforcer les ponts et les routes et entretien), ce scénario présente également un bénéfice pour la collectivité. Le scénario d’installation de caténaires sur le réseau autoroutier pour permettre la circulation de poids lourds hybrides est efficace en matière de quantité de GES évitée et le coût d’évitement par CO2e reste limité. En revanche, dans le scénario d’électrification du fret urbain (remplacement des camions diesels par des camions électriques dans les villes) le coût de la tonne évitée est élevé si les camions électriques n’ont que deux tonnes de charge utile alors qu’il devient un bénéfice économique si, grâce au progrès technologique, les camions électriques ont 6 tonnes de charge utile en 2030 (pour une autonomie de 100 km).Le remplacement des poids lourds diesels par des poids lourds au Gaz Naturels Véhicules réduit le coût du transport et bénéficie donc aux transporteurs et chargeurs tandis que les pouvoirs publics supportent une perte de recette fiscale. En tenant en compte les gains d‘externalités, cette mesure permettrait un coût économique limité. Enfin, le chargeur a la possibilité de réduire ses émissions de GES, avec un coût raisonnable pour l’entreprise et un bénéfice pour la collectivité, en diminuant la fréquence de ses envois. Pourtant, aucune de ces mesures n’est susceptible d’offrir seule une réduction suffisante des émissions. Pour atteindre l’objectif de facteur 4 à un coût raisonnable pour la collectivité, différentes mesures doivent être envisagées en complément / The purpose of this thesis is to identify policies that would allow to mitigate road freight GHG emissions at the lowest cost for the community. With this in mind, for six scenarios corresponding to different mitigation policies we estimate the mitigated emissions along with the economic cost, over the 2030-2050 period. The overall economic cost includes the cost for transport users, for public authorities, and an economic valuation of transport externalities. When available, we used sets of assumptions retained by the French Ministry of Transports for official traffic projections and for the unitary valuation of external costs. For every scenario, the economic cost by avoided ton of CO2 is highly sensitive to these assumptions, especially to the unitary value of external costs (valuation of co-benefits). In the central set of assumptions, several scenarios result in a negative economic cost of GHG mitigation, id est a benefit to the community in addition to GHG cuts.This is notably the case for the carbon tax, as long as it remains lower than the external costs of freight road transportation. However, when the tax rate is rising, the resulting increase in transport prices leads shippers to reduce their activity, which limits the desirable tax rate increase. Increasing the maximum authorized weight of heavy trucks from 40 to 60 tons would be a very beneficial measure towards transport users by allowing a substantial transport costs reduction. This scenario is also beneficial for the community, when accounting for the avoided external costs, the financial loss for public authorities and infrastructure costs (the required reinforcement of roads and bridges and increased maintenance costs). The installation of catenaries on motorways to supply hybrid heavy trucks is efficient to reduce CO2 emissions, and the economic cost per avoided ton of CO2 remains moderate. Quite the opposite, the economic cost is high in the scenario of electrification of urban freight (where diesel trucks are replaced by electric trucks for urban goods delivery), if electric trucks only have a maximum payload of 2 tons. On the contrary, it turns into an economic benefit if, thanks to technological progress, electric trucks have a payload of 6 tons in 2030, for a range of 100 km.The replacement of diesel trucks by natural gas vehicles reduces transport costs and is therefore beneficial towards carriers and loaders, but public authorities support a loss of taxation revenues. However, when accounting for the avoided external costs, the overall economic cost happens to be limited.Finally, shippers can reduce GHG emissions for a reasonable economic cost by reducing the frequency of shipments, this measure also being beneficial for the community.However, none of these measures is capable to achieve by itself the official goal of dividing by 4 the level of GHG emissions at a reasonable cost for the community, implying that additional measures have to be considered jointly
29

Improvement of the Energy Efficiency and GHG Emissions Management Systems of an O&G Company's E&P Operated Assets

Gómez Blanco, Paula Andrea January 2013 (has links)
The Oil and Gas (O&G) Industry has been one of the most environmentally questioned sectors in the lastdecades, where the management of the resources and impact over natural life has been severelycriticized. There are many adverse effects of the activities around the O&G business, from which theconsumption of energy and the emissions of Greenhouse Gases (GHG) stand out to be one of the mostimportant aspects to mitigate. This project studies the actual EnMS in E&P and develops measures of improvement using establishedmanagement tools in the division, applying the principles of the ISO 50001 Standard, to include energysavings and GHG emissions mitigation in the lifecycle of Repsol’s E&P operated assets. The main focuslands over three core elements: the Integrated Project Management platform for new projects, the EnergyPlanning follow-up applications, and the implementation of relevant energy audit outlines.
30

Carbon Accounting of Transportation Infrastructure.

Le Bourhis, Jean-Marie January 2014 (has links)
Climate change is one of the most important challenges society is facing. Climate change is mainly due to the release of greenhouse gases (GHG) by humans. The transportation sector plays a major role in the release of GHG. However, little effort has been made worldwide for decreasing transportation emissions. Accounting for transportation emissions has become a great concern. SETEC International is one of the leading engineering groups for the design of transportation infrastructure in France. Through this Master’s Thesis, SETEC wanted to develop a carbon accounting tool for calculating GHG emissions from three types of infrastructures: road, railway and airport. This Thesis explains how the carbon accounting tool was designed in order to take into consideration most of the GHG emissions caused by transportation infrastructures. Carbon accounting of an infrastructure aims to determine the elements that emit the most GHG so that design recommendations can be made and the carbon footprint of the infrastructure reduced.

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