With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

In today's agriculture efficiency and the capacity of tools and machinery are crucial. In this work we investigate whether it is possible to enhance the capacity of sowing by increasing the work speed of seeders, how seed technology affects seed placement, and if there is any difference between two different brands of seeders and their sow techniques. The seeders we have chosen to compare are Väderstad Rapid drill and Amazon Cirrus drill. The tillage capacity of the seeders and their traction power needs were examined as well.Väderstad Rapid and Amazon Cirrus were tested in a randomized block design with four replicates at three different speeds, 8 km/h, 12 km/h and 15 km/h. The seed placement at the different speeds was examined by dividing the seedbed into four different zones from its surface to its bottom.

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

The scope of this project is to make a comparison of costs associated with wind and nuclear power in order to decide which one of these is the most suitable in the case of an increased demand for electricity. It is also investigated if there are other factors that can influence the choice of energy source.An average cost is calculated in terms of kronor per kilowatt-hour (SEK/kWh) using cost of investment, operation & maintenance and taxes & subsidies. Total investment cost is recalculated to production cost using the annuity method at three different interest rates (6%, 9% and 12%).The comparison is made between three cases of wind power and two cases of nuclear power. For wind power there are two ocean-based (300MW and 100MW installed capacity, respectively) and one land-based (60MW) wind farm. For nuclear power there is one EPR-reactor (1600MW) and one AP1000-reactor (1100MW).

This thesis analyzes the expected profitability in land based wind power plants. The expected profitability is calculated on the basis of a wind power project in Vartofta, Falköping. The information required to calculate the expected outcome is then concentrated to this project, which is in this thesis called project Näs. In project Näs they plan to build three wind power plants, with each an effect of 2 MWh. These wind power plants are very capital intensive investments with a long and uncertain payback time.

Wind power is a growing energy sector in Sweden. However, it still represents only a small part of the total electricity production, about 0.7%. In order to create good conditions and to facilitate the establishment of wind power in Sweden, the government has for example, created a national centre for wind use. The objective has been to reach the governmental goal, which is an expansion of wind power by 10 TWh by year 2015 compared to the level in 2002. The Swedish electricity market was deregulated in 1996 which refers to the introduction of a competitive market in electricity production and trade.

The dependency of fossil fuels has to decrease in order to reduce emissions of green house gases. Wind turbines generate electricity with low environmental impact, but the local opinion in Sweden is sometimes an obstacle to new developments. The acceptance of nuclear power increases at the same time. Mining uranium is once again on the agenda and prospectors are currently drilling for uranium. This cross-sectional study deals with acceptance of wind farms and uranium drilling.

The first commercially produced wind turbines in Sweden are starting to reach theend of their lifetime after approximately 25 years of producing energy. The cost fordismantling the turbines, according to Ardefors et al. (2009), is calculated to be 1-2 %of the total investment of the wind turbines. The purpose of this master thesis is tomap the dismantling process of wind turbines in Sweden and try to find a sustainablesolution for the future.To make sure that a correct dismantling process takes place, and that the financialaspect is covered, a proposal for a financial guarantee is worked upon. A nationalunanimity will be created through a financial guarantee and the risk will be minimalof a third party getting afflicted.Studies of literature and interviews have been carried out.

ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.

Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108 Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both spruce and pine stands and second thinnings only data from spruce stands was collected.

The Swedish Parliament has decided to increase the share of electricity produced by wind power. The same parliament has decided that the Sami have the right to herd reindeer over 50% of the country's land area. In this literature review the potential impact wind power development and associated infrastructure may have on reindeer husbandry conditions are examined. The unique physiology of the reindeer enables it to live out of grazing in the arctic climate in the north of Sweden. For reindeer husbandry to be long-term productive and sustainable, it is important that there is enough land for grazing. The research available on how reindeer are disturbed by human activities such as roads, mines, hikers, etc., clearly indicates that the reindeer avoids areas close to such disturbance.

This master thesis is a study of the Swedish hydropower capacity to balance wind power. The Swedish government has decided that it should be possible to produce 30 TWh from wind power in the year 2020. The Swedish municipalities have to have plans for wind power plants with total yearly generation of 30 TWh. Wind power is an variable energy source that needs to be balanced by other energy sources. In Sweden the Swedish hydropower can be used for balancing a large scale introduction of wind power.

This master thesis has been performed at Solvina in Gothenburg for Skellefteå Kraftand Vattenfall Eldistribution. The aim of it is to investigate the consequences of theinstallation of a wind power plant on the mountain Uljabuouda in the vicinity ofArjeplog. Especially the impacts on voltage and transient stability are examined.Furthermore, the amount of extra strain on the voltage regulation equipment and theneeds for increased regulation capabilities are looked into.The wind power plant is planned to be built by Skellefteå Kraft and connected to a130 kV grid owned by Vattenfall Eldistribution. The work comprehends the followingmain parts:- Theoretical studies aimed at wind turbines and power system stability issues.- Modelling of the type of wind turbines assumed to be built on Uljabuouda.- Simulations of different operation cases and analysis of the simulation results.The results from the simulations show that, as far as voltage stability and extraworkload on tap-changers are concerned, the wind power plant does not, in anysignificant manner, worsen the present conditions. The problem of overloading theline between Arvidsjaur and Vargfors is also minor.