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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.
151

Techno-economic feasibility for residential Local Energy Communities: Case study of Italy

Colarullo, Linda January 2021 (has links)
The use of renewable energy has proven to be essential for the decarbonisation of the energy system, bringing changes on both the production and consumption side, with an increase of renewable energy in the mix and a change in the role of consumers. From passive actors, Consumers are becoming Prosumers (producers and consumers) of self-generated energy, with the potential of becoming the pillar of the energy sector transition. The European Union set ambitious goals for the realization of a low carbon society by 2050, giving birth to several energy related initiatives. From a regulatory perspective, Europe is indeed paving the way for an internal energy market revolution, that sees the introduction of new actors among which, Local Energy Communities (LEC). In the progressive transition from a centralized to a decentralized system with intelligent and interconnected production sources, consumers are allowed to produce, store, share or resell their energy directly or as energy cooperatives, and can manage demand either independently or through aggregators. In this context Energy Communities take shape. In accordance with the definition given in the European RED directive "Renewable Energy Directive", this study refers to energy communities as a set of energy users who, through cooperatives, non-profit associations, or other legal forms, make common decisions for the satisfaction of their energy needs, with the aim of providing environmental, social and economic benefits. The overall objective of the study is to gain a better understanding of the environmental, grid and social impacts of local energy communities, as well as of the factors that can potentially enable or inhibit the deployment of such communities. The emergence of prosumers and energy communities raise new challenges in terms of technologies and technical requirements for the interaction with the electricity grid, in terms of the need for new business models and new energy policies and regulatory framework, to encourage these new configurations and unlock their benefits as effectively as possible. In the context of this work, a model for the assessment of LECs viability has been built; it examines the consumption and renewable generation loads, with the possibility to measure the effects of adding a battery storage system in the community configuration. The profitability of residential customers participating in a LEC is investigated for four different technological community scenario: (i) solely stand-alone PV plant (ii) stand-alone PV plant with the addition of a solar battery for self-consumption maximization (iii) stand-alone PV plant with the addition of a battery storage system for Demand Side Management behind-the-meter and (iv) stand-alone PV plant with the addition of a battery storage system for Demand Side Management front-of-the-meter. The economic impact of storage on LEC energy usage has been studied while considering the technical aspects of the proposed system. The simulation analysis – based on real residential demand profiles, renewable generation curves, battery energy storage functioning, market pricing and incentives scheme, showed that energy sharing and collective investment in residential scale renewable assets and batteries can be economically feasible, but the economics can significantly fluctuate with changes in parameters such as technology cost, LECs incentives, electricity prices, and that therefore the convenience of one scenario over the others should be verified each time the conditions change. Also, the type of services for which the battery can get revenues may disrupt the conclusions reached. The aim of the work, however, was to build a model easily adaptable to the variation of these parameters, in order to calculate case by case economics and convenience of any possible community configuration. / Användningen av förnybar energi har visat sig vara avgörande för att minska koldioxidutsläppen från energisystemet, vilket medför förändringar både på produktions- och konsumtionssidan, med en ökad andel förnybar energi i mixen och en förändrad roll för konsumenterna. Från att ha varit passiva aktörer blir konsumenterna nu Prosumers, producenter och konsumenter av egenproducerad energi, med potential att bli en pelare i övergången inom energisektorn. Europeiska unionen har satt upp ambitiösa mål om att förverkliga ett samhälle med låga koldioxidutsläpp senast 2050, vilket har gett upphov till flera energirelaterade initiativ. Ur ett regleringsperspektiv banar Europa verkligen väg för en revolution på den inre energimarknaden, där nya aktörer kommer att introduceras, bland annat lokala energikommuner. I den gradvisa övergången från ett centraliserat till ett decentraliserat system med intelligenta och sammankopplade produktionskällor får konsumenterna producera, lagra, dela eller sälja sin energi direkt eller som energikooperativ, och de kan hantera efterfrågan antingen självständigt eller genom aggregatorer. I detta sammanhang tar energisamhällen form. I enlighet med definitionen i det europeiska direktivet om förnybar energi i den här studien avses med energisamhällen en grupp energianvändare som genom kooperativ, ideella föreningar eller andra juridiska former fattar gemensamma beslut för att tillgodose sina energibehov, i syfte att skapa miljömässiga, sociala och ekonomiska fördelar. Det övergripande målet med studien är att få en bättre förståelse för de miljömässiga, nätmässiga och sociala konsekvenserna av lokala energisamhällen, samt för de faktorer som kan möjliggöra eller hindra införandet av sådana samhällen. Framväxten av prosumenter och energisamhällen ger upphov till nya utmaningar när det gäller teknik och tekniska krav för samverkan med elnätet, när det gäller behovet av nya affärsmodeller och ny energipolitik och regelverk för att uppmuntra dessa nya konfigurationer och frigöra deras fördelar på ett så effektivt sätt som möjligt. Inom ramen för detta arbete har en modell för bedömning av LECs lönsamhet byggts upp. Den undersöker förbrukning och belastning från förnybar produktion, med möjlighet att mäta effekterna av att lägga till ett batterilagringssystem i samhällskonfigurationen. Lönsamheten för privatkunders deltagande i ett LEC undersöks för fyra olika tekniska samhällsscenarier: (i) enbart fristående solcellsanläggning, (ii) fristående solcellsanläggning med tillägg av ett solcellsbatteri för maximering av självförbrukningen, (iii) fristående solcellsanläggning med tillägg av ett batterilagringssystem för styrning av efterfrågan bakom mätaren och (iv) fristående solcellsanläggning med tillägg av ett batterilagringssystem för styrning av efterfrågan framför mätaren. Lagringens ekonomiska inverkan på LECs energianvändning har studerats samtidigt som de tekniska aspekterna av det föreslagna systemet har beaktats. Simuleringsanalysen - som i skrivande stund bygger på verkliga efterfrågeprofiler för bostäder, kurvor för förnybar produktion, batterilagringens funktion, marknadens prissättning och incitamentssystem - visade att energidelning och kollektiva investeringar i förnybara tillgångar och batterier i bostadsområden kan vara ekonomiskt genomförbara, men att ekonomin kan fluktuera avsevärt med förändringar i parametrar som teknikkostnader, incitament för LEC:s och elpriser, och att det därför är lämpligt att kontrollera om det är fördelaktigt att välja ett scenario framför de andra varje gång förhållandena förändras. Även den typ av tjänster som batteriet kan få intäkter för kan påverka de slutsatser som dras. Syftet med arbetet var dock att bygga en modell som lätt kan anpassas till variationen av dessa parametrar, för att från fall till fall beräkna ekonomin och bekvämligheten hos alla möjliga konfigurationer av samhället.
152

