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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.
81

Pathways for the Cuban energy transition and its CLEWs interactions

Pehrs, Malin, Partanen, Sascha January 2022 (has links)
Transitioning from an energy system based on fossil fuels to an energy system based on renewables is necessary to limit global warming and comes with both opportunities and challenges. National policies in Cuba look toward the domestic sugar industry for synergies in this transition, and bagasse is projected to play a key role in the future electricity system. Since bagasse only is available during the sugarcane harvesting season, it must be supplemented with other feedstock for power production year-round. Biomass can have important interactions with CLEWs and therefore a nexus approach is important to ensure policy coherence across sectors. This study investigates different pathways for the Cuban energy transition from a CLEWs perspective through a scenario analysis and uses OSeMOSYS as a tool. This study shows that national policies for increased food security, regrowth of the sugar industry, use of energy crops and increased electricity consumption to develop the country compete for land and water resources. While there are currently plenty of resources, compromises will be needed in the medium- to long-term in order to stay within natural boundaries. This is especially true for the water sector since precipitation is expected to decrease in the future due to climate change and since sea level rise will contaminate groundwater. Another effect of climate change is soil degradation which would decrease yields. Increased energy and water inputs to the agricultural sector is known to increase yields in developing countries such as Cuba, which is why an adaptation strategy to maintain yields could be to increase these inputs. However, this would further amplify the pressure on water resources. Exceeding the exploitable internal renewable freshwater resources would then require water inputs from desalination plants which is an energy intensive process, which - if powered by an electricity system with a high share of biopower - could create a vicious cycle. / Omställningen från ett fossilbaserat energisystem till ett förnybart system är nödvändigt för att begränsa den globala uppvärmningen och innebär både möjligheter och utmaningar. Nationella policys i Kuba ser till landets sockerindustri för synergier i denna omställning, och bagass väntas spela en nyckelroll i det framtida elsystemet. Eftersom bagass endast är tillgängligt under sockerrörens skördesäsong måste den kompletteras med andra bränslen för att el ska kunna produceras året om. Biomassa kan ha betydande påverkan på CLEWs varför det är viktigt med en nexusanalys för att säkerställa samstämmighet av policys för olika sektorer. Denna studie undersöker olika tillvägagångssätt för den kubanska energiomställningen ur ett CLEWs-perspektiv genom en scenarioanalys i vilken OSeMOSYS används som modelleringsverktyg. Denna studie fann att nationella policys för ökad trygghet av matförsörjning, återuppbyggnad av sockerindustrin och ökad elkonsumtion för att utveckla landet konkurrerar om land- och vattenresurser. Det finns för närvarande gott om resurser, men på medel och lång sikt kommer kompromisser behövas för att stanna inom naturens gränser. Detta gäller särskilt för vattensektorn eftersom nederbörd väntas minska i framtiden till följd av klimatförändringar och eftersom höjningar av havsvattennivån kommer kontaminera grundvatten. Ytterligare påverkan från klimatförändringarna är markförstöring vilket minskar skörden. Ökad energi- och vattenanvändning i jordbrukssektorn ger vanligtvis högre skörd i utvecklingsländer såsom Kuba, vilket innebär att en anpassningsstrategi för att behålla skördenivån skulle kunna vara att öka dessa. Detta kan dock ytterligare förstärka belastningen på vattenresurserna. Att överskrida de utnyttjbara förnybara färskvattenresurserna skulle kräva avsaltning av vatten vilket är en energikrävande process, vilket - om energiförsörjningen kommer från ett system med mycket biomassa - skulle kunna skapa en ond cirkel.
82

SOCIOTECHNICAL IMAGINARIES OF LOCAL ENERGY TRANSITION : CO-PRODUCING LOCK-INS IN THE STUDY OF ENERGY COMMUNITY ON GOTLAND

