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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

The Impact of OPEC's Economic Policy on European Energy Trade and Security

Týrala, Tomáš January 2011 (has links)
No description available.
2

Some aspects of modelling and control of automotive power systems

Kuriger, I. F. January 1985 (has links)
No description available.
3

Renewable energy and the availability of water in a future South Africa

Jordaan, G. January 2013 (has links)
Published Article / The world is increasingly being misused by its inhabitants by the wasteful manner that its resources are utilized and the amount of pollution that is generated in the environment. This practice is unsustainable and it is incumbent on the present generation of decision-makers to rectify this phenomenon if our descendants are to have an opportunity to live life in the same manner as we do. Special emphasis should be placed on a reduction in the amount of air pollution that is created by electrical power generating plants, as well as the manner in which potable water is utilized and wasted. In this article the local situation with respect to the generation and use of electrical energy and water is discussed. It is encouraging to see that the National Government is taking strong steps to address these problems. Yet, it might not have the required ability to finance these efforts fully.
4

Proposta de conservação de energia elétrica aplicada ao campus de São Carlos - USP / not available

Pereira, Alexandre Cristiano 22 April 1998 (has links)
Atualmente, diante dos possíveis riscos de falta no fornecimento de energia elétrica no Brasil, surge a necessidade de se educar os consumidores a utilizar corretamente a energia elétrica, pois é mais barato conservar energia do que produzi-Ia. Na busca de solucionar a má utilização da energia elétrica em um campus universitário, levantam-se as características da instalação existente por meio de um equipamento registrador/medidor de grandezas elétricas. De posse destes dados, descrevem-se os problemas de consumo e de dimensionamento dos equipamentos encontrados nas instalações internas, a fim de se apontarem soluções técnicas viáveis para que se possa ter o uso racional de energia elétrica, as quais também poderão ser utilizadas em quaisquer outros centros consumidores. Além disto, abordam-se aspectos relativos ao gerenciamento das instalações existentes, visando-se o correto uso da energia elétrica, independentemente das condições em que se encontram as instalações. E dentro do possível, analisam-se as medidas sugeridas, o que demonstra a viabilidade das mudanças, frente à manutenção dos gastos existentes. / Due to the current possible risks to electric energy supply in Brazil, there is the need of making the consumers aware of how to use electric energy correctly, because it is cheaper to conserve energy than to produce it. Seeking to correct the use of electric energy in a university campus, characteristics of the existent installation were researched by means of recording/measuring equipment of electric variables. With this data provided is described the problems of consumption and use of the equipment found in the intemal facilities, with the purpose of aiming at viable technical solutions as to the rational use of electric energy, not only locally but in any other consumer centers. Furthermore, some aspects related to the management of the existent facilities were approached with a view to using electric energy correctly, independently of the conditions which of facilities are met. Suggested measures are analyzed for the sake of evaluating the viability the proposed changes, with regard to the maintenance of the existent expenses.
5

Proposta de conservação de energia elétrica aplicada ao campus de São Carlos - USP / not available

Alexandre Cristiano Pereira 22 April 1998 (has links)
Atualmente, diante dos possíveis riscos de falta no fornecimento de energia elétrica no Brasil, surge a necessidade de se educar os consumidores a utilizar corretamente a energia elétrica, pois é mais barato conservar energia do que produzi-Ia. Na busca de solucionar a má utilização da energia elétrica em um campus universitário, levantam-se as características da instalação existente por meio de um equipamento registrador/medidor de grandezas elétricas. De posse destes dados, descrevem-se os problemas de consumo e de dimensionamento dos equipamentos encontrados nas instalações internas, a fim de se apontarem soluções técnicas viáveis para que se possa ter o uso racional de energia elétrica, as quais também poderão ser utilizadas em quaisquer outros centros consumidores. Além disto, abordam-se aspectos relativos ao gerenciamento das instalações existentes, visando-se o correto uso da energia elétrica, independentemente das condições em que se encontram as instalações. E dentro do possível, analisam-se as medidas sugeridas, o que demonstra a viabilidade das mudanças, frente à manutenção dos gastos existentes. / Due to the current possible risks to electric energy supply in Brazil, there is the need of making the consumers aware of how to use electric energy correctly, because it is cheaper to conserve energy than to produce it. Seeking to correct the use of electric energy in a university campus, characteristics of the existent installation were researched by means of recording/measuring equipment of electric variables. With this data provided is described the problems of consumption and use of the equipment found in the intemal facilities, with the purpose of aiming at viable technical solutions as to the rational use of electric energy, not only locally but in any other consumer centers. Furthermore, some aspects related to the management of the existent facilities were approached with a view to using electric energy correctly, independently of the conditions which of facilities are met. Suggested measures are analyzed for the sake of evaluating the viability the proposed changes, with regard to the maintenance of the existent expenses.
6

