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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.
771

Havsbaserad vindkraft i svensk media : En kvalitativ studie om konflikter och argument (för och emot) gällande havsbaserad vindkraft i Sverige

Bäcklund, William January 2023 (has links)
The aim with this study is to analyze and try to understand the arguments and conflicts associated with the planning and development of offshore wind power in Sweden, and to study various media articles and their significance for offshore wind power in Sweden. A qualitative method has been applied in the form of a media analysis. The material for the study is based on diverse types of articles from the media in the form of news articles, commentaries, and debate articles. The articles I have chosen to analyze come mostly from the most popular news editors in Sweden; "Aftonbladet", "Dagens Nyheter" and "Svenska Dagbladet". There are also news articles from local newspapers so that even smaller local events can be captured and studied. Further in this study, media such as Swedish Radio and SVT Nyheter have been applied where shorter news items can be examined. This result shows how the opposition and arguments for and against offshore wind power are played out in the media and that the media can function as an information provider for offshore wind power linked to the planning and expansion of offshore wind power in Sweden. Many opinions want to highlight the negative consequences of offshore wind power, mainly from a local point of view. In some cases, opposition is also about preserving nature's values and not making interventions in nature that affect biodiversity, but this is something that "NIMBY" may have led to. That media coverage of the topic is largely based on informing people about ongoing projects and preparing press releases with important information about the projects, as well as acting as an information channel.
772

WIND POWER PROJECT DEVELOPMENT: A MULTI-CRITERIA DECISION ANALYSIS FRAMEWORK FOR SUBCONTRACTORS’ EVALUATION

Chetouani, Yassine January 2022 (has links)
The Swedish Wind Energy Association (SWEA, 2019) reported the wind power project's total investment cost between 2017 and 2021 was over SEK 72 billion. They predicted that at project completion, the total production will be approximately 22.4 TWh per year. Due to project size, complexity, and long-term contracts commitments, almost all wind power project developers outsource some or most of their project activities to different subcontractors, after which they perform monitoring activities of the project process. Therefore, the pre-qualification stage and subcontractors’ evaluation become essential parts of every project. Most corporates and authorities are usually awarding projects to subcontractors with offers based on the most competitive price advantage. This approach results in high risks that can affect the delivery time, the overall cost, and the quality of wind power projects.This research paper aims to use a multi-criteria analysis to identify and select the most adequate subcontractor. To achieve the research purpose, a sample of five subcontractors nominated by a windpower developer were evaluated in a selection phase under nine criteria: (1) management capability, (2) product or service quality, (3) planning and capabilities, (4) quality assessment,(5) environmental management, (6) health and safety measures, (7) financial strength, (8) contract insurances and guaranties, and (9) cost. After the evaluation and the ranking of companies, a result of the most adequate subcontractor for the project offer was presented. At the end of this study, a comparison analysis was followed at the final stage which compared the method with a similar procurement approach used by one corporate where it showed that this paper’s method can uncover critical aspects with subcontracts which can alter the selection process.
773

Load Hindcasting: A Retrospective Regional Load Prediction Method Using Reanalysis Weather Data

Black, Jonathan D 01 January 2011 (has links) (PDF)
The capacity value (CV) of a power generation unit indicates the extent to which it contributes to the generation system adequacy of a region’s bulk power system. Given the capricious nature of the wind resource, determining wind generation’s CV is nontrivial, but can be understood simply as how well its power output temporally correlates with a region’s electricity load during times of system need. Both wind generation and load are governed by weather phenomena that exhibit variability across all timescales, including low frequency weather cycles that span decades. Thus, a data-driven determination of wind’s CV should involve the use of long-term (i.e., multiple decades) coincident load and wind data. In addition to the challenge of finding high-quality, long-term wind data, existing load data more than several years old is of limited utility due to shifting end usage patterns that alter a region’s electricity load profile. Due to a lack of long-term data, current industry practice does not adequately account for the effects of weather variability in CV calculations. To that end, the objective of this thesis is to develop a model to “hindcast” what the historic regional load in New England would have been if governed by the conjoined influence of historic weather and a more current load profile. Modeling focuses exclusively on summer weekdays since this period is typically the most influential on CV. The summer weekday model is developed using multiple linear regression (MLR), and features a separate hour-based model for eight sub-regions within New England. A total of eighty-four candidate weather predictors are made available to the model, including lagged temperature, humidity, and solar insolation variables. A reanalysis weather dataset produced by the National Aeronautics and Space Administration (NASA) – the Modern Era Retrospective-Analysis for Research and Applications (MERRA) dataset – is used since it offers data homogeneity throughout New England over multiple decades, and includes atmospheric fields that may be used for long-term wind resource characterization. Weather regressors are selected using both stepwise regression and a genetic algorithm(GA) based method, and the resulting models and their performance are compared. To avoid a tendency for overfitting, the GA-based method employs triple cross-validation as a fitness function. Results indicate a regional mean absolute percent error (MAPE) of less than 3% over all hours of the summer weekday period, suggesting that the modeling approach developed as part of this research has merit and that further development of the hindcasting model is warranted.
774

