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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.
431

Computational Methods for Renewable Energies: A Multi-Scale Perspective

Diego Renan Aguilar Alfaro (19195102) 23 July 2024 (has links)
<p dir="ltr">The urgent global shift towards decarbonization necessitates the development of robust frameworks to navigate the complex technological, financial, and regulatory challenges emerging in the clean energy transition. Furthermore, the increased adoption of renewable energy sources (RES) is correlated to the exponential growth in weather data research over the last few years. This circular relationship, where big data drives renewable growth, which feeds back the data pipeline, serves as the primary focus of this study: the development of computational tools across diverse spatial and temporal scales for the optimal design and operation of renewable energy-based systems. Two scales are considered, differentiated by their primary objectives and techniques used. </p><p dir="ltr"> In the first one, the integration of probabilistic forecasts into the operations of RES microgrids (MGs) is studied in detail. It is revealed that longer scheduling horizons can reduce dispatch costs but at the expense of forecast accuracy due to increased prediction accuracy decay (PAD). To address this, a novel method that determines how to split the time horizon into timeblocks to minimize dispatch costs and maximize forecast accuracy is proposed. This forms the basis of an optimal rolling horizon strategy (ORoHS) which schedules distributed energy resources over varying prediction/execution horizons. Results offer Pareto-optimal fronts, showing the trade-offs between cost and accuracy at varying confidence levels. Solar power proved more cost-effective than wind power due to lower variability, despite wind’s higher energy output. The ORoHS strategy outperformed common scheduling methods. In the case study, it achieved a cost of \$4.68 compared to \$9.89 (greedy policy) and \$9.37 (two-hour RoHS). The second study proposes the Caribbean Energy Corridor (CEC) project, a novel, ambitious initiative that aims to achieve total grid connectivity between the Caribbean islands. The analysis makes use of thorough data procedures and optimization methods for the resource assessment and design tasks needed to build such an infrastructure. Renewable energy potentials are quantified under different temporal and spatial coverages to maximize usage. Prioritizing offshore wind development, the CEC’s could significantly surpass anticipated growth in energy demand, with an estimated installed capacity of 34 GW of clean energy upon completion. The corridor is modeled as an HVDC grid with 32 nodes and 31 links. Underwater transmission is optimized with a Submarine-Cable-Dynamic-Programming (SCDP) algorithm that determines the best routes across the bathymetry of the region. It is found that the levelized cost of electricity remains on the low end at \$0.11/kWh, despite high initial capital investments. Projected savings reach \$ 100 billion when compared with ”business-as-usual” scenarios and the current social cost of carbon. Furthermore, this infrastructure has the potential to create around 50,000 jobs in construction, policy, and research within the coming decades, while simultaneously establishing a robust and sustainable energy-water nexus in the region. Finally, the broader implications of these works are explored, highlighting their potential to address global challenges such as energy accessibility, prosperity in conflict zones, and sharing these discoveries with the upcoming generations.</p>
432

L'énergie nucléaire et le droit international public / Nuclear energy and public international law

El Jadie, Amna 29 June 2017 (has links)
Tous les États sans discrimination ont un droit inaliénable de développer les utilisations de l'énergie nucléaire à des fins civiles, à condition de ne pas détourner ces utilisations pacifiques vers des armes nucléaires. Cependant, il est accordé à cinq pays le droit de posséder ces armes, à savoir les États-Unis, la France, la Russie, la Chine et le Royaume-Uni. Autour de cette position, un vif débat à la fois juridique et éthique a été soulevé. En effet, pour ses opposants, le nucléaire représente un risque durable et non maîtrisable par la science. Les accidents nucléaires majeurs, les déchets radioactifs et le détournement du nucléaire à des fins militaires sont des risques ingérables et d‟une gravité exceptionnelle. En revanche, les défenseurs de cette énergie la présentent comme sûre, voire partie prenante du développement durable. Selon eux, le nucléaire est un moyen fiable de lutter contre le réchauffement climatique et aussi une solution à la pénurie énergétique à laquelle le monde est confronté. En examinant et analysant la fiabilité et la crédibilité de tous les arguments allant à l‟encontre et en faveur de cette industrie, on constate que la licéité et la légitimité du recours à l'énergie nucléaire sont mal fondées. Par conséquent, nous estimons qu‟il est nécessaire de dépasser le nucléaire par la conclusion d'une convention internationale posant l'interdiction progressive mais complète du nucléaire. / All states without discrimination have an inalienable right to develop the uses of nuclear energy for civilian purposes, provided they do not divert these peaceful uses to nuclear weapons. However, five states have been granted the right to possess these weapons, that is : United-States, France, Russia, China and United-Kingdom. Around this position a fierce debate, both legal and ethical, has been raised. Indeed for its opponents nuclear represents a persistent risk that is non controllable by science. Major nuclear accidents, radioactive wastes and the use of nuclear for military purposes are unmanageable risks of exceptionnal serious gravity. On the other hand, the proponents of this energy present it as safe, even as part of sustainable development. According to them, nuclear is a reliable means to fight global warming and is also a solution to the energy shortage the world is facing. When analyzing the reliability and the credibility of all arguments for and against this industry, it can be noticed that the lawfulness and legitimacy of the use of nuclear energy are ill-founded. Therefore, we believe there is a need to go beyond nuclear with the conclusion of an international convention dealing with the progressive but comprehensive nuclear ban.

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