Combate, prevenção e otimização das perdas comerciais de energia elétrica. / Combat, prevention and optimization of non technical losses of electric power distribution.

Penin, Carlos Alexandre de Sousa 28 April 2008 (has links)
As perdas de energia elétrica devidas a furtos e fraudes, também chamadas de Perdas Não-Técnicas (PNT) ou Perdas Comerciais, têm sido matéria prioritária das empresas concessionárias de distribuição de energia elétrica, bem como dos órgãos reguladores, tanto pelo seu crescimento nos últimos anos quanto pelo seu impacto no sistema elétrico brasileiro. As formas de fraude são as mais variadas possíveis, o que gera enormes dificuldades para as concessionárias. Este trabalho tem como objetivo o estudo do problema das PNT utilizando-se de uma abordagem multidisciplinar, que analisa a experiência tanto de concessionárias no Brasil como no exterior. O trabalho discute as melhores práticas para mitigação das mesmas e propõe melhorias nos processos de combate e de prevenção, e nos procedimentos legais para recuperação de receitas, apoiados sobre uma cuidadosa contextualização regulatória. Chamase a atenção para a diversidade sócio-econômica nacional, compara-se com diversos exemplos internacionais, e propõe-se identificar os aspectos mais relevantes a serem considerados na regulação sobre o tema, discutindo procedimentos e metodologias para o equacionamento do montante de recursos a serem aplicados pelas companhias distribuidoras para a adequada redução dessas perdas de energia. Observa-se que grande parte das PNT tem origem em questões de cunho social. O Estado pode e deve estabelecer políticas para resolver tais questões, possibilitando a universalização do acesso e subsidiando o fornecimento de energia elétrica. Não fez parte dessa pesquisa discutir se estes instrumentos são suficientes ou devem ser aprimorados, mas sim analisar amplamente a questão das PNT com base nos condicionantes regulatórios atuais, que obrigam as concessionárias a reduzir estas perdas visando entre outros a modicidade tarifária dos consumidores regulares. / The electric power losses due to thefts and frauds, also called Non technical Losses (NTL), have been priority matter for concessionary companies of electric power distribution, as well as for government regulatory agencies, not only due to rapid growth over the past years but also due to its impact on Brazilian electrical system. There is a wide range of possible types and methods of frauds, causing enormous difficulties to licensed companies. The objective of this work is to study the problem of NTL using a wide approach, analyze the experience of dealerships in Brazil and abroad, discuss the best practices for mitigation of those losses and propose improvements in the combat and prevention processes, and the legal procedures for recovery of incomes, leaning on a careful regulatory context. This study draws attention to Brazil\'s socioeconomic diversity, comparing it to various international examples, and intends to identify the most relevant aspects that must be considered on the theme, discussing procedures and methodologies for the equation of the amount of resources to be applied by distributing companies to achieve the appropriate reduction of NTL. A large part of the commercial losses has its origin in issues of social stamp. The State owes and can establish policies to solve such issues, making possible the access to electric power supply for all consumers. It was not part of this research to discuss if these instruments are enough, but to analyze the issue of the commercial losses thoroughly based in the regulatory policies that push dealerships to reduce NTL objecting reasonable regular consumers\' tariff.
7

Combate, prevenção e otimização das perdas comerciais de energia elétrica. / Combat, prevention and optimization of non technical losses of electric power distribution.

