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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.
791

Vindkraft som ett socialekologiskt fix : Två fallstudier om vindkraft i Norrbotten och Östergötland / Wind power as a socio-ecological fix : Two case studies regarding wind power in Norrbotten and Östergötland

Berber, Aylin, Wernersson, Louise January 2021 (has links)
För att studera hur omställningen från vertikal till horisontell energiutvinning kommer att påverka samhället har två fallstudier gjorts. Fallstudierna tillsammans med teorin om socialekologiska fix har använts för att analysera de socialekologiska transformationerna som sker på landskap och politiken som finns kring dessa transformationer. En fallstudie har studerat vindkrafts projektet Markbygden i Norrbottens län och den andra studerar vindkraftsetableringen i Östergötlands län. Dessa fallstudier har genomförts genom en kvalitativ studie i form av intervjuer med aktörer som är med och påverkar samt påverkas av dessa vindkraftsetableringar. Fallstudierna visar att landskapet har förändrats fysiskt av byggnationen av vindkraftverken vilket har bidragit till en transformation av markanvändningen. Karteringar som har gjorts i samband med vindkraftsetablering har påverkat hur människor använder och förhåller sig till marken samt hur ägandeförhållandena ser ut. Vidare har vindkraftsetableringen i Östergötland och Norrbotten lett till olika konflikter som exempelvis störningar av ljus och buller samt konflikter med renskötseln som tidigare bedrivits i området Markbygden. Dessa konflikter har alltså uppkommit till följd av den landskapstransformation som har skett i samband med vindkraftsutbyggnaden. I Norrbotten och Östergötland är en ekonomisk kompensation respektive en markhyra aktuell, dock anses dessa vara otillräckliga för att kompensera för den förlust av betesmark för renar som sker i Norrbotten respektive för de besvär lokalbefolkningen upplever med bullret i Östergötland. Slutligen visar resultatet även på att den största drivkraften för företag att etablera vindkraft är vinst och därmed sker otillräckliga karteringar av vind och markanvändning vilket försvårar implementeringen av vindkraft. Slutsatserna för denna rapport är därmed att olika kartläggningar av främst vind har förändrat markanvändningen och andra verksamheter som tidigare bedrivits i landskapet har begränsats och i stor utsträckning ersatts av produktion av vindkraft. Då vindkraften i Östergötland och Norrbotten har byggts ut med otillräckliga kartläggningar som inte tar de sociala relationerna i beaktning har dessa olika konflikter uppstått. / To study how the transition from vertical to horizontal energy recovery will affect society, two case studies have been conducted. The case studies, together with the theory of socio-ecological fixes, have been used to analyze the socio-ecological transformations that take place on landscapes and the politics that exist around these transformations. The first case study concerned the wind power project called Markbygden in Norrbotten County and the second case study concerned wind power establishment in Östergötland County. These case studies were conducted through a qualitative study in the form of interviews with actors who are involved in and are affected by these wind power establishments. The case studies show that the landscape has changed physically by the construction of wind turbines, which has contributed to a transformation of land use. Mappings that have been made in correlation with wind power establishment have affected how people use and relate to the land and what the ownership conditions look like. Furthermore, the establishment of wind power in Östergötland and Norrbotten has led to various conflicts such as disturbances caused by light and noise as well as conflicts with reindeer husbandry that was previously conducted in the Markbygden area. These conflicts have thus arisen as a result of the landscape transformation that has taken place in connection with the expansion of wind power. In Norrbotten and Östergötland, financial compensation and land rent are current, however, these are considered insufficient to compensate for the loss of grazing land for reindeer that occurs in Norrbotten and for the problems the local population experiences with the noise in Östergötland. Finally, the results also show that the biggest driving force for companies to establish wind power is profit and thus insufficient mapping of wind and land use takes place, which makes it more difficult to implement wind power. The conclusions of this report are thus that various mappings of mainly wind have changed land use and other activities previously conducted in the landscape have been limited and to a great extent been replaced by the production of wind power. As wind power in Östergötland and Norrbotten has expanded with insufficient mappings that disregard existing social relations, the various conflicts have arisen.
792

The complex necessity : A qualitative study exploring the current process for grid connection of large-scale onshore wind farms in Sweden

