RBI Optimization of Offshore Wind Turbines

DEFF Research Database (Denmark)

Ramírez, José G. Rangel; Sørensen, John Dalsgaard

2009-01-01

methods for oil & gas installations, a framework for optimal inspection and maintenance planning of offshore wind turbines is presented. Special aspects for offshore wind turbines considered are the fatigue loading characteristics where usually the wind loading are dominating the wave loading, wake......Wind turbines for electricity production have increased significantly the last years both in production capability and size. This development is expected to continue also in the coming years. Offshore wind turbines with an electricity production of 5-10 MW are planned. Typically, the wind turbine...... support structure is a steel structure consisting of a tower and a monopile, tripod or jacket type foundation. This paper considers aspects of inspection and maintenance planning of fatigue prone details in jacket and tripod type of wind turbine support structures. Based on risk-based inspection planning...

The 1.5 MW wind turbine of tomorrow

Energy Technology Data Exchange (ETDEWEB)

De Wolff, T.J.; Sondergaard, H. [Nordtank Energy Group, Richmond, VA (United States)

1996-12-31

The Danish company Nordtank is one of the pioneers within the wind turbine industry. Since 1981 Nordtank has installed worldwide more than 2300 wind turbine generators with a total name plate capacity that is exceeding 350 MW. This paper will describe two major wind turbine technology developments that Nordtank has accomplished during the last year: Site Optimization of Nordtank wind turbines: Nordtank has developed a flexible design concept for its WTGs in the 500/600 kW range, in order to offer the optimal WTG solution for any given site and wind regime. Nordtank`s 1.5 MW wind turbine: In September 1995, Nordtank was the first company to install a commercial 1.5 NM WTG. This paper will document the development process, the design as well as operations of the Nordtank 1.5 MW WTG.

Alcoa wind turbines

Science.gov (United States)

Ai, D. K.

1979-01-01

An overview of Alcoa's wind energy program is given with emphasis on the the development of a low cost, reliable Darrieus Vertical Axis Wind Turbine System. The design layouts and drawings for fabrication are now complete, while fabrication and installation to utilize the design are expected to begin shortly.

Wind Turbine Acoustics

Science.gov (United States)

Hubbard, Harvey H.; Shepherd, Kevin P.

2009-01-01

Wind turbine generators, ranging in size from a few kilowatts to several megawatts, are producing electricity both singly and in wind power stations that encompass hundreds of machines. Many installations are in uninhabited areas far from established residences, and therefore there are no apparent environmental impacts in terms of noise. There is, however, the potential for situations in which the radiated noise can be heard by residents of adjacent neighborhoods, particularly those neighborhoods with low ambient noise levels. A widely publicized incident of this nature occurred with the operation of the experimental Mod-1 2-MW wind turbine, which is described in detail elsewhere. Pioneering studies which were conducted at the Mod-1 site on the causes and remedies of noise from wind turbines form the foundation of much of the technology described in this chapter.

Report on the safety of wind turbines installations; Rapport sur la securite des installations eoliennes

Energy Technology Data Exchange (ETDEWEB)

Guillet, R.; Leteurtrois, J.P.

2004-07-01

This report aims to study the regulatory framework governing the safety of wind turbines and proposes improvement actions. It concerns the wind turbines risk assessment, the technical bases of the wind turbines safety, the regulation relative to the safety and possible evolutions. (A.L.B.)

Danish wind power in Brazil. Part 2. Experience with Danish 75 kW wind turbine - the first modern turbine in Brazil

Energy Technology Data Exchange (ETDEWEB)

Husted Rich, N; Kildemoes Moeller, T

1996-04-01

In June of 1992, the first grid-connected wind turbine (75 kW, 12 m/s) in Brazil was installed in the complex terrain of the island of Fernando de Noronha in the northeastern part of the country. The objective was to install a Danish wind turbine in order to encourage the use of wind energy in Brazil and to demonstrate Danish wind technology with the view of opening up the Brazilian market for Danish windmills. It is claimed that the turbine, backed up by the media, attracted a certain amount of attention despite problems caused by the weakness of the electric grid on the island. The market in Brazil is still not ready for wind turbines and responsibility for any future wind energy policy is held by the political decision makers, so it is recommended that further demonstration projects be set up. The document presents a general view of the wind conditions and a view of the local electric power system with the aim of improving the potential for further installation of Danish wind turbines on the island. It proved difficult to obtain information on the performance of the windmill due to frequent rotations in the hierarchy of the state utility company CELPE, and the highly bureaucratic structure in general. It is stated that CELPE intends to install two more wind turbines on the island and that this could be a proof of recognition that technical problems that arose were caused by the unsatisfactory grid structure on the island and not related to faults in the wind turbine itself, and also a proof of their confidence in the idea of wind energy as a reliable source of electricity production. (AB)

Feasibility study of offshore wind turbine installation in Iran compared with the world

Energy Technology Data Exchange (ETDEWEB)

Mostafaeipour, Ali [Industrial Engineering Department, Yazd University, Yazd (Iran)

2010-09-15

Renewable energies have potential for supplying of relatively clean and mostly local energy. Wind energy generation is expected to increase in the near future and has experienced dramatic growth over the past decade in many countries. Offshore winds are generally stronger and more constant than onshore winds in many areas. The economic feasibility for utilization of offshore wind energy depends on the favorable wind conditions in the area. The present paper analyses offshore wind speed in global scale and also studies feasibility of introducing this technology for harnessing wind in Persian Gulf, Caspian Sea, Urmia Lake and Gulf of Oman. Wind speed data were collected from different sources. The ocean surface winds at a 10 m height from satellite passes as processed by NOAA/NESDIS, from near real-time data collected by NASA/JPL's Sea Winds Scatterometer aboard the QuikSCAT. Development of renewable energy is one of priority research goals in Iran. There are many installed wind turbines in suitable regions like Manjil and Binalood, but there has not been any offshore wind installation yet in Iran. It is suggested that policy makers to invest and pay more attentions toward harnessing renewable energy sources like offshore wind in Persian Gulf and Gulf of Oman in southern parts of Iran. (author)

Evaluation of different turbine concepts for wind power

Energy Technology Data Exchange (ETDEWEB)

Eriksson, Sandra; Bernhoff, Hans; Leijon, Mats [Swedish Centre for Renewable Electric Energy Conversion, Division for Electricity and Lightning Research, Box 534, 751 21 Uppsala (Sweden)

2008-06-15

Every year the number of installed wind power plants in the world increases. The horizontal axis wind turbine is the most common type of turbine but there exist other types. Here, three different wind turbines are considered; the horizontal axis wind turbine and two different concepts of vertical axis wind turbines; the Darrieus turbine and the H-rotor. This paper aims at making a comparative study of these three different wind turbines from the most important aspects including structural dynamics, control systems, maintenance, manufacturing and electrical equipment. A case study is presented where three different turbines are compared to each other. Furthermore, a study of blade areas for different turbines is presented. The vertical axis wind turbine appears to be advantageous to the horizontal axis wind turbine in several aspects. (author)

A spinner-integrated wind lidar for enhanced wind turbine control

DEFF Research Database (Denmark)

Mikkelsen, Torben; Angelou, Nikolas; Hansen, Kasper Hjorth

2013-01-01

A field test with a continuous wave wind lidar (ZephIR) installed in the rotating spinner of a wind turbine for unimpeded preview measurements of the upwind approaching wind conditions is described. The experimental setup with the wind lidar on the tip of the rotating spinner of a large 80 m roto...... of the spinner lidar data, is investigated. Finally, the potential for enhancing turbine control and performance based on wind lidar preview measurements in combination with feed-forward enabled turbine controllers is discussed. Copyright © 2012 John Wiley & Sons, Ltd....

Noise from wind turbines

International Nuclear Information System (INIS)

Andersen, B.; Larsen, P.

1993-01-01

Denmark has 3200 wind turbines with an installed maximum capacity of 418MW. The most important Danish research projects into wind turbine noise and the main results are listed. These date from 1983. Two comprehensive studies are currently in progress. The first is an analytical and empirical investigation of aerodynamic noise from wind turbine rotors and has so far dealt mainly with tip noise. The measurement method, using a hard board mounted microphone on the ground near the turbine, is described. Four different tip designs have been tested. Some examples of reference sound power level spectra for three of the designs are presented. During the past two years a computerbased data acquisition system has been used for real-time determination of sound power levels. The second study, which has just commenced, is on annoyance from wind turbine noise. It will include noise measurements, masking calculations and a social survey on the perceived nuisance. (UK)

Wind turbines fundamentals, technologies, application, economics

CERN Document Server

Hau, Erich

2013-01-01

"Wind Turbines" addresses all those professionally involved in research, development, manufacture and operation of wind turbines. It provides a cross-disciplinary overview of modern wind turbine technology and an orientation in the associated technical, economic and environmental fields.  In its revised third edition, special emphasis has been given to the latest trends in wind turbine technology and design, such as gearless drive train concepts, as well as on new fields of application, in particular the offshore utilisation of wind energy. The author has gained experience over decades designing wind energy converters with a major industrial manufacturer and, more recently, in technical consulting and in the planning of large wind park installations, with special attention to economics.

The importance of site selection for setting up a wind turbine

Energy Technology Data Exchange (ETDEWEB)

Raghunandan, A.; Gowda, G.; Pandian, A. [MS RAMAIAH Institute of Technology, Bangalore (India); Ramanan, G. [RV College of Engineering, Bangalore (India)

2012-07-01

A wind energy system transforms the kinetic energy of the wind into mechanical or electrical energy that can be harnessed for practical use. Building a wind turbine is far more than simply a matter of finding a field or mountaintop where the wind is blowing and plopping one down. A great deal of attention should be given to finding the proper site for a wind turbine. The main factor one should consider is the average speed of the wind over an extended time. Estimation of the wind power potential for a site is the most important requirement for selecting a site for the installation of a wind turbine. Also wind turbines should be sited well above trees, buildings, and other obstacles else, the result will be poor energy production and increased wear and tear on the turbine. One way to get rid of this is to place the wind turbine on a tall tower. When selecting a place for setting up a wind turbine, engineers consider factors such as wind hazards, characteristics of the land that affect wind speed, and the effects of one turbine on nearby turbines in wind farms. The other factors that are important for selecting a site for installation of wind turbines are Hill effect, Roughness, or the amount of friction that Earth's surface exerts on wind, Tunnel effect, Turbulence, Variations in wind speed, Wind obstacles and Wind shear. This paper will emphasis on the necessary inspections which are to be done on the site before installing a Wind Turbine. (Author)

Practical experience and economic aspects of small wind turbines

Energy Technology Data Exchange (ETDEWEB)

1984-01-01

Workshop proceedings presented cover operating experience and development of wind turbines installed in the UK by Northern Engineering Industries plc companies, the Howden aerogenerator installed in Orkney, and the commissioning of a vertical-axis generator in a remote location. The National Wind Turbine Test Centre, the Caithness Wind Project, the South of Scotland Electricity Board's activities, economics of small scale wind power and commercialisation are discussed.

Wake losses optimization of offshore wind farms with moveable floating wind turbines

International Nuclear Information System (INIS)

Rodrigues, S.F.; Teixeira Pinto, R.; Soleimanzadeh, M.; Bosman, Peter A.N.; Bauer, P.

