The objectives of this dissertation were to find a principal domain of promising and technologically feasible reactor physics characteristics for a multi-purpose, modular-sized, lead-cooled, fast neutron spectrum reactor fueled with an advanced uranium-transuranic-nitride fuel and to determine the principal limitations for the design of an autonomous long-term multi-purpose fast reactor (ALM-FR) within the principal reactor physics characteristic domain. The objectives were accomplished by producing a conceptual design for an ALM-FR and by analysis of the potential ALM-FR performance characteristics. The ALM-FR design developed in this dissertation is based on the concept of a secure transportable autonomous reactor for hydrogen production (STAR-H2) and represents further refinement of the STAR-H2 concept towards an economical, proliferation-resistant, sustainable, multi-purpose nuclear energy system. The development of the ALM-FR design has been performed considering this reactor within the frame of the concept of a self-consistent nuclear energy system (SCNES) that satisfies virtually all of the requirements for future nuclear energy systems: efficient energy production, safety, self-feeding, non-proliferation, and radionuclide burning. The analysis takes into consideration a wide range of reactor design aspects including selection of technologically feasible fuels and structural materials, core configuration optimization, dynamics and safety of long-term operation on one fuel loading, and nuclear material non-proliferation. Plutonium and higher actinides are considered as essential components of an advanced fuel that maintains long-term operation. Flexibility of the ALM-FR with respect to fuel compositions is demonstrated acknowledging the principal limitations of the long-term burning of plutonium and higher actinides. To ensure consistency and accuracy, the modeling has been performed using state-of-the-art computer codes developed at Argonne National Laboratory. As a result of the computational analysis performed in this work, the ALM-FR design provides for the possibility of continuous operation during about 40 years on one fuel loading containing mixture of depleted uranium with plutonium and higher actinides. All reactor physics characteristics of the ALM-FR are kept within technological limits ensuring safety of ultra-long autonomous operation. The results obtained provide for identification of physical features of the ALM-FR that significantly influence flexibility of the design and its applications. The special emphasis is given to existing limitations on the utilization of higher actinides as a fuel component.

After closure of Ignalina nuclear power plant its capacity is going to be replaced by large-scale Lithuania’s power plants burning imported fossil fuel. This can lead to high energy system dependency from foreign countries, supplying mostly gas, and to the increase of environmental pollution. Meanwhile, some of small Lithuanian district heating companies suffer from high heat prices and consumers debts. Heat prices for consumers in small districts are by approximately 30 % higher, than for consumers in large cities. Needed electricity capacity could be partially replaced and district heating prices could be reduced by introducing small-scale cogeneration. This report is dealing with cogeneration technologies, their advantages and drawbacks. The possibilities and obstacles for implementation of these technologies in Lithuania are examined. The benefits from introduction of these technologies versus condensing power plants are analyzed. These issues have been assessed by simulating combined heat and power production in selected district heating company. There is evaluated the impact of electricity prices on the economy of different scenarios and heat prices. Finally, the conclusions about the feasibility of cogeneration implementation and the sufficiency of support schemes are made.

Rising energy demand, fossil fuel costs, and greenhouse gas emissions have led to a growing interest in renewable energy integration. Remote communities, often accompanied by high energy costs and abundant renewable energy resources, are ideal cases for renewable energy integration. The Queen Charlotte Islands, also known as Haida Gwaii, are a remote archipelago off the northwest coast of British Columbia, Canada that relies heavily on diesel fuel for energy generation. An investigation is done into the potential for electricity generation using both tidal stream and wave energy in Haida Gwaii. A mixed integer optimization network model is developed in a Matlab and GAMS software environment, subject to set of system constraints including minimum operational levels and transmission capacities. The unit commitment and economic dispatch decisions are dynamically solved for four periods of 336 hours, representing the four annual seasons. Optimization results are used to develop an operational strategy simulation model, indicative of realistic operator behaviour. Results from both models find that the tidal stream energy resource in Haida Gwaii has a larger potential to reduce energy costs than wave energy; however, tidal steam energy is more difficult to integrate from a system operation point of view and, in the absence of storage, would only be practical at power penetration levels less than 20%.