Kuhlefelt, Anna January 2020 (has links)
Sweden has a goal of having an electricity production solemnly comprising renewable energy sources by the year 2040. To cater for the fulfillment of this goal, more onshore wind power will be needed in Sweden. The wind farm itself has been studied both in terms of its impacts on societal and environmental interests as well as how the Swedish spatial planning system paves the way for more wind power or not. The connection of wind farms to the regional and national transmission grid is far less studied. Therefore, this thesis explores the grid connection process and how it is experienced by the practitioners in terms of wind power developers and network operators. Also, the ways in which the power grid is taken into account when finding a location for a wind farm is studied. This is done by a literature review and a thematic analysis of ten conducted interviews. The grid connection process is presented, along with the four main themes identified by the thematic analysis; Making two long processes parallel, The importance of grid capacity, Dialogue between the developer and the network operator and Proactive consideration of grid connection. The results suggest that the grid connection process, in combination with the wind farm development, is experienced as time-consuming, which gives rise to problems regarding technology development and puts the finalization of the entire project at risk. Consequently, the practitioners want to make the processes more parallel. This is however complicated by the associated risks of not being reassured grid capacity and inflexible permit procedures. Another important result is that the network operators and developers often have different interests to guard, which can complicate the grid connection process further. The available capacity in the grid is crucial when locating a wind farm, but also the economic distance to the point of connection, which in turn depends on several parameters. It is suggested that consideration of the power grid should be more integrated with the spatial planning in Sweden. This can improve the predictability of wind power planning, promote adequate power grid planning and facilitate the Swedish goal of an electricity production only comprised of renewable energy by 2040. / För att genomföra en grön omställning av Europas energisystem väntas mer elproduktion av förnyelsebar energi integreras. Sverige har som mål att ha en elproduktion som enbart består av förnyelsebar energi till år 2040. För att åstadkomma detta mål förväntas andelen vindkraft i landet att öka. Att ansluta till elnätet hör till en av de fundamentala nödvändigheterna för att etablera en vindkraftpark. Trots detta så är planering och utförande av nätanslutning till det svenska elnätet en förbisedd del av processen för att etablera vindkraft i Sverige. Syftet med denna studie är därför att undersöka anslutningsprocessen för landbaserad och storskalig vindkraft och bidra att till ökad kunskap kring hur denna process upplevs av utövarna. Dessutom undersöks det hur vindkraftsprojektörer tar hänsyn till elnätet när de letar områden för vindkraft. Detta görs med en litteraturstudie angående hur anslutningsprocessen går till, följt av en tematisk analys av intervjuer med nätägare och vindkraftsprojektörer. En övergripande bild av anslutningsprocessen och relaterad litteratur presenteras. Fyra huvudteman identifieras från den tematiska analysen; Att göra två långa processer parallella, Signifikansen av nätkapacitet, Dialogen mellan vindkraftsprojektör och nätägare och Proaktiv hänsyn av nätanslutning. Resultaten visar att en stor utmaning med anslutningsprocessen är att den tillsammans med utvecklingen av vindparken upplevs som så pass långdragen i tid, att problem uppstår med teknikutveckling och genomförandet av projektet i sig. Detta bidrar till att vindkraftsprojektörer och nätägare vill försöka göra processerna för utveckling av vindparken och nätanslutningen mer parallella. Att processen för att utveckla vindparken är tidskrävande och osäker bidrar till att den nödvändiga nätkapaciteten inte alltid kan garanteras, vilket försvårar en synkronisering av processerna. Ett ytterligare viktigt resultat är att nätägare och vindkraftsprojektörer ofta har olika intressen under nätanslutningsprocessen, vilket kan komplicera dess förlopp. Var det finns nätkapacitet är en stor faktor vid lokalisering av vindkraft, men även det ekonomiska avståndet till en anslutningspunkt som i sin tur beror på flera parametrar. Elnätsfrågan är komplex både när det gäller lokalisering och anslutning av vindkraft. Men för att skapa goda förutsättningar för mer vindkraft i Sverige, och för uppfyllandet av målet till 2040, bör elnätsfrågan hanteras proaktivt och integreras mer i den fysiska planeringen i Sverige.
793

Counter Rotating Axis Floating Tilting Wind Turbine : Cost and Efficiency analysis of the Secondary electric machine