2015-01-01

Highlights: • We present a layout optimization framework for wind farms with moveable turbines. • Using moveable wind turbines in optimized layouts maximizes energy production. • Turbine and wind farm designers should cooperate to optimize offshore wind projects. - Abstract: In the future, floating wind turbines could be used to harvest energy in deep offshore areas where higher wind mean speeds are observed. Currently, several floating turbine concepts are being designed and tested in small scale projects; in particular, one concept allows the turbine to move after installation. This article presents a novel layout optimization framework for wind farms composed of moveable floating turbines. The proposed framework uses an evolutionary optimization strategy in a nested configuration which simultaneously optimizes the anchoring locations and the wind turbine position within the mooring lines for each individual wind direction. The results show that maximum energy production is obtained when moveable wind turbines are deployed in an optimized layout. In conclusion, the framework represents a new design optimization tool for future offshore wind farms composed of moveable floating turbines

Canadian Wind Energy Association small wind conference proceedings : small wind policy developments (turbines of 300 kW or less)

International Nuclear Information System (INIS)

2005-01-01

The small wind session at the Canadian Wind Energy Association's (CanWEA) annual conference addressed policies affecting small wind, such as net metering, advanced renewable tariffs and interconnections. It also addressed CanWEA's efforts in promoting small wind turbines, particularly in remote northern communities, small businesses and within the residential sector. Small wind systems are typically installed in remote communities to offset utility supplied electricity at the retail price level. In certain circumstances, small wind and hybrid systems can produce electricity at less than half the cost of traditional electricity sources, which in remote communities is typically diesel generators. Small wind turbines require different materials and technologies than large wind turbines. They also involve different local installation requirements, different by-laws, tax treatment and environmental assessments. Small wind turbines are typically installed for a range of factors, including energy independence, energy price stability and to lower environmental impacts of traditional power generation. The small wind session at the conference featured 14 presentations, of which 4 have been catalogued separately for inclusion in this database. tabs., figs

WindPACT Turbine Design Scaling Studies Technical Area 2: Turbine, Rotor and Blade Logistics; TOPICAL

International Nuclear Information System (INIS)

Smith, K.

2001-01-01

Through the National Renewable Energy Laboratory (NREL), the United States Department of Energy (DOE) implemented the Wind Partnership for Advanced Component Technologies (WindPACT) program. This program will explore advanced technologies that may reduce the cost of energy (COE) from wind turbines. The initial step in the WindPACT program is a series of preliminary scaling studies intended to determine the optimum sizes for future turbines, help define sizing limits for certain critical technologies, and explore the potential for advanced technologies to contribute to reduced COE as turbine scales increase. This report documents the results of Technical Area 2-Turbine Rotor and Blade Logistics. For this report, we investigated the transportation, assembly, and crane logistics and costs associated with installation of a range of multi-megawatt-scale wind turbines. We focused on using currently available equipment, assembly techniques, and transportation system capabilities and limitations to hypothetically transport and install 50 wind turbines at a facility in south-central South Dakota

Wind turbines - facts from 20 years of technological progress

Energy Technology Data Exchange (ETDEWEB)

Hansen, L H; Dannemand Andersen, P [Risoe Ntaional Lab., Roskilde (Denmark)

1999-03-01

The first Danish commercial wind turbines were installed in the late 1970s. Over the last 20 years the Danish wind turbine market has been relatively stable concerning annual installations, and the wind turbine technology has been able to develop continuously. This gives a unique time track for technology analysts. The aim of this paper is to extract reliable information on this time track from existing archives and statistics. Seven generations of wind turbine technology have been identified mainly based on `characteristic` rotor diameters. The technological development of each generation is described using indicators such as: market share in Denmark, generator size, rotor diameter, hub height, electricity production and productivity. Economical indicators comprise: costs of turbine and standard foundation. (au)

Wind turbines - facts from 20 years of technological progress

International Nuclear Information System (INIS)

Hansen, L.H.; Dannemand Andersen, P.

1999-01-01

The first Danish commercial wind turbines were installed in the late 1970s. Over the last 20 years the Danish wind turbine market has been relatively stable concerning annual installations, and the wind turbine technology has been able to develop continuously. This gives a unique time track for technology analysts. The aim of this paper is to extract reliable information on this time track from existing archives and statistics. Seven generations of wind turbine technology have been identified mainly based on 'characteristic' rotor diameters. The technological development of each generation is described using indicators such as: market share in Denmark, generator size, rotor diameter, hub height, electricity production and productivity. Economical indicators comprise: costs of turbine and standard foundation. (au)

Analysis of the Environmental Impact on Remanufacturing Wind Turbines

Science.gov (United States)

Sosa Skrainka, Manuel R.

To deliver clean energy the use of wind turbines is essential. In June 2011 there was an installed wind capacity equivalent to 211,000MW world-wide (WWEA, 2011). By the end of the year 2009 the U.S. had 35,100MW of wind energy installed capacity to generate electricity (AWEA, 2010). This industry has grown in recent years and is expected to grow even more in the future. The environmental impacts that will arise from the increased number of wind turbines and their end-of-life should be addressed, as large amounts of resources will be required to satisfy the current and future market demands for wind turbines. Since future 10MW wind turbines are expected to be as heavy as 1000 tons each, the study of the environmental response of profitable retirement strategies, such as remanufacturing for these machines, must be considered. Because of the increased number of wind turbines and the materials used, this study provides a comparison between the environmental impacts from remanufacturing the components installed inside the nacelle of multi-megawatt wind turbines and wind turbines manufactured using new components. The study methodology is the following: • Describe the life-cycle and the materials and processes employed for the manufacture and remanufacturing for components inside the nacelle. • Identify remanufacturing alternatives for the components inside the nacelle at the end of the expected life-time service of wind turbines. • Evaluate the environmental impacts from the remanufactured components and compare the results with the impacts of the manufacturing of new components using SimaPro. • Conduct sensitivity analysis over the critical parameters of the life cycle assessment • Propose the most environmentally friendly options for the retirement of each major component of wind turbines. After an analysis of the scenarios the goal of the study is to evaluate remanufacturing as an end-of-life option from an environmental perspective for commercial multi

Prototype bucket foundation for wind turbines

DEFF Research Database (Denmark)

Ibsen, Lars Bo; Liingaard, Morten

The first full scale prototype bucket foundation for wind turbines has been installed in October 2002 at Aalborg University offshore test facility in Frederikshavn, Denmark. The suction caisson and the wind turbine have been equipped with an online monitoring system, consisting of 15 accelerometers...... and a real-time data-acquisition system. The report concerns the in service performance of the wind turbine, with focus on estimation of the natural frequencies of the structure/foundation. The natural frequencies are initially estimated by means of experimental Output-only Modal analysis. The experimental...... estimates are then compared with numerical simulations of the suction caisson foundation and the wind turbine. The numerical model consists of a finite element section for the wind turbine tower and nacelle. The soil-structure interaction of the soil-foundation section is modelled by lumped-parameter models...

Utility scale wind turbines on a grid-connected island: A feasibility study

Energy Technology Data Exchange (ETDEWEB)

Dua, Mohit; Manwell, James F.; McGowan, Jon G. [Department of Mechanical and Industrial Engineering, Renewable Energy Research Laboratory (RERL), University of Massachusetts, Amherst, MA 01003 (United States)

2008-04-15

This paper analyzes the technical and economic feasibility of installing utility-scale wind turbines on the Fox Islands, located 12 miles from the coast of Maine in the United States. Three locations on the islands, as well as a near offshore site, are analyzed in detail as potential sites for wind turbine installations. As discussed in this work, the logistic problems of transporting and installing wind turbines on the island require innovative solutions. These include locally available amphibious vessels, which can land turbine components at suitable shallow spots on the island, self-erecting towers, which allow use of a smaller crane for installation, and a special turbine foundation suitable for the local ground conditions. In the economic analysis, in addition to standard life-cycle parameters, renewable energy credits (REC) were also included. This work concludes that the installation of sub-megawatt wind turbines on the island is logistically possible and will lead to a reduction in the cost of electricity to the customers. (author)

Site calibration for the wind turbine performance evaluation

International Nuclear Information System (INIS)

Nam, Yoon Su; Yoo, Neung Soo; Lee, Jung Wan

2004-01-01

The accurate wind speed information at the hub height of a wind turbine is very essential to the exact estimation of the wind turbine power performance testing. Several method on the site calibration, which is a technique to estimate the wind speed at the wind turbine's hub height based on the measured wind data using a reference meteorological mast, are introduced. A site calibration result and the wind resource assessment for the TaeKwanRyung test site are presented using three-month wind data from a reference meteorological mast and the other mast temporarily installed at the site of wind turbine. Besides, an analysis on the uncertainty allocation for the wind speed correction using site calibration is performed

World trend - a 10% growth per year for small wind turbines

International Nuclear Information System (INIS)

Kane, M.

2016-01-01

A decline was expected for small wind turbine business with the advent of bigger wind turbines but it is really not the case. In 2014 the growth rate was about 10 % with a cumulated power installed that year of 830 MW for small wind turbines. China (41% of the installed capacity), United-States (30%) and Great-Britain (15%) are the 3 main players. About 1 million wind turbines are operating in the world - it means 8.3% (∼ 70.000 units) more than a year before. (A.C.)

Small Wind Turbine Applications: Current Practice in Colorado

International Nuclear Information System (INIS)

Green, Jim

1999-01-01

Numerous small wind turbines are being used by homeowners in Colorado. Some of these installations are quite recent while others date back to the federal tax-credit era of the early 1980s. Through visits with small wind turbine owners in Colorado, I have developed case studies of six small wind energy applications focusing on the wind turbine technology, wind turbine siting, the power systems and electric loads, regulatory issues, and motivations about wind energy. These case studies offer a glimpse into the current state-of-the-art of small-scale wind energy and provide some insight into issues affecting development of a wider market

Noise from wind turbines

Energy Technology Data Exchange (ETDEWEB)

Fegeant, Olivier [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Building Sciences

2002-02-01

A rapid growth of installed wind power capacity is expected in the next few years. However, the siting of wind turbines on a large scale raises concerns about their environmental impact, notably with respect to noise. To this end, variable speed wind turbines offer a promising solution for applications in densely populated areas like the European countries, as this design would enable an efficient utilisation of the masking effect due to ambient noise. In rural and recreational areas where wind turbines are sited, the ambient noise originates from the action of wind on the vegetation and about the listener's ear (pseudo-noise). It shows a wind speed dependence similar to that of the noise from a variable speed wind turbine and can therefore mask the latter for a wide range of conditions. However, a problem inherent to the design of these machines is their proclivity to pure tone generation, because of the enhanced difficulty of avoiding structural resonances in the mechanical parts. Pure tones are deemed highly annoying and are severely regulated by most noise policies. In relation to this problem, the vibration transmission of structure-borne sound to the tower of the turbine is investigated, in particular when the tower is stiffened at its upper end. Furthermore, since noise annoyance due to wind turbine is mostly a masking issue, the wind-related sources of ambient noise are studied and their masking potentials assessed. With this aim, prediction models for wind-induced vegetation noise and pseudo-noise have been developed. Finally, closely related to the effect of masking, is the difficulty, regularly encountered by local authorities and wind farm developers, to measure noise immission from wind turbines. A new measurement technique has thus been developed in the course of this work. Through improving the signal-to-noise ratio between wind turbine noise and ambient noise, the new technique yields more accurate measurement results.

Flow separation on wind turbines blades

NARCIS (Netherlands)

Corten, G.P.

2001-01-01

In the year 2000, 15GW of wind power was installed throughout the world, producing 100PJ of energy annually. This contributes to the total electricity demand by only 0.2%. Both the installed power and the generated energy are increasing by 30% per year world-wide. If the airflow over wind turbine

Next Generation Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Cheraghi, S. Hossein [Western New England Univ., Springfield, MA (United States); Madden, Frank [FloDesign Wind Turbine Corp., Waltham, MA (United States)

2012-09-01

The goal of this collaborative effort between Western New England University's College of Engineering and FloDesign Wind Turbine (FDWT) Corporation to wok on a novel areodynamic concept that could potentially lead to the next generation of wind turbines. Analytical studies and early scale model tests of FDWT's Mixer/Ejector Wind Turbine (MEWT) concept, which exploits jet-age advanced fluid dynamics, indicate that the concept has the potential to significantly reduce the cost of electricity over conventional Horizontal Axis Wind Turbines while reducing land usage. This project involved the design, fabrication, and wind tunnel testing of components of MEWT to provide the research and engineering data necessary to validate the design iterations and optimize system performance. Based on these tests, a scale model prototype called Briza was designed, fabricated, installed and tested on a portable tower to investigate and improve the design system in real world conditions. The results of these scale prototype efforts were very promising and have contributed significantly to FDWT's ongoing development of a product scale wind turbine for deployment in multiple locations around the U.S. This research was mutually beneficial to Western New England University, FDWT, and the DOE by utilizing over 30 student interns and a number of faculty in all efforts. It brought real-world wind turbine experience into the classroom to further enhance the Green Engineering Program at WNEU. It also provided on-the-job training to many students, improving their future employment opportunities, while also providing valuable information to further advance FDWT's mixer-ejector wind turbine technology, creating opportunities for future project innovation and job creation.

