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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.
121

Integrated Community Energy Systems

Koirala, Binod Prasad January 2017 (has links)
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
122

Energy System Modeling towards a Sustainable Future

Yiru Li (8804120) 12 October 2021 (has links)
<div>As the global population approaches 10 billion by the mid-century, supplying all the needs of the human race from the Earth’s limited land area and resources with minimized greenhouse gas emission will be the essential challenge of sustainability. In a sustainable economy, all renewable energy, in combination with carbon sources and other elements from the nature, such as water, air and land, will be used synergistically to produce building blocks for human beings. These building blocks, including electricity, heat, fuels, hydrogen, etc., will enable the production of all the end uses for human beings. The challenge for chemical engineers is to come up with processes and synergistic strategies to enable such a sustainable future.</div><div><br></div><div>Shale gas can serve as both energy resource and chemical feedstock for the transition period towards a sustainable economy, and has the potential to be a carbon source for the long term. Natural gas liquids contained in shale gas provide abundant feedstock for chemical and fuel production and could bring extra value for remote shale gas basins. Unlike current shale gas processing where large scales are preferred, simple and intensified processes with least processing steps and least pieces of equipment are favored for remote shale plays. While conventional shale gas processing usually follows a four-section hierarchy of "gas treatment - NGL recovery - NGL fractionation - NGL activation", four innovative configurations are proposed for simpler and intensified process design, including NGL co-processing, integrated NGL recovery and activation, switched NGL recovery and activation, and eliminated NGL recovery. A two-step conversion of NGLs to liquid hydrocarbons via dehydrogenation followed by oligomerization is used as an example to show how these innovative process designs evolve. Simulation results show that the loss of ethane, the NGL component with the highest concentration, could be largely reduced by the innovative process configurations. At the same time, higher yield of liquid products, fewer processing steps, reduced pieces of equipment and elimination of energy and capital-intensive units can be achieved. The intensification of process here would benefit the modularization of shale gas plants, and make it possible for distributed production of liquid hydrocarbons onsite for remote shale locations. </div><div><br></div><div>While shale gas being the carbon source for a sustainable future, renewable energy, especially solar and wind energy, will become the dominant energy resources for a sustainable economy. However, both solar and wind energy are dilute resources and harvesting them requires vast tracts of land, which could potentially compete with agricultural production for food. As a bookend case study, we investigate the land requirement for a 100% solar economy. The contiguous United States is used as an example and our analysis takes into account several issues that are usually ignored, such as the intermittent solar availability, estimation of future energy demand, actual power production from solar farms and available land types. Results show that it will be difficult for currently available land to meet the energy needs using current solar park designs for the entire contiguous United States and for nearly half of the individual states, which include well over half of the total US population. Barring radical improvements in agricultural output that could greatly reduce the land devoted to agriculture, the competition for land between energy and food seems inevitable, posing a major challenge to a future solar economy. If we extend the study to Germany, the United Kingdom and China, we could see that the challenge exists for both developed and developing countries. </div><div><br></div><div>To resolve the issue, a concept of "Aglectric" farming is proposed, where agricultural land produces electricity without diminishing existing agricultural output. Both wind turbines and photovoltaic (PV) panels can be used to generate electricity on agricultural land. While the use of the current PV panels is known to have a negative impact on crop growth, we propose several innovative PV systems using existing and new materials, innovative installation paradigms and module designs. Through extensive modeling of PV shadows throughout a day, we show that some of our designed PV systems could mitigate the loss of solar radiation while still maintaining substantial power output. Thus, it should be possible to design and install these PV systems on agricultural land to have significant power output without potentially diminishing agricultural production. We also show that PV aglectric farms alone will have the potential of realizing a 100% solar economy without land constraint. Together with regular PV parks and wind aglectric farms, PV aglectric farms will serve as an important option for a renewable future.</div><div><br></div><div>With its high energy density and zero greenhouse gas emission, hydrogen is the key energy carrier in a sustainable future. We introduce a process design strategy for the production of hydrogen by high temperature water electrolysis using concentrated solar thermal energy. At the same time, co-production of hydrogen and electricity is investigated where hydrogen can be produced by both thermochemical cycles and high temperature electrolysis. The process design features the process integration between hydrogen production and power generation. Process simulation is performed in an integrated Matlab and Aspen Plus platform. Efficiencies are analyzed for various processes.</div><div><br></div><div>Synergy is the key feature of all the studies in the dissertation. Process intensification for shale gas conversion and process integration for solar hydrogen production are examples of synergy at the process level. Coproduction of hydrogen and electricity and coproduction of electricity and food are examples of synergy at the building block level. Potential synergistic use of solar, wind and shale resources is an example of synergy at the resource level. Synergy is the keyword of the sustainable future we are pursuing.</div>
123

