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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

Electric cars : The climate impact of electric cars, focusing on carbon dioxide equivalent emissions

Ly, Sandra, Sundin, Helena, Thell, Linda January 2012 (has links)
This bachelor thesis examines and models the emissions of carbon dioxide equivalents of the composition of automobiles in Sweden 2012. The report will be based on three scenarios of electricity valuation principles, which are a snapshot perspective, a retrospective perspective and a future perspective. The snapshot perspective includes high and low values for electricity on the margin, the retrospective perspective includes Nordic and European electricity mix and the future perspective includes electricity on the margin for modest and high climate goals at 2030. The study is applied to an upcoming climate smart district, Brunnshög in Lund, and the goal is to determine the amount of emissions of carbon dioxide equivalents for the mentioned alternatives. The environmental effects depends largely on the fuel consumption for the compared types of cars and what electricity valuation principle that is used. The car fleet of 2012 generated 10 300 tonnes of carbon dioxide emissions. The future car fleet generated 400 tonnes of emissions for Nordic electricity mix, 3 200 tonnes for European electricity mix, 3 100 tonnes for electricity on the margin with low values, 5 800 tonnes for electricity on the margin with high values, 1 200 tonnes for electricity on the margin at 2030 for high climate goals and 4 600 tonnes for electricity on the margin at 2030 for modest climate goals. The emissions of carbon dioxide equivalents are at least halved in Brunnshög if 100 % electric cars are used instead of the composition of petrol, diesel and ethanol cars that are primarily used in Sweden 2012. Hence, the result shows that the electric car is very beneficial from an environmental and health perspective, compared to the composition of cars in Sweden 2012. However, how beneficial the electric car is, largely depends on the fuel consumption for both the electric car and the alternative compared with. Although to be able to increase the use of electric cars there are many challenges that need to be dealt with. In order to increase the use of electric cars, it will require further work in the development of batteries, expansion of charging points and other incentives, such as legislation and investments. It will also require a significant technology development to increase the range of the electric car. A natural step in the transition phase could be plug-in hybrids. It is also important to continue to implement climate smart districts, such as Brunnshög in Lund.
2

Quantifying the economic and environmental tradeoffs of electricity mixes in Texas, including energy efficiency potential using the Rosenfeld effect as a basis for evaluation

Lott, Melissa Christenberry 16 February 2011 (has links)
Electricity is a complex and interesting topic for research and investigation. From a systems level, electricity includes many steps from its generation (power plants) to transmission and distribution to delivery and final use. Within each of these steps are a set of tradeoffs that are region-specific, depending heavily on the types of generation technologies and input fuels used to generate the electricity. These tradeoffs are complex and often not positively correlated to one another, producing a web of information that makes conclusions regarding the net benefit of changes to the electricity generation mix unobvious and difficult to determine using general rules of thumb. As individuals look to change the mix of technologies and fuels used to generate electricity for environmental or economic reasons, this complex web results in a lack of clarity and understanding of the consequences of particular choices. Quantitative tools could provide individuals with clear information and improved understanding of the tradeoffs associated with changes to the electricity mix. Unfortunately, prior to this research, no such tools existed that provided a clear, rigorous, and unbiased quantitative comparison of the region-specific environmental and economic tradeoffs associated with changes to the electricity mix. This research filled this gap by developing a methodology for calculating the environmental and economic impacts of changes to the electricity generation mix for individual regions. This methodology was applied specifically to Texas to develop the Texas Interactive Power Simulator (TIPS), an interactive online tool accessible via the internet. This tool is currently used for direct instruction at The University of Texas at Austin for undergraduate courses. Preliminary data were collected to determine the usefulness of this tool as a classroom aid. These data revealed that a majority of students enjoy using the TIPS tool, felt that they learned about the tradeoffs of electricity generation methods by using TIPS, and wish that there were more learning tools like TIPS available to them. This research also investigated the potential to use energy efficiency to satisfy a portion of the electricity demand that would otherwise be supplied using a generation technology. The methodology and series of decision criteria that were developed with this investigation were used to determine the amount of generation that could reasonably be satisfied with energy efficiency technologies and supportive policies for a particular region of interest, in this case Texas. This methodology was established using the Rosenfeld Effect as a basis for evaluating the energy efficiency potential in a specific region, providing a more realistic maximum energy efficiency value than using theoretical maximum gains based on current best available technology. It was then compared to efficiency potential estimates by the American Council for an Energy-Efficient Economy (ACEEE) and the Public Utility Commission of Texas (PUCT). In this research, I found that Texas is unlikely to realize more than an annual savings of 11% or about 1.5 megawatt-hours per capita compared to 2007 use levels based on nominal energy efficiency approaches. When this potential savings was applied to offset future demand increases in Texas, it was found that new generation capacity would still be needed over the next few decades to meet increasing total electricity demand. I used the economic and environmental tradeoff analysis and energy efficiency limitations methodologies that I established in my research to calculate the economic and environmental tradeoffs of changes to the electricity mix resulting from several scenarios, including federal energy and climate legislation, nuclear renaissance, high wind power growth, and maximizing energy efficiency. The outputs from these scenarios yielded the following observations: 1. Energy efficiency is unlikely to replace more than 11% of total per capita electricity demand in Texas. This level of energy efficiency might reduce total demand in the state, but population growth and its corresponding impacts on state electricity use might outpace the savings from energy efficiency in the long-term. This population growth could result in an overall increase in total annual state electricity use, despite energy efficiency gains. 2. While nuclear power might be environmentally advantageous from the standpoint of total emission of greenhouse gases compared to fossil fuel-fired power plants, it has very high up-front capital costs and is very water-intensive. 3. A federal combined energy efficiency and renewable portfolio standard might require states to install new renewable power generation capacity. In some states, including Texas, the amount of required new generation capacity may be small because of existing state initiatives encouraging renewable generation capacity to be installed in the state and the potential to offset some generation requirements using energy efficiency. / text
3