A l'heure actuelle, l'industrie représente environ le tiers de la consommation énergétique et des émissions de CO2. Des opportunités substantielles existent pour faire face aux enjeux environnementaux et économiques, passant par l'efficacité énergétique en général et l'utilisation de l'énergie, en particulier dans les parcs industriels. Les Systèmes à Energie Distribuée (SED) correspondent en ce sens à une solution courante et prometteuse. Nous avons donc entrepris une démarche d'approche globale de site, incluant l'agrégation de l'ensemble des variables énergétiques, économiques, environnementales et managériales influentes dans une installation de ce type. Une mise en application sur une installation pilote et sa validation ont permis d'identifier les verrous scientifiques et techniques et de mesurer pertinence et efficacité des éléments et modes opératoires des systèmes en mode stationnaire. Cette étude offre une méthode d'utilisation coopérative des indicateurs des domaines impactés et ouvre également des perspectives sur des développements en mode dynamique à des fins d'aide à la conduite optimale. / Nowadays, industry accounts for about one third of energy consumption and CO2 emissions. Substantial opportunities exist to address environmental and economic challenges, including energy efficiency in general and the use of energy, especially in industrial parks. Distributed Energy Systems (DES) correspond in this sense to a common and promising solution. We have therefore undertaken a global site approach, including the aggregation of all influential energy, economic, environmental and managerial variables in an installation of this type. Implementation on a pilot plant and its validation have made it possible to identify the scientific and technical locks and to measure the relevance and efficiency of the elements and stationary operating modes of the systems. This study offers a method of cooperative use of the indicators of impacted domains and also opens perspectives on developments in dynamic mode for the purposes of optimum driving assistance.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Sustainability is becoming a major driving force in energy policy, leading to the development of different strategies and projects. Many of these strategies are related to the application of novel methodologies for selecting Renewable Energy Systems (RES) and energy storage systems. Electrical generation with biogas from municipal solid waste (MSW) is one of the main alternatives to concern all the conceptions of sustainability - social, economic and environmental constrains. The complexity of sustainability and energy planning makes the multicriteria analysis a valuable tool for the decision making process. The use of an effective methodology for RES selection a decision making process is essential to guarantee the adequate energy management of the biogas and the MSW landfill. This methodology must be able to balance positive and negative aspects, achieving an overall solution that best satisfies the management needs. It is essential to deal with several parameters and concern the decision maker (DM) interaction over the decision making process. By applying the DM preferences into the development of the methodology, it is possible to corroborate the methodology outcome. The presented thesis will therefore develop a novel methodology for selection of RES fuelled by biogas from MSW landfills. This methodology taking as basis fuzzy multi-rules and multi-sets to provide an accurate analysis of conflicting aspects - operational, economic, environmental, social, etc. These aspects are taken into account for each study case according to different perspectives adopted by the DMs. The novel arrangements developed in this work are the creation of a previous classification of the priority criteria, the application of meta-rules and how to structure the fuzzy rules construction. The proposed arrangements have the purpose of easing the understanding of the methodology, as well as improving the DM interaction over the decision making process achieving in this way a better solution. This work presents the application of the novel decision making process to select the most appropriate energy source fuelled by biogas from MSW, considering the Caturrita II landfill located at Santa Maria City, Brazil. In conclusion, it is important to emphasize that the novel software may be used in any energy system selection, for supplying or storage, according to the analysis of several criteria and perspectives for each regional circumstances, as well as particular management needs.. / A busca pelo desenvolvimento sustentável, em âmbitos sociais e ambientais, é um fator de extrema importância que incentiva a elaboração de várias pesquisas e projetos, como por exemplo, à aplicação de técnicas de gerenciamento