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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.
61

Desenvolvimento da competição e da infra-estrutura na industria de gas natural do Brasil / Developing competition and intrastructure in the natural gas industry in Brazil

Sant'Ana, Paulo Henrique de Mello 13 August 2018 (has links)
Orientadores: Gilberto de Martino Jannuzzi, Sergio Valdir Bajay / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica. / Made available in DSpace on 2018-08-13T07:43:38Z (GMT). No. of bitstreams: 1 Sant'Ana_PauloHenriquedeMello_D.pdf: 2598332 bytes, checksum: 2f261558acbb7fb96d777666818bcdad (MD5) Previous issue date: 2009 / Resumo: Nos últimos 20 anos, inúmeros países vêm realizando reformas estruturais na indústria do gás natural, buscando a eficiência e a racionalidade econômica através da introdução da competição em determinadas etapas da cadeia. A presente tese buscou responder à seguinte pergunta: Qual é o arcabouço legal e regulatório adequado para a atração de investimento e o desenvolvimento da competição na indústria do gás natural no Brasil, considerando-se o atual estágio de desenvolvimento desta indústria no país? Para tanto, o trabalho efetuou uma fundamentação teórica sobre a teoria da regulação, analisou a experiência internacional na reestruturação do setor de gás natural, as particularidades do regime legal e regulatório no Brasil, a experiência brasileira da reestruturação do setor elétrico e a Lei 11.909/09, conhecida como a Lei do gás. Com o provável excedente de oferta de gás natural a partir de 2011 no Brasil, haverá condições propícias para o desenvolvimento da competição em algumas etapas da cadeia da indústria do gás. Dentre os principais pontos do arcabouço legal e regulatório considerado ideal para a atração dos investimentos e do desenvolvimento da competição, destacam-se: 1) regime único de autorização para a construção de gasodutos de transporte, vinculado a um parecer da EPE sobre o planejamento do mercado a ser conectado; 2) Planejamento participativo, coordenado pela EPE; 3) Acesso e prazo de carência a ser elaborado caso a caso pela ANP; 4) Regulação tarifária para as atividades de transporte 5) Foco na transparência de informações; 6) Criação de uma câmara de comercialização de gás natural; 7) Estimular o livre acesso, uma regulação tarifária eficaz e a transparente no downstream. / Abstract: During the last 20 years, several countries have been carrying out structural reforms in the natural gas industry, trying to achieve efficiency and economic rationality with the introduction of competition. The objective of the thesis is to review the Gas Law 11.909/09 in Brazil and present an analytic approach to the development of competition and infrastructure of the Brazilian natural gas industry. According to the market projection carried out in this work, by 2011 there will be a possible surplus of natural gas in the country. The critical revision of the Gas Law shows several positive points and others that need improvements. This analysis and the new approach proposed herein seek to stimulate the development of competition and infrastructure in the Brazilian natural gas industry. It tries to stimulate it through non-discriminatory open access, tariff regulation for the transport activities and information transparency. The government role in this process is also shown, that is mainly regulation and outlook activities, aiming the development of the infra-structure. The main points to achieve a sound legal and regulatory framework are: 1) authorization for transmission activities, with the requirement of the opinion of the government research company EPE; 2) Participative planning; 3) Open access and exclusiveness period to be elaborated in a case by case basis by ANP; 4) Tariff regulation for transmission; 5) Focus on information transparency; 6) Creation of a wholesale market; 7) Granting open access and tariff regulation on the distribution. / Doutorado / Doutor em Planejamento de Sistemas Energéticos
62

Variabilidade hidroclimatológica e seus efeitos no suprimento de energia elétrica do sistema interligado nacional / Hydroclimatological variability and their effects on electric power supply of the national interconnected system