Carlos Alexandre de Sousa Penin 28 April 2008 (has links)
As perdas de energia elétrica devidas a furtos e fraudes, também chamadas de Perdas Não-Técnicas (PNT) ou Perdas Comerciais, têm sido matéria prioritária das empresas concessionárias de distribuição de energia elétrica, bem como dos órgãos reguladores, tanto pelo seu crescimento nos últimos anos quanto pelo seu impacto no sistema elétrico brasileiro. As formas de fraude são as mais variadas possíveis, o que gera enormes dificuldades para as concessionárias. Este trabalho tem como objetivo o estudo do problema das PNT utilizando-se de uma abordagem multidisciplinar, que analisa a experiência tanto de concessionárias no Brasil como no exterior. O trabalho discute as melhores práticas para mitigação das mesmas e propõe melhorias nos processos de combate e de prevenção, e nos procedimentos legais para recuperação de receitas, apoiados sobre uma cuidadosa contextualização regulatória. Chamase a atenção para a diversidade sócio-econômica nacional, compara-se com diversos exemplos internacionais, e propõe-se identificar os aspectos mais relevantes a serem considerados na regulação sobre o tema, discutindo procedimentos e metodologias para o equacionamento do montante de recursos a serem aplicados pelas companhias distribuidoras para a adequada redução dessas perdas de energia. Observa-se que grande parte das PNT tem origem em questões de cunho social. O Estado pode e deve estabelecer políticas para resolver tais questões, possibilitando a universalização do acesso e subsidiando o fornecimento de energia elétrica. Não fez parte dessa pesquisa discutir se estes instrumentos são suficientes ou devem ser aprimorados, mas sim analisar amplamente a questão das PNT com base nos condicionantes regulatórios atuais, que obrigam as concessionárias a reduzir estas perdas visando entre outros a modicidade tarifária dos consumidores regulares. / The electric power losses due to thefts and frauds, also called Non technical Losses (NTL), have been priority matter for concessionary companies of electric power distribution, as well as for government regulatory agencies, not only due to rapid growth over the past years but also due to its impact on Brazilian electrical system. There is a wide range of possible types and methods of frauds, causing enormous difficulties to licensed companies. The objective of this work is to study the problem of NTL using a wide approach, analyze the experience of dealerships in Brazil and abroad, discuss the best practices for mitigation of those losses and propose improvements in the combat and prevention processes, and the legal procedures for recovery of incomes, leaning on a careful regulatory context. This study draws attention to Brazil\'s socioeconomic diversity, comparing it to various international examples, and intends to identify the most relevant aspects that must be considered on the theme, discussing procedures and methodologies for the equation of the amount of resources to be applied by distributing companies to achieve the appropriate reduction of NTL. A large part of the commercial losses has its origin in issues of social stamp. The State owes and can establish policies to solve such issues, making possible the access to electric power supply for all consumers. It was not part of this research to discuss if these instruments are enough, but to analyze the issue of the commercial losses thoroughly based in the regulatory policies that push dealerships to reduce NTL objecting reasonable regular consumers\' tariff.
8

Understanding energy-economy models: survey evidence from model users and developers in Canada

