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Introduction
Abstract
Wind energy and Planet EarthWinds of the worldFrom windmills to wind turbinesPower, energy and performanceComing up to dateReferences
... In addition, power converters could design to produce or absorb the reactive power in order to run the generators at variable speed, as well as to provide a smooth start for running the turbine mildly up to the rated speed. These are the importance of connecting the power electronics topologies in between synchronous generator and electric grid [148]. The main elements of the synchronous machine strategy are as shown inFig. ...
... As the generator's total power passes through the converters, this strategy is known as full rated or fullscale power conversion. Using this configuration, continuous power can be extracted under variable head, torque surges and switching transients can be reduced [148]. The main elements of the DFIM strategy are as shown inFig. ...
... Both the converters can control independently through dq-axis components and there is considerable flexibility during the allocation of roles in the units. Also, in DFIM using the power converter may admit the facilities like smooth start, smooth power flow, power factor correction, voltage control, torque control and protection of the turbine from stress [148]. The comparison of synchronous machine and doubly fed induction machine in hydro electric energy system are tabulated in Table. 5. ...
... For example, a 0.43 m/s decrease in December surface wind speed at Dun Law produced a 0.68 m/s decrease in hub-height wind speed. These results highlight the sensitivity of the wind speed at hub height to underlying patterns of change at the surface (Lynn [28]). ...
... Changes in the scale parameter followed the trends in mean wind speed. The assessment of monthly wind speed variability is valuable for wind energy planning, due to the disproportionate contribution of high mean wind speeds to power output (Lynn [28]). A 'good-case scenario' for wind power production is generally characterised by a large scale factor and a reduced shape factor www.witpress.com, ...
Climate-forced changes in atmospheric circulation patterns can pose challenges to the development of an efficient wind energy industry. The predicted shifts in circumpolar storm tracks and pressure gradients have a significant effect on local wind resource availability, and impact the wind energy industry in a time of crucial expansion. This study uses Scotland as a case study to model the impact of the SRES A1B climate change scenario on current wind resource availability and wind power potential at two wind farms: Gordonbush (NE Scotland) and Dun Law (SE Scotland). The results predicted an increase of wind resource availability at Gordonbush, and a decrease at Dun Law, leading to corresponding changes in net annual electricity production: a 31.7% increase at Gordonbush and a 31.8% decrease at Dun Law by the year 2040. The majority of observed changes can be attributed to climate-forced changes in atmospheric circulation patterns; however, this research also shows the impact of turbine specifications and site characteristics on the vulnerability of wind power production to climate change. Further work is needed to establish a robust relationship between large-scale climate forcing and local wind resource availability, and to integrate this relationship into the assessment framework of on-shore wind farms around the world.
... The vertical axis wind turbine (VAWT) has been around for years but is starting to get more and more widely used as the world constantly increases its focus on renewable energy sources. The VAWT has the capability of providing a renewable energy source to the domestic, private and small commercial markets as it can be placed on rooftops and areas of turbulent flows with more success than a horizontal axis wind turbine (HAWT) [4][5][6]. The wind turbine power generation efficiency in commercial and domestic applications can significantly be affected by the built up geometry and the interference of adjacent turbines [7]. ...
The main objective of this study is to understand the effect of turbine placement and surrounding structures. Using Urban Green Energy's UGE-4K vertical axis wind turbine and the ANSYS computational fluid dynamics package (CFX), a dynamic fluid analysis was undertaken looking at the wake of the turbine through a variety of different inlet speeds and rotational frequencies to determine suitable flow recovery for optimal placement of subsequent turbines. The results showed that the wake interference is minimal at around 5 times the diameter of the turbine downstream. Results also show that flow recovery was a lot slower to the right of the turbine especially along a line 15° from the centre of the turbine to the right as this is coincident with the vortices generated from the turbines rotation.
... Due to the development of sophisticated technology in the wind industry, which aims to improve the production of electricity, wind energy is an important source of energy in highly developed countries, which is expected to further increase the share of wind energy in the total energy production (Ilkılıc et al., 2011). For example, Denmark, which is the leading country in the world when it comes to installed capacities of wind turbines in terms of the population, produces 20% of electricity from wind energy, 12% is produced in Portugal, and Germany gets as much as 7% electricity from wind energy companies (Lynn, 2012). Although the use of wind energy in the Republic of Croatia has been a subject of systematic research for over 30 years, and the first wind plant was installed in 1988, the first commercial wind plant for electricity production started operating in 2004 on the island of Pag. ...