Empowering Wind Power Development Through Tiering : Investigating the Role of Regional Governance in Värmland / Tiering som en möjliggörande faktor för vindkraftsutbyggnad : En analys av regional styrning vid vindkraftplanering i Värmland

Lundmarck, Patrick January 2023 (has links)
In the light of the on-going climate emergency and energy crisis, wind power has been described as a rapid pathway towards increasing the share of renewable energy as well as electricity production. However, time consuming and complex permitting processes has been a central obstacle for the transition to take place. Municipalities have a strong influence over land use planning in Sweden and despite the urgent need to increase renewable energy production, few wind power projects are permitted.  Previous research has underlined capacity building between local and regional levels as a pathway to strengthen local institutions and stimulate wind power developments. Following Arts et al. definition of ‘tiering’ as the deliberate, organized transfer of information and issues from one level of planning to another, collaboration between different tiers is described as fundamental for successful projects. By analysing data from interviews, documents, and observations, this study has investigated what role collaboration between tiers plays in the Regional Wind Power Analysis in Värmland, and how the project could lead to more effective planning processes for wind power. The results indicate that the Regional Wind Power Analysis can strengthen the planning process for wind power by raising awareness and stimulating knowledge building between important stakeholders, which consequently can make it easier to understand how and potentially where to engage in wind power planning. In line with previous research, the study also illustrates the potential governing role the County Administration Board can play for coordinating projects and building institutional capacity for inter-municipal and inter-regional issues, including wind power. Even though the project has been appreciated, if financial incentives remain scarce, there will not be enough reason to engage in wind power planning locally. / I ljuset av den pågående klimat- och energikrisen har vindkraft lyfts fram som en möjlig väg framåt för att snabbt kunna öka elproduktionen och ställa om till en förnybar energisektor. Trots det så har osäkra tillståndsprocesser blivit ett allt större problem för vindkraftsaktörer, vilket utgör ett tydligt hinder för att bygga fler vindkraftsparker. Kommunerna har med sitt planeringsmonopol ett stort inflytande över markanvändningen i Sverige, och trots behovet av en snabb och grön energiomställning så säger kommunerna allt oftare nej till vindkraft. Tidigare forskning har pekat ut kapacitetsstödjande åtgärder mellan lokal och regional nivå som en möjlig lösning för att bistå kommunerna i vindkraftsärenden och således öka vindkraftsproduktionen.  Med avstamp i Arts et al. definition av tiering som en medveten, organiserad överföring av information och frågor från en planeringsnivå till en annan har samverkan mellan olika nivåer beskrivits som en stöttepelare för lyckade planeringsprojekt. Genom intervju-, dokument och observationsstudier har denna studie undersökt vilken roll samverkan mellan olika planeringsnivåer spelar i den regionala vindkraftsanalysen i Värmland och vidare hur projektet kan främja vindkraftsplanering. Resultatet visar att den regionala vindkraftsanalysen kan stärka planeringen för vindkraft genom att öka medvetenheten och bygga upp en förståelse hos olika aktörer, vilket kan göra det lättare att förstå hur och potentiellt var det är lämpligt att utveckla vindkraft. I linje med tidigare forskning pekar denna studie också ut Länsstyrelsen som en viktig aktör för att leda projekt och bygga institutionell kapacitet där olika aktörer kan samverka för att hantera mellankommunala och regionala frågor, så som vindkraftsärenden. Trots att vindkraftsanalysen kan leda till ökad samverkan och är ett uppskattat projekt, så visar studien att bristen på ekonomiska incitament lokalt leder till få anledningar för kommunerna att vilja engagera sig i vindkraftsutbyggnad.
775