Craig, Kira 06 August 2021 (has links)
Energy-economy models are important tools used by policy-makers and researchers to design effective climate policy. However, there has been limited research that compares models against consistent characteristics to understand their impacts on climate policy projections. This can make it difficult for policy-makers to identify suitable models for their specific policy questions and develop effective climate policies. A web-based survey of energy-economy model users and developers in Canada’s public, private, and non-profit sectors (n=14) was conducted to systematically compare seventeen models against a framework of seven characteristics: technology characteristics, micro-, and macro-economic characteristics, policy representations, treatment of uncertainty, high-resolution spatial and temporal representations, and data transparency. It was found that for the most part, models represent technology, micro-, and macro-economic characteristics according to the classic typology of bottom-up, top-down, and hybrid models. However, our findings show that several modelling evolutions have occurred. Some top-down models can explicitly represent technologies and some bottom-up models incorporate microeconomic characteristics. Models differ in the types of policies they can simulate, sometimes underrepresenting performance regulations, government procurement, and research and development programs. All models incorporate at least one type of uncertainty analysis, models infrequently have high-resolution spatial and/or temporal representations, and most models lack publicly accessible methodological documents. Implications for researchers and policy-makers that use energy-economy models and/or develop policies are discussed. / Graduate
9

Modellgestützte Wirtschaftlichkeitsbewertung von Betriebskonzepten für Elektrolyseure in einem Energiesystem mit hohen Anteilen erneuerbarer Energien