One of the fundamental tasks of modern power system is finding ways to produce stable and continuous electricity from scarce energy resources. One of the possible solutions is introduction, implementation and improvement of alternative forms of energy such as renewable energy sources, particularly wind energy as an increasingly important energy source which is expected to further increase its share in total electricity production. Numerous methods can be used in assessing the efficiency of wind energy companies, and in the focus of this research is the Data Envelopment Analysis method (DEA), a widely accepted methodology given its interdisciplinary approach and flexibility. This method represents a step forward in the field of renewable energy management, because it provides the possibility to compare the selected companies with the best in the industry (the most efficient) and the possibility of determining sources of inefficiency and, consequently, the possibilities of their elimination.
Keywords: Efficiency, Power Sector, Wind Energy Companies, DEA
... Leading edge roughness of an airfoil causes aggregation of dirt, insect, or ice on the surface, which brings serious issue and affects rotor power output. In extreme cases this can degrade the rotor power output as much as 40%. [8] Department of Electrical Engineering and Renewable Energy Umid M Mamadaminov REE 515 : Energy Engineering I, Fall, 2013 December 6, 2013 3 3 ...
The performance of the aerodynamic system of wind turbine plays crucial role to get maximum torque from wind power, which is key parameter to generate power. While the size of the wind turbine is increasing, it is important to create optimal blade designs to generate higher lift, and provide maximum torque to the generator. In order to generate optimum lift on blades, we need to consider the main factors such as: speed and density of the wind, surface area, lift coefficient. The imaginary cross section of each region from root to tip of the blade is called airfoil. The geometrical shape of an airfoil, including trailing edge, leading edge, chord length, thickness, suction and pressure regions with structural and aerodynamic properties are discussed. When designing the airfoil for wind turbine, the aspects like insensitivity to roughness, high drag to lift ratio, stable stall characteristics must be considered. The most common airfoil designs from several developers were addressed. The recent publications on design structures for wind turbine blades are reviewed. To achieve optimal control aerodynamics and protect environmental damages of blades the morphing concepts, and electro-thermal anti-icing systems tends to be the promising solutions. During the review process, it is found that while designing airfoils there is only a few research was conducted on reducing the noise out of blades, which is a great concern for neighborhoods close to wind farms. In this review we tried avoid from numerical calculations, so the nontechnical audience can use this for reference purposes. The paper gives a brief knowledge about wind turbine aerodynamics, airfoil design and characteristics, blade structure and control from recent publications.
Most products are sold with warranties nowadays, including offshore wind turbines. However, these turbines are complex engineering systems located far away from manufacturing facilities, and as a result their warranties are different from those for consumer products. In this paper, we consider maintenance strategies as the major elements in the warranties for offshore wind turbines, which also include timing requirements, charges and coverage. Warranty cost of turbines is analyzed as the combination of maintenance cost and loss of power production. Uncertainties in the analysis are also discussed.
The paper first deals with the current scenario of the wind energy in India. Wind energy is available without any cost and it does not emit any greenhouse gases. This makes it a great source of energy production for any developing state. The field of wind energy has tremendous scope for innovation, translating to real world applications and tremendous economic opportunity. It is crucially important for India, as our economy continues to evolve, and we must ensure every Indian has access to opportunity, decent jobs and livelihood. For that we will need greater resources. Clean, sustainable, renewable-and equally important, domestic sources of energy are essential to fulfill the potential of India in the coming years and it is certain that wind energy will play a major part in shaping India's future. Wind power has emerged as the biggest source of renewable energy in the world.
IntroductionOverview of Economic Assessment of Wind Energy SystemsCapital Costs of Wind Energy SystemsOperation and Maintenance CostsValue of Wind EnergyEconomic Analysis Methods
Wind Energy Market ConsiderationsReferences
Wind Energy Basics: A Guide to Home and Community-scale Wind Energy Systems
- Paul Gipe
- Manwell