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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

Socio-anthropologie des énergies marines renouvelables en Basse-Normandie : gouverner (par) l'alternative / Socio-anthropology of marine renewable energy in Lower Normandy : governing (by) the alternative

Bourdier, Laure 22 November 2019 (has links)
À la suite du paquet Énergie Climat Européen et des Grenelle de l’Environnement, l’État français lance à partir de 2011 une série d’appels d’offres et d’appels à manifestation d’intérêt pour la construction d’infrastructures d’énergies marines renouvelables (EMR) le long des côtes françaises, en particulier en Basse-Normandie, région fortement marquée par son lien avec le nucléaire civil et militaire. Les parties prenantes du développement des EMR y anticipent des problèmes d’« acceptabilité sociale ». L’objet de cette thèse est, à partir de l’étude des acteurs qui concourent au développement des EMR en Basse-Normandie et des dispositifs d’acceptabilité qu’ils mettent en place, d’appréhender le maintien et le renouvellement d’un système énergétique centralisé fondé sur le nucléaire, en y intégrant l’alternative renouvelable. S’appuyant sur une combinaison de techniques d’enquête (observation directe, entretiens, questionnaires, recueil de productions documentaires, de textes réglementaires et de documents biographiques) dont l’analyse s’appuie sur des méthodes principalement qualitatives, ce travail montre que le maintien du système énergétique opère à travers le gouvernement de la critique. Les acteurs locaux, y compris critiques des projets, sont mobilisés par les entreprises, l’État, les collectivités, et les scientifiques à l’aide de dispositifs visant à construire l’acceptabilité sociale. Avec ces dispositifs d’acceptabilité, on n’assiste pas à une transformation des projets techniques vers l’intégration de dimensions sociales, mais davantage à la translation d’enjeux sociaux en termes techniques. / Following the European Union climate and energy package and le Grenelle de l’Environment, the French State launched, from 2011, a series of calls for tender and for expressions of interest for the construction of infrastructures of Marine Renewable Energy (MRE). The planned infrastructures are located along the French coast, particularly in Lower Normandy, a region characterized by the production of civilian and military nuclear power. Stakeholders in the development of MREs anticipated problems of "social acceptability". This thesis, based on a study of the actors who participated in the development of MREs in Basse-Normandie and of the acceptability mechanisms they have put in place, focuses on maintaining a centralized energy system based on nuclear energy, that has integrated the renewable alternative. Based on a combination of survey techniques (direct observation, interviews, questionnaires, collection of documentary productions, regulatory texts and biographical documents) analysed mainly through qualitative methods, this thesis reveals that the maintaining of the energy system operates through the government of critique. Local actors, including those who oppose the project, are mobilized by companies, the state, regional public authorities, and scientists through mechanisms aiming to build social acceptance. Thus acceptability, as an instrument of governing, does not mean a transformation of technical projects towards a better integration of social dimensions, but rather a translation of social questions into technical terms.
2

Energy Dependence of Transition Probabilities and Level Densities Determined from the (n,γ) Reaction

Hughes, Leonard Bland 05 1900 (has links)
<p> High resolution lithium-drifted Germanium detectors have been used to study the γ radiation emitted after thermal neutron capture in ten odd-proton even-neutron nuclei in the mass range 56 ≤ A ≤ 204. From the energies and intensities of these radiations, the energy dependence of the partial radiative widths to bound states with excitation energies in the region 0 to 2.5 MeV have been deduced. The energy dependence for the average spacing between the levels populated in this reaction have also been deduced over the same region of excitation energies. The energy dependence of the partial radiative widths are in agreement with the single particle estimate for dipole radiation and the energy dependence of the average level spacing favours the constant temperature model.</p> / Thesis / Doctor of Philosophy (PhD)
3

Topics in the Theory of Superconductivity

Leavens, Charles Richard 08 1900 (has links)
<p> Simple theoretical expressions for the zero temperature energy gap and the transition temperature of a weak coupling superconductor are derived and applied to an investigation of several phenomena.</p> <p> The anisotropy of the energy gap in aluminium arising from the anisotropy in the phonon spectrum is calculated. The effect of this energy gap anisotropy on some thermodynamic properties of superconducting aluminium is investigated.</p> / Thesis / Doctor of Philosophy (PhD)
4

Energy and sustainability transitions : the case of community renewables for off-grid rural electrification in Nigeria with emphasis on Shape community project