Michaelis, Julia 06 October 2018 (has links)
Um die internationalen Klimaschutzziele zu erreichen, ist es notwendig, Strom verstärkt aus erneuerbaren Energien zu gewinnen. Gleichzeitig bedarf es flexibler Verbraucher zum Ausgleich der schwankenden Stromeinspeisung. Da nicht alle Anwendungen vollständig auf die direkte Nutzung von Strom umgestellt werden können, werden weitere Energieträger als Speichermedium benötigt. Wasserstoff, der über die flexibel steuerbare Elektrolyse aus Strom und Wasser gewonnen werden kann, ist ein vielfältig nutzbarer Energieträger, z.B. für die chemische Industrie oder für Brennstoffzellenfahrzeuge. Heute ist der Einsatz des Elektrolyseurs noch nicht wirtschaftlich, da die Wasserstoffgestehungskosten über denen konkurrierender Verfahren liegen. Bei geänderten Rahmenbedingungen und fortschreitender Entwicklung der Elektrolysetechnologie kann sich dies jedoch ändern, weshalb sich die Frage stellt: Kann ein Elektrolyseur im deutschen Energiesystem mit hohen Anteilen erneuerbarer Energien zukünftig wirtschaftlich betrieben werden? Zur Beantwortung der Fragestellung wird zunächst auf Stromhandelsplätze und die aktuelle Marktsituation für flexible Technologien am Strommarkt eingegangen und Entwicklungen im Bereich der Wasserstoffproduktion und -nachfrage werden vorgestellt. Um zukünftige Strombörsenpreise für verschiedene Szenarien zu bestimmen, wird anschließend ein fundamentales Simulationsmodell erstellt. Zwei Handelsplätze, die für den Elektrolyseurbetrieb von Bedeutung sind, stehen im Fokus: der Spotmarkt für den kurzfristigen Stromhandel und der Regelleistungsmarkt für die Vermarktung flexibler Lasten. Für den Regelleistungsmarkt werden Preise anhand eines Opportunitätskostenansatzes bestimmt. Die simulierten Marktpreise werden als Eingangsdaten für ein Optimierungsmodell verwendet, das den Deckungsbeitrag für den Betrieb eines Elektrolyseurs unter Berücksichtigung technischer Restriktionen maximiert. Verschiedene Betriebskonzepte werden hierbei untersucht, die den direkten Absatz von Wasserstoff, dessen Rückverstromung oder auch die Regelleistungsvorhaltung berücksichtigen. Anhand der erzielten Erlöse und Kosten lassen sich die Konzepte bewerten und die Forschungsfrage beantworten. Anhand von drei aus der Literatur ausgewählten Szenarien werden Entwicklungspfade des Energiesystems sowie verschiedene Ausprägungen techno-ökonomischer Parameter des Elektrolyseurs bis zum Jahr 2050 festgelegt. Die Szenarien unterscheiden sich u.a. hinsichtlich des Ausbaus erneuerbarer Energien und der Energieträgerpreise. Es zeigt sich, dass ein wirtschaftlicher Betrieb, wenn überhaupt, erst langfristig, d.h. voraussichtlich nach dem Jahr 2030, möglich ist. Dafür muss die Investition in den Elektrolyseur deutlich sinken und der Wirkungsgrad steigen oder die energiewirtschaftlichen Rahmenbedingungen müssen eine hohe Auslastung mit niedrigen Strombezugskosten ermöglichen. Als wirtschaftlich gilt der Elektrolyseurbetrieb, wenn Wasserstoff kostengünstiger hergestellt werden kann als mit konventionellen Verfahren. Dies gelingt v.a. dann, wenn zusätzlich Regelleistung vorgehalten wird. Die Rückverstromung von Wasserstoff ist in den meisten Fällen nicht rentabel. Soll die Elektrolyse früher Einsatz finden, da sie möglicherweise für das Erreichen der Klimaschutzziele unumgänglich wird, bedarf es hierfür gezielter Anreize.:1 Einleitung 1 1.1 Ausgangslage und Problemstellung 1 1.2 Zielsetzung und Lösungsweg 5 2 Rahmenbedingungen im Stromsektor und in der Wasserstoffwirtschaft 9 2.1 Entwicklungen im Stromsektor 9 2.1.1 Flexibilitätsbedarf zur Integration erneuerbarer Energien 10 2.1.2 Ausgestaltung von Stromhandelsplätzen 16 2.1.3 Heutiges und zukünftiges Marktumfeld für Flexibilitätsoptionen 19 2.2 Entwicklungen im Bereich der Wasserstoffwirtschaft 24 2.2.1 Nutzung von Wasserstoff 25 2.2.2 Produktionsverfahren zur Bereitstellung von Wasserstoff 33 2.2.3 Techno-ökonomischer Vergleich ausgewählter Produktionsverfahren 37 2.3 Einsatz eines Elektrolyseurs am Strommarkt 45 3 Modellierung von Spotmarktpreisen 49 3.1 Funktionsweise des Spotmarktes 49 3.2 Vergleich und Auswahl eines Modellierungsansatzes für Spotmarktpreise 51 3.2.1 Anforderungen an die Modellierung 51 3.2.2 Bestehende Modellierungsansätze für Spotmarktpreise 53 3.2.3 Auswahl des Modellierungsansatzes 57 3.2.4 Ansätze zur Modellierung von Preisspitzen und negativen Preisen 59 3.3 Entwicklung eines Modellierungsansatzes für Spotmarktpreise 63 3.3.1 