e seleção de fontes alternativas renováveis de geração de energia. Dentre estas fontes, o aproveitamento energético do biogás resultante da decomposição de resíduos sólidos urbanos é um dos meios que propicia um desenvolvimento sustentável de forma mais completa. Para o devido aproveitamento de fontes alternativas renováveis, como a geração de energia elétrica e térmica a partir de resíduos sólidos urbanos, deve-se tomar como base métodos multicriteriais, considerando a existência de uma série de critérios para atender necessidades e interesses diversos quando se deseja selecionar tecnologias de geração e armazenamento de energia. A partir da utilização de métodos de ajuda a decisão é possível incorporar de forma clara as preferências dos agentes de decisão, obtendo como resposta final uma solução mais satisfatória e que pode ser corroborada através de validações heurísticas discussões dos resultados junto aos agentes de decisão. Mediante estes argumentos, o presente trabalho tem a finalidade de desenvolver uma metodologia de apoio a decisão para a seleção de sistemas para geração de energia elétrica com biogás proveniente de resíduos sólidos urbanos, avaliando devidamente cada processo decisório de acordo com aspectos econômicos, operacionais, ambientais e sociais. Para o alcance deste objetivo fez se uso da lógica difusa baseada em regras e conjuntos fuzzy aplicados sobre diversos critérios, avaliando diferentes perspectivas. Os aperfeiçoamentos mais importantes apresentados na elaboração desta tese se referem à criação de uma etapa de relevância prévia aos critérios em análise, criação e seleção de meta-regras e forma de apresentação e construção de tais regras, facilitando o entendimento dos agentes de decisão para a avaliação do processo decisório e propiciando uma maior participação dos mesmos para obtenção de um resultado mais satisfatório. É possível observar ainda que os aperfeiçoamentos desenvolvidos permitiram a devida construção e averiguação das modelagens construídas. No estudo de caso principal aterro sanitário Caturrita II localizado na cidade de Santa Maria é verificada a aplicabilidade da metodologia de ajuda a decisão desenvolvida visando a seleção da fonte de geração de energia elétrica mais apropriada a ser utilizada no aterro em questão. Por fim, deve-se enfatizar que a partir dos aperfeiçoamentos alcançados durante o desenvolvimento desta tese, foi possível construir uma metodologia de ajuda a decisão genérica que pode ser aplicada não somente na seleção de sistemas de geração de energia em aterros, mas também na seleção de quaisquer sistemas de geração e armazenamento de energia, desde que todos os aspectos envolvidos no processo decisório sejam devidamente incorporados no problema em questão.

Durch den Ausbau an Wind- und PV-Anlagen in Deutschland wird der Flexibilitätsbedarf im Stromsystem steigen. Der Flexibilitätsbedarf kann zum einen durch verschiedene Technologien, z.B. Speicher oder Netze, und zum anderen durch die Stromnachfrage bereitgestellt werden. Eine gezielte Steuerung der Stromnachfrage wird als Demand Side Management (DSM) bezeichnet. Der zunehmend wetterabhängigen und fluktuierenden Stromerzeugung in Deutschland steht jedoch eine bis heute weitgehend unelastische Nachfrage gegenüber. In der Literatur sind verschiedene Arbeiten zu finden, die das Potential zur Lastabschaltung und verschiebung in Deutschland untersuchen. Hierbei liegt der Fokus auf absoluten Werten. Saisonale oder tageszeitliche Unterschiede bleiben dabei häufig unberücksichtigt. Die vorliegende Dissertation greift an dieser Stelle an und untersucht das Potential ausgewählter DSM-Anwendungen in stündlicher Auflösung. Die Ergebnisse zeigen, dass das verfügbare Potential starken saisonalen und tageszeitlichen Schwankungen unterliegt. Dementsprechend wird das DSM-Potential überschätzt, wenn nur absolute Werte betrachtet werden. Darüber hinaus zeigt die Autorin, welche Entwicklungen in den nächsten Jahren hinsichtlich der Verfügbarkeit des DSM-Potentials zu erwarten sind. Basierend auf der Potentialermittlung wird in der Dissertation die Rolle von DSM in einem EE-geprägten Stromsystem modellbasiert untersucht. Hierfür wird das lineare Optimierungsmodell ELTRAMOD, das den deutschen und europäischen Strommarkt abbildet, weiterentwickelt. Anhand verschiedener Szenarien wird zum einen der Beitrag von DSM zur Systemintegration von erneuerbaren Energien in Deutschland und zum anderen die Wechselwirkungen mit anderen Flexibilitätsoptionen (z.B. Speicher) untersucht. Die Ergebnisse zeigen, dass die DSM-Kategorien Lastabschaltung und verschiebung nur kurzzeitig auftretende Schwankungen der Einspeisung aus erneuerbaren Energien ausgleichen können. Zum Ausgleich großer Überschussmengen aus erneuerbaren Energien sind hingegen Power-to-X-Technologien, z.B. Power-to-Heat, besser geeignet.