Grid Tariff Design for Efficient Utilisation of the Distributor Grid : A qualitative study with actors on the Swedish electricity market

Haikola, Matilda, Söderberg, Malin January 2020 (has links)
The Swedish electricity system is transitioning due to the establishment of climate policy goals and trends related to technology and demographics. The transition has resulted in an increased demand for electricity. The increased demand for electricity in combination with lack of forecasts, planning and coordination between actors in the electricity sector has led to the occurrence of grid congestion. Extending the network is time-consuming and requires substantial investments. Instead, an alternative is to utilise the available grid capacity more efficiently by implementing flexibility solutions. Flexibility can be achieved by implementing incentives such as grid tariffs. This solution has recently gained much attention in Sweden, but it is not apparent how grid tariffs should be designed. The purpose of this thesis is to investigate how distribution grid tariffs could be designed to incentivise different actors to contribute to flexibility in a way that results in an efficient use of the electrical grid. A qualitative study was performed, collecting empirical data through semistructured interviews with actors in the Swedish electricity market. The aim is that the results from this thesis will act as a basis for DSOs planning to design grid tariffs with the purpose to utilise the grid more efficiently. The findings present a ToU capacity charge with off-peak periods that are free of charge as the preferable main price signal in the tariff to achieve efficient utilisation of the grid. It is further argued that other structural elements can complement the ToU capacity charge. A small fixed charge could be added in order to contribute to the cost reflectiveness of the grid tariff. A small energy charge could be incorporated in order to provide consumer with incentives to be flexible below the current metered maximum power and strengthen the signal from the ToU capacity charge. A small energy charge can avert difficulties related to providing incentives below the current metered maximum, as it still can provide some incentives to be flexible, or strengthen the signal from the ToU capacity charge. Further, the energy charge can ensure sustainability if customers respond well to a ToU capacity charge and to compensate solar PV customers. Furthermore, recommendations to further enable the grid tariffs potential to provide price signals include shifting the focus of the revenue cap from CapEx to OpEx and exploring the hampering signals of the energy tax as well as contradicting price signals from the wholesale electricity price. / Det svenska elsystemet genomgår en förändring till följd av införandet av klimatmål och trender relaterade till teknik och demografi. Denna förändring har resulterat i ett ökat effektbehov. Ett ökat effektbehov i kombination med bristande prognostisering, planering och samordning mellan aktörer inom elsektorn har lett till uppkomsten av kapacitetsbrist. Att bygga ut elnätet är tar tid och kräver större investeringar. Ett alternativ är att istället utnyttja det befintliga elnätet mer effektivt genom att implementera flexibilitetslösningar. Flexibilitet kan uppnås genom att införa incitament i form av elnätstariffer. Denna lösning har nyligen fått mycket uppmärksamhet i Sverige, men det är inte klart inte hur dessa elnätstariffer ska utformas. Syftet med detta arbete är att undersöka hur distributionsnätets tariffer kan utformas för att stimulera olika aktörer att bidra med flexibilitet på ett sätt som resulterar i en effektiv användning av det befintliga elnätet. En kvalitativ studie genomfördes där empiriska data samlades in genom semistrukturerade intervjuer med aktörer på den svenska elmarknaden. Syftet är att resultaten från detta arbete ska fungera som ett underlag för nätägare som planerar att utforma elnätstariffer med syftet att utnyttja nätet mer effektivt. Resultaten visar att en ToU-effektavgift med gratis off-peak perioder bör vara den huvudsakliga prissignalen i en elnätstariff som ämnar att utnyttja det befintliga nätet mer effektivt. Det visar även att andra strukturella element kan komplettera ToU-effektavgiften. En mindre fast avgift kan adderas i syfte att göra elnätstariffen mer kostnadsriktig. En mindre energiavgift kan införas för att ge kunder incitament att vara flexibla även under den nuvarande uppmätta maximala effekten och stärka signalen från ToU-effektavgiften. Vidare kan energiavgiften säkerställa tillräckliga intäkter för nätägaren om kunderna svarar bra på en ToU-effektavgift och för att kompensera kunder med solceller. Ytterligare rekommendationer för att möjliggöra prissignaler genom elnätstariffer inkluderar att skifta fokus på intäktsramen från CapEx till OpEx och utforska de hämmande prissignalerna från energiskatten och de motstridiga prissignalerna från elhandelspriset.
153