Site-optimization of wind turbine generators

Energy Technology Data Exchange (ETDEWEB)

Wolff, T.J. de; Thillerup, J. [Nordtank Energy Group, Richmond, VA (United States)

1997-12-31

The Danish Company Nordtank is one of the pioneers within the wind turbine industry. Since 1981 Nordtank has installed worldwide more than 2500 wind turbine generators with a total name plate capacity that is exceeding 450 MW. The opening up of new and widely divergent markets has demanded an extremely flexible approach towards wind turbine construction. The Nordtank product range has expanded considerable in recent years, with the main objective to develop wind energy conversion machines that can run profitable in any given case. This paper will describe site optimization of Nordtank wind turbines. Nordtank has developed a flexible design concept for its WTGs in the 500/750 kW range, in order to offer the optimal WTG solution for any given site and wind regime. Through this flexible design, the 500/750 turbine line can adjust the rotor diameter, tower height and many other components to optimally fit the turbine to each specific project. This design philosophy will be illustrated with some case histories of recently completed projects.

The benefits of geographical dispersion of offshore wind turbines.

NARCIS (Netherlands)

Assen van, Vincent

2012-01-01

Summary Wind energy is one of the possible solutions to minimise the greenhouse gas emissions of our electricity production. Therefore, the Dutch government aims to install 6000 MW of wind turbines on the Dutch North Sea. The power output of wind turbine

Lightning protection of wind turbines

Energy Technology Data Exchange (ETDEWEB)

Soerensen, T; Brask, M H [DEFU (Denmark); Jensen, F V; Raben, N [SEAS (Denmark); Saxov, J [Nordjyllandsvaerket (Denmark); Nielsen, L [Vestkraft (Denmark); Soerensen, P E [Risoe National Lab. (Denmark)

1999-03-01

Lightning damage to wind turbines is a serious problem for Danish power companies, who have experienced some cases with very costly lightning damage and a large number of cases with minor damage. The most costly cases include one catastrophic damage to an entire wind turbine, and several cases of destruction of blades, main bearings, generators and control systems. Over the years there have been several hundreds of cases with minor damage - typically damage and interruptions of the control and communication systems, or the power systems. The Danish power companies anticipate that the lightning threat will be even bigger for the large off-shore wind turbine installations that are currently being planned in Denmark. Furthermore, it is known from the off-shore wind turbines at Vindeby in Denmark that the costs of inspection and particularly repair work must be expected to be much higher off-shore as compared to wind turbines on land. These considerations was the background for a two year project concerned with investigation of lighting damages and with the formulation of a DEFU Recommendation for lightning protection of wind turbines, which was published in January 1999. The project was funded by the Danish power companies Elsam, Eltra, Elkraft and by DEFU. (au)

Experiences and results from Elkraft 1 MW wind turbine

Energy Technology Data Exchange (ETDEWEB)

Raben, N; Jensen, F V [SEAS Distribution A.m.b.A., Wind Power Dept., Haslev (Denmark); Oeye, S [DTU, Inst. for Energiteknik, Lyngby (Denmark); Markkilde Petersen, S; Antoniou, I [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

1999-03-01

The Elkraft 1 MW Demonstration wind turbine was at the time of installation in 1993 the largest stall controlled wind turbine in the world. It was constructed to allow accurate comparison of two different forms of operation: pitch control and stall control. A comprehensive programme for the investigation of the two operation modes was established. This paper presents the main experiences from five years of operation and measurements. For a three-year period the wind turbine was in operation in stall controlled mode. During this period the turbine faced problems of various significance. Especially lightning strikes and unusually poor wind conditions caused delays of the project. In early 1997, the wind turbine was modified to enable pitch controlled operation. The gearbox ratio was changed in order to allow higher rotor speed, the hydraulic system was altered and new control software was installed. Tests were carried out successfully during the spring of 1997 and the wind turbine has since been operating as a pitch controlled wind turbine. The most significant events and problems are presented and commented in this paper along with results from the measurement programme. The results cover both stall and pitch controlled operation and include power curves, annual energy production, structural loads, fatigue loads etc. (au) 10 refs.

Wind-power installation on the Guetsch in Switzerland; Windkraftanlage Guetsch, EW Ursern, Andermatt UR

Energy Technology Data Exchange (ETDEWEB)

Russi, M.

2006-07-01

This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at the 800 kW wind turbine installed in 2001/2002 by the Ursern electricity utility near Andermatt, Switzerland, at a height of 2350 meters above sea level. The original prototype wind turbine contained various components from Swiss industry, such as the generator and the inverter. Because of difficulties (cracks in rotor blades, bankruptcy of the manufacturer, etc.) this installation was replaced by an Enercon 600-kW-wind turbine in 2004. Characteristic features of this turbine, such as is its adaptation for use under turbulent wind conditions at cold locations, are discussed. The results obtained in 2005 made it obvious that the utilisation of wind energy in alpine regions is possible and that the extreme conditions at this location do not significantly affect the efficient and safe operation of such an installation. Together with the presence of a meteorological station in the vicinity, optimal operating conditions prevail at this site for further research projects in connection with icing-up of turbine blades and wind energy. The report describes the installation and de-installation of the first turbine and the installation of the present one. Initial experience gained with the installation and its certification by the 'Naturemade' eco-power programme is discussed, as is future expansion at the site.

Wind power integration : From individual wind turbine to wind park as a power plant

NARCIS (Netherlands)

Zhou, Y.

2009-01-01

As power capacities of single wind turbine, single wind park and total wind power installation are continuously increasing, the wind power begins to challenge the safety operation of the power system. This thesis focuses on the grid integration aspects such as the dynamic behaviours of wind power

Economic feasibility of developing wind turbines in Aligoodarz, Iran

International Nuclear Information System (INIS)

Mohammadi, Kasra; Mostafaeipour, Ali

2013-01-01

Highlights: • Three hourly long term measured wind speed data from 2005 to 2009 for city of Aligoodarz in Iran was analyzed. • Wind power density and wind energy density of the region were estimated using Weibull distribution. • Performance of six different wind turbine models were analyzed. • Economic evaluation was performed and installing of E-3120 (50 kW) model turbine was suggested. - Abstract: This study evaluates the economic feasibility of electricity generation using wind turbines in city of Aligoodarz situated in the west part of Iran. For this purpose, the wind energy potential and its characteristics were assessed in terms of diurnal, monthly and annual analysis using five years measured wind speed data from 2005 to 2009 at 10 m height. The analysis results specified a nearly stable wind pattern in different hours and months of the year which demonstrated more suitability of the region for wind energy harnessing to meet the electricity demand in all time intervals throughout the year. According to Pacific Northwest Laboratory (PNL) wind power classification, the wind resource in Aligoodarz falls in class 3 and the location was recognized as a moderate location for wind energy development. The economic feasibility of six different wind turbines with rated powers ranging from 20 to 150 kW was evaluated. Among all turbines examined, the E-3120 wind turbine was introduced as the most attractive option for installation

Improved Formulation for the Optimization of Wind Turbine Placement in a Wind Farm

Directory of Open Access Journals (Sweden)

Zong Woo Geem

2013-01-01

Full Text Available As an alternative to fossil fuels, wind can be considered because it is a renewable and greenhouse gas-free natural resource. When wind power is generated by wind turbines in a wind farm, the optimal placement of turbines is critical because different layouts produce different efficiencies. The objective of the wind turbine placement problem is to maximize the generated power while minimizing the cost in installing the turbines. This study proposes an efficient optimization formulation for the optimal layout of wind turbine placements under the resources (e.g., number of turbines or budget limit by introducing corresponding constraints. The proposed formulation gave users more conveniences in considering resources and budget bounds. After performing the optimization, results were compared using two different methods (branch and bound method and genetic algorithm and two different objective functions.

Scour around Offshore Wind Turbine Foundations

DEFF Research Database (Denmark)

Petersen, Thor Ugelvig

Over the last decades several offshore wind farms have been installed and commissioned in the European waters. Typically the foundations of the wind turbines are protected against scour at the base by installing scour protection with rock dump. The Egmond aan Zee offshore wind farm located about 10...... the performance (stability) of the scour protection and to quantify the edge scour development at the circumference of the scour protection. The survey campaign showed considerable edge scour of up to 2.7 m, which was expected from design considerations. However, no clear information exists on the mechanisms...... causing the edge scour development around scour protections at offshore wind turbine foundations. The purpose of the present thesis is to investigate and explain the development of the edge scour in such applications, and describe the flow mechanism causing the scour. Furthermore, the dissertation also...

Effects of Icing on Wind Turbine Fatigue Loads

International Nuclear Information System (INIS)

Frohboese, Peter; Anders, Andreas

2007-01-01

The external conditions occurring at cold climate sites will affect wind turbines in different ways. The effects of ice accretion on wind turbines and the influence on the turbine fatigue loads are examined. The amount of icing prior to turbine installation needs to be estimated by using standard measurement data and considering the geometry of the proposed turbine. A procedure to calculate the expected ice accretion on wind turbines out of standard measurement data is explained and the results are discussed. Different parameters to describe the accreted ice on the turbine are examined separately in a fatigue load calculation. The results of the fatigue load calculation are discussed and selected cases are presented

Transient power coefficients for a two-blade Savonius wind turbine

Energy Technology Data Exchange (ETDEWEB)

Pope, K.; Naterer, G. [Univ. of Ontario Inst. of Technology, Oshawa, ON (Canada). Faculty of Engineering and Applied Science

2010-07-01

The wind power industry had a 29 percent growth rate in installed capacity in 2008, and technological advances are helping to speed up growth by significantly increasing wind turbine power yields. While the majority of the industry's growth has come from large horizontal axis wind turbine installations, small wind turbines can also be used in a wide variety of applications. This study predicted the transient power coefficient for a Savonius vertical axis wind turbine (VAWT) wind turbine with 2 blades. The turbine's flow field was used to analyze pressure distribution along the rotor blades in relation to the momentum, lift, and drag forces on the rotor surfaces. The integral force balance was used to predict the transient torque and power output of the turbine. The study examined the implications of the addition of a second blade on the model's ability to predict transient power outputs. Computational fluid dynamics (CFD) programs were used to verify that the formulation can be used to accurately predict the transient power coefficients of VAWTs with Savonius blades. 11 refs., 1 tab., 6 figs.

Wind turbine blade waste in 2050.

Science.gov (United States)

Liu, Pu; Barlow, Claire Y

2017-04-01

Wind energy has developed rapidly over the last two decades to become one of the most promising and economically viable sources of renewable energy. Although wind energy is claimed to provide clean renewable energy without any emissions during operation, but it is only one side of the coin. The blades, one of the most important components in the wind turbines, made with composite, are currently regarded as unrecyclable. With the first wave of early commercial wind turbine installations now approaching their end of life, the problem of blade disposal is just beginning to emerge as a significant factor for the future. This paper is aimed at discovering the magnitude of the wind turbine blade waste problem, looking not only at disposal but at all stages of a blade's lifecycle. The first stage of the research, the subject of this paper, is to accurately estimate present and future wind turbine blade waste inventory using the most recent and most accurate data available. The result will provide a solid reference point to help the industry and policy makers to understand the size of potential environmental problem and to help to manage it better. This study starts by estimating the annual blade material usage with wind energy installed capacity and average blade weight. The effect of other waste contributing factors in the full lifecycle of wind turbine blades is then included, using industrial data from the manufacturing, testing and in-service stages. The research indicates that there will be 43 million tonnes of blade waste worldwide by 2050 with China possessing 40% of the waste, Europe 25%, the United States 16% and the rest of the world 19%. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Optimal Risk-Based Inspection Planning for Offshore Wind Turbines

DEFF Research Database (Denmark)

Rangel-Ramirez, Jose G.; Sørensen, John Dalsgaard

2008-01-01

, inspection and maintenance activities are developed. This paper considers aspects of inspection and maintenance planning of fatigue prone details in jacket and tripod types of wind turbine support structures. Based oil risk-based inspection planning methods used for oil & gas installations, a framework......Wind turbines for electricity production have increased significantly the last years both in production capability and size. This development is expected to continue also in the coining years. The Support structure for offshore wind turbines is typically a steel structure consisting of a tower...... for optimal inspection and maintenance planning of offshore wind turbines is presented. Special aspects for offshore wind turbines are considered: usually the wind loading are dominating the wave loading, wake effects in wind farms are important and the reliability level is typically significantly lower than...