Nos dias atuais as cidades são o epicentro de uma transformação energética, pois, são elas as principais consumidoras de matéria e energia. Energia fornecida, em sua maioria, através de um sistema convencional, centralizado e ineficiente. Dessa forma, são nos centros urbanos que poderão ser melhor implementadas estratégicas de eficiência energética e conservação de energia. Contudo, antes que os municípios se comprometam com novas iniciativas políticas e investimentos, o primeiro passo é melhorar a compreensão do sistema energético local. Por conseguinte, o objetivo central desta pesquisa é compreender de forma mais integrada o sistema energético de uma cidade através da aplicação de uma metodologia de análise. O município escolhido como estudo de caso é Porto Alegre, por ser uma cidade que se comprometeu em estabelecer mudanças para reduzir as emissões dos gases de efeito estufa, contudo, sem ainda possuir um plano de ação definido. A metodologia do trabalho é qualitativa e quantitativa e foi dividida em três etapas principais: a revisão bibliográfica, o desenvolvimento da metodologia de análise do sistema energético urbano e a aplicação da metodologia proposta. A revisão bibliográfica forneceu a base teórica para o desenvolvimento da metodologia de análise do sistema energético urbano. Esta metodologia prevê o levantamento de dados diversos que se complementam e, dessa forma, possibilitam uma análise integrada e mais aprofundada do sistema energético da cidade. Para tanto, a análise do sistema energético foi dividida em três etapas: caracterização municipal, análise da demanda de energia e levantamento da oferta das principais fontes energéticas locais. Para esta última etapa, visando um exercício concreto de avaliação, especificou-se o potencial de produção de eletricidade através do recurso solar. Os principais resultados da análise do sistema energético de Porto Alegre, entre os anos 2005 e 2014, destacam que o consumo de energia cresceu oito vezes mais que o aumento populacional e menos que a metade do PIB da cidade. Igualmente, no mesmo período, a frota de veículos, assim como o consumo de gasolina, aumentou 13 vezes mais que a população. Entre os setores econômicos analisados o setor transporte foi responsável, em 2014, pelo consumo de 60% da demanda final de energia da cidade. Nesse ano, a fonte de energia mais consumida foi a eletricidade, representando 28,1% do consumo final. Ainda analisando os dados de 2014, verificou-se que o consumo de eletricidade per capita de Porto Alegre pode ser considerado alto, 2,58 MWh/per capita, se igualando ao do Brasil e ao de alguns países desenvolvidos. Em relação ao potencial de produção de eletricidade, a partir da fonte solar, estimou-se um potencial de 2.549 GWh/ano, considerando todo o território da cidade, e de 772 GWh, considerando apenas o território que possuem edificações, aproximadamente 30% da cidade. Isto significa que se todos os consumidores residenciais e comerciais produzissem sua própria energia poderiam ser gerados 2.892 GWh por ano em Porto Alegre. Essa energia seria capaz de suprir 75,8% de toda a demanda de eletricidade da cidade em 2014. Ao final, ressaltou-se a importância de articular o planejamento energético ao planejamento urbano e ao plano de mobilidade urbana, uma vez que o sistema energético urbano está relacionado com os demais. / Nowadays cities at are the epicenter of an energetic transformation. Today, they are the main consumers of matter and energy. Most of that energy supplied through a conventional, centralized and inefficient system. Thus, it is in urban centers that strategic energy efficiency and energy conservation can be better implemented. However, before municipalities commit to new policy initiatives and investments, the first step is to improve understanding of the local energy system. Therefore, the central objective of this research is to understand in a more integrated way the energy system of a city through the application of a methodology of analysis of an urban energy system. The municipality chosen as a case study is Porto Alegre. It was chosen because is a city that has committed itself to establishing changes to reduce emissions of greenhouse gases, however, it does not have a defined plan of action. The methodology of the work is qualitative and quantitative and was divided into three main stages, among them: literature review, development of the methodology of urban energy system analysis, and application of the proposed