Loy, Orlando January 2023 (has links)
The emergence of energy communities entails the development of alternative energy systems, where consumers become active participants in the complex networks of material and semiotic actors. This paper looks at how local sociotechnical imaginaries are performed on island of Gotland, in Sweden. Grounded in Science, technology and society studies and co-production theory, this study provides a framework analysis of a set of documents and an interview, through the identification of conflicting visions, or sociotechnical imaginaries, of energy transition locally. The Swedish energy system is adapting slowly to the changing environment, and conflicts have emerged between national and local imaginaries. Here, the literature fails to provide satisfying arguments around political processes leading to the creation of alternative visions of energy futures. This study shows how normative orientations shape and are shaped by each other, and how alternative visions of progress often fail to be actualized and performed as long as they exist in combination with dominant visions. The two imaginaries, on one side the dominant, on the other the radical, fail to come to terms with each other because of the structural inadequacy of a system dominated by a political rationality which is unaware of itself.
83

Contributions towards closing the intention-behavior gap in residential low-carbon technology adoption decisions

Vogt, Emily Christine 29 July 2024 (has links)
Against the background of an aspired zero emission economy, residential decision making concerning low-carbon technologies (LCTs) has been researched widely to develop appropriate policy measures to foster adoption levels, however, adoption levels remain unexpectedly low. First, prevalent knowledge gaps are caused by the lacking accumulation of knowledge in the research domain, and second, the lacking common understanding of the decision process itself. Third, previous research has not sufficiently accounted for heterogeneity in the population, instead assuming similar drivers and barriers for adoption across consumer segments. Based on an extended Theory of Planned Behavior and previous research findings, a holistic decision framework for residential decision-making concerning LCTs is proposed in this doctoral thesis. A reduced framework could be confirmed for the example technology rooftop PV with a high-quality sample (n=1,800) using Partial Least Squares Structural Equation Modelling. It could be shown, that adoption intention and strength and influence of predictors vary across consumer segments, even between segments with the same broad social status and/or comparable values. Matching survey data with real-world data revealed, that stated adoption intentions of consumer segments are consistent with adoption behavior in Saxonian zip-codes only for two of five consumer segments. Moreover, it could be demonstrated that common variables used to explain adoption intentions (environmental concern and novelty seeking) are not related with adoption levels in Saxonian zip-codes. Similarly, common variables to explain adoption levels in zip-codes (city-type, share of (semi-) detached houses, population density, previous PV installations) are not related with adoption intentions among consumer segments. These results show that taking consumer heterogeneity into account is crucial to understanding drivers and barriers of residential adoption decisions, and that variables relating to intentions and actual behavior are not necessarily equivalent, providing initial insights into why political measures might not have been sufficiently successful yet.:Abstract iii Zusammenfassung v Publications ix Acknowledgments xi 1 Introductory Remarks 1 2 Residential low-carbon technology decision-making 23 3 Residential PV adoption intention 37 4 The decision towards a residential PV system 63 5 Heterogeneity in PV adoption intentions across consumer segments 83 6 Spatial and household characteristics relating to PV saturation 103 7 Spatial and household characteristics relating to PV adoption intention 121 Statement of Contribution xv Curriculum Vitae xvii Declaration of Authorship xix Bibliographic Description xxi
84

The Environmental Mining Dilemma : Interest groups’ perceptions of mining for energy transition metals in Sweden

Nylund, Mia-Lie January 2024 (has links)
The global demand for metals is dramatically surging as global efforts increase to transition to renewable energy and with the electrification of society. The mining industry is heavily criticized for its harmful consequences for the environment, local populations and indigenous communities. The rising demand for renewable energy metals to reduce emissions while also safeguarding the environment and human societies from harm caused by mining pose an environmental dilemma. The Swedish mining industry, with significant metal resources in the bedrock, is aiming to be at the forefront of ‘sustainable’ mining, while environmental organizations, local populations and activists oppose major mining project in Sweden. Understanding the various perceptions from key interest groups is important to understand the foundation of this dilemma. These perceptions may be influential to decision making and responses to the dilemma, affecting both the trajectory of Swedish mining, national metals supply, and future protection of environment and human societies. This thesis uses the methods of semi-structured interviews and frame analysis to examine how interest groups perceive the environmental mining dilemma in the context of Sweden. Identifying two contradicting frames based on fundamentally different environmental values – the dominant societal and the deep ecological – illuminates the foundation based on which interest groups define the problem, argue for which actions should be taken, resonate on self-protection, justification of positions and how to influence others. Beyond the empirical case, the results of this thesis contribute to theoretical knowledge on how perceptions and framing influence the formation of environmental disputes.
85

