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676 Uppsatser om Wind load - Sida 3 av 46

Vindkraft och landskap

The current debate about environment and climate change has contributed to more andmore investment in alternative energy sources such as wind, solar and biogas. The Swedish Parliament has set the target that wind power should supply 10 TWh in 2015.In Sweden, wind power establishment began in the early 1980s. Since then the development has gained a tremendous momentum. The purpose of this study was to find out what problems wind power brings and what power relations that exists in connection with wind power establishment and how the landscape is affected by windpower construction, focusing on some cases in Falkenberg and Varberg. This study shows that wind power establishment is a very complicated process.

Stormskador i stickvägsgallrade bestånd i sydvästra Sverige :

A storm in January 2005 felled 75 millions cubic metres of forest in South Sweden. Previous studies of wind damage in thinned stands indicated the importance of early thinnings. The risks of wind throw increased by increasing age and height of the stands. Previous studies also indicated increasing risk of wind throw along the strip roads. The aim of the present study was to investigate wind damage in Norway spruce stands in South Sweden in relation to time of the first thinning and different pattern of strip roads (width, length and direction).

Ny stamstation i Yttermalung för anslutning av vindkraft : Nätstudie av olika utföranden i normal- och reservdrift

Since 2004, wind power has had the largest installation of new capacity compared to other energy sources in Sweden. Accommodating new wind power may require strengthening or rebuilding of the existing grid in areas where the grid is already loaded to maximum capacity. This master thesis examine the possibility of a new 400/130 kV substation in Yttermalung, Sweden, with a connection to the two neighboring regional grids in Dalarna and Värmland owned by Fortum. This substation would provide a new connection point to the Swedish transmission system as well as an interconnection of the two, currently separated, regional grids. Different expansion scenarios where a substation with and without series compensation or a phase shifting transformer (PST) to control active power flow were studied.

Ekonomiska innovationer i den gotländska vindkraftsindustrin

Currently there is a controversial debate about that we must reduce our impact on the global warming; therefore both the Government and the local authorities have invested heavily in developing renewable energy in Sweden. The major development on the wind power market can be seen as a result of both the technological development and also on the decision that the Government took in 1996, which opened up the wind power market for private parties.This paper has aimed to examine the types of financial innovations that have arisen from the investments and financing of wind power on Gotland, and what these innovations can contribute to the future development of wind power.The problems that this thesis is based on is; what kind of financial innovations have occurred within investment and financing of wind power? How can these innovations contribute to the continued development of wind power on Gotland? The conclusion of this study shows that respondents and participants have defined a number of financial innovations that have emerged. Where some of the innovations only can be seen as incremental since they are based on continuous improvements, while others can be seen as radical as they are completely new for the context in which they operate. The study has also shown that Gotland has a great potential to produce more renewable electricity, but the development is dependent on the new power lines being built, in order to export electricity to the mainland..

Persontäthet vid utrymningsberäkningar : Köpcentrums persontätheter

The aim of this study is to evaluate whether the value of occupant load is over or under estimated when the Swedish general value for department stores, 0,5 person/m2, is used for dimensioning shopping centers. The data that was analyzed derives from seven shopping centers and one department store. A conservative method was used to calculate the occupant load factor. The analysis shows that two groups can be discerned: one group that is characterized by a lower occupant load factor that does not exceed 0,3 person/m2, and one group with a higher occupant load factor. Shopping centers with a higher occupant load factor are located centrally in large urban areas.

Håller vindkraften vad den lovar?

The purpose of this study is to investigate how much of the estimated annual electric energy production from Swedish wind power that actually was produced, as well as the history of this agreement over time. The aim is to also examine if there are properties that have caused some group of wind power plants to produce more or less, compared to their estimated production. Operational data on wind turbines collected by the Swedish Energy Agency was analyzed. A survey was made among owners of wind power plants with a nominal power of at least 2 MW. Two different methods for normal year correction of production data were used and compared.

Skogsbolagens syn på vindskadeförebyggande åtgärder efter stormen Dagmar

On the night of the 26th December 2011, large parts of southern Norrland were struck by the storm ?Dagmar? that caused serious damage to the forests. In the past 10 years wind damage has become a hot topic after several major storms. Forest companies own 25% of the Swedish forest and thus influenced largely by wind damage. The main purpose of this study was to examine whether forest companies attitude towards preventive wind damage actions were changed after the storm ?Dagmar?. The result was developed by doing interviews with two forestry companies.

En vindkraftparks inverkan på Gävle Energis elnät

The effects from a planned wind farm on the grid utility Gävle Energis electrical grid have been studied. The wind farm is planned to be built in the forest 15 km north of Gävle and will have 23 turbines with rated power from 2 to 2.5 MW, resulting in a total installed power between 46 MW and 57.5 MW. The grid connection will be made at 70 kV. The aim of the analysis was to determine what effects the wind farm would have on the power grid in the form of electrical disturbances (flicker etc.), need for new investment and raised operational cost. To allow the connection of the wind farm technical solutions (new lines, power stations and grid reinforcements) have been constructed.

