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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.
81

Can batteries be useful in industrialelectricity systems?

Abo Warda, Jamal January 2022 (has links)
This study provides an analysis of the benefits of adding solar PV and batteries to industries, both examing the grid-connected and off-grid cases.The electricity demand of 28 companies in Falkenberg, Sweden, whose industries require high voltages for electricity, were studied. We examined the extent to which these companies can depend on energy generated from photovoltaic cells and stored in batteries, as well as the impact of peak loads and the possibility of eliminating peaks when operating off-grid.The data for each of these cases were analyzed for companies to determine the energy that can be generated from photovoltaic cells on-site, and then take advantage of this energy directly and store the surplus in batteries to reduce dependence on the grid or reduce this dependence to a minimum, and study the role of the battery. We obtained interesting results and reliable systems during this study, as we noticed the effect of changing working hours in these companies in proportion to the times of energy production during the period of daily solar radiation.By studying the main load models in these companies and using the results and data analysis, it was noted that batteries can be a reliable solution, in which the energy generated from solar cells is used directly and the excess electricity is stored in the batteries later, and we noted the possibility of operating the entire system off-grid, which was found realistic if the company would have been located in Egypt. .
82

Off-grid Online : A Mixed-Strategy Survey Study of the Facebook Community ‘Living Off-Grid in Spain’

Glad, Marie January 2022 (has links)
The aim of this study is to explore and understand the motivations for belonging to the Facebook community ‘Living Off-Grid in Spain’ and how collaborative media is used for facilitating off-grid living and societal change. Two main theoretical frameworks are used for analyzing the empirical material of this study. The Uses & Gratifications (U&G) theory is applied to identify the uses and motivations for belonging to the community. And the concept of Community of Practice (CoP) is applied for understanding in what ways the community members use collaborative media to support each other in the practice of planning and executing sustainable off-grid living. The methodological approach contains a voluntary sampling of the population and a mixed-strategy survey for collecting both quantitative and qualitative data about the members and their engagement in the community. The study shows that a new U&G typology is needed for defining the motivations for participating in online communities where collaborative learning is a centerpiece. Additional uses such as Learning, Problem-solving, Inspiration, and Mentoring are proposed for further media studies in this field. And the characteristics of CoP serve to identify the importance that shared practices and mutual engagement have for the success of continuous knowledge exchange in online communities, a field that also would gain value from further media studies.
83

Osvětlovací systémy v ostrovních aplikacích / Lighting systems in off-grid applications

Lengyel, Ladislav January 2015 (has links)
Aim of the master's thesis is at first to explain appropriate light sources and lighting systems; secondly present suitable light sources selection for lighting a small space and design of an off-grid system. The last part consists of an overview about alternative energy transformations to light energy. The first of these three major themes focuses on the analysis of light sources suitable for use in applications with accumulation together with data on energy efficiency and the utilization efficiency associated with them, concentrating on their consumption and possible energy saving lighting within small applications. It ends with a description and calculations of electricity energy indicators for different types of rooms. The second and main part of the thesis is focusing on suitable light sources selection for off-grid systems and impacts on humans and the environment associated with it. An object representing a small application has been created in RELUX® software with suitable light sources installed in it. For this scene, appropriate parts of off-grid systems were selected, which could be used to power the proposed lighting. The last theme consists of a brief about alternative sources, most of which are still in development or existing only at a theoretical level. All of these alternative sources are having a possible application in the future.
84

Využití a obnova průmyslových objektů u Baťova kanálu / Design and operation of the coworking space

Koňariková, Lenka January 2022 (has links)
The diploma thesis solves the new utilization and renovation of an industrial building near the Baťa canal in the village of Huštěnovice which was used as former pumping station for agricultural purposes. The aim was to find such uses that will support the development of the adjacent area and at the same time will also refer to the original usage of the building. New community centre „PŘÍLIV“ with aquaponics connects both of them and what is more, it offers modern connection of people with nature. The construction plan is solved as a complex project form architectural study, through the project for the building permit to the design of the aquaponics technology itself. Project of the community centre and aquaponics is designed as off-grid building with minimal environmental impact.
85