Synthesis and Characterization of Bronze-Type Mixed Oxides for the Selective Activation of Hydrocarbons

Arriba Mateos, Agustín de 12 February 2024 (has links)
[ES] En este trabajo se ha llevado a cabo un estudio exhaustivo sobre la síntesis, caracterización y reactividad de óxidos metálicos mixtos que presentan la fase ortorrómbica M1, con el fin de conocer la influencia de la composición en las propiedades catalíticas de dichos materiales para la deshidrogenación oxidativa (ODH) de etano a etileno, una alternativa interesante a la producción industrial de olefinas ligeras, lo cual supondría una drástica disminución en la emisión de gases de efecto invernadero. En primer lugar, se ha estudiado la síntesis hidrotermal de óxidos bimetálicos, Mo-V-O que presentan la fase M1, considerando diferentes parámetros sintéticos como la temperatura de síntesis, atmósfera, pH del gel de síntesis, temperatura de activación o post tratamientos de purificación. Los resultados de caracterización indican que la combinación de estos parámetros es clave en la obtención no solo de la fase M1, si no de catalizadores óptimos en la ODH de etano, observándose diferencia de hasta 25 puntos porcentuales en la selectividad a etileno dependiendo de la composición de las especies en la superficie del catalizador. En segundo lugar, se ha investigado la síntesis y caracterización de óxidos trimetálicos, Mo-V-Te-O, que presentan la fase M1 con diferentes proporciones de teluro en la estructura (0 < Te/Mo < 0,17), con el fin modular la acidez, la estabilidad térmica y el comportamiento catalítico de estos catalizadores. Se ha observado que la incorporación de teluro en la estructura de la fase M1 supone un aumento considerable de la estabilidad térmica de los catalizadores, así como de la selectividad a etileno. Posteriormente, se ha llevado a cabo un estudio comparativo entre catalizadores bi-, tri- y tetrametálicos (Mo-V-Te-Nb-O), de la influencia de la composición y/o la activación térmica de los diferentes materiales sobre las propiedades catalíticas. Los resultados obtenidos sugieren una correlación entre la composición superficial y temperatura de activación de los catalizadores con la selectividad a etileno. Así, se ha encontrado una relación directa entre la concentración relativa de especies V4+ en la superficie del catalizador (obtenida mediante de espectroscopia de fotoemisión de rayos-X, XPS) y la selectividad a etileno. Además, y dado que todos estos óxidos mixtos pueden considerarse como semiconductores, se llevó a cabo un estudio electroquímico de los catalizadores. Estos resultados sugieren que, materiales que mostraron una mayor selectividad a etileno, (el catalizador Mo-V-O activado a 400 ºC; y los catalizadores Mo-V-Te-O y Mo-V-Te-Nb-O activados a 600 ºC), presentan una mayor concentración de especies V4+ en la superficie y mayores valores de resistancia eléctrica. Por último, se ha llevado a cabo un estudio comparativo entre los sistemas catalíticos que, en la literatura, presentan los mejores resultados catalíticos para ODH de etano: i) óxido de vanadio soportado sobre alúmina (VOx/Al2O3); ii) óxido de níquel promovido con estaño (Sn-NiO); y iii) el catalizador Mo-V-Te-Nb-O (M1) optimizado en este trabajo. Los resultados catalíticos obtenidos, así como los resultados de caracterización (mediante técnicas de caracterización convencionales e in situ), muestran importantes diferencias en la selectividad a etileno a altas conversiones de etano, como consecuencia de la mayor o menor degradación de etileno en cada catalizador. En ese sentido, el catalizador basado en óxidos mixtos de Mo-V-Te-Nb-O presenta una muy baja reactividad a la combustión de etileno (lo que favorece una alta selectividad durante la ODH de etano), mientras que los otros dos sistemas catalíticos presentan una reactividad para la combustión de etileno mucho mayor (lo que reduce sustancialmente la selectividad a etileno durante la ODH de etano, especialmente a altas