Business Model Design for Digital Energy Trading Platforms : An Exploratory Study of Local Energy Market Designs / Affärsmodeller för digitala energidelningsplatformar : En utforskande studie av lokala energimarknader

Granath, Isabelle, Holmlund, Kristin January 2020 (has links)
The traditional electricity market, holding centralized authority over consumers, is no longer adequate seeing a shift towards a more electrified, decentralized, and digitalized society. Increased energy prices, raising concerns about climate change, and tightening governmental regulations have resulted in that an extensive diffusion of renewable energy sources has evolved. This development is expected to change the structure of the sector, despite that an appropriate market design that can deal with these remains to be identified. The purpose of this study was to investigate how a business model of a digital platform, managing energy trading within a local community could be designed. This study contributes to a new dimension of energy transitions within a Multi-Level Perspective by studying a particular field of the transition in terms of flexibility market platforms. The rising need for flexible solutions, making the consumer a prosumer, and enabling shared energy through a digital platform involves uncertainty and challenges, where a suitable business model linking new technology to the emerging market needs to be defined. Despite the novelty of the research field of local energy markets, the aim of investigating business model designs for a local energy market platform has been reached through an exploratory case study and integration of theories from several fields. This study makes an analytical contribution of investigating five pioneering projects, all developing digital platforms enabling integration of flexibility into the electricity market. This further contributes to the design-implementation gap of theories when developing a local energy market, by suggesting the most vital parameters to take into account. Based on the findings, a suggestion on a suitable business model design and a corresponding market design was developed. The main objective of the proposed market design is to serve as a basis to bring forward flexibility available from prosumers and their controllable demand and supply arrangement, including renewable energy technology generation and storage devices. The intention is to maintain a balanced and transparent distribution network at the lowest possible costs, while, at the same time functioning as reserve storage towards the main grid, reducing the risk of capacity shortage. Additional insights were raised that can be helpful in the evaluation of utilizing flexibility energy assets before making grid investments, following the recently presented recommendation of the EU's Clean Energy package. / Den traditionella elmarknaden, karaktäriserad av en centraliserad styrning, är inte längre hållbar då utvecklingen av marknaden går mot ett allt mer elektrifierat, decentraliserat och digitaliserat samhälle. Ökande energipriser, växande oro för klimatfrågor tillsammans med en allt snävare reglering av energimarknaden har resulterat i en omfattande ökning av förnybara energikällor. Denna utveckling förväntas förändra sektorns struktur, där en lämplig marknadsdesign som kan hantera detta återstår att identifiera. Syftet med denna studie var att undersöka hur en affärsmodell för en digital plattform, anpassad för att hantera lokal energidelning, kan utformas. Denna studie bidrar till en ny dimension av energitransformationen från ett multi-nivå-perspektiv genom att studera ett särskilt område av övergången i form av flexibla marknadsplattformar. Det ökande behovet av flexibla lösningar, där konsumenter blir prosumenter och energi delas lokalt via digitala plattform innebär osäkerheter och utmaningar. En lämplig affärsmodell som kan anknyta de nya tekniska lösningarna som krävs till lokala energimarknader bör därav definieras. Trots att forskningsområdet som berör lokala energimarknader kan anses relativt nytt och delvis outforskat, har målet att undersöka affärsmodellkoncept för en lokal energimarknadsplattform uppnåtts genom en fallstudie och iterationer av teorier inom flertalet områden. Denna studie bidrar med en analytisk undersökning av fem innovativa projekt som alla utvecklar digitala plattformar för att möjliggöra integrering av flexibilitet till elmarknaden. Detta bidrar även till det kunskapsgap som har identifierats mellan design och implementering fas vid utvecklandet av lokala energimarknader, genom föreslagna parameter som anses grundläggande och som bör tas hänsyn till. Baserat på resultatet presenterades ett förslag på en lämplig design för affärsmodell samt en tillhörande marknadsdesign. Huvudsyftet med den föreslagna marknadsdesignen är att utgöra en grund för gynnandet av en mer flexibel elektricitet hantering. Detta möjliggörs genom introduktionen av prosumenter till marknaden, där allt mer elektricitet produceras från förnybara källor och där konsumtion samt produktion regleras med hjälp av integrerade lagringsenheter. Målet är att upprätthålla ett balanserat och transparent distributionsnät till lägsta möjliga kostnad, medan marknaden även fungerar som ett reservlager mot kraftnätet, vilket minskar risken för kapacitetsbrist runt om i Sverige. Ytterligare insikter från denna studie påvisar hur de befintliga energitillgångarna kan utnyttjas på ett mer flexibelt och effektivt sätt, vilka stöds av de nyligen presenterade rekommendationerna från EU:s Clean Energy-paket.
154