Factors Affecting The Adoption Of Automated Wood Pellet Heating Systems In The Northeastern Us And Implications For The Transition To Renewable Energy

Edling, Laura 01 January 2020 (has links)
Public and private incentive programs have encouraged conversions to high efficiency, low emissions wood heating systems as a strategy to promote renewable energy and support local economies in the Northeastern US. Despite these efforts, the adoption of these systems remains slow. The study that is the subject of this dissertation examines several social, economic, policy and environmental factors that affect the decisions of individuals and small-scale institutions (local business and community facilities) to transition to automated wood pellet boilers and furnaces (AWPH) utilizing local fuel sources. Due to the complexity and risk associated with conversion, the transition to these systems can help further both a practical and theoretical understanding of the global transition to non-fossil fuel technologies. Chapter One of this dissertation examines this notion in more detail, as well as spells out the research questions of this study. Chapter Two delves into the research methods and their implications for other studies of energy transitions. These methods include interviews with 60 consumers, technology and fuel suppliers, and NGO and state agency personnel. These provided in-depth qualitative data which are complemented by a four-state survey (New Hampshire, Vermont, New York, and Maine) of adopters and informed non-adopters of AWPH systems (n=690; 38% response rate). Interview and survey questions, as well as subsequent coding, was developed through use of diffusion of innovation theory, the multi-level perspective on sociotechnical transitions, as well as through collaboration with industry experts and research partners. Chapters Three and Four offer a discussion of the results and their implications. Specifically, Chapter Three examines the complex system actors, elements, and interactions that are part of the transition from fossil fuel technology to AWPH. Chapter Four focuses on the data surrounding state and private programs that encourage the use of AWPH and the implications that this data has for effective climate mitigation and energy policy. Data show that AWPH consumers, who should be considered “early adopters” due to the small number of AWPH adopters in the region, are largely value-driven but are also concerned about upfront costs and lack of available technical support and fuel delivery options. Both environmental values (e.g. desire to find alternative to fossil fuels, concern for air quality and belief in climate change) and social values (e.g. support for the local economy and wood products industry) influenced consumer decisions, especially when fuel oil prices were low. Financial incentives, which are offered by all four states in the study region, were highly influential, but additional decision support offered by a non-profit (e.g. site visits, informational workshops, local print media) were rated highly by consumers where they were available. These additional supports, as well as the community-based nature of the non-profit program, enabled a broader range of people (lower income, more risk averse) to choose AWPH as well as created more efficiency in the supply chain. This approach created a reinforcing feedback loop between broader early adopters of AWPH, normalization of AWPH technology and its associated infrastructure, and increased levels of technical support and fuel availability. These findings suggest that efforts to increase adoption of renewable technologies that use locally harvest fuels take a community-based and system-wide approach, targeting both consumer and supplier motivations and barriers.
124

Ökonomische Bewertung von innovativen Speichertechnologien in Energiesystemen mit einem hohen Anteil erneuerbarer Energien