Aufbau des Fundamentalmodells 63 3.3.2 Optimierung des Speichereinsatzes 69 3.3.3 Regime-Switching-Ansatz zur Modellierung von Preisspitzen und negativen Preisen 73 3.3.4 Zusammenfassung des Modellierungsansatzes 79 3.4 Modellvalidierung anhand historischer Daten 81 3.4.1 Eingangsdaten 81 3.4.2 Validierung der simulierten Spotmarktpreise 83 3.4.3 Validierung der simulierten Zusammensetzung der Stromerzeugung 87 3.4.4 Validierung der simulierten CO2-Emissionen 88 3.4.5 Schlussfolgerungen aus der Validierung 89 4 Modellierung von Sekundärregelleistungspreisen 91 4.1 Ausgestaltung des Regelleistungsmarktes 91 4.1.1 Regulatorischer Rahmen 92 4.1.2 Bedarf an Regelleistung 95 4.1.3 Anbieter von Regelleistung 96 4.1.4 Teilnahme eines Elektrolyseurs am Regelleistungsmarkt 97 4.2 Modellierungsansätze für Regelleistungspreise 99 4.2.1 Anforderungen an die Modellierung 100 4.2.2 Bestehende Modellierungsansätze 100 4.2.3 Auswahl eines Modellierungsansatzes 103 4.2.4 Berechnung der Opportunitätskosten für Erzeugungs- und Nachfrageeinheiten 104 4.2.5 Aufbau des Opportunitätskostenansatzes zur Ermittlung der Leistungspreise 109 4.3 Validierung des Opportunitätskostenansatzes anhand historischer Daten 110 4.4 Zusammenfassung des Modellierungsansatzes 114 5 Wirtschaftlichkeitsbewertung eines Elektrolyseurs im zukünftigen Stromsystem 117 5.1 Grundlegende Annahmen für die Wirtschaftlichkeitsberechnung 117 5.2 Energieszenarien für den Stromsektor 119 5.2.1 Energieszenarien ausgewählter Studien 120 5.2.2 Auswahl von Energieszenarien für die weitere Analyse 124 5.3 Entwicklung des Stromsektors in den gewählten Energieszenarien 129 5.3.1 Entwicklung am Spotmarkt 129 5.3.2 Entwicklung der Sekundärregelleistungspreise 134 5.4 Ergebnisse der Wirtschaftlichkeitsbewertung 136 5.4.1 Wasserstoffgestehungskosten des Elektrolyseurs in den Szenarien 137 5.4.2 Zielwerte für techno-ökonomische Parameter des Elektrolyseurs 143 5.4.3 Bestimmung und Modellierung von Betriebskonzepten 148 5.4.4 Wirtschaftlichkeitsbewertung der Betriebskonzepte 152 5.4.5 Zusammenfassung der Wirtschaftlichkeitsbewertung 170 5.5 Einflussfaktoren auf die Wirtschaftlichkeit des Elektrolyseurbetriebs 172 6 Zusammenfassung, kritische Würdigung und Ausblick 175 6.1 Zusammenfassung und Schlussfolgerungen 175 6.2 Kritische Würdigung des verwendeten Ansatzes 182 6.3 Ausblick 184 / The international climate targets can only be achieved by generating more electricity using renewable energy sources. At the same time, flexible electricity consumers are needed to balance the fluctuating generation from renewables. As not all the electricity produced can be used directly, additional energy carriers are required as storage medium. Hydrogen that is produced by the flexible and controllable electrolysis of electricity and water is a versatile energy carrier, e.g. for the chemical industry or fuel cell electric vehicles. So far, this is not yet profitable, because the hydrogen production costs using electrolysis exceed those of competing methods. This could change under altered framework conditions and given the ongoing advances in electrolysis technology, which begs the question: Could hydrogen production using electrolysis be profitable in a future German energy system with high shares of renewable energies? To answer this question, electricity markets and the current market situation for flexible technologies are examined and developments in the field of hydrogen production and demand are presented. A fundamental simulation model is constructed to determine the future development of electricity market prices in different scenarios. The focus lies on two markets of relevance for operating electrolysers: the spot market for short-term electricity trading and the market for balancing power that allows the marketing of flexible loads. The prices on the market for balancing power are calculated using an approach based on opportunity costs. The simulated prices serve as input to an optimization model that maximizes the contribution margin of an electrolyser taking technical constraints into account. Different concepts are considered that include the direct sale of hydrogen, its reconversion into electricity as well as the provision of balancing power. The concepts are evaluated using the revenues and costs and the results used to answer the research question. Three scenarios selected from the literature depict different development pathways of the energy system as well as different values