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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Distributed Renewable Energy Generation and Landscape Architecture: A Critical Review

Beck, Osmer DeVon 01 May 2010 (has links)
Governments and utility organizations around the world have mandated and provided incentives for new distributed renewable energy generation (DREG) capacity, and market projections indicate strong growth in distributed renewable energy generation installations in the coming years. New distributed renewable energy generation utilities, by definition, will be primarily located in built environments near consumers; these utilities are often planned and designed by landscape architects, yet no evidence-based, distributed renewable energy generation research is explicitly done by landscape architects or recognizes the role landscape architects play in planning and designing these spaces. The research and analysis provided by this study indicates that distributed renewable energy generation lacks a strong foundation as an independent concept which could benefit from clear broad phraseology linked to organized sub-terms/phrases for specific forms of DREG, that there has been some research done on topics familiar to landscape architects, that more needs to be done to meet important research questions and recommendations already posed, and that landscape architects are positioned to contribute to future distributed renewable energy generation research.
2

Large-scale Solar PV Investment Planning Studies

Muneer, Wajid January 2011 (has links)
In the pursuit of a cleaner and sustainable environment, solar photovoltaic (PV) power has been established as the fastest growing alternative energy source in the world. This extremely fast growth is brought about, mainly, by government policies and support mechanisms world-wide. Solar PV technology that was once limited to specialized applications and considered very expensive, with low efficiency, is becoming more efficient and affordable. Solar PV promises to be a major contributor of the future global energy mix due to its minimal running costs, zero emissions and steadily declining module and inverter costs. With the expanding practice of managing decentralized power systems around the world, the role of private investors is increasing. Thus, the perspective of all stakeholders in the power system, including private investors, has to be considered in the optimal planning of the grid. An abundance of literature is available to address the central planning authority’s perspective; however, optimal planning from an investor’s perspective is not widely available. Therefore, this thesis focuses on private investors’ perspective. An optimization model and techniques to facilitate a prospective investor to arrive at an optimal investment plan in large-scale solar PV generation projects are proposed and discussed in this thesis. The optimal set of decisions includes the location, sizing and time of investment that yields the highest profit. The mathematical model considers various relevant issues associated with PV projects such as location-specific solar radiation levels, detailed investment costs representation, and an approximate representation of the transmission system. A detailed case study considering the investment in large-scale solar PV projects in Ontario, Canada, is presented and discussed, demonstrating the practical application and usefulness of the proposed methodology and tools.
3

Large-scale Solar PV Investment Planning Studies

Muneer, Wajid January 2011 (has links)
In the pursuit of a cleaner and sustainable environment, solar photovoltaic (PV) power has been established as the fastest growing alternative energy source in the world. This extremely fast growth is brought about, mainly, by government policies and support mechanisms world-wide. Solar PV technology that was once limited to specialized applications and considered very expensive, with low efficiency, is becoming more efficient and affordable. Solar PV promises to be a major contributor of the future global energy mix due to its minimal running costs, zero emissions and steadily declining module and inverter costs. With the expanding practice of managing decentralized power systems around the world, the role of private investors is increasing. Thus, the perspective of all stakeholders in the power system, including private investors, has to be considered in the optimal planning of the grid. An abundance of literature is available to address the central planning authority’s perspective; however, optimal planning from an investor’s perspective is not widely available. Therefore, this thesis focuses on private investors’ perspective. An optimization model and techniques to facilitate a prospective investor to arrive at an optimal investment plan in large-scale solar PV generation projects are proposed and discussed in this thesis. The optimal set of decisions includes the location, sizing and time of investment that yields the highest profit. The mathematical model considers various relevant issues associated with PV projects such as location-specific solar radiation levels, detailed investment costs representation, and an approximate representation of the transmission system. A detailed case study considering the investment in large-scale solar PV projects in Ontario, Canada, is presented and discussed, demonstrating the practical application and usefulness of the proposed methodology and tools.
4

Off-grid portable production and distribution of sustainable energy : A product service system solution developed for the energy market