conversiones de etano). Estos resultados se discuten en función de las propiedades de adsorción de etano y etileno en cada catalizador. / [CA] En aquest treball s'ha dut a terme un estudi exhaustiu sobre la síntesi, caracterització i reactivitat d'òxids metàl·lics mixtes que presenten la fase ortoròmbica M1, amb la finalitat de conéixer la influència de la composició en les propietats catalítiques d'aquests materials per a la deshidrogenació oxidativa (*ODH) d'età a etilé, una alternativa interessant a la producció industrial d'olefines lleugeres, la qual cosa suposaria una dràstica disminució en l'emissió de gasos d'efecte d'hivernacle. En primer lloc, s'ha estudiat la síntesi hidrotermal d'òxids bimetàl·lics, Mo-V-O que presenten la fase M1, considerant diferents paràmetres sintètics com la temperatura de síntesi, atmosfera, pH del gel de síntesi, temperatura d'activació o post tractaments de purificació. Els resultats de caracterització indiquen que la combinació d'aquestos paràmetres és clau en l'obtenció no sols de la fase M1, si no de catalitzadors òptims en la ODH d'età, observant-se diferència de fins a 25 punts percentuals en la selectivitat a etilé depenent de la composició de les espècies en la superfície del catalitzador. En segon lloc, s'ha investigat la síntesi i caracterització d'òxids trimetàl·lics , Mo-V-Te-O, que presenten la fase M1 amb diferents proporcions de tel·luri en l'estructura (0 < Te/Mo < 0,17), amb la finalitat de modular l'acidesa, l'estabilitat tèrmica i el comportament catalític dels catalitzadors. S'ha observat que la incorporació de tel·luri en l'estructura de la fase M1 suposa un augment considerable de l'estabilitat tèrmica dels catalitzadors, així com de la selectivitat a etilé. Posteriorment, s'ha dut a terme un estudi comparatiu entre catalitzadors bi-, tri- i tetrametàl·lics (Mo-V-Te-Nb-O), de la influència de la composició i/o l'activació tèrmica dels diferents materials sobre les propietats catalítiques. Els resultats obtinguts suggereixen una correlació entre la composició superficial i temperatura d'activació dels catalitzadors amb la selectivitat a etilé. Així, s'ha trobat una relació directa entre la concentració relativa d'espècies V4+ en la superfície del catalitzador (obtinguda mitjançant espectroscòpia de fotoemissió de raigs-X, XPS) i la selectivitat a etilé. A més, i atés que tots aquestos òxids mixtes poden considerar-se com a semiconductors, es va dur a terme un estudi electroquímic dels catalitzadors. Estos resultats suggereixen que, materials que van mostrar una major selectivitat a etilé, (el catalitzador Mo-V-O activat a 400 °C; i els catalitzadors Mo-V-Te-O i Mo-V-Te-Nb-O activats a 600 °C), presenten una major concentració d'espècies V4+ en la superfície i majors valors de resistència elèctrica. Finalment, s'ha dut a terme un estudi comparatiu entre els sistemes catalítics que, en la literatura, presenten millors resultats catalítics per a ODH d'età: i) òxid de vanadi suportat sobre alumina (VOx/Al2O3); ii) òxid de níquel promogut amb estany (Sn-NiO); i iii) el catalitzador Mo-V-Te-Nb-O (M1) optimitzat en este treball. Els resultats catalítics obtinguts, així com els resultats de caracterització (mitjançant tècniques de caracterització convencionals i in situ), mostren importants diferències en la selectivitat a etilé a altes conversions d'età, a conseqüència de la major o menor degradació de l'etilé en cada catalitzador. En eixe sentit, el catalitzador basat en òxids mixtes de Mo-V-Te-Nb-O presenta una molt baixa reactivitat a la combustió d'etilé (el que afavoreix una alta selectivitat durant la ODH d'età), mentre que els altres dos sistemes catalítics presenten una reactivitat per a la combustió d'etilé molt major (el que redueix substancialment la selectivitat a etilé durant la ODH d'età, especialment a altes conversions d'età). Estos resultats es discuteixen en funció de les propietats d'adsorció d'età i etilé en cada catalitzador. / [EN] Herein an exhaustive study