Smart and Sustainable Off-grid Housing Powered by Vehicle to Anything (V2X) : An exploratory study to understand the innovation readiness and feasibility for off-grid living powered by Vehicle to Anything (V2X) / Smarta och hållbara off-grid boenden försörjda av en elbil med V2X

Borgefeldt, Hanna, Svensson, Emma January 2022 (has links)
For the EU to reach net-zero by 2050, an increased rate of renewable energy generation is needed. Off-grid tiny houses serve as a sustainable housing option as they are energy conservative, and their primary source of energy is renewable energy. However, off-grid living is faced with challenges due to the seasonal energy imbalance caused by the intermittent characteristics of renewable energy. This thesis aims to explore the potential of reducing this energy imbalance by using an electric vehicle (EV) to charge the home when there is an energy shortage and charge the EV when there is an energy surplus. This concept is enabled by bidirectional charging, also referred to as “Vehicle to Anything” (V2X). The main research question is to understand if an off-grid tiny house supported by V2X can be self-sufficient on energy and what the prerequisites for usage are. The method for answering this research question is firstly by conducting a general study followed by a case study. In the general study, industry experts are interviewed and surveyed to assess the innovation’s technology, market, and regulatory readiness and attributes of the innovation related to potential adoption. Thereafter, a case study with a partner in Sweden offering stays in off-grid tiny houses was conducted. The aim was to understand the system dynamics of the energy balance for an off-grid tiny house with solar panels and a home battery when adding an EV.  Results show that it is regulatory unproblematic to connect an EV to power off-grid living today, and the technology is more ready than the market. To increase the readiness level of the innovation, standardization of equipment and communication is needed. The attributes of the innovation that supports adoption are that the EV is mobile and offers large storing capacity which increases flexibility and hence decreases dependency on renewable energy. However, setting up the off-grid system and following safety regulations can be considered complex. Thereto, the innovation is seen as most applicable for short-term stays and individual usage. Results from the case study show that the EV can theoretically prolong the season for off-grid tiny house living by 1-4 months by reducing the energy imbalance and increasing self-sufficiency. Moreover, the EV can increase the share of renewable energy that is being used by storing energy when there is excess solar energy available.  On a final note, to answer the main research question if off-grid living supported by V2X can become self-sufficient on energy and what the prerequisites are for usage, the study concludes that it is theoretically possible, but the innovation is dependent on all technology components being tested and validated together in an off-grid environment. The EV needs to have bidirectional capabilities and the home needs to be equipped with smart software and an inverter to control the charging and discharging. Thereto, there needs to be a business model that creates value confirmed by the market, both customers and industry actors. Lastly, from a regulatory point of view, the concept is feasible as long as the installation of the energy system follows Swedish safety regulations. The EV can then, according to the model, theoretically help to prolong the season by reducing the energy balance making the energy system self-sufficient on energy. The EV can be discharged as well as charged by the excess solar, and hence the smart bidirectional charging of the EV and the home can increase theshare of renewable energy available for use and reduce the energy imbalance. Implications of this thesis suggest increased access to off-grid living as the V2X technology can prolong the season for people living off-grid as well as for off-grid businesses in the hospitality industry. This would allow for increased business value and opportunities within both the housing and tourism industry. The findings also support sustainable development as the innovation increases resource efficiency of the EV as it can serve multiple