The Value of Value Factors : Time-dependent Development of Value Factors on the Swedish Electricity Market

Särnblad, Sara, Ekström, Nora, Vanky, Katarina, Bråve, Agnes January 2020 (has links)
This bachelor thesis investigates the development of value factors on the Swedish electricity market and how the development can be explained. Value factor is a parameter that indicates how well an energy source’s market price corresponds to the average spot price for the electricity mix. Value factors for nuclear-, thermal-, wind-, solar- and hydropower are calculated for the years 2014-2019. Electricity production- and spot price data has been sourced from Svenska Kraftnät, Nord Pool and Uppsala University. The influence of weather conditions, spot price, production and consumption on the development of the value factors is discussed. The Pearson correlation coefficient is used for analytical purposes, showing the correlation between two specific variables. The conclusion is that the value factor for each power source is the result of the conditions present during the specific time period. The value factors for solar- and thermal power are discontinuous since they are temperature-dependent. For nuclear-, wind- and hydropower, the value factors are more continuous during the time span. This is due to, for instance, their important roles in the Swedish energy system and their ability to match demands.
4

Modellering och simulering av uppvärmning och nedkylning av kontorsbyggnad, via HVAC system där fjärrvärme och fjärrkyla jämförs med borrhålslager som energikälla

Forsberg, Anton January 2018 (has links)
An office building (sthlm new hus 4) located in the south of Hammarbyhamnen overlooking Hammarbybacken is planned in 2018. Climate control of the office building are via radiators, high-temperature chilled beam and pre-treated supply air. The building is currently being designed for district heating and remote cooling. The study aims to investigate whether borehole thermal energy system (BTES) are a reasonable alternative to provide the office building with heat and cooling, from an environmental- and life cycle cost (LCC) perspective. The aim of the study is to generate an energy requirement for the office building, which is done by construct a model of the building using IDA ICE, a simulation software. The energy requirement is covered by either district heating/-cooling (energy system I) or BTES (energy system II) as the primary energy source. A model of the BTES is constructed in excel based on data from experience input. Life cycle cost analysis are used for economical comparison between the energy systems. The environmental assessment is based on Nordic electricity mix, which controls the impact of the energy systems. Energy system II entails a need for energy support to avoid over dimension the heat pump, which is done by complementing the surplus need through district heating and remote cooling. LCC shows an economic breakpoint at 11-year calculation period, where BTES becomes economically advantageously. Environmentally, energy system II releases 14.3 tonnes of CO2eq compared to energy system II which results in a reduced emission of 47 tonnes of CO2eq based on Nordic electricity mix.
5

Towards a Neighborhood-Scale Carbon Calculator

McKinley, Samuel Andrew 10 August 2009 (has links)
No description available.
6

Analyse de mix électriques pour la détermination d'inventaires électricité pour ACV conséquentielle / Electricity production mix analysis to determine electricity inventories for consequential LCA