for the electrolyser’s techno-economic parameters up to the year 2050. The scenarios differ with regard to the deployment of renewable energy sources and the prices for energy carriers among other criteria. It becomes clear that profitable operation of electrolysers will, if at all, only be possible in the long term, probably from 2030 onwards. To achieve this, the electrolyser’s specific investment has to decrease and its efficiency has to increase or the framework conditions in the energy system must allow high full load hours of the electrolyser at low electricity costs. Operation is considered profitable if hydrogen can be produced via electrolysis at lower costs than conventional production methods. This is achieved in particular if the electrolyser is used to provide balancing power. Reconverting hydrogen into electricity is not profitable in most cases. However, electrolysis may become essential at an earlier point in time to meet climate targets. In this case, specific incentives are needed for its use.:1 Einleitung 1 1.1 Ausgangslage und Problemstellung 1 1.2 Zielsetzung und Lösungsweg 5 2 Rahmenbedingungen im Stromsektor und in der Wasserstoffwirtschaft 9 2.1 Entwicklungen im Stromsektor 9 2.1.1 Flexibilitätsbedarf zur Integration erneuerbarer Energien 10 2.1.2 Ausgestaltung von Stromhandelsplätzen 16 2.1.3 Heutiges und zukünftiges Marktumfeld für Flexibilitätsoptionen 19 2.2 Entwicklungen im Bereich der Wasserstoffwirtschaft 24 2.2.1 Nutzung von Wasserstoff 25 2.2.2 Produktionsverfahren zur Bereitstellung von Wasserstoff 33 2.2.3 Techno-ökonomischer Vergleich ausgewählter Produktionsverfahren 37 2.3 Einsatz eines Elektrolyseurs am Strommarkt 45 3 Modellierung von Spotmarktpreisen 49 3.1 Funktionsweise des Spotmarktes 49 3.2 Vergleich und Auswahl eines Modellierungsansatzes für Spotmarktpreise 51 3.2.1 Anforderungen an die Modellierung 51 3.2.2 Bestehende Modellierungsansätze für Spotmarktpreise 53 3.2.3 Auswahl des Modellierungsansatzes 57 3.2.4 Ansätze zur Modellierung von Preisspitzen und negativen Preisen 59 3.3 Entwicklung eines Modellierungsansatzes für Spotmarktpreise 63 3.3.1 Aufbau des Fundamentalmodells 63 3.3.2 Optimierung des Speichereinsatzes 69 3.3.3 Regime-Switching-Ansatz zur Modellierung von Preisspitzen und negativen Preisen 73 3.3.4 Zusammenfassung des Modellierungsansatzes 79 3.4 Modellvalidierung anhand historischer Daten 81 3.4.1 Eingangsdaten 81 3.4.2 Validierung der simulierten Spotmarktpreise 83 3.4.3 Validierung der simulierten Zusammensetzung der Stromerzeugung 87 3.4.4 Validierung der simulierten CO2-Emissionen 88 3.4.5 Schlussfolgerungen aus der Validierung 89 4 Modellierung von Sekundärregelleistungspreisen 91 4.1 Ausgestaltung des Regelleistungsmarktes 91 4.1.1 Regulatorischer Rahmen 92 4.1.2 Bedarf an Regelleistung 95 4.1.3 Anbieter von Regelleistung 96 4.1.4 Teilnahme eines Elektrolyseurs am Regelleistungsmarkt 97 4.2 Modellierungsansätze für Regelleistungspreise 99 4.2.1 Anforderungen an die Modellierung 100 4.2.2 Bestehende Modellierungsansätze 100 4.2.3 Auswahl eines Modellierungsansatzes 103 4.2.4 Berechnung der Opportunitätskosten für Erzeugungs- und Nachfrageeinheiten 104 4.2.5 Aufbau des Opportunitätskostenansatzes zur Ermittlung der Leistungspreise 109 4.3 Validierung des Opportunitätskostenansatzes anhand historischer Daten 110 4.4 Zusammenfassung des Modellierungsansatzes 114 5 Wirtschaftlichkeitsbewertung eines Elektrolyseurs im zukünftigen Stromsystem 117 5.1 Grundlegende Annahmen für die Wirtschaftlichkeitsberechnung 117 5.2 Energieszenarien für den Stromsektor 119 5.2.1 Energieszenarien ausgewählter Studien 120 5.2.2 Auswahl von Energieszenarien für die weitere Analyse 124 5.3 Entwicklung des Stromsektors in den gewählten Energieszenarien 129 5.3.1 Entwicklung am Spotmarkt 129 5.3.2 Entwicklung der Sekundärregelleistungspreise 134 5.4 Ergebnisse der Wirtschaftlichkeitsbewertung 136 5.4.1 Wasserstoffgestehungskosten des Elektrolyseurs in den Szenarien 137 5.4.2 Zielwerte für techno-ökonomische Parameter des Elektrolyseurs 143 5.4.3 Bestimmung und Modellierung von Betriebskonzepten 148 5.4.4 Wirtschaftlichkeitsbewertung der Betriebskonzepte 152 5.4.5 Zusammenfassung der Wirtschaftlichkeitsbewertung 170 5.5 Einflussfaktoren auf die Wirtschaftlichkeit des Elektrolyseurbetriebs 172 6 Zusammenfassung, kritische Würdigung und Ausblick 175 6.1 Zusammenfassung und Schlussfolgerungen 175 6.2 Kritische Würdigung des verwendeten Ansatzes 182 6.3 Ausblick 184
10