on the synthesis, characterization and reactivity of mixed metal oxides that present the orthorhombic M1 phase has been conducted, aiming to unravel the influence of the composition on the catalytic performance of said materials in the oxidative dehydrogenation (ODH) of ethane to produce ethylene, an interesting alternative for the obtention of light olefins, which could suppose a drastic decrease in the greenhouse gas emissions. In a first place, the hydrothermal synthesis of a bimetallic form of the M1 phase, Mo-V-O, has been explored, taking into account all the possible parameters such as temperature, atmosphere, pH of the synthesis gel, activation temperature and post-synthesis treatments. Results indicate that the combination of these parameters is capital not only for the appropriate formation of the M1 phase, but also to the catalytic performance. This is, a set of differently synthesized Mo-V-O catalysts, all of them presenting the M1 phase, may differ in the activity and selectivity to ethylene by up to 25 % depending on the chemical composition on the surface species of the catalyst. Moreover, it was investigated the synthesis and characterization of trimetallic oxides Mo-V-Te-O presenting the M1 phase with different Te-loadings (0 < Te/Mo < 0.17), trying to modulate the acid properties, as well as the thermal stability and catalytic behavior in the ethane ODH. Accordingly, we observed that the introduction of tellurium into the structure of the M1 phase leads to an enhanced thermal stability, in addition to an increase on the selectivity to ethylene. Subsequently, it was performed a comparative study between bi-, tri- and tetrametallic (Mo-V-Te-Nb-O) catalysts about the influence of composition and/or thermal activation on the catalytic behavior. Obtained results suggest that there is a correlation between surface composition, as well as the thermal activation temperature, with the selectivity of these catalysts to ethylene. Then, it was found a direct relationship between surface V4+ species (results from X-ray photoelectron spectroscopy, XPS) and the selectivity to ethylene. Furthermore, since all these mixed oxides can be considered as semiconducting materials, an electrochemical parallel study was also conducted. Then, these results suggest that the oxides that showed the best selectivity to ethylene (i.e., catalyst Mo-V-O activated at 400 ºC; and Mo-V-Te-O and Mo-V-Te-Nb-O catalysts treated at 600 ºC) are also the ones that present the highest amount of V4+ species on the surface of the solid, in addition to the highest values of electric resistance. Finally, a comparative study was performed between the three catalytic systems that have offered the best properties in the oxidative dehydrogenation of ethane in the literature: i) alumina supported vanadium oxide (VOx/Al2O3), ii) tin promoted nickel oxide (Sn-NiO) and iii) multicomponent Mo-V-Te-Nb-O (M1) catalyst optimized in the present thesis. Thus, both the catalytic and the characterization (by means of conventional and in situ techniques) results indicate important differences in the selectivity to ethylene of these catalysts at high ethane conversion values, as a consequence of a greater or lesser degradation of the ethylene over each catalyst. In this sense, the catalyst based on mixed metal oxides, Mo-V-Te-Nb-O, shows a very low reactivity for ethylene deep oxidation (which favors a high selectivity during ethane ODH), whereas the rest of the catalytic systems display higher reactivity for deep oxidation of ethylene (which drastically reduces the selectivity to ethene during ethane ODH, specially at high ethane conversion). These results will be discussed in terms of the different adsorption properties of both ethane/ethene over the three catalytic systems. / Arriba Mateos, AD. (2024). Synthesis and Characterization of Bronze-Type Mixed Oxides for the Selective Activation of Hydrocarbons [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202614
86