Nordin, Emelie, Carredano Robertsson, Alicia January 2024 (has links)
Floating offshore wind turbines show great potential within the energy industry, especially for deeper waters where traditional fixed-bottom turbines cannot be used. Offshore locations also offer stronger and more stable winds compared to onshore locations. The study explores the impact of the secondary machine efficiency on the electricity production in a Counter Rotating Axis Floating Tilting (CRAFT) wind turbine. The counter-rotating design holds promise for achieving high overall system efficiency.  MATLAB simulations show that it is possible to maintain a lower secondary machine efficiency without compromising stability. Reviewing two control systems confirms that using a robust control algorithm with optimized TSR ensures system stability in both high and low winds. A decrease in secondary electric machine efficiency from 97% to 93% resulted in a 0.03% reduction in annually generated electricity, whereas a similar decrease in primary electric generator efficiency led to a 1% reduction instead. Decreasing the secondary machine efficiency further to 83% resulted in a 0.1% reduction in annual generated electricity. Thus, the secondary machine's efficiency is shown to be less critical for the electricity production than the primary generator’s efficiency.  Choosing an asynchronous over a synchronous option as the secondary machine is economically advantageous since its lower efficiency of 83% instead of 97% does not significantly affect the electricity production. Moreover, the lower magnet cost for the asynchronous machines positively impacts economic metrics like LCoE, NPVI and payback period, making the asynchronous generator a more favourable economic choice. Further research areas to obtain higher accuracy include integrating differences in maintenance costs and conducting a more in-depth assessment of the investment costs associated with the two types of generators. Additionally, considering airflow losses around turbine blades and airflow interaction amongst the turbines could further enhance the model accuracy.
794

En fossilfri elframtid : En kvantitativ analys av samvariationen mellan sol-, vind- och vattenkraft för en fossilfri elproduktion i Sverige / A fossil free future

Berg, Moa, Blomqvist, Victor January 2024 (has links)
Syftet med studien var att undersöka samvariationen och korrelationen mellan de variabla förnybara energikällorna sol-, vind- och vattenkraft i fyra olika begränsade områden i Sverige. Studien ämnade att identifiera mönster mellan energislagen för att undersöka huruvida ett elkraftsystem enbart baserat på förnybara energikällor i Sverige är möjligt. Initialt genomfördes en litteraturstudie i syfte att ge kvalitativt underlag för det komplexa ämnet som undersöktes. Analysen och den kvantitativa delen av studien grundades på historiska klimatologiska data. Arbetet genomfördes i sin tur med hjälp av mjukvaran Matlab, där data hanterades och bearbetades. Parametrar och variabler som diskuterades och identifierades var framförallt effektspektrum, korskovarians och korrelation. Tidigare forskning tyder på att både positiv och negativ korrelation mellan olika variabla energislag förekommer beroende på vilka geografiska förutsättningar och vilket tidsspann som undersökts. Denna studie fann att negativ korrelation mellan sol- och vindkraft återkom för samtliga platser som studerades, medan sol- och vattenkraft istället korrelerade positivt. För vatten- och vindkraft var resultaten inte lika entydiga utan olika resultat erhölls beroende på tidsintervallet. / The purpose of the study was to examine the co-variation and correlation among the variable renewable energy sources solar, wind and hydropower in four different confined regions in Sweden. The study aimed to identify patterns among the energy sources to investigate whether a power system based on renewable energy sources in Sweden is achievable. Initially, a literature review was conducted to provide qualitative background for the complex subject investigated. The analysis and quantitative aspect of the report were based on historical climatological data. The work was carried out using Matlab software, where data was handled and processed. Parameters and variables discussed and identified primarily included power spectrum, cross-covariance, and correlation. Previous research suggests both positive and negative correlations among different variable energy sources occur depending on the geographic conditions and time span studied. This study found that negative correlation between solar and wind power recurred for all sites examined, while solar and hydropower instead showed a positive correlation. For hydropower and wind power, the results were not as consistent, with different outcomes depending on the time interval analyzed.
795

Kommunal Samverkan och Förnybar Energi : En studie om kommunal samverkan för utbyggnad av landbaserad vindkraft / Municipal Collaboration and Renewable Energy : A study on municipal collaboration for the expansion of onshore wind power

Kanhaleela, Iyara, Stålhammar, Emilia January 2024 (has links)
Energy production in southern Sweden is insufficient to meet the demand. As a result, Skåne relies on electricity imports from other parts of the country and abroad. Region Skåne sees potential in increasing energy production through renewable resources, including wind power. Many land-based wind turbines in Skåne are outdated and need upgrades in the near future. Wind turbines hold significant potential for future electricity production, necessitating further expansion to meet the growing demand for electricity. Wind power planning transcends municipal boundaries, requiring intermunicipal collaboration for effective wind power expansion. In 2010, three neighboring municipalities - Helsingborg, Höganäs, and Ängelholm - developed a thematic addition to identify suitable land for wind power expansion. This study aims to investigate the importance of municipal collaboration in wind power expansion and the challenges and opportunities municipal planning presents for renewable energy production. The methodology includes interview studies and document analysis to capture the broad aspects of collaboration and wind power development. The theoretical framework applies governance at various types and levels. The results highlight the significance of effective dialogue between municipalities for planning sustainable energy sources. Despite some debate over the thematic addition, the study underscores the need for cross-municipal cooperation to optimize planning. Municipal collaboration can address challenges in planning renewable energy production, but it requires political support and balancing diverse interests. Intermunicipal cooperation is crucial for tackling the challenges of renewable energy sources and for sharing resources and expertise among municipalities.
796