Potentials for site-specific design of MW sized wind turbines

DEFF Research Database (Denmark)

Thomsen, K.; Fuglsang, P.; Schepers, G.

2001-01-01

The potential for site specific design of MW sized wind turbines is quantified by comparing design loads for wind turbines installed at a range of different sites. The sites comprise on-shore normal flat terrain stand-alone conditions and wind farm conditions together with offshore and mountainous...

Feasibility of generating electricity for clinics using wind turbines

CSIR Research Space (South Africa)

Szewczuk, S

2015-08-01

Full Text Available is small wind turbines used in residential settings that are installed using net metering to supply energy directly to the home. Excess energy is sold back to the supplying utility. Farm, business and small industrial wind applications are used..., businesses are not eligible for net metering applications thus the commercial loads must use most of the power from the turbine. “Small-scale” community wind is a system using wind turbines to power grid-connected loads such as schools, public lighting...

Siting guidelines for utility application of wind turbines. Final report

Energy Technology Data Exchange (ETDEWEB)

Pennell, W.T.

1983-01-01

Utility-oriented guidelines are described for identifying viable sites for wind turbines. Topics and procedures are also discussed that are important in carrying out a wind turbine siting program. These topics include: a description of the Department of Energy wind resource atlases; procedures for predicting wind turbine performance at potential sites; methods for analyzing wind turbine economics; procedures for estimating installation and maintenance costs; methods for anlayzing the distribution of wind resources over an area; and instrumentation for documenting wind behavior at potential sites. The procedure described is applicable to small and large utilities. Although the procedure was developed as a site-selection tool, it can also be used by a utility who wishes to estimate the potential for wind turbine penetration into its future generation mix.

Condition analysis and operating lifetime extension concepts for wind turbines

Energy Technology Data Exchange (ETDEWEB)

Korzeniewski, Thomas [GMA-Engineering GmbH, Hamburg (Germany). Business Unit Wind Energy

2014-11-01

In Germany the basis for the expansion of wind energy was already laid at the beginning of the 1990s. Hence, the first wind turbines already started to reach the end of their permitted lifetime. At that time as today the different wind turbine types were engineered for an operational lifetime of 20 years. As reliable wind turbines types were already available in the 1990s, it is technically and commercially reasonable to consider the extension of their operational lifetime. Of particular interest is the lifetime extension of wind turbine types installed in the beginning of the 2000s. During that period many wind turbine types were launched which absolutely correspond to state-of-the-art technology.

Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint

Energy Technology Data Exchange (ETDEWEB)

Wayman, E. N.; Sclavounos, P. D.; Butterfield, S.; Jonkman, J.; Musial, W.

2006-03-01

the two concepts was also performed. Key cost components included the material and construction costs of the buoy; material and installation costs of the tethers, mooring lines, and anchor technologies; costs of transporting and installing the system at the chosen site; and the cost of mounting the wind turbine to the platform. The two systems were evaluated based on their static and dynamic performance and the total system installed cost. Both systems demonstrated acceptable motions, and have estimated costs of $1.4-$1.8 million, not including the cost of the wind turbine, the power electronics, or the electrical transmission.

Future on Power Electronics for Wind Turbine Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Ma, Ke

2013-01-01

networks and more and more wind power stations, acting as power plants, are connected directly to the transmission networks. As the grid penetration and power level of the wind turbines increase steadily, the wind power starts to have significant impacts to the power grid system. Therefore, more advanced...... generators, power electronic systems, and control solutions have to be introduced to improve the characteristics of the wind power plant and make it more suitable to be integrated into the power grid. Meanwhile, there are also some emerging technology challenges, which need to be further clarified......Wind power is still the most promising renewable energy in the year of 2013. The wind turbine system (WTS) started with a few tens of kilowatt power in the 1980s. Now, multimegawatt wind turbines are widely installed even up to 6-8 MW. There is a widespread use of wind turbines in the distribution...

Lightning protection for wind turbines in Vietnam

Directory of Open Access Journals (Sweden)

Thuan Nguyen

2017-01-01

Full Text Available Wind energy has become increasingly important in the total electrical energy supply mix in Vietnam over the last few years. Small, kW turbines were installed in isolated areas a decade ago, while wind farms of several MW to few hundred MW are now being connected directly to national grid, with many additional projects in planning or under construction to fulfill an objective of 6% of the total installed capacity by 2030 (approximately 6200 MW of wind energy component. The increase in wind farm generation results in increased damage from lightning. In this paper, the annual frequency of lightning strikes to wind turbines in Vietnam is calculated using electrogeometric model. Reported lightning incidents to three major wind farms in Vietnam are summarized. Possible causes of failure are discussed, and an EMTP simulation for each incident was performed accordingly. The simulations suggest the failure mechanisms as well the potential of improved grounding to reduce lightning induced damage in future windfarms.

Investigation of the interactions between wind turbines and radio systems aimed at establishing co-siting guidelines. Phase 1: Introduction and modelling of wind turbine scatter, appendices E, F and G

International Nuclear Information System (INIS)

Dabis, H.S.; Chignell, R.J.

1997-01-01

The potential for wind turbines to interfere with radio systems can be a source of conflict between radio operators and the wind energy community. In this report, the problem of accurately predicting the effects of wind turbines on radio systems with the aim of establishing guidelines for their installation is investigated. Initially models for the scatter mechanisms that occur at the wind turbine are developed. These models predict the wind turbine radar cross section and the modulation effects due to the rotation of the blades. Initial validation of these models is established by comparing the predicted results with a set of measurements obtained from experiments performed on a 20:1 scale model wind turbine. It is shown that generally these results agree well. These results are then used in the guideline formulation to compute, for specific radio systems, regions where wind turbines cannot be installed. Examples using realistic parameters for various radio systems are presented. Further validation of the derived models is required. (author)

Design optimization and analysis of vertical axis wind turbine blade

International Nuclear Information System (INIS)

Jarral, A.; Ali, M.; Sahir, M.H.

2013-01-01

Wind energy is clean and renwable source of energy and is also the world's fastest growing energy resource. Keeping in view power shortages and growing cost of energy, the low cost wind energy has become a primary solution. It is imperative that economies and individuals begin to conserve energy and focus on the production of energy from renewable sources. Present study describes a wind turbine blade designed with enhanced aerodynamic properties. Vertical axis turbine is chosen because of its easy installment, less noisy and having environmental friendly characteristics. Vertical axis wind turbines are thought to be ideal for installations where wind conditions are not consistent. The presented turbine blade is best suitable for roadsides where the rated speed due to vehicles is most /sup -1/ often 8 ms .To get an optimal shape design symmetrical profile NACA0025 has been considered which is then analyzed for stability and aerodynamic characteristics at optimal conditions using analysis tools ANSYS and CFD tools. (author)

Rule - based Fault Diagnosis Expert System for Wind Turbine

Directory of Open Access Journals (Sweden)

Deng Xiao-Wen

2017-01-01

Full Text Available Under the trend of increasing installed capacity of wind power, the intelligent fault diagnosis of wind turbine is of great significance to the safe and efficient operation of wind farms. Based on the knowledge of fault diagnosis of wind turbines, this paper builds expert system diagnostic knowledge base by using confidence production rules and expert system self-learning method. In Visual Studio 2013 platform, C # language is selected and ADO.NET technology is used to access the database. Development of Fault Diagnosis Expert System for Wind Turbine. The purpose of this paper is to realize on-line diagnosis of wind turbine fault through human-computer interaction, and to improve the diagnostic capability of the system through the continuous improvement of the knowledge base.

Design of a New Foundation for Offshore Wind Turbines

DEFF Research Database (Denmark)

Ibsen, Lars Bo; Brincker, Rune

2004-01-01

was installed at the test field in Frederikshavn in late 2003, with a 3 MW wind turbine in normal operation. The R&D work is continued the complete the bucket concept and having the design standards for the construction and installation methodologies recognised. The design saves about half of the steel weight...... as compared to a traditional pile foundation, it is much easier to install and it can easily be removed when the wind turbine is taken down. However, the new design is suffering from uncertainties in the accumulated fatigue in the both the steel structure and the surrounding earth material. Therefore an on......The gravitation platform and the monopile have in the previous major offshore wind turbine projects been dominating. A four-year research and development project has proven the bucket foundation to be feasible in suitable soil condition in water depth from near shore to app. 40 meters. A prototype...

Review of contemporary wind turbine concepts and their market

International Nuclear Information System (INIS)

Hansen, Anca D.; Iov, Florin; Blaabjerg, Frede; Hansen, Lars H.

2004-01-01

The main aim of this paper is to investigate the market penetration and share of different wind turbine concepts during the years 1998-2002, a period when the increase in the wind power capacity is starting to mark an abrupt evolution (more than two GW per year). A detailed overview is performed based on suppliers market data and concept evaluation for each individual wind turbine type sold by the Top Ten suppliers over the selected five years. The investigation is processing information on a total number of approximately 90 wind turbine types from 13 different manufacturers, which have been on the Top Ten list of wind turbine suppliers during 1998 to 2002. The analysis is based on very comprehensive data, which cover approximately 76% of the accumulated world wind power installed at the end of 2002. The paper also provides an overall perspective on the contemporary wind turbine concepts, classified with respect to both their speed control ability and to their power control type. Trends for wind turbine concepts are discussed. (Author)

Byers Auto Group: A Case Study Into The Economics, Zoning, and Overall Process of Installing Small Wind Turbines at Two Automotive Dealerships in Ohio

Energy Technology Data Exchange (ETDEWEB)

Oteri, F.; Sinclair, K.

2011-11-01

This paper provides the talking points about a case study on the installation of a $600,000 small wind project, the installation process, estimated annual energy production and percentage of energy needs met by the turbines.

Recommendation for an European wind turbine safety standard

Energy Technology Data Exchange (ETDEWEB)

Hjuler Jensen, P.; Hauge Madsen, P.; Winther-Jensen, M.; Machielse, L.; Stam, W.; Einsfeld, V.; Woelfel, E.; Elliot, G.; Wilde, L. de

1988-09-15

The objective is to establish an European standard for wind safety which should apply for all member countries of the European Communities. The document contains a list of recommended safety requirements in relation to the system, structure, electrical installations, operation and maintenance of wind turbines. The recommended safety standards cover electricity producing wind turbines connected to electricity grids in both single and cluster applications and with a swept area in excess of 25 square meters and/or a rated power of 10kW. The document should be used in combination with The European Standards for Wind Turbine Loads and other relevant European Standards. Environmental condition, with the emphasis of wind conditions and more extreme climatic conditions, are also considered in relation to safety requirements. (AB).

Applications of wind turbines in Canada

Energy Technology Data Exchange (ETDEWEB)

South, P; Rangi, R S; Templin, R J

1977-01-01

There are differing views as to the role of wind energy in the overall requirements. While some people tend to ignore it there are others who think that wind could be a major source of energy. In this paper an effort has been made to determine the wind power potential and also the amount that is economically usable. From the existing wind data a map showing the distribution of wind power density has been prepared. This map shows that the maritime provinces and the west coast of Hudson Bay have high wind power potential. These figures show that the wind power potential is of the same order as the installed electrical generating capacity in Canada (58 x 10/sup 6/kW in 1974). However, in order to determine how much of this power is usable the economics of adding wind energy to an existing system must be considered. A computer program has been developed at NRC to analyze the coupling of wind turbines with mixed power systems. Using this program and making certain assumptions about the cost of WECS and fuel the maximum amount of usable wind energy has been calculated. It is shown that if an installed capacity of 420 megawatts of wind power was added to the existing diesel capacity it would result in a savings of 60,000,000 gallons of fuel oil per year. On the other hand it is shown that if the existing installed hydro electric capacity of 37,000 megawatts (1976) was increased to 60,000 megawatts without increasing the average water flow rate, an installed capacity of 60,000 megawatts of wind power could be added to the system. This would result in an average of 14,000 megawatts from the wind. Using projected manufacturing costs for vertical axis wind turbines, the average cost of wind energy could be in the range of 1.4 cents/kwh to 3.6 cents/kwh.