Bewertung von Szenarien für Energiesysteme: Potenziale, Grenzen und Akzeptanz

Schubert, Daniel Kurt Josef 24 May 2016 (has links) (PDF)
Die Dissertationsschrift führt im Gegensatz zu bisherigen Ansätzen im Zusammenhang mit der Energiewende einen Perspektivwechsel hin zur gesellschaftlichen Berücksichtigung herbei. Bisherige Szenariostudien richteten ihren Fokus auf die technische Machbarkeit sowie einzelne Kosten- und Umweltaspekte, wie in der Voranalyse gezeigt wird. Die Gesellschaft spielt in diesem Fall eine sekundäre Rolle. Statt einer Berücksichtigung im vorab geschalteten Entscheidungsprozess werden so häufig erst im Anschluss Zeit und Aufwand in die nachgelagerte Überzeugung der Bevölkerung investiert. Der in der Arbeit verfolgte Ansatz setzt konsequent darauf, gesellschaftliche Präferenzen und Barrieren vorab in die Entscheidungsfindung einzubeziehen, damit Entscheidungen selbst nachhaltig Bestand haben. Dazu werden repräsentative Telefonbefragungen genutzt, mit denen einerseits die Präferenzen der Bevölkerung, andererseits die Grenzen der Akzeptanz in Form der Zahlungsbereitschaft ermittelt werden. Erst im Anschluss daran werden Szenariorechnungen durchgeführt, um energiepolitische Handlungsoptionen auch quantitativ bewerten zu können. Bei der anschließenden Gegenüberstellung von gesellschaftlichen Barrieren und Modellergebnissen werden jedoch auch die Grenzen dieses Ansatzes vor Augen geführt: So kann eine aus Bevölkerungsperspektive erwünschte Handlungsoption (hier der Braunkohleausstieg) auch an politischen und rechtlichen Schranken scheitern.
87

Barriers to a biofuels transition in the U.S. liquid fuels sector

O'Donnell, Michael Joseph 05 August 2010 (has links)
Demand for liquid fuels (i.e., petroleum products) has burdened the U.S. with major challenges, including national security and economic concerns stemming from rising petroleum imports; impacts of global climate change from rising emissions of CO2; and continued public health concerns from criteria and hazardous (i.e., toxic) air pollutants. Over the last decade or so, biofuels have been touted as a supply-side solution to several of these problems. Biofuels can be produced from domestic biomass feedstocks (e.g., corn, soybeans), they have the potential to reduce GHG emissions when compared to petroleum products on a lifecycle basis, and some biofuels have been shown to reduce criteria air pollutants. Today, there are numerous policy incentives—existing and proposed—aimed at supporting the biofuels industry in the U.S. However, the Renewable Fuel Standard (RFS) Program stands as perhaps the most significant mandate imposed to date to promote the use of biofuels. Overall, the RFS stands as the key driver in a transition to biofuels in the near term. By mandating annual consumption of biofuels, increasing to 36 bgy by 2022, the program has the potential to significantly alter the state of the U.S. liquid fuels sector. Fuel transitions in the transportation sector are the focus of this thesis. More specifically, the increasing consumption of biofuels in the transportation sector, as mandated by the RFS, is examined. With a well-developed, efficient, and expensive, petroleum-based infrastructure in place, many barriers must be overcome for biofuels to play a significant role in the transportation sector. Identifying and understanding the barriers to a biofuels transition is the objective of this thesis. Although fuel transitions may seem daunting and unfamiliar, the U.S. transportation sector has undergone numerous transitions in the past. Chapter 2 reviews major fuel transitions that have occurred in the U.S. liquid fuels sector over the last half century, including the phasing out of lead additives in gasoline, the transition from MTBE to ethanol as the predominant oxygenate additive in gasoline, and the recent introduction of ULSD. These historical transitions represent the uncertainty and diversity of fuel transition pathways, and illustrate the range of impacts that can occur across the fuel supply chain infrastructure. Many pertinent lessons can be derived from these historical transitions and used to identify and assess barriers facing the adoption of alternative fuels (i.e., biofuels) and to understand how such a transition might unfold. Computer models can also help to explore the implications of fuel transitions. In order to better understand the barriers associated with fuel transitions, and to identify options for overcoming these barriers, many recent research efforts have used sophisticated modeling techniques to analyze energy transitions. Chapter 3 reviews a number of these recent modeling efforts with a focus on understanding how these methodologies have been applied, or may be adapted, to analyzing a transition to biofuels. Four general categories of models are reviewed: system dynamics, complex adaptive systems, infrastructure optimization, and economic models. In chapter 4, scenarios created from a high-level model of the liquid fuels sector (the Liquid Fuels Transition model) are presented to explore potential pathways and barriers to a biofuels transition. The scenarios illustrate different pathways to meeting the requirements of the RFS mandate, and differ based on the overall demand of liquid fuels, how the biofuels mandate is met (i.e., the mix of biofuels), and the status of the ethanol blend limit in the motor gasoline sector. The scenarios are used to evaluate the infrastructure implications associated with a biofuels transition, and illustrate the uncertainty that exists in assessing such a transition. / text
88