Farhågor inför etablering av vindkraft : Möjlig påverkan på hälsa och miljö / Concerns about the establishment of wind power : Potential impacts on health and the environment

Vesik, Hanne January 2024 (has links)
Enligt EU:s klimatlag ska regionen till år 2050 vara klimatneutral, och som en del i det arbetet har Sveriges riksdag upprättat ett nationellt mål om att Sverige år 2040 ska ha enbart förnybar elproduktion. Därför har Energimyndigheten i samarbete med Naturvårdsverket tagit fram en strategi för en hållbar utbyggnad av vindkraften. Större vindkraftsetableringar för med sig ingrepp i miljön som kan påverka såväl djur och natur som människor. I media och andra forum, såsom på hemsidor för olika organisationer mot vindkraft, pågår en debatt kring vindkraftens för- och nackdelar, och syftet med den här studien var att undersöka huruvida de farhågor rörande miljö och hälsa som uttrycks inför landbaserade vindkraftsetableringar stämmer överens med forskning och upplevelsen hos människor som lever med vindkraft i sin närhet.  Argument mot vindkraft identifierades genom sökning i dagspress, och information om vindkraftens konsekvenser samlades in genom en enkätundersökning med personer som bodde i närheten av vindkraft och med hjälp av vetenskapliga artiklar och rapporter från statliga myndigheter. Argumenten avgränsades till negativa effekter på människors hälsa med avseende på ljus, buller (inklusive infraljud) och utsläpp av mikroplaster och kemikalier; påverkan på naturen inklusive djurlivet, samt förändring av människors närmiljö. Respondenterna i enkätundersökningen var generellt sett positiva till vindkraft, och det som störde var främst ljudet, vilket för alla utom en endast upplevdes i begränsad omfattning. De vetenskapliga artiklar som studerades visade ett liknande resultat. De hälsorelaterade effekter som visades ha ett samband med vindkraft handlade om irritation och sömnstörningar på grund av ljudet. Sambandet konstaterades dock som komplext då andra faktorer såsom attityd också kunde ha en påverkan, vid sidan av ljudet som sådant. Vindkraften tycktes inte stå för några betydande utsläpp av mikroplaster, bisfenol-A eller PFAS, i jämförelse med andra källor. Kunskapsläget kring påverkan på natur och djurliv visades vara bristfälligt ur ett vetenskapligt perspektiv. Enkätstudien visade inte på någon omfattande påverkan av närmiljön, utan förändringar i landskapet upplevdes som något man vande sig vid. / According to the European Climate Law the region should be climate neutral by 2050, and as a part of that effort the Swedish parliament has set up a national goal that by the year 2040 Sweden should have only renewable electricity production. Therefore, the Swedish Energy Agency together with the Swedish Environmental Protection Agency has developed a strategy for a sustainable expansion of wind power. Larger installations of wind turbines entail interventions in the environment which can affect animals and nature as well as human beings. In media and other forums, like web sites for different organizations against wind power, there is an ongoing debate about the pros and cons of wind power, and the purpose of this study was to investigate if the concerns about the environment and health that comes up ahead of land-based wind power installations corresponds with science and the experience of people who live nearby wind turbines.  Argument against wind power wad identified through searching in daily newspaper, and information about the consequences of wind power was gathered through a survey with people living near wind turbines, and reports from government agencies. The arguments were limited to negative as well as through scientific articles effects on human health regarding to light, noise (including infrasound) and release of microplastics and chemicals; impact on nature including wildlife, and changes in people’s immediate environment. The respondents in the survey were generally positive towards wind power, and the main disturbance was the noise, which for all but one was experienced only to a limited extent. The scientific articles studied showed a similar result. The health-related effects associated with wind power were related to irritation and sleep disturbances due to the noise. However, the relationship was considered complex as other factors such as attitude also could have an impact beside the actual noise. Wind power did not seem to contribute to any significant emissions of microplastics, bisphenol-A or PFAS, compared to other sources. The state of knowledge regarding the impact on nature and wildlife was shown to be inadequate from a scientific perspective. The survey did not indicate any significant impact on the immediate environment, but changes in the landscape were perceived as something one got used to.
797

Techno-Economic Analysis of Wind Power-to-Hydrogen / Teknoekonomisk analys av vindkraft-till-vätgas