purposes, including transportation, energy storage, and energy supply. / För att EU ska nå nettonoll till 2050 krävs mer förnybar energi. Off-grid tiny houses är små hus som är frikopplade från stamnätet och är ett hållbart boendealternativ då de är energisnåla och deras primära energikälla är förnybar energi. I dagsläget finns det dock flera utmaningar med att bo off-grid till följd av den säsongsbaserade energiobalansen orsakad av de intermittenta egenskaperna hos förnybar energi. Därför syftar det här examensarbetet till att utforska potentialen för att minska energiobalansen genom att använda en elbil för att ladda hemmet när det råder energibrist och ladda elbilen när det finns ett energiöverskott. Detta koncept möjliggörs av dubbelriktad laddning, även kallad "Vehicle to Anything" (V2X). Den huvudsakliga forskningsfrågan är att undersöka om off-grid tiny house med stöd av V2X kan bli självförsörjande på energi och vilka förutsättningarna är för användning. Metoden för att besvara forskningsfrågan är inledningsvis en empirisk studie följt av en fallstudie. I den empiriska studien uppskattas den teknologiska, marknadsmässiga och regulatoriska mognadsgraden av att använda en elbil för att försörja off-grid boenden. Vidare undersöks innovationens egenskaper för att förstå hur lösningen skulle kunna tilltala möjliga användare. Studien gjordes genom att intervjua samt skicka ut en enkät till branschexperter. Därefter genomfördes en fallstudie med en partner i Sverige som erbjuder vistelser i off-grid tiny houses. Under fallstudien modellerades energisystemet bestående av ett off-grid hus, ett hembatteri samt solpaneler för att förstå hur energibalansen förändras när en elbil adderas till systemet. Resultaten visar att det är regulatoriskt oproblematiskt att ansluta en elbil till ett off-grid tiny house för att förse det med ström, och tekniken är mer redo än marknaden. För att innovationens mognadsgrad ska öka krävs mer standardisering av både utrustning och kommunikationsprotokoll. Egenskaper som uppmuntrar användning av innovationen är att elbilen är mobil och erbjuder stor lagringsmöjlighet vilket i sin tur minskar beroendet av förnybar energi. Det kan dock anses kompliceratatt sätta upp off-grid-systemet och följa de säkerhetsföreskrifter som krävs. Vidare ses innovationen som mest användbar för korttidsvistelser och individuellt bruk. Resultaten från fallstudien visar att elbilen kan förlänga säsongen för off-grid tiny houses boende med 1-4 månader genom att minska energiobalansen och öka systemets grad av självförsörjande. Dessutom kan elbilen öka andelen förnybar energi som används genom att lagra energi när det finns överskott av solenergi tillgänglig. Slutligen, för att svara på den huvudsakliga frågeställningen om off-grid tiny houses med stöd av V2X kan bli självförsörjande på energi och vilka förutsättningarna är för användning, drar studien slutsatsen att det är teoretiskt möjligt, men innovationen är beroende av att alla tekniska komponenter testas och valideras tillsammans i en off-grid miljö. Elbilen måste ha dubbelriktad laddning och hemmet måste utrustas med smart mjukvara och en växelriktare för att styra laddning och urladdning. Därför behöver det finnas en affärsmodell som skapar värde som bekräftas av marknaden, både av kunder och branschaktörer. Slutligen, ur ett regulatoriskt perspektiv, är konceptet genomförbart så länge installationen av energisystemet följer svenska säkerhetsföreskrifter. Elbilen kan då, enligt modellen, teoretiskt bidra till att förlänga säsongen genom att minska energibalansen och göra energisystemet självförsörjande på energi. Elbilen kan både ladda ur energi till boendet samt laddas av överskottet av solenergi, och därför kan den smarta dubbelriktade laddningen av elbilen och hemmet öka andelen förnybar energi tillgänglig för användning och minska energiobalansen. Implikationerna av denna uppsats tyder på ökad tillgång till off-grid boende eftersom V2X-tekniken kan förlänga säsongen för människor som bor off-grid såväl som för off-grid-företag inom besöksnäringen. Detta skulle möjliggöra ökat affärsvärde och möjligheter inom både bostads- och turistnäringen. Resultaten stöder också hållbar utveckling eftersom innovationen ökar resurseffektiviteten för elbilen eftersom den kan tjäna flera syften, inklusive transport, energilagring och energiförsörjning.
86