INVESTIGATING THE FEASIBILITY AND THE POLICIES FOR WIND POWER REPOWERING IN SWEDISH MUNICIPALITIES

Roško, Samuel January 2023 (has links)
Transitioning to a low-carbon energy system includes deploying renewables such as wind power, which has been installed in Sweden since the 1980s. After a 20 to 25-year lifetime, a wind turbine´s end-of-life options come into play, therefore many of the turbines deployed in Sweden prior to 2011 will reach this mark by 2035. To utilize a site´s wind resource in the best possible way, full repowering is considered in an assessment of seven case studies in Swedish municipalities with the highest deployed pre-2011 wind power capacity. Each case study uses various turbine models to evaluate full repowering scenarios. The most profitable scenarios are estimated through the investment over production (I/P) value and the break-even electricity price. The identified municipalities’ comprehensive plans are reviewed in terms of repowering strategies and wind power deployment guidelines. Only three out of seven investigated municipalities consider repowering in comprehensive plans, with Gotland being best prepared in terms of repowering strategies. Strömsund and Eslöv mention repowering in their comprehensive plans with no specific guidelines. Restrictive policies were identified in the municipality of Laholm, where the maximum total height of turbines is 150m, decreasing the potential annual energy production of an analyzed case study by 64%. The municipalities of Falkenberg, Laholm, Piteå, and Åsele do not include repowering in their comprehensive plans. All the simulated repowering scenarios increased the annual energy production of the identified sites by up to 73%, lowered the number of turbines by up to 70%, decreased the wake losses by up to 77%, and decreased the noise level by 10% while increasing the potential shadow flicker by 19%. The results of the study indicate a possible divide between the intention of the municipalities of Eslöv, Strömsund, and Åsele to maximize energy production from wind power at each exploited site on the one hand and the business cases that developers face on the other. The results suggest the turbines which increase energy production the most at already developed sites, are not necessarily the ones with the lowest investment over production (I/P) value or the lowest break-even electricity price.
776

Hosting Capacity Methods Considering Complementarity between Solar and Wind Power : A Case Study on a Swedish Regional Grid

Andersson, Emma, Abrahamsson Bolstad, Maja January 2023 (has links)
The demand for electrical power is growing due to factors such as population growth, urbanisation, and the transition from fossil fuels to renewable energy sources. To be able to keep up with the changes in electricity demand, the Swedish power grid must connect more renewable power generation, but also  increase its transmission capacity. Traditionally, power grids are expanded to increase the transmission capacity which requires a lot of time and investments. In order not to hinder the electrification of society, it is important to adequately estimate the current transmission capacity and plan the expansions accordingly. In the past, the generation of electrical power was primarily based on dispatchable energy sources, and the planning of new connections to the grid was assessed according to the stable and controllable nature of the electricity supply. However, renewable sources like solar and wind power are affected by weather variations. Therefore, the traditional methods of planning the power grid are no longer sufficient. Instead, there is a need to develop and implement new methods that account for the variable nature of renewable energy sources, and also the possible complementarity between different renewable power sources. This can possibly allow more connection of renewable power generation to the grid, without the need of expanding it. The aim of this thesis is to investigate two different methods for analysing how much renewable power generation that can be connected to the power grid, so-called hosting capacity methods. The first method is a deterministic method which is traditionally used in power system analyses since it is a fast, simple and conservative method. This method does neither consider the intermittent nature of solar and wind power, nor any complementarity. The second method is a time series method which considers the complementarity and intermittency of solar and wind power but requires much data. The methods are compared in regards to assessed hosting capacities, risks and reliability of results. The study is performed on a regional grid case in the middle of Sweden. Solar and wind power plants with different capacities are modeled at ten buses in the power grid. The power grid is analysed in PSS/E with loading of lines and voltage levels determining the assessed hosting capacities. A correlation map presenting the temporal correlations of solar and wind power over the grid case area is also created in order to evaluate the complementarity in the area and its possible effects on the assessed hosting capacities.  The results show that the time series method is more reliable than the deterministic method. This is due to the difficulties in identifying accurate worst case hours that are used for the deterministic method. The time series method is also preferred as it considers complementarity between solar and wind power. However, the correlation map argues that the grid case area has weakly positive correlations, meaning low complementarity between solar and wind power. This suggests that the differences in hosting capacity between the two methods are more likely dependent on the temporal variations in existing load and power generation. The differences in assessed hosting capacity between the ten buses in the power grid are probably not due to the local complementarity either, but rather the structural differences of the grid in terms of components, local loads and existing power generation.
777