Lighter-than-air wind turbines in remote communities

Energy Technology Data Exchange (ETDEWEB)

Wilkins, M.; Ferguson, F.; Akhiwu, K. [Magenn Power Inc., Ottawa, ON (Canada)

2008-07-01

This paper presented the 100 kW Magenn Air Rotor System (MARS) drag-type wind turbine system that is based on lighter-than-air technology. It consists of an axisymmetric helium-filled core balloon, anchored to the ground via a tether containing high-tenacity fibers as well as copper conductors. The torque for the rotation is provided by sails fixed to the surface of the balloon. A winch on the ground allows the tether to be reeled in and out up to a height of 300 m. The feasibility of using the system in 2 specific local community-owned power network was investigated. The results of initial testing were discussed. Highly consistent winds at 300 m altitude were found to result in power densities 3 to 4 times what is available to a conventional 100 kW wind turbine. The inflatable structures reduce capital costs as well as equipment and shipping costs associated with installation in remote areas. It was concluded that the MARS system is very simple to install and despite its large size, no cranes or oversized vehicles are needed to deploy the system. The high-altitude wind power using tethered wind turbine devices has the potential to open up new wind resources in areas that are not served by conventional turbines. 6 refs., 3 tabs., 2 figs.

Wind turbine concept market penetration over 10 years (1995-2004)

International Nuclear Information System (INIS)

Hansen, Anca D.; Hansen, Lars H.

2006-01-01

The aim of this article is to investigate the market penetration and share of different wind turbine concepts during the years 1995-2004, a period that represents the maturational era of the modern wind power industry. A detailed overview is given based on suppliers' market data and concept evaluation for each individual wind turbine type sold by the Top Ten suppliers over the selected decade. The investigation is processing information on approximately 160 wind turbine types from 22 different manufacturers that have featured in the Top Ten list of wind turbine suppliers during 1995-2004. The analysis is based on comprehensive data covering approximately 97% of the cumulative wind power installed worldwide at the end of 2004. The article also provides an overall perspective on contemporary wind turbine concepts, classified with respect to both their speed control ability and power control type. Current and future trends for wind turbine concepts are discussed. (Author)

Risk assessment of wind turbines close to highways

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Sørensen, Jens Nørkær; Lemming, Jørgen Kjærgaard

2012-01-01

with a spacing of 400m. As an example the generally accepted risk on highways in increased with less than 0.1% in wind turbines are installed more than 150 meters from the highway. The risk due to ice throw from a wind turbine in operation is seen to be slightly greater than the risk if the wind turbine......) and a spacing of 400-500 m along the road. The studies show that the probability per kilometer that a person in a vehicle is killed due to total or partial collapse (damage) of a wind turbine can be assumed to be of minor importance. The probability per kilometer will be less than 5 10-12 for wind turbines...... that are more than 60 meters from the road. This risk is considered acceptable using the ALARP principle and comparing with the general, well-documented risk on roads in Denmark which in 2009 was 2 10-9. The analysis also shows that the height of the turbines and the distance between them is of less importance...

A wind turbine evaluation model under a multi-criteria decision making environment

International Nuclear Information System (INIS)

Lee, Amy H.I.; Hung, Meng-Chan; Kang, He-Yau; Pearn, W.L.

2012-01-01

Highlights: ► This paper proposes an evaluation model to select suitable turbines in a wind farm. ► Interpretive structural modeling is used to know the relationship among factors. ► Fuzzy analytic network process is used to calculate the priorities of turbines. ► The results can be references for selecting the most appropriate wind turbines. - Abstract: Due to the impacts of fossil and nuclear energy on the security, economics, and environment in the world, the demand of alternative energy resources is expanding consistently and tremendously in recent years. Wind energy production, with its safe and environmental characteristics, has become the fastest growing renewable energy source in the world. The construction of new wind farms and the installation of new wind turbines are important processes in order to provide a long-term energy production. In this research, a comprehensive evaluation model, which incorporates interpretive structural modeling (ISM) and fuzzy analytic network process (FANP), is constructed to select suitable turbines when developing a wind farm. A case study is carried out in Taiwan in evaluating the expected performance of several potential types of wind turbines, and experts in a wind farm are invited to contribute their expertise in determining the importance of the factors of the wind turbine evaluation and in rating the performance of the turbines with respect to each factor. The most suitable turbines for installation can finally be generated after the calculations. The results can be references for decision makers in selecting the most appropriate wind turbines.

Simulation and verification of transient events in large wind power installations

Energy Technology Data Exchange (ETDEWEB)

Soerensen, P.; Hansen, A.D.; Christensen, P.; Meritz, M.; Bech, J.; Bak-Jensen, B.; Nielsen, H.

2003-10-01

Models for wind power installations excited by transient events have been developed and verified. A number of cases have been investigated, including comparisons of simulations of a three-phase short circuit, validation with measurements of tripping of single wind turbine, islanding of a group of two wind turbines, and voltage steps caused by tripping of wind turbines and by manual transformer tap-changing. A Benchmark model is also presented, enabling the reader to test own simulation results against results obtained with models developed in EMTDC and DIgSILENT. (au)

IMIS: Integrated Marine Installation System for offshore turbines

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The report describes a feasibility study on the Integrated Marine Installation System for offshore wind turbines. The aspects covered are (1) Background and why the study is required; (2) Aims and objectives of the project; (3) Summary of methods adopted; (4) Design criteria according to the area for deployment; (5) Conclusions and recommendations. The ultimate goal will be to install and secure the wind turbine in position using an integrated approach to avoid using lifting vessels. To date, an initial feasibility study has been carried out where four different concepts were considered. The next phase of the project will be to address a number of possible risks and constraints before the chosen concept can be demonstrated to be viable. The work is being carried out by Setech Ltd, Armstrong Technology Associates Ltd and Smith Rea Energy Ltd for the DTI.

Inverse load calculation procedure for offshore wind turbines and application to a 5-MW wind turbine support structure: Inverse load calculation procedure for offshore wind turbines

Energy Technology Data Exchange (ETDEWEB)

Pahn, T. [Pahn Ingenieure, Am Seegraben 17b 03051 Cottbus Germany; Rolfes, R. [Institut f?r Statik und Dynamik, Leibniz Universit?t Hannover, Appelstra?e 9A 30167 Hannover Germany; Jonkman, J. [National Renewable Energy Laboratory, 15013 Denver West Parkway Golden Colorado 80401 USA

2017-02-20

A significant number of wind turbines installed today have reached their designed service life of 20 years, and the number will rise continuously. Most of these turbines promise a more economical performance if they operate for more than 20 years. To assess a continued operation, we have to analyze the load-bearing capacity of the support structure with respect to site-specific conditions. Such an analysis requires the comparison of the loads used for the design of the support structure with the actual loads experienced. This publication presents the application of a so-called inverse load calculation to a 5-MW wind turbine support structure. The inverse load calculation determines external loads derived from a mechanical description of the support structure and from measured structural responses. Using numerical simulations with the software fast, we investigated the influence of wind-turbine-specific effects such as the wind turbine control or the dynamic interaction between the loads and the support structure to the presented inverse load calculation procedure. fast is used to study the inverse calculation of simultaneously acting wind and wave loads, which has not been carried out until now. Furthermore, the application of the inverse load calculation procedure to a real 5-MW wind turbine support structure is demonstrated. In terms of this practical application, setting up the mechanical system for the support structure using measurement data is discussed. The paper presents results for defined load cases and assesses the accuracy of the inversely derived dynamic loads for both the simulations and the practical application.

Small wind turbine purchasing guide : off-grid, residential, farm and small business applications

International Nuclear Information System (INIS)

2008-11-01

Consumer interest in the environment and the economic advantages of using wind power are now driving interest in smaller wind turbines that range from micro battery-charging models to 300 kW tower-mounted turbines. Smaller turbines are also becoming increasingly accessible through major retail outlets. This guide discussed basic issues surrounding the purchasing, selection and installation of smaller wind turbines. Guidance related to site selection, permitting and approvals was provided, as well as recommendations related to maintenance and system performance. Information related to compliance, safety and setback and zoning restrictions was also presented. The guide was divided into 5 chapters: (1) an introduction to small wind turbines, (2) assessing site-specific expectations, (3) purchasing and permitting, (4) installation, operation and maintenance, and (6) a permitting checklist for small wind customers. Financial incentives for defraying the capital costs of small wind turbines were discussed, and guidance for determining electrical requirements was also provided. A glossary was included, as well as a list of local wind energy contractor and dealers. 3 tabs., 10 figs

Wind turbine reliability : a database and analysis approach.

Energy Technology Data Exchange (ETDEWEB)

Linsday, James (ARES Corporation); Briand, Daniel; Hill, Roger Ray; Stinebaugh, Jennifer A.; Benjamin, Allan S. (ARES Corporation)

2008-02-01

The US wind Industry has experienced remarkable growth since the turn of the century. At the same time, the physical size and electrical generation capabilities of wind turbines has also experienced remarkable growth. As the market continues to expand, and as wind generation continues to gain a significant share of the generation portfolio, the reliability of wind turbine technology becomes increasingly important. This report addresses how operations and maintenance costs are related to unreliability - that is the failures experienced by systems and components. Reliability tools are demonstrated, data needed to understand and catalog failure events is described, and practical wind turbine reliability models are illustrated, including preliminary results. This report also presents a continuing process of how to proceed with controlling industry requirements, needs, and expectations related to Reliability, Availability, Maintainability, and Safety. A simply stated goal of this process is to better understand and to improve the operable reliability of wind turbine installations.

Wind turbines, is it just wind?

International Nuclear Information System (INIS)

Boiteux, M.

2012-01-01

The author first outlines that wind energy is not only random, but almost absent in extreme situations when it would be needed (for example and notably, very cold weather without wind). He suggests the association of a gas turbine to each wind turbine, so that the gas turbine will replace non operating wind turbines. He notices that wind turbines are not proximity energy as they were said to be, and that profitability in fact requires tens of grouped giant wind turbines. He also outlines the high cost of construction of grids for the connection of these wind turbines. Thus, he states that wind energy is far from being profitable in the present conditions of electricity tariffs in France

Power Electronics Converters for Wind Turbine Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Liserre, Marco; Ma, Ke

2012-01-01

The steady growth of installed wind power together with the upscaling of the single wind turbine power capability has pushed the research and development of power converters toward full-scale power conversion, lowered cost pr kW, increased power density, and also the need for higher reliability. ...

CSA guide to Canadian wind turbine codes and standards

International Nuclear Information System (INIS)

2008-01-01

The Canadian wind energy sector has become one of the fastest-growing wind energy markets in the world. Growth of the industry has been supported by various government agencies. However, many projects have experienced cost over-runs or cancellations as a result of unclear regulatory requirements, and wind energy developers are currently subject to a variety of approval processes involving several different authorities. This Canadian Standards Association (CSA) guide provided general information on codes and standards related to the design, approval, installation, operation, and maintenance of wind turbines in Canada. CSA codes and standards were developed by considering 5 new standards adopted by the International Electrotechnical Commission (IEC) Technical Committee on Wind Turbines. The standards described in this document related to acoustic noise measurement techniques; power performance measurements of electricity-producing wind turbines; lightning protection for wind turbine generator systems; design requirements for turbines; and design requirements for small wind turbines. The guide addressed specific subject areas related to the development of wind energy projects that involve formal or regulatory approval processes. Subject areas included issues related to safety, environmental design considerations, site selection, and mechanical systems. Information on associated standards and codes was also included

Damping of wind turbine tower vibrations

DEFF Research Database (Denmark)

Brodersen, Mark Laier; Pedersen, Mikkel Melters

Damping of wind turbine vibrations by supplemental dampers is a key ingredient for the continuous use of monopiles as support for offshore wind turbines. The present thesis consists of an extended summary with four parts and appended papers [P1-P4] concerning novel strategies for damping of tower...... dominated vibrations.The first part of the thesis presents the theoretical framework for implementation of supplemental dampers in wind turbines. It is demonstrated that the feasibility of installing dampers at the bottom of the tower is significantly increased when placing passive or semiactive dampers...... in a stroke amplifying brace, which amplifies the displacement across the damper and thus reduces the desired level of damper force. For optimal damping of the two lowest tower modes, a novel toggle-brace concept for amplifying the bending deformation of the tower is presented. Numerical examples illustrate...