Tiezzi, Rafael de Oliveira, 1981- 01 August 2015 (has links)
Orientador: Paulo Sérgio Franco Barbosa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-26T09:44:49Z (GMT). No. of bitstreams: 1 Tiezzi_RafaeldeOliveira_D.pdf: 10672810 bytes, checksum: 5a4742f1807a1976eee5fd029668e096 (MD5) Previous issue date: 2015 / Resumo: A variabilidade hidroclimatológica seja na forma de secas ou na forma de anomalias temporais e/ou volumétricas nas precipitações é um problema enfrentado por muitos países e regiões do mundo. Estes fenômenos afetam de forma severa todos os usos da água sejam eles para consumo, geração de energia, abastecimento público, industrial, irrigação, dentre outros. O Brasil em particular possui seu sistema elétrico altamente dependente dos recursos hídricos, ou seja, altamente vulnerável a problemas hidroclimatológicos, como bem evidenciado na crise hídrica do ano de 2014 que impactou o sistema hidroenergético e sistemas de suprimento hídrico de muitos municípios na região Sudeste. O presente trabalho objetivou investigar os impactos desses períodos críticos, por meio de simulações de anomalias futuras nas precipitações e, consequentemente, os impactos nas vazões e nas séries históricas de ENA (Energia Natural Afluente), analisando, assim, os riscos aos quais o SIN (Sistema Interligado Nacional de Energia Elétrica) está exposto. Os resultados mostram que para questão energética estes impactos são importantes e consideráveis, porém para outros usos de água, sejam estes conflitantes com a geração de energia ou não, os efeitos podem ser ainda mais severos, principalmente nas porções Norte e Nordeste do país / Abstract: The hydroclimatological variability in the form of drought or temporal anomalies in volumetric rainfall is a problem faced by many countries and regions in the world. These phenomenon affect all the water's uses, these are: for consumption, power generation, drinking, industry, irrigation, and others. In the Brazil particular case this electrical system is highly dependent on water, and this is highly vulnerable to hydroclimatologicals problems, as well evidenced in the water crisis of 2014 which affected the hydroelectric system and water supply systems in many municipalities in the Southeast. This study aimed to investigate the impact of these critical periods, through simulations of future anomalies in rainfall and hence the impact on flows and the historical series of ENA (Natural Affluente Energy), analyzing the risks with the SIN (National Interconnected Electric Power System) are exposed. The results show that for energy issue these impacts are important and significant, but for other water uses, whether conflicting with the generation of energy or not, the effects can be even more severe, especially in the North and Northeast parts of the country / Doutorado / Recursos Hidricos, Energeticos e Ambientais / Doutor em Engenharia Civil
63

Oportunidades e alternativas para a mudança da matriz energética peruana : o papel do gás natural / Opportunities and alternatives for change of the Peru's energy matrix : the role of natural gas

Gonzales Palomino, Raul 20 August 2018 (has links)
Orientador: Silvia Azucena Nebra de Perez / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T12:24:18Z (GMT). No. of bitstreams: 1 GonzalesPalomino_Raul_D.pdf: 6830168 bytes, checksum: 3e74d7ae4f032a2a7aa3b78e9358cca1 (MD5) Previous issue date: 2012 / Resumo: Nos últimos anos, várias discussões e análises sobre um maior uso de gás natural no Peru foram realizadas. No início de 2011, durante os debates presidenciais, este era um item da agenda, e a priorização do desenvolvimento do mercado interno de gás, em vez de sua exportação foi o tema central. A presente tese analisa as alternativas de uso do gás natural nos setores de transporte, residencial, terciário, industrial de grande porte e de geração elétrica no Peru, assim como avalia o impacto da sua penetração na substituição de combustíveis derivados do petróleo e a possibilidade de produção de eletricidade através da cogeração. Para tanto, foram efetuadas uma análise da matriz energética peruana, uma revisão das reservas e infraestrutura da indústria do gás natural, para uma avaliação complementar e como ferramenta de comparação foram calculados os indicadores de sustentabilidade energética do País. Além disso, foi realizada uma revisão das metodologias existentes e empregadas para este tipo de estudo, além de definidos a abrangência e os cenários deste trabalho. Dos cenários avaliados, o tendencial- moderado seria o mais provável de acontecer e se viabilizar. Este mostra que o uso do gás natural aumentará de 3.280 Mm3, em 2008, para 6.295 Mm3, em 2020, melhorando, assim, a distribuição de sua utilização nos diferentes setores analisados, não sendo utilizado majoritariamente no setor de geração elétrica, como ocorre na atualidade. Por outro lado, a maior penetração deste energético permitirá substituir combustíveis derivados do petróleo, como o óleo Diesel, óleo combustível, gasolina e GLP, e, consequentemente, reduzir as emissões de dióxido de carbono. Os resultados mostram a existência de reservas para um maior desenvolvimento do mercado interno do gás natural no curto e médio prazo, mas, no futuro, é necessário continuar avaliando as reservas e o uso do gás (incluindo a exportação), considerando a garantia de seu fornecimento no longo prazo, descobertas de reservas e novos projetos para sua utilização / Abstract: In recent years there have been several discussions and analysis on a greater use of natural gas in Peru. This was part of the agenda during the presidential debates in early 2011. During these debates, the importance of developing a domestic demand for natural gas rather than gas exports was the central theme of discussion. This thesis analyzes the alternative for the use of natural gas in sectors such as transportation, residential, commercial, large-sized industry and power generation in Peru. Moreover, it evaluates the impact of its penetration as a replacement for oil products and the possibility of production of electricity through cogeneration. For this, an analysis on the Peru's energy matrix was conducted. Also, the current reserves and infrastructure of the natural gas industry were shown and additionally as a tool for comparison were calculated energy indicators for sustainable development in the country. In addition, a review of existing and used methodologies for this type of study were performed, and the scope and scenarios of this work were defined. The moderate trend scenario would be more feasible and likely to occur in comparison to all the scenarios evaluated in this study. This scenario shows that the use of natural gas will increase from 3.280 Mm3 in 2008 to 6295 Mm3 in 2020, which will improve the distribution of it in the different sectors that were analyzed, and reduce its use in the power generation sector where natural gas is mainly being utilized as of today. The greater penetration of natural gas would reduce the use of oil products such as Diesel oil, residual oil, gasoline and LPG, and thereby reduce CO2 emissions. The results show the existence of reserves for further development in the domestic gas market in the short and medium term, but in the future it will be necessary to continue evaluating the reserves and consumption of the natural gas in order to guarantee its supply for the long term, the discovery of new reserves, and the development of new projects for its use / Doutorado / Planejamento de Sistemas Energeticos / Doutor em Planejamento de Sistemas Energéticos
64