Butu, Ahmed Ibrahim January 2017 (has links)
The transition from one energy system to another has been analysed by many researchers especially in the context of developed countries. Community renewable energy transition in rural areas is largely under-researched, particularly in developing countries. This study developed a model based on indicators from transition theory and concepts to assess the transformative potential of the processes and governance approaches to community renewable energy in accelerating energy and sustainability transition in off-grid communities in Nigeria. The exploratory research adopted a case study approach and analysed renewable energy planning and decision-making processes as well as evaluated the development of a pilot community renewable energy project in Shape rural community in Nigeria. In addition to documentary evidence, the study gathered data primarily by interviewing 24 relevant actors in the Nigerian electricity industry as well as actors involved in the pilot community renewable energy project. The study reveals that the processes and governance approaches adopted are in line with transition theory and have the potential of contributing to the transformation of the rural electricity provision in Nigeria. However, there is still a long way to go for Nigeria to effectively implement an integrated governance approach capable of accelerating the transition processes. The study found that community renewable energy is motivated by several determinants including: the lack of energy accessibility; removing carbon emissions; meeting environmental obligations; achieving energy security; and, addressing cracks in the current system of rural electrification. The study further found a lack of local initiatives at the grassroots level that can add pressure to make the transition happen. The study found the establishment of an arena for the identification of the challenges facing rural communities and development of strategies. However, some prominent actors are not involved in both strategic decision-making and the implementation process. Of concern, the study revealed a lack of clearly defined responsibilities with most of the government agencies carrying out renewable energy activities independently. Similarly, the study found several barriers which are classified as: actor; interaction; institutional; infrastructural; and, socio-political that are challenging the successful transition to community renewable energy. This work contributes to current attempts to operationalise transition theory and concepts to assess on-going transition processes and governance. This is a significant contribution to the literature because it helps in linking theoretical development with sustainability in practice in a developing country context. The study may assist policy makers, communities and other relevant stakeholders in designing an integrated governance framework for renewable energy transition in rural areas.
5

Analysis of Energy Transition Pathways in the Residential Sector of the Built Environment : A sectoral country comparison

Derwort, Pim January 2015 (has links)
An energy transition is currently taking place in many European countries. Existing studies comparing countries’ energy transition pathways are limited in scope and lack a strong theoretical foundation. This thesis addresses the lack of theoretical framework-based approaches by applying a sectoral analysis framework, identifying the main factors facilitating or hindering the sustainable energy transition in several countries, and the significant differences between them.The research focused on four countries; the Netherlands, Denmark, Germany and the United Kingdom and was limited to the residential sector of the built environment. It included the three dominant housing types: social rental; private rental; and homeownership. Data was clustered along the four dimensions of the sectoral analysis framework, identifying: (1) actors, interactions &amp; networks; (2) the institutional or legal framework; (3) the technological framework; and (4) market demand. The same process was repeated for each of the countries, forming a detailed overview about their chosen energy transition pathways. A number of interviews were conducted to gain further insight into country-specific factors.With respect to actors, interactions and networks, this study has found that strong ties and cooperation between ministries and departments is an important factor facilitating policy success, with departmental fragmentation or competition posing a significant barrier. In terms of the institutional framework policy stability, clear targets and long-term policy framework are all factors for policy success. Conversely, frequent changes to existing policies, non-binding goals and the absence of a long-term framework are all seen as barriers for a sustainable energy transition. Looking at the technological regime, this study found countries with active support for renewable energy technologies have a higher share of renewable energy than countries where the choice of technologies is largely market-based. Past technological choices and existing energy-infrastructure were found to influence transition pathways and can be both a positive or negative factor. Lastly, with respect to market demand, the existence of a standardised housing stock was found to be a potentially significant factor for the upscaling of innovative initiatives. The existence of a large and fragmented (private) rental sector and high interest rates on financing products were found to be further barriers for the energy transition in the residential sector.This thesis has identified obstacles matching those in previous studies and introduced a number of factors facilitating policy success. It has made a first step in overcoming the lack in theoretical framework-based approaches in energy transition analysis future studies can build on.
6

Le droit de la transition énergétique, une tentative d'identification / The energy transition law : An attempt of identification

