Sökresultat:
3699 Uppsatser om Urban wind power - Sida 2 av 247
Kompensering av reaktiv effekt vid vindkraftverk
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.
Simulering av vindkraftverk och närliggande elnät vid Risholmen i Göteborg i SimPowerSystems
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.
Testplattform för nätverks-RTK i syfte att ge en rikstäckande GPS-tjänst med centimeternoggrannhet
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.
Trafiken till Göteborgs södra skärgård - En annorlunda kollektivtrafik
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.
Finansiering av vindkraft : fallstudie av Lau Vind AB
The wind power increase of Gotland as well as other parts of Sweden during the last ten year period has meant that this renewable energy source has increased its share over other fossil sources. The year of 2011 became the first when the wind power produced more energy than an average nuclear reactor. Now that wind power is in an expansive phase, the land issue will be of great interest. Land with good wind resources will be of interest to wind energy developers. The problems that this essay is based on are; how can landowners altering the economic conditions at a wind power establishment? What opportunities and obstacles exist for landowners who choose to set up wind power on their land? The purpose of this essay is to highlight the economic conditions that exist for landowners for the establishment of wind farms, with regard to compensation for the leasing and return on invested capital.
Vindkraftsacceptans i olika etableringsfaser. En jämförelse av acceptansnivån i tre områden inom Mariestads kommun
The purpose of this paper is to contribute to a deeper understanding about the acceptance of wind power. Our basic assumption is that local conditions are important and can explain how the acceptance of change at different stages of establishment. The main purpose is to see if there are differences in the acceptance of wind power in different stages, and examine the factors that influence acceptance. That includes how people in three different areas of study estimates that they value their environment and how it is affected by wind turbines. The project was conducted interdisciplinary geo-targeted and consists of three parts.
Rostfritt stål som ett alternativt material till koppar i tappvattenledningar för bostäder
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.
Wind Power Desalination System
Wind Power desalination for Tunisian markets..
Investeringsbeslut för småskalig vindkraft : en fallstudie
Wind power is one of the sources of renewable energy which has to be developed further in order to lessen our dependence on non renewable sources of energy. It's mainly oil and coal which have to be replaced by green energy. Wind power is already established in many countries, for example Germany, The United States of America and Denmark but it has to be continually developed and expanded to meet the needs of the growing energy consumption in the world. During the last few years many types of small wind turbines have appeared on the market. These small wind turbines are an alternative to the big wind turbines or power generators which demand huge sums of investment money.A new target group can now buy the small wind turbines in order to cover their own usage of electricity.
Utvärdering av svensk vindkraft : Skillnaden mellan skogs- och traditionella placeringar
During the last years commercial Wind Power Turbines (WPT) has become larger regardingto the generator sizes and hub heights. Available hub heights around 100 meters is nowcommon, which has led to profitability for WPT located in forests where there normally are tolow wind speeds. The current knowledgement regarding turbulence and the variation in thewind profile for the outcome of the power production for the WPT in forests is limited.In this Master of Science thesis an investigation concerning forest located wind power plantshas been made. The purpose has been to investigate if plants located in forest perform lesscompared to wind power turbines located at more common locations.The analyses are based on statically material for determining the availability,production/generator size, production/hub height, production/swept area and how thetopography affect the production results.The analyses show that the variation in production result for WPT located in forest comparedto turbines located at other locations is small. The availability is high and the productionresults are good..
Aerodynamisk optimering av vindkraftverks rotorblad med en genetisk algoritm, BEM-teori, och XFOIL
This study presents a methodology that enables the annual average power of a wind turbine to be increased by automatically optimizing it?s airfoil, twist and chord dis- tribution. As a part of the study the software SiteOpt has been developed. This software connects the open source software XFOIL with the blade element momen- tum theory. XFOIL gives lift and drag coefficients which enable the blade element momentum theory to predict the power of a wind turbine at different wind and ro- tational speeds.
Bulleremissioner från vertikalaxlade vindkraftverk
Wind power in Sweden is expanding in response to the government's decision that 49% of Sweden's power should originate from renewable energy sources by the year 2020. Problems with noise and sound emissions related to wind turbines are a constant argument against the wind power expansion and this paper means to examine if vertical axis wind turbines might be a viable alternative to the conventional horizontal design for noise sensitive areas. In order to determine factors like difference in frequency, noise propagation and noise emission level, measurements of both horizontal and vertical axis wind turbines have been completed and the data analyzed with MATLAB. It is shown that there is a difference in how the noise from the two types of turbines propagates due to avariation in the frequency spectra of the emitted sound. It is also shown that vertical axis wind turbines generate a lower sound emission with less intensity inthe lower frequencies..
VINDKRAFTSETABLERINGAR : EN JÄMFÖRANDE STUDIE OM NÄRBOENDES INSTÄLLNING TILL VINDKRAFT OCH VINDKRAFTSETABLERINGAR I SVERIGE OCH BRASILIEN
To achieve a sustainable development, three aspects have to take equal place in the society; environmental, economical and social. To reduce the impact on the environment and the amount of greenhouse gases supplied to the atmosphere, industrialized countries and less developed countries must start cooperating. Also the use of renewable energy sources, like solar, hydro and wind power, have to increase.Wind power has great potential as a future energy supply. It is cost efficient, quickly developed and the resource is abundant and available worldwide.Examinations made in Sweden, indicates that there are difficulties establishing wind power at the same pace as the environmental goals, set by the Swedish government, requires. Mainly because people living nearby potential areas for wind power farms, appeal against the decision.This study aims to investigate differences between how people in Sweden and Brazil look at wind power as a future energy source and at the establishing process.
Vindkraft eller kärnkraft - En jämförelse
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).
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.