Vindkraftens påverkan på sin omgivning : En fallstudie

Purpose of this thesis is to study the impact of wind turbines on their surroundings. It also aims to analyze how the communication looks between the authorities, the planner and local residents prior to the establishment of wind turbines in Lännäs/Odensbacken in Örebro, where three wind turbines set up in a group.The results of this survey show that the participants experience themselves not as especially disturbed of the turbines in the form of large noise, shadows, and sleep disturbance indoors and outdoors. Participants felt that no change had taken place on the natural environment (52%) since the turbines became operational. It was 49% of participants had got no information about the establishment of Örebro Municipality, Örebro County Administrative Board or Wind Power Company. Scientists/­experts had the highest confidence of 86%, politicians and the media/journalists had least confidence.

Simulering av elektriska förluster i en vindkraftpark : Utveckling av programvaran Wind Farm ElectricSystem Calculator (WFESC)

When planning new wind farms, the cost for the internal electrical grid is estimated to account for 8-9 % of the total investment cost. On top of that, the cost for accumulated reduced income over several years (due to electrical losses), has to be added. The economic lifespan is relatively long (about 20 years) which means that an error in the loss calculation could lead to a bad decision basis. The accumulated reduced incomes due to electrical losses can be higher than the initial investment cost for the internal electrical grid.Today, Statkraft Sweden is using a template number when estimating the electrical losses in a wind farm. The actual losses are probably lower than the template number which could lead to an unnecessary high loss cost when planning a new wind farm.The aim of this M.Sc.

Vindkraftens framtida scenarier

In several countries that have been early in the development of wind farms, there is today a second hand market for the used wind turbines. The European Union (EU) has established a waste hierarchy in order to minimize throwaway mentality. The second hand market is a part of this as the steps are to minimize, reuse, recycle, extract energy and landfill.In order to promote the development of renewable energy, there are energy certificates for the producers that provide it, wind power being one type of renewable energy. After 15 years the energy certificates for a specific wind turbine are no longer paid, and after that there are several different scenarios for the wind turbine. The scenarios investigated in this bachelor?s thesis are export of the wind turbine to countries that are not as far along as Sweden in their development towards renewable energy, selling in Sweden to individuals, and recycling of the wind turbine, as it mostly consists of metals and therefore is recyclable.

Urban vindkraft : Vindkraftsprojekt Järvafältet & vindkraft i Sverige

Wind power is an energy source that is becoming increasingly popular in Sweden and around the world. The establishment of large wind farms supply and contributes to energy production within grid in search of a more sustainable energy production. Wind power is becoming more popular and opens up new areas of implementation. More cities are starting to use small-scale urban wind power, everything from full-scale work for a little less work adapted to the villas. Sweden has high goals regarding the production of green electricity and the work which deals with the conditions Sweden plays in achieving those goals.

Accessoarer för framtidens kontor

This thesis investigates if a system for small scale electricity production located in anurban environment can be profitable. The work has been divided up into two parts,one extensive literature study and one case study. The purpose of the literature studywas to investigate the area, resulting in a choice of which technology to be studied indepth in a case study.In the case study a system containing small scale wind turbines and photovoltaicsmounted on Gränby Centrums roof was examined. From data containing wind power,wind direction and total irradiation, possible production from a system weresimulated. Three products of each technology were examined in the simulations.From the simulated production an economic analysis was carried out, this toinvestigate if a system is profitable.

Strömningen i och över en skog : utvärdering av en 'mixing-layer' hypotes

A new theory for predicting the windprofile over a canopy has been evaluated. The theory was first presented by Harman and Finnigan (2007). The theory relies on the forming of a mixing-layer above the canopy, due to different mean wind in and above the canopy. Characteristics from both mixing-layer and Monin Obukhov similarity theory have been used to develop the governingequations that give the wind profile. The theory has been used to calculate wind profiles for sixdifferent atmospheric stabilities.

Eurokoder : en jämförelse mot BKR

In Sweden there are currently two separate guidelines you may use whenperforming calculations on frameworks, BKR and the Eurocodes. Although at theend of 2010 you are not allowed to use BKR any longer and only the Eurocodeswill be viable. The aim of this thesis is to explain how the Eurocodes and EKS work and alsohow they compare to the current guideline BKR. Similarities and differencesbetween these guidelines are also discussed so that the reader will get a betterunderstanding of how the Eurocodes are applied. The areas discussed are asfollows:Principles and adviceSafety ClassesSymbols and IndexesLifespanLoads and partial coefficientThe thesis also deals with the impact that this transition into a new guideline willhave on corporations, guideline costs, education and computer software. As anexample a rough estimate on what costs this transition will create on a companywith 20 employees is also included. Calculations have been performed in order to investigate how the design valuesdiffer between the two guidelines, the Eurocodes and BKR.

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