Muhsin, Zeinab January 2023 (has links)
I Sverige har målet länge varit att reducera mängden växthusgasutsläpp från transportsektorn [1]. Ambitionen har därför varit att försöka fasa ut användningen av fossila bränslen som till exempel diesel. Det har bland annat gjorts genom att öka andelen elbilar och skapa förutsättningar för det genom att etablera en storskalig infrastruktur för laddningsstationer runtom i landet. På senare tid har intresset för vätgas som ett potentiellt drivmedel för fordon ökat markant. Detta har i sin tur motiverat olika aktörer (industri, akademi, transportsektor och offentliga sektor) i Mellansverige att ingå i ett partnerskap för att tillsammans vidareutveckla detta mål genom att initiera samverkansprojektet ”Mid Sweden Hydrogen Valley”. Projektets ambition är att utforma och driva storskalig vätgasproduktion i syfte att bland annat stegvis introducera vätgasdrivna transportmedel i Gävle hamn som ett alternativ till nuvarande dieseldrivna fordon i hamnen. Detta då vätgasdrivna fordon erbjuder grön transport, längre körsträcka, snabbare påfyllningstid samt en viktmässigt lättare bränslelager jämfört med tunga batterier i elbilar. För att uppnå detta måste först vätgasinfrastruktur etableras för att skapa en tillgänglighet och därför har Mellansverige som huvudmål att ta en ledande roll.  Detta masterprojekt hade som mål att utforma och undersöka om en storskalig vätgasproduktionsanläggning som drevs på förnybar energi (vindkraft), hade potentialen att bli ekonomiskt lönsamt utifrån ett investeringskalkylsperspektiv. Detta gjordes genom att först konstruera en generell och optimerad konfiguration av en sådan anläggning. Detta tillvägagångssätt involverade bland annat att ta reda på vilka relevanta komponenter som behövdes, analysera lämpliga teknologier och undersöka komponenternas kommersiella tillgänglighet. En tekno-ekonomiskt analys tillämpades därefter på den färdigställda anläggningen. Den tekno-ekonomiska analysen genomfördes i form av en fallstudie för åren 2019, 2020 och 2021, där en fiktiv vätgasanläggning i Gävle hamn anslöts till en fiktiv havsbaserad vindkraftspark strax utanför hamnen. Denna havsbaserade vindkraft var i samma stund ansluten till nätet via en närliggande anslutningspunkt. Syftet var att ta reda på vid vilka spotpriser som funktion av vätgaspris, där det var lönsamt att producera vätgas i stället för att sälja elektriciteten direkt till elmarknaden. Dessa spotpriser räknades fram genom att subtrahera alternativintäkten av att sälja elen till nätet från vätgasens försäljningspris. Dessa spotpriser användes till att erhålla antalet lönsamma produktionstimmar av vätgas. Baserat på dessa lönsamma produktionstimmar kunde den totala generade inkomsten av vätgasförsäljning kalkyleras. Den slutliga vinsten beräknades genom avdrag av anläggningens fasta kostnader från den genererade rörliga inkomsten. Denna fallstudie är baserad på en djupgående litteraturstudie samt kontakt med Svenska Kraftnät (SvK), Energimyndigheten, diverse vindkraftsproducenter och Svea Vind Offshore. Tre varianter av fallstudien skapades där den enda skillnaden var storlekarna på huvudkomponenterna PEM elektrolys, kompressor, lager och vätgastankstation. I denna rapport valdes följande tre elektrolyskapaciteter: 5 MW, 10 MW och 20 MW.  Resterande komponenter dimensionerades utifrån elektrolysens kapacitet. Anledningen till att tre olika anläggningsvarianter studerades var för att ta reda på om det fanns ett tydligt samband mellan anläggningens storlek och sannolikheten att uppnå ekonomisk lönsamhet. Resultaten visade att dessa tre anläggningsstorlekar bar på olika för- och nackdelar. Fördelen som en 5 MW anläggning hade var till exempel flest antal produktionstimmar men nackdelen att den producerade minst mängd av vätgas. En 20 MW anläggning hade minst antal produktionstimmar men störst vätgasproduktion vilket resulterade i höga vinster. Enligt vad som kan förväntas låg 10 MW-anläggningen mellan 5 MW och 20 MW när det kom till antalet produktionstimmar och genererad vinst. Denna information var dock inte tillräcklig för att utfärda en slutlig bedömning gällande vilken anläggning som hade störst potential att uppnå lönsamhet. Detta grundade sig i att alla dessa anläggningsvarianter var enkelt konstruerade, vilket innebar att många mindre komponenter som också har en teknisk och ekonomisk inverkan, inte togs med i beräkningarna. Utöver detta så antogs även att anläggningen arbetade helt isolerat, vilket innebar att inget vätgasläckage ägde rum, något som inte överensstämmer i praktiken. / The goal to reduce emissions of greenhouse gases from the transportation sector in Sweden, has been ongoing for a while [1]. Therefore, the