methodology. The literature review provided the theoretical basis for the development of the methodology of analysis of the urban energy system. This methodology determines the collection of diverse data that complement each other and, thus, enable an integrated and more in-depth analysis of the city\'s energy system. In order to do so, the analysis of the energy system was divided into three stages: municipal characterization, analysis of the energy demand and survey of the supply of the main local energy sources. For this last stage, aiming a specific evaluation exercise, was specified the potential of electricity production through the solar resource.The main results of the analysis of the energy system of Porto Alegre, between 2005 and 2014, highlight that energy consumption grew eight times more than the population increase and less than half of the city\'s GDP. Also, in the same period, the car fleet grew 13 times more than the population. Among the economic sectors analyzed, the transportation sector was responsible for the consumption of 60% of the final energy demand of the city, in 2014. In that year, the most consumed energy source was electricity, representing 28.1% of final consumption. The per capita electricity consumption in Porto Alegre was considered high, 2.58 MWh/per capita, which equals that of Brazil and some developed countries. Regarding the potential for electricity production, it was determined a potential of 2,549 GWh/year (considering the entire territory of the city), and 772 GWh (considering only the territory that have buildings, approximately 30% of the city). This means that if all residential and commercial consumers produced their own energy could generate 2,892 GWh per year in Porto Alegre. This energy would be able to supply 75.8% of all city electricity demand. In the end, it was emphasized the importance of unifying the energy planning to the urban planning and to the urban mobility plan, since the urban energy system is related to both.

Orientador: Secundino Soares Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-08T14:25:59Z (GMT). No. of bitstreams: 1 Marques_ThyagoCarvalho_D.pdf: 9101920 bytes, checksum: 5cf6202ab737e2bcab996c2704ede5ec (MD5) Previous issue date: 2006 / Resumo: Este trabalho apresenta uma política para a operação energética do Sistema Nacional (SIN), baseada na representação individualizada das usinas hidrelétricas e termelétricas, na representação detalhada das características de operação dessas usinas, e na representação indireta da estocasticidade das vazões através demodelo de previsão. Essas características diferem a política operativa proposta daquela em vigor no setor elétrico brasileiro, que se baseia na modelagem equivalente de sistemas hidrotérmicos interligados. Diversos estudos de caso são apresentados com o intuito de avaliar o desempenho dessa polÂ'ıtica, desde o caso de sistemas hidrotérmicos simples com uma única usina até o caso completo do SIN sob condições reais. Para esse último caso, um procedimento de ajuste da operação foi implementado para assegurar o atendimento do mercado com as restrições de intercâmbio entre os subsistemas. Análises de sensibilidade foram realizadas em relação a restrições de intercâmbio, inflexibilidade das usinas termelétricas, a importância de algumas usinas hidrelétricas e mercado / Abstract: This work presents an operational policy for the mid term hydrothermal scheduling of the Brazilian Interconnected Power System (BIPS) based on the individual representation of the hydro and thermo power plants, the detailed representation of the plantsâ?¿ features and the indirect representation of the inflow stochasticity through a forecasting model. These characteristics differs the operational policy which is in use nowadays in BIPS, which is based on four interconnected subsystems represented by composite reservoirs. Several case studies are presented to evaluate the performance of the operational policy, from the simple case with a single hydro plant system to the complete case of the whole BIPS under real conditions. For this last case an operational adjustment procedure was implemented to assure the market attendance considering interchange constraints between the subsystems. Sensitivity analyses have been done with respected to interchange, minimum thermal generation, market, importance of hydro plants and system dimension / Doutorado / Energia Eletrica / Doutor em Engenharia Elétrica