Kondziella, Hendrik 09 February 2017 (has links)
Diese Arbeit geht der Frage nach, ob sich durch die stattfindende Transformation zu einem kohlenstoffarmen Energiesystem in Deutschland auch Marktchancen für innovative Marktteilnehmer, insbesondere für Speicherbetreiber, herausbilden. Die ökonomischen Effekte, die in Energiesystemen mit hohen Anteilen an variablen erneuerbaren Energien (vEE) auftreten, können durch deren Integrationskosten gemessen werden. Die wissenschaftlichen Untersuchungen in Bezug auf den zusätzlichen Speicher- bzw. Flexibilitätsbedarf für ein solches Energiesystem setzen häufig bei den Ungleichgewichten in der Systembilanz an. Den jeweiligen Methoden liegen jedoch unterschiedliche Annahmen und Rahmenbedingungen zu Grunde, sodass die Ergebnisse nur eingeschränkt miteinander verglichen werden können. Der stündlich schwankende Großhandelspreis an der Strombörse ist ein wichtiger Indikator, um den Flexibilitätsbedarf zu signalisieren. Viele Analysen legen historische oder auch prognostizierte Preiszeitreihen für eine Bewertung von Speicheroptionen zu Grunde. Jedoch wird dabei die Rückkopplung der Betriebsweise eines Energiespeichers auf die Marktpreise außen vor gelassen. In dieser Arbeit wird deshalb eine Methode entwickelt, um den Einfluss eines steigenden Marktvolumens an Speichern und anderen Flexibilitätsoptionen auf die Spotmarktpreise abzuschätzen. Untersucht wird der Einfluss des Speichereinsatzes auf die Stromnachfrage und die Spotmarktpreise in 2020 sowie 2030. Die hierfür zu definierenden Szenarien für den Strommarkt werden modellgestützt abgebildet und ausgewertet. Für die Beantwortung der Fragestellung werden techno-ökonomische Modelle, z.B. das Strommarktmodell MICOES zur Kraftwerkseinsatzplanung, das Modell DeSiflex zur Glättung der Residuallast durch integrierte Flexibilitätsoptionen sowie das Modell Arturflex zur Abschätzung der Arbitragegewinne durch Einsatz von Flexibilitätsoptionen am Spotmarkt, herangezogen.
125

Electricity, Heat, and Gas Sector Data for Modeling the German System

Kunz, Friedrich, Kendziorski, Mario, Schill, Wolf-Peter, Weibezahn, Jens, Zepter, Jan, von Hirschhausen, Christian, Hauser, Philipp, Zech, Matthias, Möst, Dominik, Heidari, Sina, Felten, Björn, Weber, Christoph January 2018 (has links)
Diese Dokumentation beschreibt Daten zum deutschen Strom- Wärme- und Gassektor und ermöglicht eine modellgestützte Abbildung dieser Energiesysteme. Die Aufbereitung der Daten erfolgte im Rahmen des vom BMWi geförderten Forschungsprojekts LKD-EU (Langfristige Planung und kurzfristige Optimierung des Elektrizitätssystems in Deutschland im europäischen Kontext, FKZ 03ET4028C). In Zusammenarbeit mit dem Deutschen Institut für Wirtschaftsforschung (DIW), der Arbeitsgruppe Wirtschafts- und Infrastrukturpolitik (WIP) der Technischen Universität Berlin (TUB), dem Lehrstuhl für Energiewirtschaft (EE2), der Technischen Universität Dresden (TUD) und dem House of Energy Markets & Finance der Universität Duisburg-Essen (UDE). Ziel des Dokumentes ist es, Referenzdaten zur Verfügung zu stellen, die den aktuellen Zustand des deutschen Energiesystems repräsentieren. Das Bezugsjahr ist 2015. Diese Dokumentation trägt dazu bei, die Transparenz in der Verfügbarkeit von Daten zum deutschen Energiesystem zu erhöhen. / This data documentation describes a data set of the German electricity, heat, and natural gas sectors compiled within the research project ‘LKD-EU’ (Long-term planning and short-term optimization of the German electricity system within the European framework: Further development of methods and models to analyze the electricity system including the heat and gas sector). The project is a joined effort by the German Institute for Economic Research (DIW Berlin), the Workgroup for Infrastructure Policy (WIP) at Technische Universität Berlin (TUB), the Chair of Energy Economics (EE2) at Technische Universität Dresden (TUD), and the House of Energy Markets & Finance at University of Duisburg-Essen. The project was funded by the German Federal Ministry for Economic Affairs and Energy through the grant ‘LKD-EU’, FKZ 03ET4028A. The objective of this paper is to document a reference data set representing the status quo of the German energy sector. We also update and extend parts of the previous DIW Data Documentation 75 (Egerer et al. 2014). While the focus is on the electricity sector, the heat and natural gas sectors are covered as well. With this reference data set, we aim to increase the transparency of energy infrastructure data in Germany. On the one hand, this documentation presents sources of original data and information used for the data set. On the other hand, it elaborates on the methodologies which have been applied to derive the data from respective sources in order to make it useful for modeling purposes and to promote a discussion about the underlying assumptions. Furthermore, we briefly discuss the underlying regulations with regard to data transparency in the energy sector. Where not otherwise stated, the data included in this report is given with reference to the year 2015 for Germany.
126