A Mycorrhizal Model for Transactive Energy Markets

Gould, Zachary M. 08 September 2022 (has links)
Mycorrhizal Networks (MNs) facilitate the exchange of resources including energy, water, nutrients, and information between trees and plants in forest ecosystems. This work explored MNs as an inspiration for new market models in transactive energy networks, which similarly involve exchanges of energy and information between buildings in local communities. Specific insights from the literature on the structure and function of MNs were translated into an energy model with the aim of addressing challenges associated with the proliferation of distributed energy resources (DERs) at the grid edge and the incorporation of DER aggregations into wholesale energy markets. First, a systematic review of bio-inspired computing interventions applied to microgrids and their interactions with modern energy markets established a technical knowledge base within the context of distributed electrical systems. Second, a bio-inspired design process built on this knowledge base to yield a structural and functional blueprint for a computational mycorrhizal energy market simulation. Lastly, that computational model was implemented and simulated on a blockchain-compatible, multi-agent software platform to determine the effect that mycorrhizal strategies have on transactive energy market performance. The structural translation of a mapped ectomycorrhizal network of Douglas-firs in Oregon, USA called the 'wood-wide web' created an effective framework for the organization of a novel mycorrhizal energy market model that enabled participating buildings to redistribute percentages of their energy assets on different competing exchanges throughout a series of week-long simulations. No significant changes in functional performance –- as determined by economic, technical, and ecological metrics – were observed when the mycorrhizal results were compared to those of a baseline transactive energy community without periodic energy asset redistribution. Still, the model itself is determined to be a useful tool for further exploration of innovative, automated strategies for DER integration into modern energy market structures and electrical infrastructure in the age of Web3, especially as new science emerges to better explain trigger and feedback mechanisms for carbon exchange through MNs and how mycorrhizae adapt to changes in the environment. This dissertation concludes with a brief discussion of policy implications and an analysis applying the ecological principles of robustness, biodiversity, and altruism to the collective energy future of the human species. / Doctor of Philosophy / Beneath the forest floor, a network of fungi connects trees and plants and allows them to exchange energy and other resources. This dissertation compares this mycorrhizal network (mycorrhiza = fungus + root) to a group of solar-powered buildings generating energy and exchanging it in a local community marketplace (transactive energy markets). In the analogy, the buildings become the plants, the solar panels become the leaves, and the electrical grid represents the mycorrhizal network. Trees and plants produce their own energy through photosynthesis and then send large portions of it down to the roots, where they can trade it or send it to neighbors via the mycorrhizal network. Similarly, transactive energy markets are designed to allow buildings to sell the energy they produce on-site to neighbors, usually at better rates. This helps address a major infrastructure challenge that is arising with more people adding roof-top solar to their homes. The grid that powers our buildings is old now and it was designed to send power from a central power plant out to its edges where most homes and businesses are located. When too many homes produce solar power at the same time, there is nowhere for it to go, and it can easily overload the grid leading to fires, equipment failures, and power outages. Mycorrhizal networks solve this problem in part through local energy balancing driven by cooperative feedback patterns that have evolved over millennia to sustain forest ecosystems. This work applies scientific findings on the structure and function of mycorrhizal networks (MNs) to energy simulation methods in order to better understand the potential for building bio-inspired energy infrastructure in local communities. Specifically, the mapped structure of a MN of douglas-fir trees in Oregon, USA was adapted into a digital transactive energy market (TEM) model. This adaptation process revealed that a single building can connect to many TEMs simultaneously and that the number of connections can change over time just as symbiotic connections between organisms grow, decay, and adapt to a changing environment. The behavior of MNs in terms of when those connections are added and subtracted informed the functionality of the TEM model, which adds connections when community energy levels are high and subtracts connections when energy levels are low. The resulting 'mycorrhizal' model of the TEM was able to change how much energy each connected household traded on it by changing the number of connections (more connections mean more energy and vice versa). Though the functional performance of the mycorrhizal TEM did not change significantly from that of a typical TEM when they were the context of decentralized computer networks (blockchains) and distributed artificial intelligence. A concluding discussion addresses ways in which elements of this new model could transform energy distribution in communities and improve the resilience of local energy systems in the face of a changing climate.
155

Relaxing dc capacitor voltage of power electronic converters to enhance their stability margins