Från el till värme : en diskursanalytisk policystudie av energiomställning på statlig, kommunal och hushållsnivå

Perman, Karin January 2008 (has links)
The aim of this thesis is to analyse how space heating for single-family houses, and energy system conversion has been constructed and discussed at national, municipal and household levels. Political documents have been studied, and interviews have been carried out with politicians, civil servants and householders in the municipality of Falun. In order to study and analyse similarities and differences between these three political levels, the following main questions were asked: In which sense is the use of electrical heating formulated as problematic? How are the causes of these problems presented, and which solutions are suggested? What are the effects of how problems, causes and solutions are constructed? At the national level, the use of electricity produced by nuclear power was considered a problem. Initially the municipality’s policy documents present the same problem, but there is a change of focus to the problem of imported electricity produced by fossil fuel, and the resulting emissions. At household level, the problem was often an old and badly functioning space-heating system. But some households did not formulate a problem before they converted. Instead they were influenced by their neighbours and thereby convinced. At all three political levels, there is consensus on the households’ responsibility concerning energy transition. While industry tends to be considered incapable of cutting down its energy consumption, households are expected to take the responsibility seriously. Furthermore, within the household, the heating system tends to be constructed as a predominantly male concern. At all three levels, households are perceived as dependant on economical subsidies when taking the decision to convert from electrical heating. Although it is interesting that the interviewed householders only apply this view to others than themselves. They are convinced that other households need subsidies to act in an environmentally correct way. The discourse concerning the Swedish energy transition illustrates a shift away from a definition of ecological modernisation where environmental considerations influence economic development. The thesis clearly shows how economic arguments repeatedly influence environmental concerns. However, the tension between the two is played down and concealed through the lack of problematisation of the responsibility of industry, and through the focus on the need for education and future opportunities. Political dialogues concerning the use of electrical heating and the conversion of energy systems towards more renewable energies are dominated by economic arguments at the three levels. One effect of this is an assumption that energy policy instruments such as information and economic subsidies are essential for the energy transition. However, if householders rather are influenced by their neighbours should the government use economic subsidy as the main energy policy instrument?
89

Renewable Energy Transition: Dynamic Systems Analysis, Policy Scenarios, and Trade-offs for the State of Vermont

Clement, Christopher Ernest 01 January 2016 (has links)
There is broad consensus that a transition to renewable energy and a low-carbon economy is crucial for future development and prosperity, yet there are differing perspectives on how such a transition should be achieved. The overarching goal of this dissertation, which is comprised of three interrelated studies, is to analyze and compare energy futures scenarios to achieve a renewable energy transition and low-carbon economy in the State of Vermont. In the first study, an analysis is presented of the role of energy pricing regimes and economic policy in the context of pursuing a renewable energy transition in the State of Vermont. Through the development and application of a system dynamics model, results address the limits to technological substitution due to path dependence on nonrenewable energy. The role of complementary economic policy is also highlighted to shift from a goal of quantitative growth to qualitative development in order to decouple economic welfare from energy consumption. In the second study, an analysis is presented of the impact of modeled energy transition scenarios to address energy development and land use trade-offs. Simulations with a spatio-temporal land cover change model find that Vermont could achieve a complete transition to renewable electricity using in-state resources through developing between 11,000 and 100,000 hectares of land for solar and wind, or up to four percent of state land area, including some environmentally sensitive land. This approach highlights the need for integration of energy policy and land use planning in order to mitigate potential energy-land use conflict. In the final study, trade-offs between energy, economic, environmental, and social dimensions of Vermont's renewable energy transition are explored through the use of a multi-criteria decision analysis. Energy transition alternatives were designed to reveal trade-offs at the intersection of economic growth and carbon price policy. While there were no optimal pathways to achieving Vermont's energy transition, some energy transition alternatives achieve a more socially desirable balance of benefits and consequences. Navigating the trade-offs inherent in the ongoing energy transition will require an adaptive approach to policymaking that incorporates iterative planning, experimentation, and learning.
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Modelos de transição energética residencial e o acesso a serviços energéticos limpos: uma análise a partir de dois estudos de caso / Residential energy transition models and the access to clean energy services: an analysis based on two case studies