ambition to phase out the usage of fossil fuels such as diesel, has been actively taking place through different strategies. One such strategy is to increase the share of electric cars and apply a major effort in establishing a large-scaled infrastructure for charging stations throughout the country. Recently, interest in hydrogen as a potential fuel has significantly increased. This has in turn motivated different actors (industry, academia, transport, and public sector) in mid Sweden to form a partnership to further develop this goal by initiating a collaborative project called "Mid Sweden Hydrogen Valley”. The project’s ambition is to construct and operate a large-scale hydrogen production facility with the aim of, among other things, gradually introducing hydrogen fueled vehicles in Gävle harbor. The hydrogen fueled vehicles will pose as alternatives to current operating diesel fueled vehicles in the harbor. The plausible reasons for hydrogen fuel in the transport sector is that it offers green transport, longer driving distances, faster refueling time, and a lightweight fuel storage compared to the heavy batteries in electric cars. To achieve this, hydrogen infrastructure must first be established to create accessibility. Thus, the collaboration in mid Sweden has the mission of taking a leading role in this matter.  The aim of this master thesis is to investigate whether a large-scale hydrogen production facility powered by renewable energy (wind energy) has the potential of becoming economic viable from the perspective of an investment calculation. This investigation was executed by firstly constructing a generalized and optimized configuration of such a facility, which, in turn, was accomplished by analyzing what type of relevant equipment that was needed, studying, and selecting appropriate technologies, and examining the commercial availability of the equipment. Thereafter, a techno-economic analysis on the facility’s operational process was applied. This analysis was conducted in the form of a case study for the following target years 2019, 2020 and 2021, where a hydrogen production plant was placed in Gävle harbor and was connected to a hypothetical offshore wind farm, situated just outside the harbor. This offshore wind farm was simultaneously connected to the grid via a nearby connection point. The purpose was to determine which spot prices, as a function of different hydrogen prices, made it possible to produce and sell hydrogen at a profit rather than selling the electricity directly to the grid. These breakeven spot prices were computed by subtracting the alternative revenue of selling electricity to the grid from the selling price of hydrogen. Thereafter, these spot prices were used to obtain the profitable number of hydrogen production hours. Based on these hydrogen production hours, the total variable income generated from selling hydrogen could be calculated. Finally, the actual profit was calculated by deducting the facility's fixed costs from the generated income. This case study was based on an in-depth literature research and contact with Svenska Kraftnät (SvK), the Swedish Energy Agency, different wind power producers, and Svea Vind Offshore. Three variants of the case study were produced, where the only difference were the sizes of the main components: PEM electrolysis, compressor, storage, and hydrogen refueling station. In this report, the following three electrolyzer capacities 5 MW, 10 MW, and 20 MW, were selected. The dimensions of the other components were based on the electrolyzer’s capacity. The reason for producing three different facility sizes, was to determine whether there was a correlation between facility size and the probability of achieving economic profitability. The results showed that these three facilities possessed different advantages and drawbacks. The 5 MW facility had the advantage of obtaining the highest number of productions hours but had the drawback of generating the least volume of hydrogen. However, the 20 MW facility had the fewest production hours but the highest volume of hydrogen production, resulting in high profits. Lastly, the 10 MW facility fell between the 5 MW and 20 MW in terms of the number of production hours and generated profit. However, this information was not sufficient to make a final deciding of which facility size possessed the highest chance of achieving profitability. The reason for this is that the technical and economic impact of small components were disregarded in the calculations. Additionally, these facilities were also assumed to operate with perfect insulation, meaning no occurrence of hydrogen leakage took place, which is not realistic in practice.
798