Zakerian, Ali 12 May 2023 (has links) (PDF)
Recently, due to the increasing adoption of distributed energy resource (DER) technologies including battery energy storage (BES) and electric vehicle (EV) systems, bidirectional power converters are becoming more popular. These converters are broadly utilized as interface devices and provide a bidirectional power flow in applications where the primary power supply can both supply and receive energy. A dc capacitor, called the dc-link, is an important component of such bidirectional converters. For a wide range of applications, the converter is required to control the dc-link voltage. Commonly, a proportional-integrating (PI) controller is used by the dc capacitor voltage controller to generate a set-point for the inner current controller. This approach tightly regulates the dc-link voltage to a given value. The research presented in this dissertation shows that such an approach compromises the stability margins of the converter for reverse power flow and weak grid conditions. It is shown that by allowing a small variation of dc capacitor voltage in proportion to the amount of power flowing through the converter, the stability and robustness margins are improved. This approach also simplifies the design process and can be applied to both dc/dc and dc/ac (single-phase and three-phase) converters. Moreover, it grants an inherent power sharing capability when multiple converters share the same dc-link terminals; removing the need to a communication link between parallel converters. The proposed controller is equipped with a current limiting mechanism to protect the converter during low-voltage/over-current transients. Detailed analyses, simulations, comparisons, and experimental results are included to illustrate the effectiveness of the proposed control approach. To mathematically establish the properties of the proposed method in a single-phase dc/ac application, this dissertation also derives a new and systematic modeling approach for a grid-connected bidirectional single-phase inverter controlled in stationary frame. Implementing the control system in the stationary frame has advantages over rotating frame. However, the combination of dc and ac state variables and nonlinearities make its stability analysis challenging. In the proposed model, an imaginary subsystem is properly generated and augmented to allow a full transformation to a synchronous rotating frame. The proposed modeling strategy is modular and has a closed form which facilitates further extensions. It is successfully used to demonstrate enhanced stability margins of the proposed controller.
156

Avaliação da atratividade de negócios em geração distribuída e economia de energia elétrica: piloto aplicado dentro dos estudos de PIR na RAA. / Business attractiveness assessment on distributed generation and measures of energy saving: pilot applied on IRP studies within administrative region of Araçatuba.

Silva Junior, Barnabé da 07 May 2012 (has links)
O objetivo da dissertação foi o desenvolvimento de um modelo de avaliação rápida da atratividade de oportunidades de negócios em recursos energéticos renováveis dentro de uma região geográfica delimitada, valendo-se dos resultados do Planejamento Integrado de Recursos Energéticos (PIR) para a região analisada, complementado com outras bases bibliográficas primárias e secundárias. O uso dos resultados do PIR propiciou o acesso rápido a avaliações prontas dos recursos energéticos em três dimensões1, além da dimensão técnico-econômica, incluindo opiniões e posições da sociedade local e nacional (técnicos e não técnicos). No estudo piloto, o modelo é aplicado em cinco recursos energéticos renováveis dentro da Região Administrativa de Araçatuba (RAA), noroeste do estado de São Paulo. Os recursos avaliados são: (a) de oferta: Geração eólica (EOL); Cogeração por Biomassa de Cana-de-açúcar (BIO); e Pequenas Centrais Hidroelétricas (PCH); (b) de demanda (medidas de economia): Troca de Lâmpadas Incandescentes por Fluorescentes Compactas e Troca de Chuveiros Elétricos por Aquecedores Solares. Os principais resultados do modelo de avaliação foram (i) um modelo de fluxo de caixa funcional para a avaliação dos recursos de geração; (ii) para cada recurso de geração: cálculo das principais Figuras de Mérito Econômico Financeiro (VPL, TIR, PayBack Descontado, preço de equilíbrio2 da energia gerada e demanda relevante de capital de giro); (iii) para as medidas de economia de energia: cálculo das figuras de mérito econômico-financeiras (Custo do Ciclo de vida anualizado (CCVA) e PayBack Descontado); (iv) pontos notáveis da análise de sensibilidade das figuras de mérito, obtidas pela variação das principais parâmetros de entrada dos modelos matemáticos representativos dos recursos; (v) análise geral dos riscos em empreender os recursos avaliados; e (vi) diagnóstico da atratividade de investimento em cada recurso: não atrativo, atrativo com atenção, e atrativo. No contexto do estudo piloto, o recurso lâmpada fluorescente recebeu diagnóstico de atrativo; os recursos Cogeração por biomassa e coletor solar receberam o diagnóstico de atrativo com atenção, e os recursos Geração eólica e PCH receberam o diagnóstico de não atrativos para investimento, todos dentro da região do estudo de caso. / The purpose of this work was the expedite assessment of business opportunities attractiveness in renewable energy resources within a limited geographical area, based on the results of the Integrated Resources Planning for Energy (IRP), developed for the same area, and supplemented with other primary and secondary information sources. The use of IRP\'s information made possible, quickly and easy, the assessments of energy resources in extra three dimensions3, beyond the usual technical- economic one, including views and positions of local and national stakeholders (technical and nontechnical). In the pilot study, the model is applied in five renewable energy resources within the Administrative Region of Araçatuba (RAA), northwest of São Paulo state, Brazil. The evaluated energy resources were: (a) supply side: wind generation (EOL); Cogeneration by Biomass of Sugar Cane (BIO); and Small Hydro Power plants (SHP); (b) demand side (measures of energy economy): replacement of Compact Fluorescent Incandescent bulbs by Fluorescent ones and replacement of Electric Showers by Solar Heater ones. The main results of the proposed evaluation model were (i) a functional cash flow model , useful to assess the generation resources; (ii) for each generation resource: the calculation of the main Figures of Economic Merit (NPV, IRR, Discounted Payback, the equilibrium price of generated energy and relevant demand for working capital), (iii) measures of energy economy: the calculation of the main Figures of Economic Merit (Annualized Life Cycle Cost (ALCC) and Payback Discounted (PBD), (iv) points of remarkable sensitivity in the Figures of Economic Merit analysis, obtained by varying the main independent parameters input in the cash flow models that represent the resources, (v) analysis of the risks in adoption of the evaluated resources, and finally, (vi) the attractiveness degree of each resources evaluated : not attractive, attractive with attention, and attractive. Within the context of the pilot study case, the use of compact fluorescent bulb received the degree attractive; biomass cogeneration (BIO) and solar collector received degree attractive, but under attention; wind generation (EOL) and PCH received the degree not attractive for investment within the study case region.
157