Modeling and Optimizing of Integrated Multi-Modal Energy Systems for Municipal Energy Utilities

Scheller, Fabian 05 June 2019 (has links)
The development of sustainable business models is a challenging task since various factors might influence the results of an assessment. Given the complexity at the municipal level, system interdependencies between different alternatives need to be considered. One possibility to support decision makers is to apply energy system optimization models. Existing optimization models, however, ignore the roles different actors play and the resulting impact they have. To address this research issue, this thesis presents an integrated techno-economic optimization framework called IRPopt (Integrated Resource Planning and Optimization). A proven graph-based energy system approach allows the accurate modeling of deployment systems by considering different energy carriers and technical processes. In addition, a graph-based commercial association approach enables the integration of actor-oriented coordination. This is achieved by the explicit modeling of market actors on one layer and technology processes on another layer as well as resource flow interrelations and commercial agreements mechanism among and between the different layers. Using the optimization framework, various optimization problems are solvable on the basis of a generic objective function. For demonstration purposes, this thesis assesses the business models demand response and community storage. The applied examples demonstrate the modeling capabilities of the developed optimization framework. Further, the dispatch results show the usefulness of the described optimization approach.
127

Estimation of possibility to implement fuel cell technology for decentralized energy supply in Russia

Sveshnikova, Aleksandra January 2015 (has links)
Industrial power generation is an ever-changing practice. After the steam turbine was invented energy production developed with accelerated tempo. Coal replaced wood, oil replaced coal and after natural gas started being used as an energy source, no one could even imagine better and cleaner energy technologies. But in the 21st century renewable energy started its development. The western world decided to develop green, environmentally friendlier technologies with a strong desire to become independent form oil and gas exporters. Hydrogen energy and fuel cell technology are two of the most promising fields of energy study. The European Union and the USA regularly invest a lot of money for research in this area and rapidly develop an energy economy that is free from CO2 emissions. In this scientific report, the situation of hydrogen energy systems in the world but also with a large focus on Russia has been investigated. The main focus was made on successful international projects which have been created within last decades. Moreover, hydrogen production methods and fuel cell technology were described in detail. The cost to produce 1 kg of hydrogen gas based off of Russian economic figures and using water electrolysis and steam reforming process was estimated. Solid oxide and polymer electrolyte membrane fuel cells were considered in the analysis. The next step was to estimate effectiveness of combined technology with electrical power of 1 kW and economic feasibility of using such technology as stand-alone power generation system in the regions with decentralized electricity.
128

Flexibility Options in Energy Systems: The influence of Wind - PV ratios and sector coupling on optimal combinations of flexible technologies in a European electricity system