Prototype bucket foundation for wind turbines - natural frequency estimation

Energy Technology Data Exchange (ETDEWEB)

Ibsen, Lars Bo; Liingaard, M.

2006-12-15

The first full scale prototype bucket foundation for wind turbines has been installed in October 2002 at Aalborg University offshore test facility in Frederikshavn, Denmark. The suction caisson and the wind turbine have been equipped with an online monitoring system, consisting of 15 accelerometers and a real-time data-acquisition system. The report concerns the in service performance of the wind turbine, with focus on estimation of the natural frequencies of the structure/foundation. The natural frequencies are initially estimated by means of experimental Output-only Modal analysis. The experimental estimates are then compared with numerical simulations of the suction caisson foundation and the wind turbine. The numerical model consists of a finite element section for the wind turbine tower and nacelle. The soil-structure interaction of the soil-foundation section is modelled by lumped-parameter models capable of simulating dynamic frequency dependent behaviour of the structure-foundation system. (au)

Optimal Wind Turbines Micrositing in Onshore Wind Farms Using Fuzzy Genetic Algorithm

Directory of Open Access Journals (Sweden)

Jun Yang

2015-01-01

Full Text Available With the fast growth in the number and size of installed wind farms (WFs around the world, optimal wind turbines (WTs micrositing has become a challenge from both technological and mathematical points of view. An appropriate layout of wind turbines is crucial to obtain adequate performance with respect to the development and operation of the wind power plant during its life span. This work presents a fuzzy genetic algorithm (FGA for maximizing the economic profitability of the project. The algorithm considers a new WF model including several important factors to the design of the layout. The model consists of wake loss, terrain effect, and economic benefits, which can be calculated by locations of wind turbines. The results demonstrate that the algorithm performs better than genetic algorithm, in terms of maximum values of net annual value of wind power plants and computational burden.

A Method for Modeling of Floating Vertical Axis Wind Turbine

DEFF Research Database (Denmark)

Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir

2013-01-01

It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine....... This integrated dynamic model takes into account the wind inflow, aerodynamics, hydrodynamics, structural dynamics (wind turbine, floating platform and the mooring lines) and a generator control. This approach calculates dynamic equilibrium at each time step and takes account of the interaction between the rotor...

Power electronics converters for wind turbine systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Liserre, Marco; Ma, Ke

2011-01-01

The steady growth of installed wind power which reached 200 GW capacity in 2010, together with the up-scaling of the single wind turbine power capability - 7 MW’s has been announced by manufacturers - has pushed the research and development of power converters towards full scale power conversion,...

Wind turbines and bats: towards a peaceful coexistence

International Nuclear Information System (INIS)

Heitz, P.

2013-01-01

The most important hazard for a bat is the collision with a rotating blade. The risk of collision depends on the wrong positioning of a wind turbine in the hunting area of a local population of bats and on the complex behaviour of bats. All the 34 species of bats living in France are protected species. Recommendations issued by the ministry of ecology include to perform preliminary impact studies on bat population before the installation of a wind turbine farm, to perform impact studies during wind turbine operations and to take measures to have the least impact as possible. The number of wind farms being on the rise, the knowledge of the behaviour of bats is getting more accurate through the use of dedicated instruments. (A.C.)

Byers Auto Group: A Case Study Into The Economics, Zoning, and Overall Process of Installing Small Wind Turbines at Two Automotive Dealerships in Ohio (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Sinclair, K.; Oteri, F.

2011-05-01

This presentation provides the talking points about a case study on the installation of a $600,000 small wind project, the installation process, estimated annual energy production and percentage of energy needs met by the turbines.

Review of contemporary wind turbine concepts and their market penetration

International Nuclear Information System (INIS)

Hansen, A.D.; Iov, F.; Blaabjerg, F.; Hansen, L.H.

2004-01-01

The main aim of this paper is to investigate the market penetration and share of different wind turbine concepts during the years 1998-2002, a period when the increase in the wind power capacity is starting to mark an abrupt evolution (more than two GW per year). A detailed overview is performed based on suppliers market data and concept evaluation for each individual wind turbine type sold by the Top Ten suppliers over the selected five years. The investigation is processing information on a total number of approximately 90 wind turbine types from 13 different manufacturers, which have been on the Top Ten list of wind turbine suppliers during 1998 to 2002. The analysis is based on very comprehensive data, which cover approximately 76% of the accumulated world wind power installed at the end of 2002. The paper also provides an overall perspective on the contemporary wind turbine concepts, classified with respect to both their speed control ability and to their power control type. Trends for wind turbine concepts are discussed. (author)

Wind or water turbine power augmentation using the system of guiding surfaces

International Nuclear Information System (INIS)

Bashurin, V P; Ktitorov, L V; Lazareva, A S; Pletenev, F A; Budnikov, I N; Hatunkin, V Yu; Klevtsov, V A; Meshkov, E E; Novikova, I A; Yanbaev, G M

2016-01-01

As fluid flows through a conventional wind or hydro turbine, it slows from losing energy to extraction from a turbine and spreads out to a wider area. This results in a loss of turbine efficiency. In order to exploit wind or water flow power more effectively, it was suggested to place the turbine inside a system of specially designed airfoils (‘a flow booster’). One part of the booster (‘a nozzle’) improves the turbine performance by speeding up the flow acting on the turbine blades. The other part of the accelerating system (‘a diffuser’) creates a field of low pressure behind the turbine which helps to draw more mass flow to the turbine and avoid the loss of efficiency due to flow deceleration. The flow booster accumulates the kinetic energy of the flow (e.g. river flow or wind) in a small volume where the smaller turbine can be installed. Another possible application of the booster could be the improvement of wind turbine efficiency during low wind period. The present paper also discusses the possibility of kinetic energy accumulation by the use of several accelerating systems of different sizes—the smaller one can be installed inside the bigger one. It helps to accumulate even more kinetic energy on the turbine blades. We call this method the kinetic energy cumulation. Lab and field experiments and CFD simulations of shrouded turbine demonstrate significant increase in velocity in comparison of those for conventional (bare) turbines. (paper)

Multiple Lightning Discharges in Wind Turbines Associated with Nearby Cloud-to-Ground Lightning

DEFF Research Database (Denmark)

Candela Garolera, Anna; Cummins, Kenneth L.; Madsen, Søren Find

2015-01-01

This paper presents the analysis of five events where simultaneous lightning currents were registered in different wind turbines of a wind farm with lightning monitoring equipment installed. Measurements from current monitoring devices installed at the wind turbines and observations from auto......-triggering video cameras were correlated with data from the U.S. National Lighting Detection Network. In all five events, the correlation showed that a cloud-to-ground (CG) lightning stroke with high peak current struck the ground within 10 km of the affected turbines at the time of the currents in the wind...... by the nearby CG strokes, involving mechanisms that vary depending on the polarity of the associated CG stroke. The analysis also suggests that the event of upward lightning from wind turbines triggered by nearby lightning activity occurs very often and therefore it should be considered carefully...

Power Electronics for the Next Generation Wind Turbine System

DEFF Research Database (Denmark)

Ma, Ke

generation unit, are becoming crucial in the wind turbine system. The objective of this project is to study the power electronics technology used for the next generation wind turbines. Some emerging challenges as well as potentials like the cost of energy and reliability are going to be addressed. First...... conversion is pushed to multi-MW level with high power density requirement. It has also been revealed that thermal stress in the power semiconductors is closely related to many determining factors in the wind power application like the reliability, cost, power density, etc. therefore it is an important......The wind power generation has been steadily growing both for the total installed capacity and for the individual turbine size. Due to much more significant impacts to the power grid, the power electronics, which can change the behavior of wind turbines from an unregulated power source to an active...

Crack Monitoring of Operational Wind Turbine Foundations.

Science.gov (United States)

Perry, Marcus; McAlorum, Jack; Fusiek, Grzegorz; Niewczas, Pawel; McKeeman, Iain; Rubert, Tim

2017-08-21

The degradation of onshore, reinforced-concrete wind turbine foundations is usually assessed via above-ground inspections, or through lengthy excavation campaigns that suspend wind power generation. Foundation cracks can and do occur below ground level, and while sustained measurements of crack behaviour could be used to quantify the risk of water ingress and reinforcement corrosion, these cracks have not yet been monitored during turbine operation. Here, we outline the design, fabrication and field installation of subterranean fibre-optic sensors for monitoring the opening and lateral displacements of foundation cracks during wind turbine operation. We detail methods for in situ sensor characterisation, verify sensor responses against theoretical tower strains derived from wind speed data, and then show that measured crack displacements correlate with monitored tower strains. Our results show that foundation crack opening displacements respond linearly to tower strain and do not change by more than ±5 μ m. Lateral crack displacements were found to be negligible. We anticipate that the work outlined here will provide a starting point for real-time, long-term and dynamic analyses of crack displacements in future. Our findings could furthermore inform the development of cost-effective monitoring systems for ageing wind turbine foundations.

DOE-EPRI distributed wind Turbine Verification Program (TVP III)

Energy Technology Data Exchange (ETDEWEB)

McGowin, C.; DeMeo, E. [Electric Power Research Institute, Palo Alto, CA (United States); Calvert, S. [Dept. of Energy, Washington, DC (United States)] [and others

1997-12-31

In 1992, the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE) initiated the Utility Wind Turbine Verification Program (TVP). The goal of the program is to evaluate prototype advanced wind turbines at several sites developed by U.S. electric utility companies. Two six MW wind projects have been installed under the TVP program by Central and South West Services in Fort Davis, Texas and Green Mountain Power Corporation in Searsburg, Vermont. In early 1997, DOE and EPRI selected five more utility projects to evaluate distributed wind generation using smaller {open_quotes}clusters{close_quotes} of wind turbines connected directly to the electricity distribution system. This paper presents an overview of the objectives, scope, and status of the EPRI-DOE TVP program and the existing and planned TVP projects.

Wave run-up on offshore wind turbine foundations

DEFF Research Database (Denmark)

Baden, Elisabeth; Skourup, Jesper; Andersen, Thomas Lykke

2012-01-01

Wave run-up on appurtenances like boat landings, ladders, platforms and J-tubes of Offshore Wind Turbine foundations have in some cases caused severe and costly damage to these installations. A well-known example of large run-up was registered at the foundations of Horns Reef Offshore Wind Farm, ...

Offshore and onshore wind turbine wake meandering studied in an ABL wind tunnel

DEFF Research Database (Denmark)

Barlas, Emre; Buckingham, Sophia; Glabeke, Gertjan

2015-01-01

Scaled wind turbine models have been installed in the VKI L1-B atmospheric boundary layer wind tunnel at offshore and onshore conditions. Time-resolved measurements were carried out with three component hot wire anemometry and stereo-PIV in the middle vertical plane of the wake up to eleven turbine...... diameter downstream. The results show an earlier wake recovery for the onshore case. The effect of inflow conditions and the wind turbine’s working conditions on wake meandering was investigated. Wake meandering was detected by hot wire anemometry through a low frequency peak in the turbulent power...

Superconducting Wind Turbine Generators

Directory of Open Access Journals (Sweden)

Yunying Pan

2016-08-01

Full Text Available Wind energy is well known as a renewable energy because its clean and less polluted characteristic, which is the foundation of development modern wind electricity. To find more efficient wind turbine is the focus of scientists around the world. Compared from conventional wind turbines, superconducting wind turbine generators have advantages at zero resistance, smaller size and lighter weight. Superconducting wind turbine will inevitably become the main trends in this area. This paper intends to introduce the basic concept and principle of superconductivity, and compare form traditional wind turbine to obtain superiority, then to summary three proposed machine concept.While superconductivity have difficulty  in modern technology and we also have proposed some challenges in achieving superconducting wind turbine finally.

Bird casualties and wind turbines near the Kreekrak sluices of Zeeland

International Nuclear Information System (INIS)

Musters, C.J.M.; Noordervliet, M.A.W.; Ter Keurs, W.J.