[en] DEMAND CHARGE FOR LOW VOLTAGE CONSUMERS IN BRAZIL: IMPACTS AND CRITICAL ANALYSIS / [pt] TARIFA BINÔMIA PARA CONSUMIDORES DE BAIXA TENSÃO NO BRASIL: IMPACTOS E ANÁLISE CRÍTICA

FLÁVIA SILVEIRA DE AZEVEDO 20 February 2019 (has links)
[pt] Nos últimos anos tem se verificado um papel mais ativo do pequeno consumidor com relação ao uso da energia elétrica. O acesso mais facilitado às tecnologias de geração distribuída, principalmente produção local fotovoltaica em telhados de residências e também às novas gerações de medidores inteligentes, despertou o interesse de pequenos consumidores para gerar sua própria energia, reduzindo sua fatura com a distribuidora e também sua dependência da rede de distribuição. Nesse contexto, o objetivo da dissertação é avaliar, com base em medições inteligentes reais, o impacto nas faturas de consumidores residenciais causado pela introdução de uma Tarifa de Uso do Sistema de Distribuição, em reais/quilowatt, aplicada sobre a demanda máxima registrada. A opção pelo tema buscou atender lacunas na bibliografia nacional por tratar-se de um assunto inovador, não só no Brasil, e que está sendo estudado em diversos países no mundo simultaneamente. A metodologia pode ser dividida, basicamente, em quatro fases: (i) Apuração da receita de referência; (ii) Cálculo das tarifas de distribuição nas modalidades horária e em reais/quilowatt; (iii) Cálculo e avaliação das receitas obtidas pela aplicação das tarifas às medições dos clusters de estudo; e (iv) Cálculo e avaliação das receitas obtidas pela aplicação das tarifas às medições dos clusters de estudo, considerando geração fotovoltaica distribuída. Os resultados permitiram identificar os perfis de consumo que seriam mais impactados pela introdução de uma tarifação sobre a demanda e também os efeitos resultantes da instalação de painéis solares nas residências, assim demonstrar que essa modalidade de tarifação, ao refletir os custos da atividade de distribuição de energia, propicia estabilidade das tarifas e evita subsídios cruzados. / [en] In recent years there has been a more active role of small consumers in relation to the use of electricity. The easier access to distributed generation technologies, mainly local photovoltaic production in residential roofs and also the new generations of intelligent meters, has brought the interest of small consumers to generate their own energy, reducing their invoice with the distributor and also their dependence on the distribution network. In this context, the objective of this dissertation is to evaluate, based on real smart measurements, the impact on the invoices of residential customers caused by the introduction of a demand charge, in real/kilowatt, applied on the registered maximum demand. The option for the theme sought to address gaps in the national bibliography because it is an innovative subject, not only in Brazil, and which is being studied in several countries simultaneously. The methodology can be divided into basically four phases: (i) Calculation of the reference revenue; (ii) Calculation of distribution tariffs: hourly and based in real/kilowatt; (iii) Calculation and evaluation of the revenues obtained by applying the tariffs to the measurements from the clusters to be studied; and (iv) Calculation and evaluation of the revenues obtained by applying the tariffs to the measurements from the clusters to be studied, considering distributed photovoltaic generation. The results allowed to identify the consumption profiles, whether they would be more impacted by the introduction of a demand charge and the impacts caused by the installation of solar panels by the residences as well as demonstrating that this type of charge, reflecting the costs of distribution, provides tariff stability and avoids cross subsidies.
158

Avaliação da atratividade de negócios em geração distribuída e economia de energia elétrica: piloto aplicado dentro dos estudos de PIR na RAA. / Business attractiveness assessment on distributed generation and measures of energy saving: pilot applied on IRP studies within administrative region of Araçatuba.