Economia de energia em irrigação por pivô central em função da melhoria na uniformidade da distribuição de água / Energy economy in a center pivot irrigation system according to the improvement in the uniformity of water distribution

Mendoza Castiblanco, Christian José 08 June 2009 (has links)
Em sistemas de irrigação por pivô central, a eficiência de aplicação em campo esta diretamente relacionada com a uniformidade de distribuição, afetando a economia de energia, num manejo adequado da irrigação. Foram utilizados dados de lâmina aplicada, lâmina média, vazão e comprimento de um pivô central, da região de Guaíra SP, através de uma avaliação de desempenho. Foram simuladas lâminas de água aplicadas para valores de 70%, 73%, 75%, 78%, 80%, 83%, 85%, 88%, 90%, 93% 95% e 98% do coeficiente de uniformidade de Christiansen (CUC), mantendo-se constante o valor da lâmina média e conseqüentemente a vazão. As receitas líquidas obtidas com essas distribuições de água foram comparadas utilizando-se cinco preços do feijão: R$1,75, R$2,00, R$2,25, R$2,50, R$2,75, R$3,00 e R$3,25 kg-1e, de igual forma, para cinco custos por consumo da água: R$ 0,01, R$ 0,02, R$ 0,03, R$ 0,04, e R$ 0,05m-3. Os resultados foram analisados considerando-se irrigação total e suplementar de 50% e 75%, nos períodos seco e úmido. A partir dos dados obtidos nas simulações verificouse que os maiores coeficientes de uniformidade proporcionam maior receita líquida e maior economia de energia para os maiores preços do produto. As irrigações suplementares possibilitaram maiores lucros e maiores economia de energia, especialmente para irrigações realizadas no período úmido / In irrigation systems by center pivot, the efficiency of applying in field is directly related to distribution uniformity, influencing in energy saving inside an appropriate irrigation management program. Were used data from applied layer, average layer, flow, and central pivot length, from Guairá SP, determined by IDE (1989) by a performance assessment. By simulation of collected layers values of 70%, 73%, 75%, 78%, 80%, 83%, 85%, 88%, 90%, 93% 95% and 98% were obtained from the Christiansen (CUC) Uniformity Coefficiency, keeping constant the average layer value and consequently the same flow. The obtained net income from those water distributions were compared using five beans prices in Brazilian currency R$1,75, R$2,00, R$2,25, R$2,50, R$2,75, R$3,00 and R$3,25 kg-1 and the same way, for five water consume costs: R$ 0,01, R$ 0,02, R$ 0,03, R$ 0,04, and R$ 0,05m-3. The outcomes were analyzed considering the supplementary and total irrigation of 50% an 75% in humid and dry seasons. From obtained data by simulations were verified that the higher uniformity coefficiencies give higher liquid recipe and greater energy saving related to higher products prices. Supplementary irrigation gives the possibility of higher profit and greater energy saving, especially when made in the humid season

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