A TECHNO-ECONOMIC FEASIBILITY STUDY OF OFFSHORE WIND-HYDROGEN PRODUCTION IN SOUTHERN SWEDEN

Hansson, Carol January 2022 (has links)
To meet the energy targets and improve the lack of power and higher prices in southern Sweden, the amount of electricity must increase, and alternative fuel sources be introduced. This thesis examines the techno-economic feasibility of offshore wind-hydrogen production in southern Sweden, depending on whether an onshore- or offshore hydrogen system is used, and how grid connection subsidies would affect this. New research and development regarding the subjects were analyzed and reviewed. A project that has currently applied for a permit in southern Sweden, Skåne Offshore Wind Park, was used as a case study where the information from the review and data from similar parks were used to determine the cost and production for the two different systems. The costs were then adjusted according to the three different subsidy scenarios: current with no subsidies, partial with sea cable and transformer costs removed, or a full subsidy scenario where only the internal grid cost remained to achieve feasible levelized costs for electricity and hydrogen based on a discount rate of 6% and a lifetime of 25 years. Finally, a sensitivity analysis was performed.   The results showed that market competitive electricity prices are only achieved with an onshore hydrogen system- and only if a full subsidy is introduced or if a best-case scenario is applied. In a worst-case scenario, no competitive electricity prices were achieved. For the offshore hydrogen system, the extra fuel system is too inefficient for electricity production. For hydrogen, prices were achieved within a reasonable price range of green hydrogen for all scenarios, where the onshore hydrogen system was 4% more advantageous. In a best-case scenario, competitive values ​​even against blue hydrogen were achieved for the offshore hydrogen systems and for the full subsidy onshore hydrogen system. For hydrogen, the offshore hydrogen system's hydrogen prices were competitive regardless of subsidies, however this system had the highest CAPEX and OPEX costs.   The results of the study underline the need for fixed conditions but also the necessity of introducing a full subsidy for the grid connection cost - or best-case scenario conditions - to encourage further offshore wind power development.
778

Multikriterie-analys med hjälp av medborgardialog : En studie för lokalisering av havsbaserad vindkraftpark