Barnabé da Silva Junior 07 May 2012 (has links)
O objetivo da dissertação foi o desenvolvimento de um modelo de avaliação rápida da atratividade de oportunidades de negócios em recursos energéticos renováveis dentro de uma região geográfica delimitada, valendo-se dos resultados do Planejamento Integrado de Recursos Energéticos (PIR) para a região analisada, complementado com outras bases bibliográficas primárias e secundárias. O uso dos resultados do PIR propiciou o acesso rápido a avaliações prontas dos recursos energéticos em três dimensões1, além da dimensão técnico-econômica, incluindo opiniões e posições da sociedade local e nacional (técnicos e não técnicos). No estudo piloto, o modelo é aplicado em cinco recursos energéticos renováveis dentro da Região Administrativa de Araçatuba (RAA), noroeste do estado de São Paulo. Os recursos avaliados são: (a) de oferta: Geração eólica (EOL); Cogeração por Biomassa de Cana-de-açúcar (BIO); e Pequenas Centrais Hidroelétricas (PCH); (b) de demanda (medidas de economia): Troca de Lâmpadas Incandescentes por Fluorescentes Compactas e Troca de Chuveiros Elétricos por Aquecedores Solares. Os principais resultados do modelo de avaliação foram (i) um modelo de fluxo de caixa funcional para a avaliação dos recursos de geração; (ii) para cada recurso de geração: cálculo das principais Figuras de Mérito Econômico Financeiro (VPL, TIR, PayBack Descontado, preço de equilíbrio2 da energia gerada e demanda relevante de capital de giro); (iii) para as medidas de economia de energia: cálculo das figuras de mérito econômico-financeiras (Custo do Ciclo de vida anualizado (CCVA) e PayBack Descontado); (iv) pontos notáveis da análise de sensibilidade das figuras de mérito, obtidas pela variação das principais parâmetros de entrada dos modelos matemáticos representativos dos recursos; (v) análise geral dos riscos em empreender os recursos avaliados; e (vi) diagnóstico da atratividade de investimento em cada recurso: não atrativo, atrativo com atenção, e atrativo. No contexto do estudo piloto, o recurso lâmpada fluorescente recebeu diagnóstico de atrativo; os recursos Cogeração por biomassa e coletor solar receberam o diagnóstico de atrativo com atenção, e os recursos Geração eólica e PCH receberam o diagnóstico de não atrativos para investimento, todos dentro da região do estudo de caso. / The purpose of this work was the expedite assessment of business opportunities attractiveness in renewable energy resources within a limited geographical area, based on the results of the Integrated Resources Planning for Energy (IRP), developed for the same area, and supplemented with other primary and secondary information sources. The use of IRP\'s information made possible, quickly and easy, the assessments of energy resources in extra three dimensions3, beyond the usual technical- economic one, including views and positions of local and national stakeholders (technical and nontechnical). In the pilot study, the model is applied in five renewable energy resources within the Administrative Region of Araçatuba (RAA), northwest of São Paulo state, Brazil. The evaluated energy resources were: (a) supply side: wind generation (EOL); Cogeneration by Biomass of Sugar Cane (BIO); and Small Hydro Power plants (SHP); (b) demand side (measures of energy economy): replacement of Compact Fluorescent Incandescent bulbs by Fluorescent ones and replacement of Electric Showers by Solar Heater ones. The main results of the proposed evaluation model were (i) a functional cash flow model , useful to assess the generation resources; (ii) for each generation resource: the calculation of the main Figures of Economic Merit (NPV, IRR, Discounted Payback, the equilibrium price of generated energy and relevant demand for working capital), (iii) measures of energy economy: the calculation of the main Figures of Economic Merit (Annualized Life Cycle Cost (ALCC) and Payback Discounted (PBD), (iv) points of remarkable sensitivity in the Figures of Economic Merit analysis, obtained by varying the main independent parameters input in the cash flow models that represent the resources, (v) analysis of the risks in adoption of the evaluated resources, and finally, (vi) the attractiveness degree of each resources evaluated : not attractive, attractive with attention, and attractive. Within the context of the pilot study case, the use of compact fluorescent bulb received the degree attractive; biomass cogeneration (BIO) and solar collector received degree attractive, but under attention; wind generation (EOL) and PCH received the degree not attractive for investment within the study case region.
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Méthodes d'optimisation et de gestion de l’énergie dans les réseaux intelligents "Smart Grids" / Optimization methods and energy management in "smart grids"