1995-03-01

The impact of wind turbines on birds was investigated for an estuary, situated near the North Sea coast in the Dutch province of Zeeland, with large amount of bird migration. Five 250 kW, three-bladed 25m, 40 rpm turbines were installed on the western side of a dike. The distance between the turbines is 125 m. Since 1 April 1990 the turbines have been in action almost continuously. The study on the title subject was set up to investigate the number of bird casualties caused by the five wind turbines near the sluices of Kreekrak and the number that may be expected to be caused by a total of 20 turbines. The study also focused on the number of casualties among rare birds in relation to those among the common birds as a result of the wind turbines in the Kreekrak area. An area of 125 x 125 m around each wind turbine, consisting partly of land and partly of water, was searched for dead birds every other day during a period of one year (28 April 1990 - 29 April 1991). During this one-year period, the bodies of 26 birds of 17 different species were found; six birds were certainly or almost certainly killed by the turbines. In three other cases, the birds may have died because of the turbines, while in the case of eight birds, it was not possible to determine the cause of death. The remaining nine birds were not killed by the wind turbines. The annual number of bird victims expected following the installation of 20 wind turbines was estimated at a minimum of 7 and a maximum of 142. For each species a correlation was found between the number of victims and the estimated number of visitors to the area. This suggests that the rare species among the birds were not excessively endangered by the turbines. The number of bird casualties per turbine was low in comparison with the results of other Dutch investigations. On the basis of these results, it is concluded that there is no reason to advise against increasing the number of wind turbines near the sluices of Kreekrak to 20. 3

Concept Testing of a Simple Floating Offshore Vertical Axis Wind Turbine

DEFF Research Database (Denmark)

Friis Pedersen, Troels; Schmidt Paulsen, Uwe; Aagaard Madsen, Helge

2013-01-01

The wind energy community is researching new concepts for deeper sea offshore wind turbines. One such concept is the DeepWind concept. The concept is being assessed in a EU-FP7 project, called DeepWind. Objectives of this project are to assess large size wind turbines (5-20MW) based on the concept...... varying wind and wave conditions, and to compare such behaviour with computer code calculations. The concept turbine was designed and constructed by the project task partners, and all parts were assembled and installed at sea in the Roskilde fjord right next to DTU Risø campus. The turbine is under....... One task in the project is to test a 1kW concept rotor (not a scaled down MW size rotor) partly under field conditions in a fjord in Denmark, partly in a water tank under controlled conditions in Netherlands. The objective of testing the 1kW concept turbine is to verify the dynamical behaviour under...

Wind Turbine and Wind Power Plant Modelling Aspects for Power System Stability Studies

DEFF Research Database (Denmark)

Altin, Müfit; Hansen, Anca Daniela; Göksu, Ömer

2014-01-01

Large amount of wind power installations introduce modeling challenges for power system operators at both the planning and operational stages of power systems. Depending on the scope of the study, the modeling details of the wind turbine or the wind power plant are required to be different. A wind...... turbine model which is developed for the short-term voltage stability studies can be inaccurate and sufficient for the frequency stability studies. Accordingly, a complete and detailed wind power plant model for every kind of study is not feasible in terms of the computational time and also...... and wind power plants are reviewed for power system stability studies. Important remarks of the models are presented by means of simulations to emphasize the impact of these modelling details on the power system....

Status and perspectives of wind turbine installations in Italy

Energy Technology Data Exchange (ETDEWEB)

Barra, L; Arena, A; Mizzoni, G; Pirazzi, L [ENEA, Rome (Italy). Energy Dept.

1996-12-31

The article intends to illustrate the Italian situation in wind sector, giving some elements to explain why some delay is registered with respect to other European countries. Further than the present day situation, from which it can be concluded that the diffusion process is still commencing, being installed only 20 MW, the perspectives are discussed. Projects for plant installations totaling about 430 MW have been submitted to the electric utility. The actual realization of these important initiatives will probably depend on the ability to use wind energy as an occasion to sustain economic development of the involved zones. (author)

Status and perspectives of wind turbine installations in Italy

Energy Technology Data Exchange (ETDEWEB)

Barra, L.; Arena, A.; Mizzoni, G.; Pirazzi, L. [ENEA, Rome (Italy). Energy Dept.

1995-12-31

The article intends to illustrate the Italian situation in wind sector, giving some elements to explain why some delay is registered with respect to other European countries. Further than the present day situation, from which it can be concluded that the diffusion process is still commencing, being installed only 20 MW, the perspectives are discussed. Projects for plant installations totaling about 430 MW have been submitted to the electric utility. The actual realization of these important initiatives will probably depend on the ability to use wind energy as an occasion to sustain economic development of the involved zones. (author)

Status and perspectives of wind turbine installations in Italy

International Nuclear Information System (INIS)

Barra, L.; Arena, A.; Mizzoni, G.; Pirazzi, L.

1995-01-01

The article intends to illustrate the Italian situation in wind sector, giving some elements to explain why some delay is registered with respect to other European countries. Further than the present day situation, from which it can be concluded that the diffusion process is still commencing, being installed only 20 MW, the perspectives are discussed. Projects for plant installations totaling about 430 MW have been submitted to the electric utility. The actual realization of these important initiatives will probably depend on the ability to use wind energy as an occasion to sustain economic development of the involved zones. (author)

Design and fabrication of a low-cost Darrieus vertical-axis wind-turbine system, volume 2

Science.gov (United States)

1983-03-01

The fabrication, installation, and checkout of 100-kW 17 meter vertical axis wind turbines is described. Turbines are Darrieus-type VAWIs with rotors 17 meters and 25.15 meters in height. They can produce 100 kW of electric power at a cost of energy as low as 3 cents per kWh, in an 18-mph wind regime using 12% annualized costs. Four turbines were produced; three are installed and are operable. Contract results are documented.

Survey of variable speed operation of wind turbines

Energy Technology Data Exchange (ETDEWEB)

Carlson, Ola; Hylander, J.; Thorborg, K. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Electric Power Engineering

1996-12-01

During the last five years the production and operation of variable-speed wind turbines have advanced from a few experimental machines to a serial production of at least 10 MW of installed capacity of variable speed machines per week. The rated power of serial wind turbines is today around 600 kW and for the prototypes up to 3000 kW. Variable speed operation of wind turbines can be obtained with several different types of electrical generating systems, such as synchronous generators with diode rectifiers and thyristor inverters or induction generators with IGBT-converters, for the wide speed range. For the narrow speed range the wound motor induction generator with a rotor cascade or a controlled rotor resistance is preferable. The development of permanent magnetic material and the reduction of costs of the power electronic components have opened a possibility of designing cost-effective wind turbines with a directly driven generator. Pitch control together with variable speed will make it possible to limit the power variation within a few percent, 2 to 5 %, of the rated power. 7 refs, 4 figs, 2 tabs

Vibration-induced settlement of a slip-joint connection for offshore wind turbines

NARCIS (Netherlands)

Segeren, M.L.A.

2018-01-01

The majority of existing offshore wind turbines typically consist of a monopile foundation, a transition piece with a vertically positioned grouted connection, a turbine tower, and a turbine. Of the 2,653 offshore turbines that were installed by the end of 2015, 80 percent are supported by a

Dynamic modeling of a spar-type floating offshore wind turbine

NARCIS (Netherlands)

Savenije, L.B.; Ashuri, T.; Van Bussel, G.J.W.; Staerdahl, J.W.

2010-01-01

The installation of floating wind farms in deeper water is encouraged by the stronger and steadier wind, the lower visibility and noise impact, the absence of road restrictions, but also the absence or shortage of shallow water. In the summer of 2009, the first large-scale floating wind turbine

Wind Turbine Generator System Acoustic Noise Test Report for the Gaia Wind 11-kW Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Huskey, A.

2011-11-01

This report details the acoustic noise test conducted on the Gaia-Wind 11-kW wind turbine at the National Wind Technology Center. The test turbine is a two- bladed, downwind wind turbine with a rated power of 11 kW. The test turbine was tested in accordance with the International Electrotechnical Commission standard, IEC 61400-11 Ed 2.1 2006-11 Wind Turbine Generator Systems -- Part 11 Acoustic Noise Measurement Techniques.

Wind Turbines Adaptation to the Variability of the Wind Field

Science.gov (United States)

Ulianov, Yuriy; Martynenko, Gennadii; Misaylov, Vitaliy; Soliannikova, Iuliia

2010-05-01

including combined RF-acoustic antenna installed coaxially with the gondola of the wind power turbine. The work of the technique is synchronized with rotation of blades to eliminate their shielding action. Dangerous in terms of dynamic strength is the wind load pulse, the rise time which is comparable with the period of the natural frequency of the wind turbine elements (blade, tower, rotor, etc.). The amplitude decay of resonant vibrations at critical values of the speed of rotation can be realized through the use of mechanical elastic supports with nonlinear artificial dampers. They have a high coefficient of resistance, but may cause self-excited oscillations. We propose the way to deal with raised vibration of wind turbine elements at the expense of short-term increase of damping in the range of critical rotary axis speeds or during impulsive effects of wind loadings (wind gusts). This is possible through the use of non-linear electromagnetic dampers or active magnetic bearings. Their feature is the possibility of varying the mechanical stiffness and damping properties by changing the electrical parameters of electromagnets. The controlling of these parameters is carried out by the control system (CS) with the information feedback on the spatial-temporal structure of the wind field obtained from IRASS. In the composition of the CS can also be included the rotational speed sensor of the WPT rotor. This approach to the adaptation of wind turbines will allow to reduce vibration and to perform early compensation of the load on their components, which arise under the wind gusts. In addition, corrections about the wind field obtained with IRASS, would increase the mean power of WPT.

Output Power Smoothing Control for a Wind Farm Based on the Allocation of Wind Turbines

Directory of Open Access Journals (Sweden)

Ying Zhu

2018-06-01

Full Text Available This paper presents a new output power smoothing control strategy for a wind farm based on the allocation of wind turbines. The wind turbines in the wind farm are divided into control wind turbines (CWT and power wind turbines (PWT, separately. The PWTs are expected to output as much power as possible and a maximum power point tracking (MPPT control strategy combining the rotor inertia based power smoothing method is adopted. The CWTs are in charge of the output power smoothing for the whole wind farm by giving the calculated appropriate power. The battery energy storage system (BESS with small capacity is installed to be the support and its charge and discharge times are greatly reduced comparing with the traditional ESSs based power smoothing strategies. The simulation model of the permanent magnet synchronous generators (PMSG based wind farm by considering the wake effect is built in Matlab/Simulink to test the proposed power smoothing method. Three different working modes of the wind farm are given in the simulation and the simulation results verify the effectiveness of the proposed power smoothing control strategy.

Detecting wind turbine wakes with nacelle lidars

DEFF Research Database (Denmark)

Held, D. P.; Larvol, A.; Mann, Jakob

2017-01-01

variance is used as a detection parameter for wakes. A one month long measurement campaign, where a continuous-wave lidar on a turbine has been exposed to multiple wake situations, is used to test the detection capabilities. The results show that it is possible to identify situation where a downstream...... turbine is in wake by comparing the peak widths. The used lidar is inexpensive and brings instalments on every turbine within economical reach. Thus, the information gathered by the lidars can be used for improved control at wind farm level....

Wind turbines and transmission systems for offshore wind projects in planning stage

Energy Technology Data Exchange (ETDEWEB)

Madariaga, Ander; Martin, Jose Luis; Martinez de Alegria, Inigo; Zamora, Inmaculada [University of the Basque Country (UPV/EHU), Bilbao (Spain). Engineering Faculty; Ceballos, Salvador [Parque Tecnologico de Bizkaia, Derio (Spain). Tecnalia Research and Innovation

2012-07-01

This paper reviews the current situation of the offshore wind turbines (OWTs) and the transmission systems (TSs) for offshore wind projects in the planning stage. Bearing in mind that offshore wind projects can last between seven and ten years from the first environmental studies to the commissioning, research engineers from companies and academia consider the solutions already available, but also to the new proposals expected to be ready in time for the project under consideration. Regarding the wind energy conversion systems (WECSs) installed in the OWTs, their main characteristics are reviewed considering turbines in the 4.1 to 10.0 MW range. Regarding the TSs, the current situation of point-to-point HVAC and HVDC links is presented, as well as some ideas related to future DC grids currently under study. (orig.)