Mauger, Romain 08 September 2017 (has links)
Cette thèse se consacre à l’étude du cadre juridique de la transition énergétique depuis 2012, année depuis laquelle l’expression a connu une utilisation croissante dans le domaine des politiques publiques en matière d’énergie et d’environnement. Le champ des évolutions juridiques frappées du sceau de la transition énergétique est si vaste que ces travaux se sont concentrés sur la règlementation des énergies renouvelables électriques prééminentes que sont l’éolien terrestre et le solaire photovoltaïque. Il en ressort que le droit de la transition énergétique se situe au carrefour d’autres droits plus anciens, plus établis. De nature évolutionnaire plus que révolutionnaire, il se coule dans le cadre existant et se soumet aux principes classiques du droit. De nos travaux ressort notamment qu’il fait un usage immodéré d’instruments de planification le soumettant potentiellement à une obligation de résultats mesurables. Il est aussi amené à intégrer des considérations de justice très contemporaines, liées à sa finalité, faisant de lui davantage qu’un droit purement technique. Toutefois, il a été marqué par une confusion certaine lors du processus de rédaction de la loi relative à la transition énergétique pour la croissance verte, du fait de son volume, de ses conflits et des failles inhérentes aux institutions de la Ve République. Ce contexte n’ayant pas favorisé l’émergence d’un droit stable et de qualité, il manque de sécurité juridique. Enfin, il se révèle être plus souvent un frein qu’un facilitateur pour le développement des énergies renouvelables, alors qu’il est mal écrit et mal armé quand il s’agit d’organiser la diminution de la part du nucléaire dans le mix électrique. / This doctoral thesis aims to study the legal framework of the energy transition in France since 2012. From this year on, the term “energy transition” has been increasingly used in environment and energy-linked public policies. The scope of the legal developments related to the energy transition is so wide that this work has only focused on the rules applicable to renewable sources of electricity, especially onshore wind and solar photovoltaics. As a result, it appears that the energy transition law lies at a crossroads between older and more recognised fields of the Law. Evolutionary more than revolutionary, it fits into the existing frame and submits itself to the classical principles of Law. Among the outcomes of this research, we found that the energy transition law is making a strong use of planning tools, potentially placing it under a measurable performance obligation. It is also forced to integrate very contemporary notions of justice, linked to its finality, denying it the qualification of a solely technical law. However, there was confusion in the writing process of the Energy Transition for Green Growth Act, the flagship energy transition act, because of its size, its conflicts and the inherent flaws of the institutions of the 5th Republic. This context did not promote the emergence of a stable and high-quality law. Actually, it is lacking of legal certainty. Finally, energy transition law is more often than not placing a break on than facilitating the development of renewable energy, while it is badly written and ill-equipped to organise the decrease of nuclear energy into the electrical mix.
7

Supporting energy transitions and miscanthus program development at the University of Iowa

Lain, Kayley Christina 01 May 2017 (has links)
Miscanthus is a highly productive, low-input biofuel crop that supports agricultural diversification with improved performance for climate commitment, energy security, and water quality over first generation biofuels. Despite its high performance, no local or regional markets for the feedstock have formed in North America, and current climate-based productivity assessment methods lack the information farmers and decision-makers need to establish commercial scale bioenergy markets, programs, and thermal co-firing plans. This study develops a Miscanthus Suitability Rating and a transferable field-scale siting method, applied at 10 m resolution across the State of Iowa to assess miscanthus production potential and identify individual farms that are highly suitable for large-scale miscanthus cultivation while maintaining a majority of existing row cropping acreage. Results show that highly suitable fields within 50 miles (84 km) of each of Iowa’s coal-fired electrical generating units (EGUs) can displace up to 43% of current coal consumption. Every EGU in Iowa has land resource to produce local miscanthus to co-fire with other solid fuels at industry-leading levels without significantly impacting local row crop production. Seven of the state’s smaller facilities could even operate exclusively on local miscanthus with advancements in densification technology. The energy evaluation tool developed in this work estimates the energy return on investment (EROI) of Iowa miscanthus for existing thermal generation facilities between 37 and 59, depending on transportation requirements and chemical field applications. This transition would diversify local agribusiness and energy feedstocks, reduce greenhouse gas emissions and provide a sustainable, dispatchable, in-state fuel source to complement wind and solar energy.
8

Present and Future Status of Power-Based Tariffs : Study on the effect of the energy transition on power tariffs and their applicability

Chehade, Youssef January 2021 (has links)
Power and energy tariffs and their pricing are a vital component which form the main source of income for all actors in the energy industry. Different methods of how to price the energy have been proposed and implemented through the past century, each with its respective advantages and disadvantages. However, in the recent decades, interest has turned towards having power-based tariffs, since it’s the power dimensioning that counts for the majority of the costs. Sala-Heby Energi Elnät AB is local, publicly-owned Swedish distribution system operator which has been using a power-based tariff system for the last 15 years. That being said, the company has an upper limit for their net income which should not be overpassed. With the ongoing energy transition, where the number of electric vehicles in circulation is going up, and more customers turning towards residential micro-production, such a tariff might require modifications. In addition, a look on how the demand will evolve will be needed to see if the grid could handle such a transition. In this paper, a thorough study is conducted on how the energy transition would look like in Sala, Sweden, and what Sala-Heby Energi Elnät AB would expect. A simulation of the total residential load curve of the city is developed and ran via MATLAB and consumption data offered by Sala-Heby Energi Elnät AB. It involved generating an average residence based on the fuse size, which would yield the annual consumption profile to be used. The simulations were also done for several scenarios of different electric vehicle charging routines. They also take into account several residential PV systems coverages in the said city. Depending on which scenario, a rise or a drop in the net income is recorded. Modifications to the power tariff are explored based on that would help counter the fluctuations in the income, and simulated to track their effect. Another aspect that is studied is the subscription capacity to the grid by the operator to the respective power generation. Depending also on the scenario, various excessive consumptions peaks are recorded, which could pave the way to more difficulty in handling the grid.
9