Melhem, Fady Y. 12 July 2018 (has links)
Les réseaux électriques actuels connaîtront un profond changement dans les années à venir. La nouvelle génération est le Smart Grid (SG) ou le réseau électrique intelligent qui se caractérise par une couche d'information et de communication qui permet aux différents composants du réseau de communiquer. Il doit considérer tous les aspects du réseau électrique, le rendant plus intelligent et flexible. Cette notion est présentée comme une réponse à l'évolution du marché de l'électricité, visant à gérer l’augmentation de la demande tout en assurant une meilleure qualité de service et plus de sécurité.Premièrement, nous présentons une formulation de programmation linéaire mixte en entier pour optimiser les systèmes de production et de consommation d'énergie dans une maison intelligente avec un déploiement efficace de plusieurs ressources énergétiques distribuées. Ensuite, à travers la conception d'expériences avec la méthode de Taguchi, divers scénarios sont introduits en faisant varier des facteurs significatifs. Par la suite, une technique heuristique est proposée pour résoudre le problème de la gestion de l'énergie résidentielle en trouvant la solution optimale globale pendant plusieurs jours consécutifs avec une réduction significative du temps d'exécution.Deuxièmement, un modèle de gestion de l'énergie est assuré grâce à des modèles mathématiques pour optimiser l’utilisation du réseau, des ressources énergétiques renouvelables, des véhicules électriques et de la batterie, ainsi que pour différents types d'appareils thermiques et électriques. Une méthode de solution exacte est mise en œuvre pour réduire le coût de l'électricité dans une maison intelligente et pour trouver des modes de fonctionnement de différentes charges. Ensuite, un algorithme d'optimisation math-heuristique est proposé pour résoudre le problème avec un temps de simulation étendu.Enfin, nous étudions le problème de gestion de l'énergie dans un microréseau constitué de plusieurs maisons intelligentes. Chacune d'elles dépose de ressources énergétiques renouvelables, d’un véhicule électrique et d’appareils intelligents. Les ressources d'énergie renouvelable injectent l’excès de l'énergie dans un système de stockage d'énergie partagé. Un modèle mathématique linéaire mixte en entier pour la gestion d'énergie est proposé pour réduire le coût total de fonctionnement du microréseau. Des comparaisons avec des scénarios conventionnels où chaque maison intelligente possède son propre système de stockage d'énergie sont effectuées pour démontrer l’efficacité de la démarche proposée. / The current electricity grids will experience a profound change in the coming years. The new generation is the Smart Grid (SG) which is characterized by information and communication layer enabling the communication between the different components of the grid. It needs to consider all sides of power grid, making it more intelligent and flexible. This notion is presented as an answer to changes in the electricity market, aiming to manage the increased demand while ensuring a better quality of service and more safety.First, we present a mixed integer linear programming formulation to optimize the energy production and consumption systems in a smart home with an effective deployment of several distributed energy resources. Then through the design of experiments with the Taguchi method, diverse scenarios are introduced by varying significant factors. Afterward, a heuristic technique is proposed to solve the problem of residential energy management by finding the global optimum solution for many consecutive days with significant reduction of execution time.Second, an energy management model is proposed thanks to mathematical models to optimize the grid, renewable energy resources, battery and electric vehicles are presented as well as for different type of thermal and electrical appliances. An exact solution method is implemented to reduce the electricity cost in a smart home and find out operation modes of different loads. Then a math-heuristic optimization algorithm is proposed to solve the problem with extended simulation time horizon.Finally, we study a microgrid energy management problem which comprises multiple smart homes. Each of them owns renewable energy resources, one electric vehicle and smart appliances. The renewable energy resources inject the excess energy in the shared energy storage system. An optimized energy management model using mixed integer linear programming is proposed to reduce the total electricity cost in the microgrid. Comparisons with conventional scenarios where each smart home has its individual small energy storage system without sharing energy with their neighbors are done to ensure that the proposed formulation is well efficient.
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Efficient Simulation Methods of Large Power Systems with High Penetration of Renewable Energy Resources : Theory and Applications

Shayesteh, Ebrahim January 2015 (has links)
Electrical energy is one of the most common forms of energy these days. Consequently, electric power system is an indispensable part of any society. However, due to the deregulation of electricity markets and the growth in the share of power generation by uncontrollable renewable energies such as wind and solar, power system simulations are more challenging than earlier. Thus, new techniques for simplifying these simulations are needed. One important example of such simplification techniques is the power system reduction. Power system reduction can be used at least for four different purposes: a) Simplifying the power system simulations, b) Reducing the computational complexity, c) Compensating the data unavailability, and d) Reducing the existing uncertainty. Due to such reasons, power system reduction is an important and necessary subject, but a challenging task to do. Power system reduction is even more essential when system operators are facing very large-scale power systems and when the renewable energy resources like hydro, wind, and solar have a high share in power generation. This thesis focuses on the topic of large-scale power system reduction with high penetration of renewable energy resources and tries to pursue the following goals: • The thesis first reviews the different methods which can be used for simplifying the power system studies, including the power system reduction. A comparison among three important simplification techniques is also performed to reveal which simplification results in less error and more simulation time decrement. • Secondly, different steps and methods for power system reduction, including network aggregation and generation aggregation, are introduced, described and discussed. • Some improvements regarding the subject of power system reduction, i.e. on both network aggregation and generation aggregation, are developed. • Finally, power system reduction is applied to some power system problems and the results of these applications are evaluated. A general conclusion is that using power system simplification techniques and specially the system reduction can provides many important advantages in studying large-scale power systems with high share of renewable energy generations. In most of applications, not only the power system reduction highly reduces the complexity of the power system study under consideration, but it also results in small errors. Therefore, it can be used as an efficient method for dealing with current bulk power systems with huge amounts of renewable and distributed generations. / <p>The Doctoral Degrees issued upon completion of the programme are issued by Comillas Pontifical University, Delft University of Technology and KTH Royal Institute of Technology. The invested degrees are official in Spain, the Netherlands and Sweden, respectively. QC 20150116</p>

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