A techno-economic appraisal of renewable energy in remote, off grid locations in Nigeria : Obudu ranch as a case study / L. Olawalemi Ogunleye

Ogunleye, Lawrence Olawale January 2008 (has links)
Energy is central to economic development. It has been established that there is a clear correlation between energy consumption and living standards. Nigeria is a country of very industrious and enterprising people. However, due to non availability of adequate energy in the country, especially in the remote, off grid locations, the entrepreneurial inclination of the average Nigerian living in these locations has been largely stunted. Over the years, successive governments in the country, in realisation of the pivotal role of energy in national development, have explored various options to improve energy supply and availability, but the situation has not experienced any remarkable improvement. This has forced many businesses and households to resort to self provision through generators, often at exorbitant costs. This research work addresses the challenge of energy in remote, off grid locations by appraising the techno economic potential of renewable energy, using Obudu Ranch as a case study. This ranch is the foremost tourism resort in Nigeria, and has played host to a number of international events over the years. Presently, electricity is being generated through the use of diesel powered generating sets. The adjoining communities are currently without electricity, although a few of the residents have acquired generators for self provision, mostly for their domestic use. Aside the high cost associated with this, the discharge of noxious contaminants into the atmosphere is undesirable. The research entailed a working collaboration with some notable Non Governmental Organisations (NGOs) that have done extensive ground work in the area for access to some secondary data, as well as a number of corporate and governmental agencies that are relevant to the study. Further, the ranch was visited to establish hands-on, the existing renewable energy sources. A trade-off of these sources was carried out with reference to a number of relevant evaluation parameters to identify the most suited option for addressing the energy challenge. A comparative analysis of this selected source was then made to establish its techno economic potential against the existing source of power generation- diesel powered generating sets, which currently costs R1.5 million annually in running expenses. The findings from this research have established that a Renewable Energy source (mini hydro) is a more cost effective option than the diesel powered gen set, providing a 43% reduction in cost of energy generation, and a 42% reduction in the life cycle cost over the five year of analysis, compared to the status quo. In addition, it is also more environmentally friendly. Conclusively, the findings and recommendations of this research effort, if well implemented, will be beneficial to the ranch, the adjoining communities and other relevant stakeholders. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
87

A techno-economic appraisal of renewable energy in remote, off grid locations in Nigeria : Obudu ranch as a case study / L. Olawalemi Ogunleye

Ogunleye, Lawrence Olawale January 2008 (has links)
Energy is central to economic development. It has been established that there is a clear correlation between energy consumption and living standards. Nigeria is a country of very industrious and enterprising people. However, due to non availability of adequate energy in the country, especially in the remote, off grid locations, the entrepreneurial inclination of the average Nigerian living in these locations has been largely stunted. Over the years, successive governments in the country, in realisation of the pivotal role of energy in national development, have explored various options to improve energy supply and availability, but the situation has not experienced any remarkable improvement. This has forced many businesses and households to resort to self provision through generators, often at exorbitant costs. This research work addresses the challenge of energy in remote, off grid locations by appraising the techno economic potential of renewable energy, using Obudu Ranch as a case study. This ranch is the foremost tourism resort in Nigeria, and has played host to a number of international events over the years. Presently, electricity is being generated through the use of diesel powered generating sets. The adjoining communities are currently without electricity, although a few of the residents have acquired generators for self provision, mostly for their domestic use. Aside the high cost associated with this, the discharge of noxious contaminants into the atmosphere is undesirable. The research entailed a working collaboration with some notable Non Governmental Organisations (NGOs) that have done extensive ground work in the area for access to some secondary data, as well as a number of corporate and governmental agencies that are relevant to the study. Further, the ranch was visited to establish hands-on, the existing renewable energy sources. A trade-off of these sources was carried out with reference to a number of relevant evaluation parameters to identify the most suited option for addressing the energy challenge. A comparative analysis of this selected source was then made to establish its techno economic potential against the existing source of power generation- diesel powered generating sets, which currently costs R1.5 million annually in running expenses. The findings from this research have established that a Renewable Energy source (mini hydro) is a more cost effective option than the diesel powered gen set, providing a 43% reduction in cost of energy generation, and a 42% reduction in the life cycle cost over the five year of analysis, compared to the status quo. In addition, it is also more environmentally friendly. Conclusively, the findings and recommendations of this research effort, if well implemented, will be beneficial to the ranch, the adjoining communities and other relevant stakeholders. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
88