Energy systems across the globe are going through a radical transformation as a result of technological and institutional changes, depletion of fossil fuel resources, and climate change. Accordingly, local energy initiatives are emerging and increasing number of the business models are focusing on the end-users. This requires the present centralized energy systems to be re-organized. In this context, Integrated community energy systems (ICESs) are emerging as a modern development to re-organize local energy systems allowing simultaneous integration of distributed energy resources (DERs) and engagement of local communities. With the emergence of ICESs new roles and responsibilities as well as interactions and dynamics are expected in the energy system. Although local energy initiatives such as ICESs are rapidly emerging due to community objectives, such as cost and emission reductions as well as resiliency, assessment and evaluation of the value that these systems can provide to both local communities and the whole energy system are still lacking. The value of ICESs is also impacted by the institutional settings internal and external to the system. With this background, this thesis aims to understand the ways in which ICESs can contribute to enhancing the energy transition. This thesis utilizes a conceptual framework consisting of institutional and societal levels in order to understand the interaction and dynamics of ICESs implementation.  Current energy trends and the associated technological, socio-economic, environmental and institutional issues are reviewed. The developed ICES model performs optimal planning and operation of ICESs and assesses their performance based on economic and environmental metrics. For the considered community size and local conditions, grid-connected ICESs are already beneficial to the alternative of solely being supplied from the grid, both in terms of total energy costs and CO2 emissions, whereas grid-defected systems, although performing very well in terms of CO2 emissions reduction, are still rather expensive. ICESs ensure self-provision of energy and can provide essential system services to the larger energy system. This thesis has demonstrated the added value of ICESs to the individual households, local communities and the society. A comprehensive institutional design considering techno-economic and institutional perspectives is necessary to ensure effective contribution of ICESs in the energy transition. / Energisystem över hela världen går igenom en radikal omvandling till följd av tekniska och institutionella förändringar, utarmning av fossila bränsleresurser och klimatförändringar. Följaktligen växer lokala energiinitiativ fram och ett ökande antal affärsmodeller fokuserar på slutanvändarna. Detta förutsätter att de nuvarande centraliserade energisystemen omorganiseras. I det här sammanhanget utvecklas integrerade samhällsenergisystem (ICES) som en modern utveckling för att omorganisera lokala energisystem som möjliggör samtidig integration av distribuerade energiresurser och engagemang från lokala samhällen. Med framväxten av ICES nya roller och ansvarsområden samt interaktioner och dynamik förväntas i energisystemet. Även om lokala energiinitiativ som ICES snabbt framträder på grund av samhällsmål, såsom kostnad och utsläppsminskningar samt resiliens, bedömning och utvärdering av det värde som dessa system kan ge till både lokala samhällen och hela energisystemet saknas fortfarande. Värdet av ICES-värden påverkas också av de institutionella inställningarna internt och externt för systemet. Med denna bakgrund syftar denna avhandling till att förstå hur ICES kan bidra till att förbättra energiövergången. Denna avhandling använder en konceptuell ram som består av institutionella och samhälleliga nivåer för att förstå samspelet och dynamiken i ICES-genomförandet. Nuvarande energitrender och de därtill hörande tekniska, socioekonomiska, miljömässiga och institutionella frågorna ses över. Den utvecklade ICES-modellen utför optimal planering och drift av ICES och bedömer deras prestanda baserat på ekonomiska och miljömässiga mätvärden. För den ansedda samhällsstorleken och lokala förhållandena är nätanslutna ICES redan fördelaktiga jämfört med alternativet att endast försörjas från nätet, både när det gäller totala energikostnader och koldioxidutsläpp, medan nät-defekterade system, även om de fungerar väldigt bra i termer av minskningen av koldioxidutsläppen fortfarande är ganska dyra. ICES garanterar självförsörjning av energi och kan tillhandahålla