Herbert, Anne-Sophie 06 February 2018 (has links)
La lutte contre le changement climatique implique de modifier les modes de production et de consommation actuels pour réduire de façon drastique les émissions de gaz à effet de serre dont la grande majorité est liée à la combustion d’énergies fossiles. Face à ces enjeux, de nombreux pays se sont engagés dans une transition énergétique pour faire évoluer leur système énergétique, notamment électrique de façon à répondre en partie aux exigences d’une économie bas carbone. Pour guider les acteurs dans leurs choix stratégiques, des outils d’aide à la décision s’avèrent efficaces pour identifier les leviers potentiels de réduction des impacts environnementaux, notamment par la méthode d’Analyse du Cycle de Vie (ACV) qui évalue les impacts d’un produit sur tout son cycle de vie. L’un de ses développements, l’ACV conséquentielle, vise à analyser les impacts d’un changement, et prend donc en compte ses effets directs et indirects sur l’environnement. Cette méthode reste encore peu utilisée par les praticiens en raison du manque d’inventaires génériques pour ACV conséquentielle. Ce constat est d’autant plus marquant pour l’électricité, largement utilisée dans la technosphère, dont la production évolue significativement pour s’engager dans la transition énergétique. Les travaux présentés ici visent à proposer une méthode d’élaboration d’inventaires électricité génériques pour ACV conséquentielle, qui intègrent les spécificités techniques du produit électricité, à travers le bouquet énergétique ou mix qui combine les différents moyens de production, variables selon le pays considéré. Afin de parvenir à simplifier les mix de production d’électricité, une typologie est établie à partir de l’étude des émissions de Gaz à Effet de Serre (GES), des mix et de leur décomposition en moyens de production. Elle identifie 4 groupes de pays, classés par émissions GES croissantes, i.e., 0-37 gCO2eq/kWh, 37-300 gCO2eq/kWh, 300-600 gCO2eq/kWh et >600gCO2eq/kWh, et qui possèdent des caractéristiques de composition spécifiques. Afin de se positionner dans une perspective conséquentielle, l’évolution de douze mix électriques de 1960 à 2010 est analysée. L’analyse historique des phénomènes de transition, c’est-à-dire le passage d’un groupe à un autre de la typologie, est ensuite proposée. Un modèle basé sur une optimisation mono-objectif impliquant, dans un premier temps, un critère de minimisation des émissions GES, et puis dans un second temps, un critère de maximisation de la production d’origine renouvelable est développé. Les résultats sont discutés sur la base des données historiques. La méthode développée reste cependant suffisamment générique pour s’appliquer à des évolutions futures de mix. Enfin, une méthode d’élaboration des inventaires génériques est proposée. Prenant en compte les différentes situations auxquelles le praticien pourrait être confronté lors de la réalisation d’une ACV conséquentielle d’un produit, elle rend possible l’élaboration des inventaires électricité génériques pour ACV conséquentielle. L’établissement de données génériques quantifiées nécessiterait l’intégration d’un critère qualitatif d’inertie au changement et la validation de plusieurs cas d’étude à travers une étude statistique pour consolider les résultats / Climate change mitigation involves changes in production and consumption ways to boost a radical decrease in Greenhouse Gases (GHG) emissions, which come mostly from fossil fuels combustion. To meet these challenges, a lot of countries initiated an energy transition to switch to new energy system, especially concerning electricity production, in such a way that they partly fulfil low carbon economy requirements. To provide decision-makers guidance in their strategic choices, decision-aid tools are useful to identify and reduce environmental impacts burdens. In particular, Life Cycle Assessment (LCA) which assesses environmental impacts throughout a product's life cycle is now a recognized and standard approach. Consequential LCA (cLCA), one of its most recent developments, assesses changes consequences considering either direct or indirect effects on environment. Currently, due to the lack of generic consequential Life Cycle Inventories (LCI), cLCA is scarcely used by practicioners. This situation is emphasized for electricity, due to its large involvement in technosphere and its shifts to production modes in the context of energy transition. This work aims at the development of a design methodology for generic inventories for consequential LCA, taking in account electricity technical specificities. Electricity is defined here as a different production means combination (a “mix”) which varies from country to country. To simplify electricity production mix, a typology is set using a GHG emissions study and electricity mix separation in production means. The typology identifies four groups, ranked by increasing GHG emissions, i.e, 0-37 gCO2eq/kWh, 37-300 gCO2eq/kWh, 300-600 gCO2eq/kWh and >600 gCO2eq/kWh, and specific compositions. Considering a consequential perspective, an evolution analysis of twelve selected countries from 1960 to 2010 is then conducted. Thus, an analysis of past transitions, i.e., shifting from a group to another, is given. Amono-objective optimisation model is developed, involving, first, the minimisation of GHG emissions, and secondly, the maximisation of renewable sources contribution. Significant results are then discussed based on historical data. The model is yet generic enough and can be applied to future mixes. Finally, a generic inventory development method for consequential LCA is proposed. Taking into account the different situations that practitioners may potentially meet when performing a consequential LCA of a product, the method makes generic inventory development for consequential LCA possible. The establishment of generic data would yet require the addition of a qualitative inertia-tochange criteria and the validation of various cases using a statistical analysis to strengthen the obtained results.

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