La réglementation internationale du commerce de matières premières : l'exemple des ressources énergétiques / No English title available

Grigorova, Zhenya 25 June 2016 (has links)
Les désaccords interétatiques concernant le commerce de ressources énergétiques évoluent au gré des découvertes de gisements et des crises énergétiques. La juridicisation des relations internationales fait pénétrer ces désaccords dans le monde du droit. Cette tendance se manifeste par la multiplication des différends en la matière portés à l’attention de juridictions nationales, régionales et internationales. Ces différends mettent en évidence non seulement l’importance exceptionnelle qu’a le secteur énergétique pour l’existence même des États, mais aussi l’actualité constante du débat sur les règles encadrant les activités économiques dans ce secteur. En tout état de cause, sa dimension internationale prend largement le pas sur la dimension interne. L’interdépendance est en effet inéluctable en la matière : même s’il recherche l’indépendance énergétique, tout État est tributaire des flux énergétiques mondiaux et des prix internationaux des ressources énergétiques. Polymorphe par nature, le débat sur la réglementation internationale du secteur énergétique se resserre aujourd’hui sur le domaine des relations commerciales internationales. Le poids que ce secteur a dans l’économie de chaque État rend la coopération en la matière inévitable. Or, depuis sa création en 1995, c’est l’Organisation mondiale du commerce qui est l’outil principal d’encadrement du commerce international. L’important saut que marquent l’entrée en vigueur de l’Accord instituant l’OMC et l’adhésion quasi-universelle à cette organisation internationale attire logiquement les éventuels désaccords vers ce cadre réglementaire. Le débat acquière ainsi une nature juridique, tout en gardant ses tournures politiques.C’est précisément au confluent entre les spécificités entourant le commerce de ressources énergétiques et celles inhérentes au droit de l’OMC que se situe l’objet de la présente étude. Le monde énergétique est en constante évolution, influencé par le développement de nouvelles technologies, de nouvelles ressources8, de nouvelles préoccupations politiques (qui souvent font ressurgir d’anciens débats9). De son côté, après vingt ans d’existence, l’OMC est sortie de sa phase d’adolescence10, pour revendiquer et surtout défendre sa place sur la scène de la gouvernance mondiale. Le droit qu’elle encadre et qu’elle génère est appelé (et de plus en plus sollicité) à jouer un rôle dans la réglementation du commerce de ressources énergétiques. Avant de préciser cette problématique pour y situer la principale thèse soutenue dans le présent travail (III), le sujet appelle des précisions préalables quant à la détermination du domaine analysé, le commerce international de ressources énergétiques (I), et de la perspective adoptée, la reconstruction intellectuelle du cadre normatif qui réglemente le commerce international dans le secteur (II). / No English summary available.
65

The role of Azerbaijan in the context of EU energy security / The role of Azerbaijan in the context of EU energy security