viktiga systemtjänster till det större energisystemet. Denna avhandling har visat mervärdet av ICES till de enskilda hushållen, lokalsamhällena och samhället. En omfattande institutionell utformning med hänsyn till de tekno-ekonomiska och institutionella perspektiven är nödvändigt för att säkerställa ett effektivt bidrag från ICES i energiövergången. / Los sistemas energéticos en todo el mundo atraviesan una transformación radical como resultado de cambios tecnológicos e institucionales, el agotamiento de combustibles fósiles y el cambio climático. Por consiguiente, las iniciativas locales de energía están surgiendo y los modelos de negocio se centran cada vez más en los usuarios finales. Esto requiere la reorganización de los actuales sistemas energéticos centralizados. En este contexto, los sistemas integrados de energía comunitaria (ICES, por sus siglas en inglés) están emergiendo como un desarrollo moderno para reorganizar los sistemas energéticos locales, permitiendo la integración simultánea de los recursos energéticos distribuidos y la participación de las comunidades locales. Con la aparición de ICESs se esperan nuevos roles y responsabilidades, así como interacciones y dinámicas, en el sistema energético. Aunque las iniciativas locales en materia de energía, como las ICESs, están surgiendo rápidamente debido a los objetivos de la comunidad, tales como la reducción de costos y emisiones, así como la resiliencia, y la evaluación, siguen careciendo del valor que estos sistemas pueden brindar tanto a las comunidades locales como a todo el sistema energético. El valor de los ICESs también se ve afectado por los entornos institucionales tanto internos como externos al sistema. Con este trasfondo, esta tesis pretende comprender las formas en que los ICESs pueden contribuir a mejorar la transición energética. Esta tesis utiliza un marco conceptual que consiste en niveles institucionales y sociales para comprender la interacción y dinámica de la implementación de los ICESs.  Además, esta tesis revisa las tendencias actuales de energía y los problemas tecnológicos, socioeconómicos, ambientales e institucionales asociados. La tesis desarrolla un modelo que optimiza la planificación y el funcionamiento óptimos de ICESs y evalúa su funcionamiento basado en métricas económicas y ambientales. Para el tamaño de la comunidad y las condiciones locales consideradas, los ICESs conectados a la red ya son beneficiosos tanto en términos de costos totales de energía como de emisiones de CO2 comparado con la alternativa de ser suministrados únicamente desde la red, mientras que los sistemas aislados y desconectados de la red, aunque desempeñándose muy bien en términos de reducción emisiones de CO2, siguen siendo bastante más costosos. Los ICESs garantizan el autoabastecimiento de energía y pueden proporcionar servicios esenciales al resto del sistema energético. Esta tesis demuestra el valor añadido de los ICESs a los hogares individuales, las comunidades locales y la sociedad. Un diseño integral que considere las perspectivas tecno-económicas e institucionales es necesario para asegurar la contribución efectiva de los ICESs en la transición energética. / Energiesystemen over de hele wereld gaan door een radicale transformatie als gevolg van technologische en institutionele veranderingen, uitputting van fossiele brandstoffen en klimaatverandering. Bijgevolg komen lokale energie-initiatieven op en richten steeds meer verdienmodellen zich op de eindgebruikers. Dit vereist dat de huidige gecentraliseerde energiesystemen opnieuw worden georganiseerd. In deze context komen geïntegreerde energiegemeenschapssystemen (ICESs) op als een moderne ontwikkeling om lokale energiesystemen te reorganiseren, welke gelijktijdige integratie van lokale energiebronnen en betrokkenheid van lokale gemeenschappen mogelijk maakt. Het wordt verwacht dat de opkomst van ICESs zowel nieuwe rollen en verantwoordelijkheden met zich meebrengt. Hoewel lokale energie-initiatieven zoals ICESs snel opkomen door de  doelstellingen van de gemeenschap, zoals kosten- en emissiereducties en veerkracht, schort het nog steeds aan beoordeling en evaluatie van de waarde die deze systemen kunnen hebben voor zowel de lokale gemeenschappen als het hele energiesysteem. De waarde van ICESs wordt ook beïnvloed door de institutionele kenmerken binnen en buiten het systeem. Met deze achtergrond beoogt dit proefschrift te begrijpen op welke manieren de ICESs kunnen bijdragen aan de verbetering van