Sistema de geração distribuída fotovoltaica com acumulação, controle da injeção de potências ativa e reativa, com capacidade de operação conectada e ilhada /

Alves, Marcos Gutierrez. January 2017 (has links)
Orientador: Carlos Alberto Canesin / Resumo: Frente aos novos desafios impostos ao cenário energético mundial, esta tese de doutorado implementa e analisa uma micro-rede de geração distribuída (GD), com acumulação e capacidade de operação conectada ou desconectada da rede de distribuição de energia elétrica (RDEE). A energia é fornecida à RDEE através de seis inversores monofásicos, constituindo uma rede trifásica, sendo três deles com capacidade de operação ilhada e conectada, e outros três com características de fonte de corrente que podem injetar energia de forma controlada, ativa ou reativa, no ponto de conexão comum (PCC). Através do sistema de acumulação com baterias do tipo chumbo-ácido, também é possível que o sistema minimize o consumo de energia da RDEE, mesmo quando não há energia solar, extraindo potência das baterias. Tendo em vista que a quase totalidade dos inversores utilizados em um sistema de GD fornecem somente potência ativa, ou trabalhem com fator de potência fixo, este trabalho também implementa o controle dinâmico de P e Q na micro-rede, atuando como compensador de tensão no PCC e promovendo melhorias na qualidade da energia elétrica. A micro-rede é gerenciada por um programa desenvolvido para o controle de todos os dispositivos essenciais presentes na GD, incluindo controle da carga e descarga do sistema de acumulação, controle dos contatores de conexão de todo o sistema, e controle do firmware dos inversores conectados, permitindo total liberdade de gestão da energia disponível, resultando numa ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Considering the new challenges imposed in the energetic scenario around the world, this PhD thesis implements and analyzes a micro-grid of Distributed Generation (DG) plant with accumulation and capability of operation connected or islanded from the electric power distribution grid. The system will supply power to the utility grid and local loads through six single-phase inverters, constituting a three-phase system, among which three are with capability to operate in islanded and connected mode, and the other three single-phase inverters with current source characteristic that can inject active or reactive power in a controlled manner at the point of common coupling (PCC). Through the accumulation system with lead-acid batteries technology, it is also possible that the system minimizes the utility grid consumption, though without solar energy. Given that most of the available inverters for DG are designed only to provide active power or to operate with a fixed power factor, this work, in the meantime, implements the dynamic control of the supplied active and reactive power (P and Q) in micro-grid, acting as a voltage compensator at the PCC to improve the quality of electric power. The micro-grid is managed by software designed to control and communicate with all essential devices in DG, including control of charge and discharge of the accumulation system, control of the whole system connection contactors, and the firmware control of grid connected inverters, which allow a wid... (Complete abstract click electronic access below) / Doutor
89

Sistema de geração distribuída fotovoltaica com acumulação, controle da injeção de potências ativa e reativa, com capacidade de operação conectada e ilhada / Photovoltaic DG with accumulation, active and reactive power control for grid-connected and intentional islanding operations

