The declining cost of photovoltaic (PV) modules has enabled the vision of ubiquitous photovoltaic (PV) power to become feasible. Emerging PV technologies are facilitating the creation of intentionally non-flat PV modules, which create new applications for this sustainable energy generation currently not possible with the traditional rigid, flat silicon-glass modules. However, since the photovoltaic cells are no longer coplanar, there are significant new requirements for the power electronics necessary to convert the native form of electricity into a usable form and ensure maximum energy harvest. Non-uniform insolation from cell-to-cell gives rise to non-uniform current density in the PV material, which limits the ability to create series-connected cells without bypass diode or other ways to shunt current, which is well known in the maximum power tracking literature. This thesis presents a modeling approach to determine and quantify the variations in generation of energy due to intentionally non-flat PV geometries. This will enable the power electronics circuitry to be optimized to harvest maximum energy from PV pixel elements – clusters of PV cells with similar operating characteristics. This thesis systematically compares different geometries with identical two-dimensional projection "footprints" for energy harvest throughout the day. The results show that for the same footprint, a semi-cylindrical surface harvests more energy over a typical day than a flat plate. The modeling approach is then extended to demonstrate that by using non flat geometries for PV panel, the availability of a remotely located stand-alone power system can be increased when compared to a flat panel of same footprint. These results have broad application to a variety of energy scavenging scenarios in which either total energy harvested needs to be maximized or unusual geometries for the PV active surfaces are required, including building-integrated PV. This thesis develops the analysis of the potential energy harvest gain for advanced non-planar PV collectors as a necessary first step towards the design of the power electronics circuits and control algorithms to take advantage of the new opportunities of conformal and non-flat PV collectors.

AstraZeneca is one of the largest biopharmaceutical companies in the world, and one of the facilities they have is located in Gärtuna, Södertälje. The facility itself is very big with a floor area of 560.000m2 and has a complex energy system. Caverion holds a facility management contract at AstraZenca, hence operates some of the energy system. The energy investigation of this thesis is part of the work of Caverion to ensure a sustainable energy system in Gärtuna. The energy investigation will include mapping of the energy distribution, seeking for potential of improvements and carry out suggestions for energy optimizations. The methods used during the investigation was a literature study, interviews with personnel of both Caverion and AstraZenca, study of the energy system and calculations relevant to the field of study. The mapping of the energy system includes the heat, steam and cooling distribution. When the mapping of the system was done it was clear that the areas with most potential for improvements were the steam and cooling distribution.The mapping of the steam distribution shows a loss of nearly 46% of the steam at year 2014 and the corresponding cost of about 13,640,000 SEK. Even though the steam distribution showed great potential for improvements, it was found that the work of investigating the system would be too difficult for the scope of the thesis. The cooling distribution however is more accessible and the potential is still high due to low coefficient of performance. Two suggestions for energy optimizations were carried out. The first suggestions involves upgraded electric fan motors for some of the cooling towers, and the second suggestion is to modify existing dry coolers in benefit to utilize free cooling during winter period. The fan motor upgrade based on calculations is estimated to result in a yearly energy saving of at least 1526 MWh and a corresponding cost saving of at least 800,000 SEK per year after the pay-off time (9 months). The dry cooler modification based on calculations is estimated to result in a yearly energy saving of 3053 MWh and a yearly cost saving of 2,083,449 SEK after the pay-off period of 5 months. The investigation carried out in this thesis is relevant to both Caverion and AstraZeneca as it points out the areas with potential of improvements and also gives suggestions on energy optimizations that will reduce energy consumption and result in energy cost savings.

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