Sgarbi, Felipe de Albuquerque 02 August 2013 (has links)
A transição energética residencial começou a receber especial atenção da comunidade científica nos anos 1970 e 1980, quando se acreditava na ocorrência iminente da Crise da Lenha. Na época, temia-se que o corrente ritmo de consumo de biomassas sólidas em países em desenvolvimento ultrapassaria a capacidade de produção primária dos ambientes naturais, com sérias consequências para as camadas menos abastadas da população destes locais, que se veriam em uma situação de escassez de fontes de energia. Apesar de esta crise nunca haver, de fato, se concretizado, a preocupação com a sua potencial ocorrência estimulou o desenvolvimento de modelos que visavam à interpretação do fenômeno da transição energética residencial decorrente do processo de urbanização e aumento de renda dos usuários finais. Tal interesse culminou na elaboração do modelo da Escada Energética que, de uma maneira geral, previa que o abandono de fontes de energia tradicionais e a adoção de fontes de energia modernas era o resultado do aumento do status social da população. Inicialmente, a Escada Energética se estabeleceu como principal modelo de transição energética residencial. À medida que novos estudos foram desenvolvidos, entretanto, evidências passaram a sugerir que diversos fatores envolvidos na transição energética em países em desenvolvimento não podiam ser explicados pelo modelo. Estas evidências subsidiaram a concepção do modelo do Acúmulo de Combustíveis, segundo o qual a diversificação, e não a substituição, de energéticos seria o resultado do desenvolvimento social da população. Atualmente, não existe consenso sobre qual modelo melhor reflete o fenômeno da transição energética residencial. Como consequência, políticas públicas de acesso a energia e serviços energéticos limpos baseadas nestas diferentes interpretações possuem características e resultados distintos. Neste contexto, o presente trabalho pretende contribuir para a discussão sobre qual modelo de transição energética melhor reflete a realidade dos consumidores residenciais de energia de países em desenvolvimento a partir da apresentação de dois estudos de caso que retratam diferentes facetas da questão. As análises elaboradas indicam que o modelo do Acúmulo de Combustíveis consegue representar com maior fidelidade o fenômeno da transição energética residencial e que políticas públicas estruturadas segundo seu arcabouço teórico podem contribuir mais eficazmente para a melhoria das condições de vida da população. / The residential energy transition began to receive special attention from the scientific community in 70s and 80s, when a Fuelwood crisis was believed to be imminent. At the time, it was feared that the current rhythm of solid biomass consumption would not keep pace with the primary productivity of the forests and other sources of fuelwood, with severe consequences striking the least wealthy households, who would face an energy shortage. Although the referred crisis never really happened, the concern with its potential occurrence stimulated the development of models aiming at interpreting the energy transition phenomenon provoked by the urbanization process and the increase in income of households. Such interest culminated in the elaboration of the Energy Ladder model, which indicated that the abandonment of traditional energy sources and the adoption of modern ones was the result of the increase of the social status of the population. Initially, the Energy Ladder established itself as the main residential energy transition model. As new studies were being developed, however, evidences suggesting that different factors related to the energy transition in developing countries couldnt be explained by the model were found. These evidences supported the conception of the Fuel Staking model, according to which diversification, instead of substitution, resulted from the social development of the population. Currently, there is no consensus on which model better represents the residential energy transition. As a consequence, public policies focused on clean energy and energy services access based on these different interpretations have different characteristics and results. In such context, this work intends to contribute to the discussion on which energy transition model better reflects the reality of households in developing countries by presenting two case studies showing different aspects of the thematic. The analysis presented suggests that the Fuel Stacking model can better represent the residential energy transition phenomenon and that public policies structured according to its theoretical framework are more effective in contributing to increase the living standards of the population.

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