Aliyev, Abdul January 2017 (has links)
The thesis deals with the issue of energy security in the European Union, and the role played by Azerbaijan in the provision of the EU's energy independence and long-term stability. The author investigates the current issues of the European Union's energy policy, and the main threats impairing the EU's energy independence. Countries of the Caspian Basin, and particularly Azerbaijan, are investigated as the main alternative suppliers of energy resources for the European Union to increase its energy security. The author justifies and forecasts the future development of the EU-Azerbaijani relations in the energy sector taking into account the current policies implemented by the European Union in the field of energy security.
66

Podnikatelský plán - malá vodní elektrárna / Business plan - hydro power station

Možná, Markéta January 2009 (has links)
Subject of this graduation thesis is an assessment of business plan for hydro power station conctruction. The purpose of this thesis is to elaborate feasibility study to fullfill application form for financial support from the EU Structural Funds. First theoretical chapter is focused on conception of renewable resources, hydraolic power, qualification of process preparation and realization of business plan. Second chapter is an elaboration of chosen business plan. The structure of this business plan follows requirements specified by current EKO-ENERGIE aid program appell. In conclusion the thesis analyses and comments the obtained results given by the elaborated feasibility study.
67

Model Predictive Control for Resilient Operation of Hybrid Microgrids

January 2019 (has links)
abstract: This dissertation develops advanced controls for distributed energy systems and evaluates performance on technical and economic benefits. Microgrids and thermal systems are of primary focus with applications shown for residential, commercial, and military applications that have differing equipment, rate structures, and objectives. Controls development for residential energy heating and cooling systems implement adaptive precooling strategies and thermal energy storage, with comparisons made of each approach separately and then together with precooling and thermal energy storage. Case studies show on-peak demand and annual energy related expenses can be reduced by up to 75.6% and 23.5%, respectively, for a Building America B10 Benchmark home in Phoenix Arizona, Los Angeles California, and Kona Hawaii. Microgrids for commercial applications follow after with increased complexity. Three control methods are developed and compared including a baseline logic-based control, model predictive control, and model predictive control with ancillary service control algorithms. Case studies show that a microgrid consisting of 326 kW solar PV, 634 kW/ 634 kWh battery, and a 350 kW diesel generator can reduce on-peak demand and annual energy related expenses by 82.2% and 44.1%, respectively. Findings also show that employing a model predictive control algorithm with ancillary services can reduce operating expenses by 23.5% when compared to a logic-based algorithm. Microgrid evaluation continues with an investigation of off-grid operation and resilience for military applications. A statistical model is developed to evaluate the survivability (i.e. probability to meet critical load during an islanding event) to serve critical load out to 7 days of grid outage. Case studies compare the resilience of a generator-only microgrid consisting of 5,250 kW in generators and hybrid microgrid consisting of 2,250 kW generators, 3,450 kW / 13,800 kWh storage, and 16,479 kW solar photovoltaics. Findings show that the hybrid microgrid improves survivability by 10.0% and decreases fuel consumption by 47.8% over a 168-hour islanding event when compared to a generator-only microgrid under nominal conditions. Findings in this dissertation can increase the adoption of reliable, low cost, and low carbon distributed energy systems by improving the operational capabilities and economic benefits to a variety of customers and utilities. / Dissertation/Thesis / Doctoral Dissertation Engineering 2019
68

A Qualitative Study of EMaaS Performance in California Schools

January 2020 (has links)
abstract: In recent years, many school districts, community colleges, and universities in California have implemented energy management-as-a-service (EMaaS). The purpose of this study was to analyzes how EMaaS has been realized in California schools, including how performance expectations and service guarantees have been met, how value is created and captured, and which trends are emerging in the pay-for-performance models. This study used a qualitative research design to identify patterns in the collected data and allow theories to be drawn from the emergent categories and themes. Ten in-depth interviews were conducted with a diverse pool of facility managers, energy practitioners, superintendents, and associate superintendents working with EMaaS. Four themes emerged (1) peak shaving overperformance, (2) low risk/reward, (3) performance exactly as expected, and (4) hope in future flexibility. This study reveals medium to high levels of performance satisfaction from the customers of cloud-enabled and battery-based EMaaS in California schools. Value has been captured primarily through peak shaving and intelligent bill management. Large campuses with higher peaks are especially good at delivering energy savings, and in some instances without pairing batteries and solar. Where demand response participation is permitted by the utility companies, the quality of demand response performance is mixed, with performance being exactly as expected to slightly less than expected. The EMaaS business model is positioned to help California schools implement and achieve many of their future sustainability goals in a cost-effective way. / Dissertation/Thesis / Masters Thesis Construction Management 2020
69