Andersson, Karl-Henrik, Liedman, Stefan January 2022 (has links)
Background. At the year of 2021, 770 million people worldwide were living without access to electricity. In parallel with this, electrification of vehicles and other equipment constantly increases which results in a demand for access to reliable off-grid energy to allow for operation in remote locations or places without sufficient energy infrastructure due to external factors such as natural disasters. As the use of fossil fuels is predicted to decrease, the need for sustainable energy production utilizing renewable energy sources has proved to be critical. The combination of these factors results in a need for the development of sustainable off-grid energy systems utilizing renewable energy sources.  Objectives. The objective of this thesis is to highlight needs and present a developed solution to portable off-grid energy production and distribution utilizing renewable energy sources. The goal is to highlight problems within the area of focus and present a potential solution to one, or multiple, of these problems. The presented solution shall be based on a solid engineering foundation and meet the technical requirements developed from needs that arise during the project. Methods. The work presented in this thesis was conducted with the use of DRM, Design Research Methodology, as the choice of research methodology while Design thinking was the choice of design approach. The use of DRM allowed for a structured and efficient research process that allowed for the possibility to validate result. The use of Design thinking as design approach provided methods and tools to support innovation while working with problems that were initially unknown or vaguely defined. Results. The result of the work presented in this thesis provides information regarding multiple problems and critical aspects within the area of focus. A list of requirements for a sustainable energy system to satisfy in order to enter the market is presented, where portability, reliability and redundancy are marked as key requirements. A proposed solution in the form of a portable modular sustainable energy production trailer utilizing different renewable energy sources was developed to allow for off-grid electricity generation. This combined with an energy distribution solution in the form of a energy storage module mounted on the Volvo TA15 system allows for autonomous energy transportation to the location of the energy need.  Conclusions. As the need for sustainable energy constantly increases, development of sustainable energy production and distribution systems that can operate off-grid has proven to be critical. The utilization of renewable energy sources has also been identified as a critical factor in parallel with the phasing out of fossil fuels. The proposed solution has provided evidence of the potential for a portable off-grid hybrid energy system and its potential impact on the global 2030-agenda goals for sustainability.
5

Boat-shaped Buoy Optimization of an Ocean Wave Energy Converter Using Neural Networks and Genetic Algorithms

Lin, Weihan 19 January 2023 (has links)
The point absorber is one of the most popular types of ocean wave energy converter (WEC) that harvests energy from the ocean. Often such a WEC is deployed in an ocean location with tidal currents or ocean streams, or serves as a mobile platform to power the blue economy. The shape of the floating body, or buoy, of the point absorber type WEC is important for the wave energy capture ratio and for the current drag force. In this work, a new approach to optimize the shape of the point absorber buoy is developed to reduce the ocean current drag force on the buoy while capturing more energy from ocean waves. A specific parametric modeling is constructed to define the shape of the buoy with 12 parameters. The implementation of neural networks significantly reduces the computational time compared to solving hydrodynamics equations for each iteration. And the optimal shape of the buoy is solved using a genetic algorithm with multiple self-defined functions. The final optimal shape of the buoy in a case study reduces 68.7% of current drag force compared to a cylinder-shaped buoy, while maintaining the same level of energy capture ratio from ocean waves. The method presented in this work has the capability to define and optimize a complex buoy shape, and solve for a multi-objective optimization problem. / Master of Science / The marine kinetic energy includes ocean waves power, tidal power, ocean current power, ocean thermal power and river power. The total potential marine kinetic energy in 2021 is 2300 TWh/year, where 1400 TWh/year is from the ocean wave power. To discover and harvest the huge potential power from the marine, researchers have been developed for different types of WECs for several decades. One of the most successful concepts is the point absorber typed WEC, which can extract waver energy from the heaving vibration motion of a floating body and convert the kinetic energy into electrical energy. This thesis presents an optimization strategy to optimize the shape of the floating body to improve power extraction and reduce the installation cost by implementing the machine learning tool and genetic algorithm. Compared with the state-of-the-art optimization strategies, the proposed optimization method allows the floating body to have more parameters in shape changes and reduces the computational cost from minutes to milliseconds. The final optimized floating body shape performs extraordinarily compared to the other two state-of-the-art floating body shapes.
6

Investments in Academic Renewable Electricity Generation Technology Spin-Offs : A Qualitative Study on High Capital Limitations for Underexplored Renewable Energy Sources