Análise de estabilidade de sistemas de potência em presença de altos níveis de penetração de energia eólica / Analysis of power system stability in presence of high levels of wind power penetration

Cortes, David Joel Figueroa 27 June 2014 (has links)
Atualmente, a energia eólica é uma das fontes renováveis mais reconhecidas, e sua penetração em sistemas elétricos de potência está se incrementando consideravelmente. Por consequência, a participação de turbinas eólicas em sistemas elétricos de potência tem se incrementado e pode influenciar o comportamento geral do sistema de potência. Portanto, é importante estudar o desempenho de turbinas eólicas em sistemas elétricos e sua interação com outros equipamentos de geração e cargas. O principal objetivo nesta dissertação é determinar o desempenho dinâmico de diferentes tecnologias ligadas nos sistemas elétricos considerando diferentes níveis de penetração e diferentes perturbações elétricas mediante simulações realizadas usando um toolbox de Matlab/Simulink, SimPowerSystems. As tecnologias avaliadas são (a) o gerador de indução duplamente alimentado com fator de potência unitário, (b) o gerador de indução duplamente alimentado com controle de tensão, (c) o gerador de indução de gaiola de esquilo com compensação baseada em condensadores, e (d) gerador de indução de gaiola de esquilo sem equipamentos auxiliares. Os fatores técnicos analisados são perfil de tensão em estado estacionário, as dinâmicas durante afundamentos e elevações de tensão, correntes de curto circuito, e incremento gradual nas cargas do sistema, para verificar a estabilidade de tensão da rede para pequenas perturbações. É proposta uma estratégia para promover uma integração efetiva de turbinas eólicas em sistemas de potência com altos níveis de penetração considerando diferentes normas de operação da rede para sistemas de transmissão e de distribuição. O objetivo nesta estratégia é o cumprimento dos requisitos para conexão de rede com a combinação de tecnologias, minimizando o valor do investimento. Os efeitos na estabilidade de sistemas de potência da fazenda eólica determinada com a metodologia proposta são comparados com os efeitos de uma fazenda eólica de igual capacidade de energia eólica considerando somente geradores de indução duplamente alimentados com controle de tensão. Para as analises realizadas neste trabalho são considerados os sistemas IEEE de 9 e 30 barras. / Nowadays, wind power is one of the most accepted renewable energy sources, and its penetration in electrical power systems is increasing considerably. Consequently, the participation of wind turbines in electrical power systems has increased and may influence the overall power system behavior. It is therefore important to study the performance of wind turbines in electrical power systems and their interaction with other generation equipment and loads. The main objective of this dissertation is to determine the dynamic performance of different wind turbines technologies connected in electrical system considering different penetration levels and electrical perturbations by simulations performed using a Matlab/Simulink toolbox, SimPowerSystems. The assessed technologies are (a) double fed induction generator with unity power factor, (b) double fed induction generator with voltage control, (c) squirrel cage induction generator with capacitor-based compensation, and (d) squirrel cage induction generator without ancillary devices. The technical factors analyzed are steady-state voltage profile, the dynamics during voltage sags and swells, short-circuit currents, and gradual increase in the system loading, in order to check the network small-disturbance voltage stability. A strategy to promote an effective integration of wind turbines into the power systems with high levels of wind power penetration regarding different grid code requirements in transmission and distribution networks is proposed. The objective in this strategy is fulfilling the grid code requirements with a technology combination, minimizing the invested value. The effects on power system stability of the wind farm, found by the proposed methodology, are compared with the effects that have the same installed capacity of wind power but only considering double fed induction generators with voltage control. The IEEE 9 bus transmission system and the IEEE 30 bus system are regarded for the analysis performed in this work.
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Análise de estabilidade de sistemas de potência em presença de altos níveis de penetração de energia eólica / Analysis of power system stability in presence of high levels of wind power penetration