The Interdependence of Energy and Sustainability

Favero Bolson, Natanael 11 1900 (has links)
The increasing frequency of extreme weather events is a consequence of changing climate. The direct physical causes are carbon dioxide emissions from the intensive use of fossil fuels and accelerated soil and plant decomposition from alterations in land use. Efforts to avoid a global environmental calamity and engineer a shift towards a more sustainable path are at the forefront of global agenda. However, beyond all the commitments and good intentions, there is no consensus on what constitutes sustainability, the requirements for a power transition towards a post-carbon era, or the energy resources available to achieve economic goals. This dissertation aims to clarify the relationship between energy and sustainability. We begin with a review of capacity factors for the leading power technologies at a global and regional scale to understand performance of these technologies and their potential. To address the challenge of evaluating sustainability, we propose a new approach, the eight-dimensional sustainability octagon. This approach broadens the fundamental pillars of sustainability (social, environmental, and economic), and provides a simple yet robust tool for comparing the sustainability of countries on the Earth. This analysis shows that the world is performing at one-third of achievable sustainability levels. Afterwards, we assess current global energy mix from a primary power perspective and estimate energy savings from- and limitations of electrification. We evaluate the power requirements, nominal power to be installed, infrastructure needs, and carbon dioxide emissions associated with replacing current fossil electricity generation mix with renewables. This evaluation indicates that complete decarbonization of the global power mix is impossible by 2050, and electrification could further delay decarbonization. At a single country level (case study), we analyze connections between the ongoing energy-environmental crisis and population growth to assess the feasibility of achieving the government of Rwanda’s developmental goals, given available power resources. We evaluate Lake Kivu in Rwanda as a complex methane source and energy system. We assess the implicit risks and environmental impacts of large-scale methane production to generate electricity. From our analysis, Rwanda is overpopulated, and the available energy resources can only secure low incomes for the population.
10

Energiomställning inom Sågverksindustrin : En utforskande undersökning av sågverksindustrins framtida energianvändning / Energy Transition in the Sawmill Industry : An exploratory study of the future energy use in the sawmill industry

Fredriksson, Hanna, Andreassen, Daniel January 2023 (has links)
The transition to a fossil-free industry is a current topic, and in Swedish industry, energytransition of existing energy systems is promoted to reduce climate impact. Energy transitioninvolves a structural change in the energy system with a focus on energy use and energysupply. To reduce global greenhouse gas emissions, the transition can be achieved throughelectrification and the use of biomass. Currently, sawmills combust significant amounts of biomass to meet the heat demandof industrial wood drying. As the biomass used is a by-product of the sawmills’ otherproduction processes, this combustion is usually considered sustainable and circular. However,some research indicates that increased biomass usage in several industrial sectors can leadto overexploitation of the resource with negative environmental impacts. Despite thesedisagreements, many argue that bio-based residual flows must be utilised efficiently to meetsociety’s future biomass needs. Against this background, it needs to be examined whether sawmills should continue tocombust biomass or whether an energy transition would be more economically and ecologicallysustainable. The aim of this study is to investigate how energy use in the sawmill industrywill change in the future and what potential consequences this change may have. In addition,the possibilities and feasibility of electrifying the drying process in the sawmill industryare investigated. To achieve this purpose, a literature search and an interview study wereconducted. The results from these parts form the basis for a scenario-based quantitativestudy of the consequences of different energy transition cases. The results show that future energy use in the sawmill industry will be affected by severalfactors. One important factor is the price of biomass, which can provide an incentive toelectrify the energy-intensive drying process. However, it can be challenging to make anelectrified drying process profitable, and until then energy efficiency will be prioritised ratherthan biomass replacement. The results also indicate that electrification of the drying processcan reduce the climate impact, assuming that the electricity source is fossil-free. The releasedbiomass can then be used more efficiently than incineration, and the optimal use may be toproduce long-life products. Clear knowledge gaps have been identified regarding the electrification of the drying processand its potential consequences. Since the sawmill industry is not ready for an energytransition today, there is time to fill these gaps and develop the electrifying processes. Furtherinvestigations should be conducted on various aspects of electrified drying through in-depthmodelling and analysis of the sawmill energy system. Additionally, future studies couldinvestigate the extent of the impact of sawmill biomass release on the surrounding energysystem.

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