de energietransitie. Dit proefschrift maakt gebruik van een conceptueel raamwerk bestaande uit institutionele en maatschappelijke niveaus om de interactie en dynamiek van de implementatie van de ICES te begrijpen. De huidige energietrends en de bijbehorende technologische, sociaal-economische, milieu- en institutionele problemen worden beoordeeld. Het ontwikkelde ICES-model voert optimale planning en gebruik van ICESs uit en beoordeelt hun prestaties op basis van economische en milieu-indicatoren. Voor de beschouwde gemeenschapsgrootte en lokale omstandigheden zijn  op het net aangesloten ICESs al voordelig ten opzichte van het alternatief waarbij uitsluitend vanuit het net wordt geleverd, zowel wat betreft de totale energiekosten als de CO2-uitstoot, terwijl de grid-defected systemen, hoewel heel goed presterend in termen van CO2-emissiereductie, nog steeds vrij duur zijn. ICESs zorgen voor zelfvoorziening van energie en kunnen essentiële systeemdiensten leveren aan het grotere energiesysteem. Dit proefschrift heeft de toegevoegde waarde van ICESs voor de individuele huishoudens, lokale gemeenschappen en de samenleving aangetoond. Een uitgebreid institutioneel ontwerp met inachtneming van techno-economische en institutionele perspectieven is nodig om de effectieve bijdrage van de ICESs in de energietransitie te waarborgen. / <p>QC 20170911</p> / Sustainable Energy Technologies and Strategies

Models and simulators have been widely used in urban contexts for many decades. The drawback of most current models is that they are normally designed for specific objectives, so the elements considered are limited and they do not take into account the potential synergies between related systems. The necessity of a framework to model complex smart city systems with a comprehensive smart city model has been remarked by many authors. Therefore, this PhD thesis presents: i) a general conceptual framework for the modelling of energy related activities in smart cities, based on determining the spheres of influence and intervention areas within the city, and on identifying agents and potential synergies among systems, and ii) the development of a holistic energy model of a smart city for the assessment of different courses of action, given its geo-location, regulatory and technical constraints, and current energy markets. This involves the creation of an optimization model that permits the optimal planning and operation of energy resources within the city. In addition, several analyses were carried out to explore different hypothesis for the smart city energy model, including: a)      an assessment of the importance of including network thermal constraints in the planning and operation of DER systems at a low voltage distribution level, b)      an analysis of aggregator’s market modelling approaches and the impact on prices due to DER aggregation levels, and c)      an analysis of synergies between different systems in a smart city context. Some of the main findings are: It is sensible to not consider network thermal constraints in the planning of DER systems. Results showed that the benefit decrement of considering network constraints was approximatively equivalent to the cost of reinforcing the network when necessary after planning without considering network constraints. The level of aggregation affects the planning and overall benefits of DER systems. Also, price-maker approaches could be more appropriate for the planning and operation of energy resources for medium to large aggregation sizes, but could be unnecessary for small sizes, with low expected impact on the market price. Synergies between different energy systems exist in an interconnected smart city context. Results showed that the overall benefits of a joint management of systems were greater than those of the independently managed systems. Lastly, the smart city energy model was applied to a case study simulating a real smart city implementation, considering five real districts in the southern area of Madrid, Spain. This analysis allowed to assess the potential benefits of the implementation of a real smart city programme, and showed how the proposed smart city energy model could be used for the planning of pilot projects. To the best of our knowledge, such a smart city energy model and modelling framework had not been developed and applied yet, and no economic results in terms of the potential benefits of such a smart city initiative had been previously reported. / <p>QC 20171010</p>