Engström, Anton, Kallio, Marcus January 2022 (has links)
Rådande situation med klimatförändringar och oroligheter i Europa kräver åtgärder för att kunna skifta från fossila bränslen och energikällor till mer hållbara alternativ. Elförbrukningen väntas öka signifikant i Sverige och ett alternativ för att tillgodose hållbar energi och klimatmål är utvecklingen av vindkraft. Satsningar sker alltmer på havsbaserad vindkraft eftersom det är goda vindförhållanden och mindre påverkan för människor i närområdet eftersom vindkraftverken kan placeras långt från kusten. I många fall är det projekteringsföretag, kommuner och politiker som beslutar placeringen av vindkraftverken. Ett problem som uppstår är när allmänheten anser att det uppstår störningar på grund av att vindkraftverken placeras i dess närhet och att de inte får deltaga i planeringsprocessen. Studien syftar till att hitta lämpliga platser för havsbaserad vindkraft utifrån metoderna medborgardialog och multikriterie-analys för att kunna integrera medborgarinflytande i planeringsprocessen. ”Mjuka kriterier” som ofta tas upp i sammanhang om vindkraft har tagits i beaktning och har skickats ut i en enkätundersökning för att få in vad som är viktigast för invånare i Gävle kommun. Dessa innefattar hur stor påverkan respondenterna uppfattas kunna påverkas av som till exempel ljud, utsikt och buller. Utifrån dessa kriterier fick respondenterna rangordna samtliga för att skapa en viktning till multikriterie-analysen. Beskrivande statistik på vad respondenterna är oroliga för att påverkas av vid byggnation av havsbaserad vindkraft togs fram för att styrka studiens legitimitet. Resultatet visar att det är en stor majoritet av respondenter som är positivt inställd mot vindkraft och att respondenter inte uttrycker någon signifikant oro. Metoden MKA med viktning av rank sum weights användes för att skapa olika kartor faktor- och restriktionskartor baserat på respondenternas svar samt en teknisk analys utifrån en omfattande litteraturstudie. Den tekniska analysen använder kriterier som havsdjup, avstånd till kraftstationer och hamnar som inte klassas som ”mjuka kriterier”. Resultatet visar att medborgardialogen påverkar vilken lokalisering vindkraftverken får jämfört med den tekniska analysen. En slutgiltig karta skapades för att visa var någonstans vindkraftparken kan hamna om båda delarna tillgodoses. Studien tyder på att ett större underlag för medborgardialog kunnat ge ett tydligare resultat samt att viss typ av data hade krävts för en ordentlig teknisk analys. Det nya som denna studie har utvecklat är en metod för att föra en medborgardialog gällande havsbaserad vindkraft och kvantifierat invånarnas åsikter till geografiska data. / The current situation with climate change and unrest in Europe requires measures to be able to switch from fossil fuels and energy sources to more sustainable alternatives. Electricity consumption is expected to increase significantly in Sweden and an alternative for meeting sustainable energy and climate goals is the development of wind power. Investments are increasingly being made in offshore wind power because it has adequate wind conditions and less impact for people in the immediate area since the turbines can be located far from the shore. In many cases, it is corporations, municipalities and politicians who decide on the location of the wind turbines. A problem that arises is when the public considers that disturbances occur due to the fact that the wind turbines are located in their vicinity and that they are not offered the possibility to participate in the planning process. The study aims to find suitable places for offshore wind power based on the methods citizen dialogue and multi-criteria analysis to be able to integrate citizen influence in the planning process. "Soft criteria" that are often raised in the context of wind power was taken into account and was included in a survey to address what is important for residents of Gävle municipality. These include how much impact the respondent is perceived to be affected by, such as sound, view and noise. Based on these criteria, the respondents were allowed to rank all of them in order to create a weighting for the multi-criteria analysis. Descriptive statistics based on what the respondents are worried about being affected by during the construction of offshore wind power were produced to prove the legitimacy of the study. The results show that a large majority of respondents are positive towards wind power and that respondents do not express any significant concern regarding the construction of offshore wind power. The MCA method with weighting method rank sum weights was used to create different factor and constraint maps based on the survey answers and a technical analysis based on an extensive literature study. The technical analysis uses criteria such as bathymetry, distance to power stations and ports that are not classified as "soft criteria". The results show that the citizen dialogue affects the location of the wind turbines compared to the technical analysis. A final map was created to show where the wind farm could end up if both parts are met. The study indicates that a more comprehensive citizen dialogue could have given a more concise result and that a certain type of data had been required for a more thorough technical analysis. The new thing that this study has developed is a method for conducting a citizen dialogue regarding offshore wind power and quantifying the inhabitants' opinions to geographical data.
779

Motstående miljöintressen vid markanvändningen i Sápmi : En kvalitativ studie med visst fokus på Malå sameby om potentiella markkonflikter mellan vindkraftsprojekt och samerna