Zöphel, Christoph 01 March 2022 (has links)
Within the present work, the main objective is to identify interactions between flexibility demand and flexibility supply. Therefore, three research fields regarding the future transformation of the European energy system are addressed. First, an expansion of intermittent renewable energy sources (iRES) is discussed taking the potentials of wind and PV technologies into account. The analysis is based on fundamental considerations of generation characteristics as well as available potentials across 17 countries in central-western Europe. To emphasis the differences in electricity generation between wind and PV, an iRES expansion model is developed coping for geographically highly resolved weather data as well as for limitations of iRES potentials due to land-use restrictions and for energy-policy constraints. Three scenarios with varying Wind-PV ratio in total iRES electricity generation are evaluated. Second, the options to provide flexibility to balance the flexibility demand are introduced and mathematically implemented in ELTRAMOD. Therefore, the model was adjusted to represent multiple flexible technologies for upward, downward and shifting flexibility provision to cover the residual load. In a system perspective and a greenfield approach, the linear electricity market model enables the analysis of cost-optimal combinations of flexibility options against the background of scenarios with different flexibility demands. In addition, the third research field addresses the emerging developments of sector coupling by including selected Power-to-X technologies. A second scenario dimension analyses the role of energy storages in the energy end-use sectors for a more flexible sector coupling. The results underline the importance of the Wind-PV ratios in electricity generation when assessing flexibility demand and flexibility supply in model-based energy system analysis. Due to the higher seasonality of PV, the residual load parameter indicate higher iRES integration challenges in terms of flexible capacity requirements. Particularly the provision of spatial and temporal balancing flexibility is significantly influenced by a higher wind or a higher PV share in the iRES mix. With sector coupling, the value of temporal shifting is increasing. Hourly storages are not only highly sensitive to the Wind-PV ratio, but in addition strongly impacted by sector coupling. In both dimensions, a higher PV share is increasing the value for short-term shifting. Furthermore, sector coupling increases the need for additional electricity generation. Thereby, for peak-load capacity provision gas-fuelled power plant are optimal in the present work increasing the total emissions especially with higher PV shares. The sensitivity analysis shows the value of additional iRES capacities as well as of storage cost reductions to further reduce emissions.
129

Demand Side Management in Deutschland zur Systemintegration erneuerbarer Energien

Ladwig, Theresa 10 July 2018 (has links)
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.
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P2P Electricity transaction between DERs by Blockchain Technology

Liu, Ruogu January 2018 (has links)
The popularity of blockchain technologies increases with a significant rise in the price of cryptocurrency in 2017, which drew much attention in the academia and industry to research and implement new application or new blockchain technology. Many new blockchains have emerged over the last year in a broad spectrum of sectors and use cases including IOT, Energy, Finance, Real estate, Entertainment, etc.Despite many exciting research and applications have been done, there are still many areas worth investigating, and implementation of the blockchain based distributed application are still facing much uncertainty and challenging since blockchain is still an emerging technology. Meanwhile, the energy sector is under a transition to be digitalized and more distributed. A global technology revolution has disrupted the conventional centralized power system with distributed resources and technologies, like photovoltaic units (PV), batteries, electric mobilities, etc. The citizens then have control of their generation and consumption profiles.The purpose of this master thesis is to explore existing blockchain technology, and smart contracts such as IOTA, NEO, Ethereum Tobalaba, which can be adapted in the energy sector. Within this thesis, blockchain and the smart contract is proposed as a way of building distributed applications for a p2p transaction use case in the energy asset management platform. A design science research methodology is applied for the artifact development and evaluation for the research result. The design was implemented on Ethereum and tested on Tobalaba public network with ether and GAS. The evaluation shows the artifact for the p2p transaction in energy asset management platform fulfill the completeness, and correctness of the design requirement. The result of the performance test on Tobalaba networks shows a correlation between GAS consumption and transaction time.

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