Braune, Yann January 2020 (has links)
Due to an intensified climate change discourse, renewable energy technologies find higher attention within the energy system and increasingly compete with traditional energy conversion systems. Electricity is progressively being generated through renewable electricity generation technologies (REGT) which harness naturally existing energy fluxes (wind, tide, heat, sun) and convert it to electricity. High investments are currently being made into well-developed REGT using explored energy sources such as wind, hydro or solar. In order to increase cost- and energy efficiency of REGTs, university research projects are developing new REGTs that harvest underexplored energy sources such as the marine energy source. These capital-intensive marine energy research projects are entering the market through university spin-off firms but are often confronted with funding gaps, for the current or future operations. Capital rich investors could provide these funds but are often investing in well explored energy sources rather than into underexplored but more cost- and energy-efficient energy sources. Utilizing a qualitative, grounded theory-influenced approach and combining empirical material of semi-structured interviews, data from a participant observation of an innovation system workshop attendance and data from continuous meetings with an academic REGT spin-off from Uppsala University, this study investigates 1) the drivers and barriers within the funding ecosystem for academic REGT spin-offs in Sweden, 2) the limited access of high capital to underexplored energy sources on the specific case of the marine energy source and 3) a potential common ground for investors with high capital and academic REGT spin-offs in order to allow an accelerated diffusion of the marine energy source. The results indicate that the physical properties of the underexplored marine source should not be accounted for as driver but rather as the foundation of an academic REGT spin-off. This frame allows to bridge practitioners of both the investment field and the academic field of REGT spin-offs through the degree of utilization. An inversion of relations, where not only entrepreneurs increasingly link their field of study to economy and business, but also investors adapt cross-disciplinary knowledge towards academia and natural sciences via the degree of utilization, could be beneficial for an accelerated diffusion of academic REGTs. Bridging practitioners of both fields through the degree of utilization and other means might together with a full commercial application and proof of marine REGTs reduce the funding gap of academic spin-offs in the marine sector and allow access to investors with high capital.
7

[en] MODEL FOR SELECTING SITES FOR PUMPED STORAGE IMPLEMENTATION: AN APPROACH BASED ON GEOGRAPHIC INFORMATION SYSTEM / [pt] MODELO PARA SELEÇÃO DE LOCAIS PARA A IMPLANTAÇÃO DE USINAS HIDRELÉTRICAS REVERSÍVEIS: UMA ABORDAGEM BASEADA EM SISTEMA DE INFORMAÇÃO GEOGRÁFICA

LUIZ RODOLPHO SAURET CAVALCANTI DE ALBUQUERQUE 23 June 2022 (has links)
[pt] A recente expansão das fontes renováveis para geração de energia elétrica decorre do encarecimento dos combustíveis fósseis e da preocupação com impactos ambientais e mudanças climáticas, assim como de avanços tecnológicos e da queda de seus custos de implantação. Entretanto, a natureza intermitente e sazonal dos recursos naturais, como vento e irradiação solar, pode afetar a operação do sistema elétrico. Uma alternativa para dar equilíbrio à carga do sistema, proporcionando ainda outros benefícios, é o armazenamento de energia. Uma tecnologia de larga escala para armazenamento é a de bombeamento hidráulico por meio de usinas hidrelétricas reversíveis (UHR), que oferecem mais eficiência, tempo de resposta mais rápido e vida útil mais longa que outras alternativas. Tendo em vista as lacunas teóricas no campo acadêmico, a dissertação propõe um modelo para identificação de locais potenciais para implantação dessas usinas, com o auxílio de ferramentas de sistema de informação geográfica e de formulações matemáticas que consideram critérios fisiográficos, energéticos, econômicos e socioambientais. Partindo de uma abordagem baseada no conceito de geomorphons combinada com soluções de um problema de otimização, o modelo proposto tem por objetivo definir uma formulação que busque minimizar os custos de construção de uma UHR. A demonstração da aplicabilidade do modelo é feita em torno do reservatório da UHE Sobradinho, e os resultados são discutidos a partir da comparação dos locais selecionados e dos custos obtidos. Pode-se concluir que é possível identificar potenciais locais para implantação de UHR a partir desse modelo, o que pode beneficiar agentes de planejamento do setor elétrico, bem como empresas que estejam interessadas em investir nesta tecnologia. / [en] The expansion of the use of renewable sources for electricity generation in recent years is a result of the increase of fossil fuels costs and the growing concern with climate change and the impacts on the environment, as well as technological advances and the reduction in their implementation costs. However, the availability of some natural resources for renewable energy matrices, such as wind and solar irradiation, has an intermittent and seasonal nature, which may affect the electrical system operation (CANALES et al., 2015; KELMAN & HARRISON, 2019). One of the alternatives to balance the system load is energy storage, which offers benefits to the electricity provision (ancillary services, for example) and regulates the frequency in times of high demand with low energy supply from renewables, contributing with the necessary inertia so that demand does not change instantly (BARBOUR et al., 2016). The most widely large-scale technology used for storage in the world is hydraulic pumping through pumped storage hydropower – PSH (GUITTET et al., 2016; IHA, 2018). Compared to other technologies, it provides a solution with high efficiency, faster response time and longer useful life (REHMAN et al., 2015). The operation of the plants is characterized by the pumping of water from a lower reservoir for its accumulation in an upper reservoir for energy generation in periods of high demand (BARBOUR et al., 2016). Energy storage alternatives are already on the agenda in the Brazilian energy sector as an option to ensure the system development in an economic and sustainable manner. In the 2030 Ten-Year Energy Expansion Plan (EPE, 2021b), PSH is highlighted as one of the resources to expand the offer for rush hour demand response. EPE understands that preliminary studies are an important step to support the sector s planning and guide the definition of regulatory aspects, which do not yet exist, related to the systemic benefits of this type of solution.
8