Kocak, Melike, Vukalic, Medina January 2022 (has links)
In 2017, Sweden adopted a climate policy framework to meet zero emissions of greenhouse gases until the year 2045. In order for this to happen, Sweden must undergo a so-called green transition in which wind power could play a significant role. On the other hand, this development is not as indisputable as it seems, as it encounters resistance from other parties who share legitimate interests, for the land use, namely the Sami. This essay will therefore highlight the possible land use conflicts that may arise during the establishment of the wind turbines. The essay will be based on the collected empirical evidence that was done via interviews with the various parties, the wind power industry, and representatives from the reindeer herding Sami. This conflict over the land use can be restated as a wicked problem. That is, these two in a sense equally valid claims to the land use cannot easily be resolved as there exists no hierarchy of which claim is more important, or which claim is “right” which is also one of the main frameworks that will be analyzed in this essay together with potential environmental justice where this concept is discussed from three different perspectives. The results of this study show that the indigenous people feel that the menace from the wind farms not only threatens reindeer husbandry but also their culture and that these conflicts are due to too little consideration being given to it. Even though the Sami villages are compensated for the encroachments, the lost reindeer pastures are something they feel cannot be fully compensated. The conclusion refers that the main and alternatively the best solution to this insidious problem is to have an early dialogue with both parties and that a greater understanding needs to happen for the Sami to realize their importance. / Sverige antog 2017 ett klimatpolitiskt ramverk för att klara nollutsläpp av växthusgaser fram till år 2045. För att det ska ske måste Sverige genomgå en så kallad grön omställning där vindkraft kan spela en betydande roll. Dessutom är denna utveckling inte så obestridlig som den verkar, eftersom den möter motstånd från andra parter som delar legitima intressen, för markanvändningen, nämligen de renskötande samerna. Denna uppsats kommer belysa de möjliga markanvändningskonflikter som kan uppstå vid etableringen av vindkraftverken. Uppsatsen kommer att baseras på den insamlade empiri som gjorts via intervjuer med de olika parterna, vindkraftsindustrin och representanter från renskötande samer. Denna konflikt om markanvändningen kan återges som ett lömskt problem (wicked problem). Det vill säga att dessa två i en mening lika giltiga anspråk på markanvändningen kan inte lätt lösas eftersom det inte finns någon hierarki över vilket påstående som är viktigast, eller vilket påstående som är "rätt", vilket också är en av huvudramarna som kommer att analyseras i denna uppsats tillsammans med potentiell miljörättvisa där detta koncept diskuteras ur tre olika perspektiv. Resultaten av denna studie visar att urbefolkningen upplever att hotet från vindkraftsparkerna inte bara hotar rennäringen utan även deras kultur och att dessa konflikter beror på att det tas för lite hänsyn till det. Även om samebyarna kompenseras för intrången är de förlorade renbetesmarkerna något som de upplever inte kan kompenseras fullt ut. Slutsatsen visar att den främsta och alternativt bästa lösningen på detta lömska problem är att ha en tidig dialog med, och att en större förståelse behöver ske utifrån båda parter.
780

MULTI-CRITERIA DECISION ANALYSIS FOR FUTURE OFFSHORE WIND FARMS IN ITALY – A DEVELOPED METHODOLOGY TO EVALUATE OFFSHORE WIND PROJECTS

Virano, Chiara January 2023 (has links)
Despite currently having only one operational offshore wind farm, Italy holds a significant potential for the future development of this technology. The Global Wind Council placed Italy second in its ranking of the world’s 30 most attractive markets regarding the potential of future offshore development, attracting the attention of numerous developers. The characteristics of the Mediterranean Sea, with its high water depth, make it possible to develop mainly floating technology. Furthermore, the absence of severe weather events, present in the Atlantic and the North Sea instead, enhanced security and contributed to the reduction of investment risks. Currently, there are many new wind farms awaiting approval, as evidenced by Terna, the Italian Transmission System Operator (TSO), which announced that by the end of October 2022 the connection requests for offshore wind projects had reached 95 GW. This thesis aims to develop an approach able to compare several projects from multiple perspectives. Specifically, the thesis applies the Multi-Criteria Decision Analysis to evaluate and compare four floating offshore wind farms which are now in the permitting phase. The projects are located off the coast of Sardinia, one of the most promising locations in the Mediterranean Sea for offshore wind installation. The evaluation of the future wind farms is conducted using eleven criteria, each assigned a different weight based on the preferences of six stakeholder groups. The tool used to rank the criteria is the PROMETHEE tool. The results demonstrate that each stakeholder group ranks the projects differently based on their respective preferences. Finally, an overall ranking of the wind farms is derived, identifying the most and least favorable projects.

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