ENERGY ANALYSIS OF A SOLAR BLIND CONCEPT INTEGRATED WITH ENERGY STORAGE SYSTEM

Niaparast, Shervin January 2013 (has links)
The use of an attached sunspace is one of the most popular passive solar heating techniques. One of the main drawbacks of the sunspace is getting over heated by the sun energy during the hot season of the year. Even in northern climates overheating could be problematic and there is a considerable cooling demand. Shading is one of the most efficient and cost effective strategies to avoid overheating due to the high irradiation especially in the summer. Another strategy is using ventilation system to remove the excess heat inside the sunspace. However this rejected energy can be captured and stored for future energy demands of the sunspace itself or nearby buildings. Therefore the Solar blind system has been considered here for the shielding purpose in order to reduce the cooling demand. By considering the PV/T panels as the solar blind, the blocked solar energy will be collected and stored for covering part of the heating demand and the domestic hot water supplies of the adjacent building.  From a modeling point of view, the sunspace can be considered as a small-scale closed greenhouse. In the closed greenhouse concept, available excess heat is indeed utilized in order to supply the heating demand of the greenhouse itself as well as neighboring buildings. The energy captured by PV/T collectors and the excess heat from the sunspace then will be stored in a thermal energy storage system to cover the daily and seasonal energy demand of the attached building. In the present study, a residential building with an attached sunspace with height, length and width of 3, 12 and 3.5 meters respectively has been assumed located in two different locations, Stockholm and Rome. Simulations have been run for the Solar blind system integrated with a short-term and a long-term TES systems during a year to investigate the influence of the sunspace equipped with a PV/T Solar blind on the thermal behavior of the adjacent building. The simulated results show that the Solar blind system can be an appropriate and effective solution for avoiding overheating problems in sunspace and simultaneously produce and store significant amount of thermal energy and electricity power which leads to saving considerable amount of money during a year.
70

Rural electrification using renewable energy resources - Case Study of Rayal, Nepal : Minor Field Study

Beck, Madeleine, Schött, Cecilia January 2013 (has links)
This study has been conducted as a Minor Field Study (MFS) and focuses on the electrification process of Rayal, a remote village in the Far Western Development Region of Nepal. The purpose of the study was to investigate the possibilities of providing electricity based on renewable energy resources to Rayal, both from a technical and a socio-economical point of view. Preliminary research in Sweden was complemented by a field study in Rayal between February and April 2013. Wind power, solar power and micro hydro power were investigated as potential sources of energy. Wind power was considered as unsuitable, due to the low wind speeds in the village as well as poor infrastructure in the country. Solar power and micro hydro power were both calculated based on three different demand scenarios. The results indicate that, depending on the demand and paymentability of the villagers, both solar and micro hydro power could be considered as good options. Solar power is, however, only economically feasible for covering the basic needs of lighting. At higher loads micro hydro power is more economically viable. Excess electricity could be utilized by community facilities, to improve education and health. Alternatively, it could be used to power electrical agricultural equipment which could improve productivity and hence stimulate economic growth in the village. / Denna studie har utförts i form av en Minor Field Study (MFS) och fokuserar på hur en elektrifiering skulle kunna ske av Rayal, en avlägsen by i Far Western Development Region i Nepal. Syftet med studien är att undersöka vilka möjligheter som finns för att elektrifiera Rayal med hjälp av förnyelsebara energikällor, både ur ett tekniskt och från ett socio-ekonomiskt perspektiv. De tre olika teknikerna som har undersökts är vindkraft, solkraft samt småskalig vattenkraft. Vindkraft har uteslutits som lämpligt alternativ, på grund av för låga vindhastigheter i byn, samt bristande infrastruktur i Nepal. Solkraft och vattenkraft har undersökts utifrån tre olika behovs-scenarion. Resultaten visar att, beroende på efterfrågan och betalningsförmågan hos byborna, kan både sol och småskalig vattenkraft betraktas som lämpliga alternativ. Solkraft är dock endast ekonomiskt försvarbart vid mindre projekt, som täcker det grundläggande behovet av belysning. Vid ett större behov är småskalig vattenkraft en mer ekonomisk lösning. Detta ökade behov skulle till exempel kunna vara samhällsförbättrande anläggningar, för att höja utbildnings- och hälsonivån. Ett annat ökat behov skulle kunna vara elektriskt drivna jordbruksmaskiner för att förbättra produktiviteten och därigenom stimulera den ekonomiska tillväxten i byn.

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