Alves, Marcos Gutierrez [UNESP] 21 August 2017 (has links)
Submitted by MARCOS GUTIERREZ ALVES null (mmarkos.alves@gmail.com) on 2017-10-18T17:25:15Z No. of bitstreams: 1 Marcos Gutierrez Alves - Tese.pdf: 10359243 bytes, checksum: 24da24ccb395d0581201cc49607f4bf6 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-10-23T18:18:25Z (GMT) No. of bitstreams: 1 alves_mg_dr_ilha.pdf: 10359243 bytes, checksum: 24da24ccb395d0581201cc49607f4bf6 (MD5) / Made available in DSpace on 2017-10-23T18:18:25Z (GMT). No. of bitstreams: 1 alves_mg_dr_ilha.pdf: 10359243 bytes, checksum: 24da24ccb395d0581201cc49607f4bf6 (MD5) Previous issue date: 2017-08-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Frente aos novos desafios impostos ao cenário energético mundial, esta tese de doutorado implementa e analisa uma micro-rede de geração distribuída (GD), com acumulação e capacidade de operação conectada ou desconectada da rede de distribuição de energia elétrica (RDEE). A energia é fornecida à RDEE através de seis inversores monofásicos, constituindo uma rede trifásica, sendo três deles com capacidade de operação ilhada e conectada, e outros três com características de fonte de corrente que podem injetar energia de forma controlada, ativa ou reativa, no ponto de conexão comum (PCC). Através do sistema de acumulação com baterias do tipo chumbo-ácido, também é possível que o sistema minimize o consumo de energia da RDEE, mesmo quando não há energia solar, extraindo potência das baterias. Tendo em vista que a quase totalidade dos inversores utilizados em um sistema de GD fornecem somente potência ativa, ou trabalhem com fator de potência fixo, este trabalho também implementa o controle dinâmico de P e Q na micro-rede, atuando como compensador de tensão no PCC e promovendo melhorias na qualidade da energia elétrica. A micro-rede é gerenciada por um programa desenvolvido para o controle de todos os dispositivos essenciais presentes na GD, incluindo controle da carga e descarga do sistema de acumulação, controle dos contatores de conexão de todo o sistema, e controle do firmware dos inversores conectados, permitindo total liberdade de gestão da energia disponível, resultando numa importante ferramenta acadêmica de aprendizagem. Adicionalmente, a planta de GD é monitorada por meio de um programa de aquisição de dados do fluxo de energia elétrica que flui entre a GD e a RDEE, armazenando os dados relevantes em um banco de dados de informações para análises em longo prazo. É apresentada uma revisão bibliográfica para o cenário energético mundial e no Brasil, além das configurações de micro-rede com GD mais utilizadas no setor atualmente. O diagrama geral da micro-rede com GD é exposto, com descrição de cada equipamento e dimensionamento das fontes de energia solar. Finalmente, resultados experimentais e estruturas dos códigos são apresentados e discutidos. / Considering the new challenges imposed in the energetic scenario around the world, this PhD thesis implements and analyzes a micro-grid of Distributed Generation (DG) plant with accumulation and capability of operation connected or islanded from the electric power distribution grid. The system will supply power to the utility grid and local loads through six single-phase inverters, constituting a three-phase system, among which three are with capability to operate in islanded and connected mode, and the other three single-phase inverters with current source characteristic that can inject active or reactive power in a controlled manner at the point of common coupling (PCC). Through the accumulation system with lead-acid batteries technology, it is also possible that the system minimizes the utility grid consumption, though without solar energy. Given that most of the available inverters for DG are designed only to provide active power or to operate with a fixed power factor, this work, in the meantime, implements the dynamic control of the supplied active and reactive power (P and Q) in micro-grid, acting as a voltage compensator at the PCC to improve the quality of electric power. The micro-grid is managed by software designed to control and communicate with all essential devices in DG, including control of charge and discharge of the accumulation system, control of the whole system connection contactors, and the firmware control of grid connected inverters, which allow a wide control over the available energy and provide a significant academic studying platform. In addition, the energy flow between the DG and the utility grid is monitored through a power quality monitoring device, which is capable to send daily reports by email. In this way, a program was developed to store and recover all the relevant data in a database for the long-term analysis, compiling the results for easy interpretation. A literature review is presented for the world energy scenario, with more focus in Brazil, besides the micro-grid configurations with DG most used in the sector currently. This work also shows the general diagram of the micro-grid with DG describing the equipment and dimensioning the solar energy sources. Finally, it demonstrates and discusses experimental results and code structures.
90

Ostrovní systémy / Autonomous energy systems

Dolinský, Filip January 2018 (has links)
Master thesis deals with usage issues of autonomous, self-sufficient and decentralized systems. In the first part convectional and experimental sources for autonomous systems are disclosed. Second chapter deals with accumulation of electrical and thermal energy and possibilities of applications. 3rd part is focused on pilot project realized for autonomous and smart systems, which were built in last years. In the 4th chapter electrical and thermal energy consumption curves are made on daily and monthly basis for 4 type objects. In the fifth part issue of autonomy is explained, and for type buildings solutions are made with additional return on investment. The last chapter is focused on calculation of thermal accumulator and briefly discloses small district heating.

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