Increasing the hosting capacity of distributed energy resources using storage and communication / Öka acceptansgränsen för förnyelsebaraenergikällor med hjälp av lagring och kommunikation i smarta elnät

Etherden, Nicholas January 2012 (has links)
The use of electricity from Distributed Energy Resources like wind and solar powerwill impact the performance of the electricity network and this sets a limit to theamount of such renewables that can be connected. Investment in energy storage andcommunication technologies enables more renewables by operating the networkcloser to its limits. Electricity networks using such novel techniques are referred toas “Smart Grids”. Under favourable conditions the use of these techniques is analternative to traditional network planning like replacement of transformers orconstruction of new power line.The Hosting Capacity is an objective metric to determine the limit of an electricitynetwork to integrate new consumption or production. The goal is to create greatercomparability and transparency, thereby improving the factual base of discussionsbetween network operators and owners of Distributed Energy Resources on thequantity and type of generation that can be connected to a network. This thesisextends the Hosting Capacity method to the application of storage and curtailmentand develops additional metrics such as the Hosting Capacity Coefficient.The research shows how the different intermittency of renewables and consumptionaffect the Hosting Capacity. Several case studies using real production andconsumption measurements are presented. Focus is on how the permitted amountof renewables can be extended by means of storage, curtailment and advanceddistributed protection and control schemes. / Användningen av el från förnyelsebara energikällor som vind och sol kommer att påverka elnätet, som sätter en gräns för hur mycket distribuerad energiproduktion som kan anslutas. Investeringar i storskalig energilager och användning av modern kommunikationsteknologi gör det möjligt att öka andelen förnyelsebarenergi genom att nätet kan drivas närmare sina gränser. Elnät med sådana nya tekniker kallas ofta för ”Smarta Elnät". Implementering av sådana smarta elnät kan vara ett alternativ till traditionell nätplanering och åtgärder som utbyte av transformatorer eller konstruktion av nya kraftledningen.Nätets acceptansgräns är ett objektivt mått för att bestämma gränsen för nätets förmåga att integrera ny förbrukning eller produktion. Målet är att skapa större transparens och bidra till ett bättre faktaunderlag i diskussioner mellan nätoperatörer och ägare av distribuerade energiresurser. Denna avhandling utökar acceptansgränsmetoden för tillämpning med energilager och produktions nedstyrning och utvecklar ytterligare begrepp så som acceptansgränsen koefficienten.Forskningen visar hur varierbarheten hos olika förnyelsebara energikällor samverkar med förbrukningen och påverkar nätets acceptansgräns. Flera fallstudier från verkliga elnät och med uppmätt produktion och konsumtion presenteras. Fokus är på hur den tillåtna mängden förnyelsebara energikällor kan ökas med hjälp av energilagring, kontrollerad produktionsnedstyrning och med avancerad distribuerade skydd och kontroll applikationer. / Nicholas Etherden works at STRI AB (www.stri.se) in Gothenburg, Sweden. When he is not pursuing his half-time PhD studies he works as a specialist consultant in the field of Power Utility Automation, specialising on the IEC 61850 standard for power utility automation (today widely used in substations as well as some wind parks, hydro plants and DER and Smart Grid applications such as vehicle-to-grid integration). The author of this thesis received his Master of Science in Engineering Physics from Uppsala University 2000. Side tracks during his engineering studies included studies in theoretical philosophy, chemistry, ecology and environmental sciences as well as chairing the Swedish student committee of the Pugwash Conferences on Science and Worlds Affairs and later board member of the International Network of Engineers and of Scientists for Global Responsibility (INES) and chair of Swedish Scientists and Engineers Against Nuclear Arms. He has been a trainee at ABB in Västerås Sweden and spent six years as developer and team leader for the application development of a new relay protection family (ABB IED 670 series). In parallel to his professional work he studied power system engineering at Mälardalens University and travelled to all continents of the world. Since 2008 he is responsible for the STRI IEC 61850 Independent Interoperability Laboratory and a member of IEC Technical Committee 57 working group 10 "Power system communication and associated data models” and UCA/IEC 61850 User group testing subcommittee. He is co-author of IEC 61850-1 and main contributor to “Technical Report on Functional Test of IEC 61850 systems” and has held over 25 hands-on courses around the world on IEC 61850 “Communication networks and systems for power utility automation”. / SmartGrid Energilager

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