David Joel Figueroa Cortes 27 June 2014 (has links)
Atualmente, a energia eólica é uma das fontes renováveis mais reconhecidas, e sua penetração em sistemas elétricos de potência está se incrementando consideravelmente. Por consequência, a participação de turbinas eólicas em sistemas elétricos de potência tem se incrementado e pode influenciar o comportamento geral do sistema de potência. Portanto, é importante estudar o desempenho de turbinas eólicas em sistemas elétricos e sua interação com outros equipamentos de geração e cargas. O principal objetivo nesta dissertação é determinar o desempenho dinâmico de diferentes tecnologias ligadas nos sistemas elétricos considerando diferentes níveis de penetração e diferentes perturbações elétricas mediante simulações realizadas usando um toolbox de Matlab/Simulink, SimPowerSystems. As tecnologias avaliadas são (a) o gerador de indução duplamente alimentado com fator de potência unitário, (b) o gerador de indução duplamente alimentado com controle de tensão, (c) o gerador de indução de gaiola de esquilo com compensação baseada em condensadores, e (d) gerador de indução de gaiola de esquilo sem equipamentos auxiliares. Os fatores técnicos analisados são perfil de tensão em estado estacionário, as dinâmicas durante afundamentos e elevações de tensão, correntes de curto circuito, e incremento gradual nas cargas do sistema, para verificar a estabilidade de tensão da rede para pequenas perturbações. É proposta uma estratégia para promover uma integração efetiva de turbinas eólicas em sistemas de potência com altos níveis de penetração considerando diferentes normas de operação da rede para sistemas de transmissão e de distribuição. O objetivo nesta estratégia é o cumprimento dos requisitos para conexão de rede com a combinação de tecnologias, minimizando o valor do investimento. Os efeitos na estabilidade de sistemas de potência da fazenda eólica determinada com a metodologia proposta são comparados com os efeitos de uma fazenda eólica de igual capacidade de energia eólica considerando somente geradores de indução duplamente alimentados com controle de tensão. Para as analises realizadas neste trabalho são considerados os sistemas IEEE de 9 e 30 barras. / Nowadays, wind power is one of the most accepted renewable energy sources, and its penetration in electrical power systems is increasing considerably. Consequently, the participation of wind turbines in electrical power systems has increased and may influence the overall power system behavior. It is therefore important to study the performance of wind turbines in electrical power systems and their interaction with other generation equipment and loads. The main objective of this dissertation is to determine the dynamic performance of different wind turbines technologies connected in electrical system considering different penetration levels and electrical perturbations by simulations performed using a Matlab/Simulink toolbox, SimPowerSystems. The assessed technologies are (a) double fed induction generator with unity power factor, (b) double fed induction generator with voltage control, (c) squirrel cage induction generator with capacitor-based compensation, and (d) squirrel cage induction generator without ancillary devices. The technical factors analyzed are steady-state voltage profile, the dynamics during voltage sags and swells, short-circuit currents, and gradual increase in the system loading, in order to check the network small-disturbance voltage stability. A strategy to promote an effective integration of wind turbines into the power systems with high levels of wind power penetration regarding different grid code requirements in transmission and distribution networks is proposed. The objective in this strategy is fulfilling the grid code requirements with a technology combination, minimizing the invested value. The effects on power system stability of the wind farm, found by the proposed methodology, are compared with the effects that have the same installed capacity of wind power but only considering double fed induction generators with voltage control. The IEEE 9 bus transmission system and the IEEE 30 bus system are regarded for the analysis performed in this work.
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Small wind turbines mounted to existing structures

Duffy, Michael James 20 May 2010 (has links)
Small wind turbines, and especially urban-mounted turbines which require no dedicated pole, have garnered great public enthusiasm in recent years. This enthusiasm has fueled widespread growth among energy conservationists, and estimates predict that the power produced nationally by small wind will increase thirty-fold by 2013. Unfortunately, most of the wind resources currently available have been designed for larger, rural-mounted turbines; thus, they are not well suited for this nascent market. A consequence of this is that many potential urban small wind turbine owners over-predict their local wind resource, which is both costly and inefficient. According to a recent study published by Encraft Ltd., small wind turbines mounted to buildings far underperformed their rural pole mounted counterparts. As a proposed solution to this problem, this project introduces the concept of a Web-based Wind Assessment System (WWAS). This system combines all the necessary resources for potential urban small wind turbine customers into a single web-based tool. The system also presents the concept of a modular wind measurement system, which couples with the WWAS to provide real-time wind data measurements. The benefits of the system include its ease of use, flexibility of installation, data accessibility from any web browser, and expert advice. The WWAS prevents potential clients from investing in a system that may not be viable for their location. In addition, a small wind turbine is designed in this project, which has a unique modular mounting system, allowing the same baseline wind turbine to attach to various structures using interchangeable mounting hardware. This includes such accessible urban structures as street lights, building corners, flag poles, and building walls, among others. This design also utilizes concepts that address some of the challenges associated with mounting small wind turbines to existing urban structures. These concepts include: swept tip blades and lower RPM to reduce noise; vibration suppression using rubber shims; a netted duct to protect wildlife; and a direct-drive permanent magnet generator to ensure low starting torque. Finally, the cost of this system is calculated using off-the-shelf components, which minimize testing and certification expense. This small wind turbine system is designed to be grid-connected, has a 6 foot diameter rotor, and is rated at 1 kW. This design features a unique modular interchangeable mounting system. The cost for this complete system is estimated to be $2,050. If a users' site has an average wind speed of 14 mph (6.5 m/s), this system will generate a return on investment in 8.5 years, leaving over 10 years of profit. The profit for this system, at this sample average wind speed, yields over $4,000 during its 20-year design life, which is a two-fold return on investment. This project has implications for various stakeholders in the small wind turbine market, including designers, engineers, manufacturers, and potential customers. Equally important is its potential role in guiding our future national--even global--energy agenda.

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