In the pursuit of renewable energy, wind turbines are used to achieve global and national environmental goals. The establishment of this power production has escalated in Sweden, with the aim of phasing out the use of fossil fuels. The electricity generated may be classified as clean, but the infrastructure not only causes landscape changes, but also threatens ecosystems and their services that contribute to human well-being. The effects on ecosystem services are cross-border, and therefore require cooperation at different institutional scales. This study examines documents at national, regional, and local level to map the existing knowledge about wind power's effects on ecosystem services, and how ecosystem services are expressed in planning. A certain common delineation of the effects can be deduced between the different levels of cultural and supporting services. Planning for wind power at the local level has been shown in Piteå municipality to include a few of the ecosystem services that have been defined. However, there is a lack of an in-depth connection between the affected areas, and any ecosystem services these areas can provide.

No description available.

No description available.

No description available.

No description available.

As clean energy demand is on the rise and the wind energy sector in growth, locations with the highest wind potential are becoming of higher interest for wind farm projects, but they are located in colder regions. In cold climates, ice accumulation on wind turbine blades is a serious issue, both in terms of safety and performance. To prevent this, anti-icing technologies, such as Vestas Wind Systems A/S’s, electro-thermal elements are added to wind turbine blades’ construction. This thesis project consists of developing a method to investigate the heat transfer inside and out of wind turbine blades to assess the performance of the anti-icing system and most importantly, verify if it could lead to thermal damage of the blade’s adhesive. In an integrated MATLAB code, the heating requirement is calculated and the 2D conduction modelled based on the wind conditions. The output is a temperature map of the internal structure along with the points with the highest temperature for all adhesive locations, which shows that the selected heating power provided by the heating elements compromises the integrity of the adhesive and doesn’t perform to allow the surface temperature to reach the necessary threshold the prevent icing.

Not much is known if butterflies can get affected by wind turbines. There are different possibilities how they can affect butterflies. How high the risk is that they can get killed by wind turbines and that butterflies might loose habitats by constructions. But there can also be factors that indirectly makes butterflies thrive better in wind farms. More road edges giving the butterflies resources of nectar from herbal plants growing next to the roads is one of them. This study examines if the distance from wind turbines can affect butterflies density and species diversity within and close to the Windfarm of Örbacken. In total 504 individuals of butterflies of 18 species got recorded within distance of 0-1km from wind turbines for three days. Within the distance of 200-500m from wind turbines 228 individuals of 12 species were recorded and had the highest mid value recorded of both the amount species and individuals. There was significance on the number of species being located within areas 200-500m away from wind turbinesand 0-200m from wind turbines. This suggests that the 200-500m areas from these wind turbines that were within the windfarm, may have a higher species diversity of butterflies. The species diversity of butterflies can possibly be affected by less nectar plants and shelter from the wind in areas close to wind turbines compared to areas 200-500m away from them.

The finite element method is applied to an isolated and twisted wind turbine blade which is rotating in a vertical plane to determine its structural dynamic characteristics. The equations of motion are formulated for a rotating beam with flap and lead-lag degrees of freedom subjected to nonsymmetric bending. Using a variational approach, a blade finite clement is developed from these equations of motion. Additionally, expressions are formulated for the elastic strain energy and kinetic energy of a rotating wind turbine blade. Lagrange's equation is applied to these energy expressions and an isoparametric finite element based on three dimensional elasticity and quadratic interpolation functions is developed. Both sets of finite element equations are implemented in a general purpose computer program to solve the structural dynamics eigenvalue problem and results compare favorably with published data for the cases of a nontwisted cantilevered beam both at rest and while rotating. A blade finite element model of a 10KW horizontal axis wind turbine blade is presented and its lowest modes of vibration are calculated for the cases of the blade at rest and in operation at rotor speeds up to 250 RPM. / M.S.

Subsynchronous oscillations (SSO) were an issue that occurred in the past with conventional generators and were studied extensively throughout the years. However, with the rise of inverter-based resources, a new form of SSO emerged under the name subsynchronous control interaction (SSCI). More specifically, a resonance case occurs between Type-3 wind turbines and series compensation that can damage equipment within the wind farm and disrupt power generation. This work explores the types of SSCI and the various analysis methods as well as mitigation of SSCI. The work expands on the concept of frequency scan to be able to use it in an on-line setting with its output data used to mitigate SSCI through the modification of wind turbine parameters. Multiple frequency scans are conducted using PSCAD/EMTDC software to build a lookup table and harmonic injection is used in a parallel configuration to obtain the impedance of the system. Once the impedance of the system is obtained then the value of the parameters is adjusted using the look-up table. Harmonic injection is optimized through phase shifts to ensure minimal disruption of the steady-state operating point and is conducted using Python programming language with PSCAD Automation Library. Simulation results demonstrate the effectiveness of this approach by ensuring oscillations do not grow exponentially in comparison to the regular operation of the wind farm. / Master of Science / Due to climate change concern and the depletion of fossil fuel resources, electrical power generation is shifting towards renewables such as solar and wind energy. Wind energy can be obtained using wind turbines that transform wind energy into electrical energy, these wind turbines come in four different types. Type-3 wind turbines are the most commonly used in the industry which use a special configuration of the classical induction generator. These wind turbines are typically installed in a distant location which makes it more difficult to transfer energy from its location to populated areas, hence, series capacitors can be used to increase the amount of transferred energy. However, these series capacitors can create a phenomenon called subsynchronous control interaction (SSCI) with Type-3 wind turbines. In this phenomenon, energy is exchanged back and forth between the series capacitors and the wind turbines causing the current to grow exponentially which leads to interruptions in service and damage to major equipments within the wind turbine. This work explores SSCI, the tools to study it, and the currently available mitigation methods. It also presents a method to identify the cases where SSCI can happen and mitigates it using adjustable parameters.

This paper aims to investigate some of the diverse perceptions of local populations in Sweden regarding wind energy, focusing on the Ockelbo area. Through a critical discourse analytical perspective, the analysis explores the community's attitudes toward their role in wind energy development and analyzes the presence of discursive elements. The study uses mostly interviews and shows that the local community generally supports wind energy. In contrast to many other areas, the Ockelbo area does not seem to have the individual gap of the Nimby attitude, whereby individuals have a positive attitude toward wind energy in general and a negative attitude toward wind energy in their nearby area. Instead, my informants are generally positive toward wind energy both in general and in Ockelbo. Furthermore, I have related my findings to the theory of environmentality, in which the responsibility for the environment is placed on the population rather than the state through knowledge production about the climate. I argue that elements of environmentality are present in the Ockelbo area through a climate IDF (discursive-ideological formation). This climate IDF frames fossil-free energy as a necessary measure against climate change, that the local population should feel responsible for accepting. This perceived responsibility can be attributed to government rationalities of the state. However, my material shows that the local community does not completely accept responsibility for allowing wind energy. Instead, most of my informants seem to discuss how different aspects of wind energy, such as economic compensation for it, conditions their acceptance for wind energy. Therefore, I do not think that the informants – and perhaps the Ockelbo community in general – are fully internalizing the state’s prioritization of wind energy in areas such as that of Ockelbo.