Effects of Capcitor Bank on Fault Ride Through Capibility of Induction Generator Based Wind Turbines

DEFF Research Database (Denmark)

Hu, Y; Chen, Zhe

2010-01-01

power system stability and supply security. Some existing wind turbines are still based on fixed speed induction generators, the effects of capacitor bank on such generators are discussed in this paper. The simulation study shows the capacitor bank may costeffectively improve the dynamic performance......Wind turbine installation is increasing rapidly. In some networks, wind power penetration is significantly high and the performance of wind turbine plays an important role in power system operation and control. Especially, the behavior of wind turbines during a power system disturbance would affect...

Variability of the Wind Turbine Power Curve

Directory of Open Access Journals (Sweden)

Mahesh M. Bandi

2016-09-01

Full Text Available Wind turbine power curves are calibrated by turbine manufacturers under requirements stipulated by the International Electrotechnical Commission to provide a functional mapping between the mean wind speed v ¯ and the mean turbine power output P ¯ . Wind plant operators employ these power curves to estimate or forecast wind power generation under given wind conditions. However, it is general knowledge that wide variability exists in these mean calibration values. We first analyse how the standard deviation in wind speed σ v affects the mean P ¯ and the standard deviation σ P of wind power. We find that the magnitude of wind power fluctuations scales as the square of the mean wind speed. Using data from three planetary locations, we find that the wind speed standard deviation σ v systematically varies with mean wind speed v ¯ , and in some instances, follows a scaling of the form σ v = C × v ¯ α ; C being a constant and α a fractional power. We show that, when applicable, this scaling form provides a minimal parameter description of the power curve in terms of v ¯ alone. Wind data from different locations establishes that (in instances when this scaling exists the exponent α varies with location, owing to the influence of local environmental conditions on wind speed variability. Since manufacturer-calibrated power curves cannot account for variability influenced by local conditions, this variability translates to forecast uncertainty in power generation. We close with a proposal for operators to perform post-installation recalibration of their turbine power curves to account for the influence of local environmental factors on wind speed variability in order to reduce the uncertainty of wind power forecasts. Understanding the relationship between wind’s speed and its variability is likely to lead to lower costs for the integration of wind power into the electric grid.

Composite wind turbine towers

Energy Technology Data Exchange (ETDEWEB)

Polyzois, D. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Civil Engineering

2008-07-01

This paper discussed experiments conducted to optimized the advanced composite materials such as fiberglass reinforced plastics (FRP) used to fabricate wind turbine towers. FRP materials are used in tubular steel, lattice, guyed, and reinforced concrete towers. The towers and turbine blades are transported in segments and assembled on-site, sometimes in offshore or remote locations.The FRP composites are used to build towers with a high strength-to-weight ratio as well as to provide resistance to chemical attacks and corrosion. Use of the materials has resulted in towers that do not require heavy installation equipment. Experimental programs were conducted to verify the structural behaviour of the tower structure's individual-scaled cells as well as to evaluate the performance of multi-cell assemblies. Joint assembly designs were optimized, and a filament winding machine was used to conduct the experimental study and to test individual cells. Failure mode analyses were conducted to determine local buckling and shear rupture. Tension, compression, and shear properties of the FRP materials were tested experimentally, and data from the test were then used to develop finite element models of the composite towers as well as to obtain load deflection curves and tip oscillation data. A case study of a 750 kW wind turbine in Churchill, Manitoba was used to test the design. tabs., figs.

Small wind turbines with timber blades for developing countries: Materials choice, development, installation and experiences

DEFF Research Database (Denmark)

Mishnaevsky, Leon; Freere, Peter; Sinha, Rakesh

2011-01-01

The low cost wind turbines with timber blades represent a good solution for the decentralized energy production in off-grid regions of developing countries. This paper summarizes the results of investigations on the mechanical testing and choice of timber for wind blades, testing of different...... of the blades and turbines. It was further demonstrated that the low cost wind turbines with timber blades represent a promising and viable option for the decentralized energy production in developing countries, which also opens new areas for businesses....

Wind Turbine Technologies

DEFF Research Database (Denmark)

Hansen, Anca Daniela

2017-01-01

, and with or without gearboxes, using the latest in power electronics, aerodynamics, and mechanical drive train designs [4]. The main differences between all wind turbine concepts developed over the years, concern their electrical design and control. Today, the wind turbines on the market mix and match a variety......, the design of wind turbines has changed from being convention driven to being optimized driven within the operating regime and market environment. Wind turbine designs have progressed from fixed speed, passive controlled and with drive trains with gearboxes, to become variable speed, active controlled......,6] and to implement modern control system strategies....

Wind field re-construction of 3D Wake measurements from a turbine-installed scanning lidar

DEFF Research Database (Denmark)

Mikkelsen, Torben Krogh; Herges, Tommy; Astrup, Poul

High-resolution wake flow measurements obtained from a turbine-mounted scanning lidar have been obtained from 1D to 5D behind a V27 test turbine. The measured line-of-sight projected wind speeds have, in connection with a fast CFD wind field reconstruction model, been used to generate 3D wind fie...

Experimental investigation on performance of crossflow wind turbine as effect of blades number

Science.gov (United States)

Kurniawati, Diniar Mungil; Tjahjana, Dominicus Danardono Dwi Prija; Santoso, Budi

2018-02-01

Urban living is one of the areas with large electrical power consumption that requires a power supply that is more than rural areas. The number of multi-storey buildings such as offices, hotels and several other buildings that caused electricity power consumption in urban living is very high. Therefore, energy alternative is needed to replace the electricity power consumption from government. One of the utilization of renewable energy in accordance with these conditions is the installation of wind turbines. One type of wind turbine that is now widely studied is a crossflow wind turbines. Crossflow wind turbine is one of vertical axis wind turbine which has good self starting at low wind speed condition. Therefore, the turbine design parameter is necessary to know in order to improve turbine performance. One of wind turbine performance parameter is blades number. The main purpose of this research to investigate the effect of blades number on crossflow wind turbine performance. The design of turbine was 0.4 × 0.4 m2 tested by experimental method with configuration on three kinds of blades number were 8,16 and 20. The turbine investigated at low wind speed on 2 - 5 m/s. The result showed that best performance on 16 blade number.

An investigation of the levels of electromagnetic radiation generated by wind turbines

International Nuclear Information System (INIS)

Morgan, C.A.

1992-01-01

The issue of electromagnetic interference is arising with some regularity as various wind energy projects throughout the UK reach the stage where local authority planning approval is sought. To many of the parties involved, wind turbines represent an unknown quantity and hence objections to their siting must be expected. Wind turbines may cause electromagnetic interference through two quite distinct processes. The first occurs when the wind turbine scatters electromagnetic signals passing through the area of the site and essentially, provides a second path between the transmitter and receiver of the signal. The second source of interference arises when signals generated within the wind turbine itself affect communications equipment or, indeed, any electronic circuitry. A case in point is a wind farm project under development by Bonython Estates of Cornwall. The aim of this project was to investigate the emissions from the wind turbines proposed for the Bonython development. This was achieved by means of field measurements on existing installations. (author)

Advanced Issues of Wind Turbine Modelling and Control

International Nuclear Information System (INIS)

Simani, Silvio

2015-01-01

The motivation for this paper comes from a real need to have an overview about the challenges of modelling and control for very demanding systems, such as wind turbine systems, which require reliability, availability, maintainability, and safety over power conversion efficiency. These issues have begun to stimulate research and development in the wide control community particularly for these installations that need a high degree of “sustainability”. Note that this topic represents a key point mainly for offshore wind turbines with very large rotors, since they are characterised by challenging modelling and control problems, as well as expensive and safety critical maintenance works. In this case, a clear conflict exists between ensuring a high degree of availability and reducing maintenance times, which affect the final energy cost. On the other hand, wind turbines have highly nonlinear dynamics, with a stochastic and uncontrollable driving force as input in the form of wind speed, thus representing an interesting challenge also from the modelling point of view. Suitable control methods can provide a sustainable optimisation of the energy conversion efficiency over wider than normally expected working conditions. Moreover, a proper mathematical description of the wind turbine system should be able to capture the complete behaviour of the process under monitoring, thus providing an important impact on the control design itself. In this way, the control scheme could guarantee prescribed performance, whilst also giving a degree of “tolerance” to possible deviation of characteristic properties or system parameters from standard conditions, if properly included in the wind turbine model itself. The most important developments in advanced controllers for wind turbines are addressed, and open problems in the areas of modelling of wind turbines are also outlined. (paper)

Aerodynamics of Wind Turbines

DEFF Research Database (Denmark)

Hansen, Martin Otto Laver

Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its second edition, it has been entirely updated and substantially extended to reflect advances in technology, research into rotor aerodynamics and the structural...... response of the wind turbine structure. Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element...... Momentum method is also covered, as are eigenmodes and the dynamic behavior of a turbine. The new material includes a description of the effects of the dynamics and how this can be modeled in an aeroelastic code, which is widely used in the design and verification of modern wind turbines. Further...

Design guidelines for H-Darrieus wind turbines: Optimization of the annual energy yield

International Nuclear Information System (INIS)

Bianchini, Alessandro; Ferrara, Giovanni; Ferrari, Lorenzo

2015-01-01

Highlights: • Proposal for a new design criterion for H-Darrieus turbines based on the energy-yield maximization. • 21,600 design cases analyzed to identify the best solutions for each installation site (i.e. average wind speed). • Critical analysis of the best design choices in terms of turbine shape, dimensions, airfoils and constraints. • Notable energy increase provided by the new design approach. • Each site requires a specific turbine concept to optimize the energy yield. - Abstract: H-Darrieus wind turbines are gaining popularity in the wind energy market, particularly as they are thought to represent a suitable solution even in unconventional installation areas. To promote the diffusion of this technology, industrial manufacturers are continuously proposing new and appealing exterior solutions, coupled with tempting rated-power offers. The actual operating conditions of a rotor over a year can be, however, very different from the nominal one and strictly dependent on the features of the installation site. Based on these considerations, a turbine optimization oriented to maximize the annual energy yield, instead of the maximum power, is thought to represent a more interesting solution. With this goal in mind, 21,600 test cases of H-Darrieus rotors were compared on the basis of their energy-yield capabilities for different annual wind distributions in terms of average speed. The wind distributions were combined with the predicted performance maps of the rotors obtained with a specifically developed numerical code based on a Blade Element Momentum (BEM) approach. The influence on turbine performance of the cut-in speed was accounted for, as well as the limitations due to structural loads (i.e. maximum rotational speed and maximum wind velocity). The analysis, carried out in terms of dimensionless parameters, highlighted the aerodynamic configurations able to ensure the largest annual energy yield for each wind distribution and set of aerodynamic

Pitchcontrol of wind turbines using model free adaptivecontrol based on wind turbine code

DEFF Research Database (Denmark)

Zhang, Yunqian; Chen, Zhe; Cheng, Ming

2011-01-01

value is only based on I/O data of the wind turbine is identified and then the wind turbine system is replaced by a dynamic linear time-varying model. In order to verify the correctness and robustness of the proposed model free adaptive pitch controller, the wind turbine code FAST which can predict......As the wind turbine is a nonlinear high-order system, to achieve good pitch control performance, model free adaptive control (MFAC) approach which doesn't need the mathematical model of the wind turbine is adopted in the pitch control system in this paper. A pseudo gradient vector whose estimation...... the wind turbine loads and response in high accuracy is used. The results show that the controller produces good dynamic performance, good robustness and adaptability....

The VGOT Darrieus wind turbine

Energy Technology Data Exchange (ETDEWEB)

Ponta, F.L.; Otero, A.D.; Lago, L. [University of Buenos Aires (Argentina). College of Engineering

2004-07-01

We present the actual state of development of a non-conventional new vertical-axis wind turbine. The concepts introduced here involve the constructive aspects of variable-geometry oval-trajectory (VGOT) Darrieus wind turbines. The key feature of a VGOT machine is that each blade slides over rails mounted on a wagon instead of rotating around a central vertical axis. Each wagon contains its own electrical generation system coupled to the power-wheels and the electricity is collected by a classical third rail system. The VGOT concept allows increasing the area swept by the blades, and hence the power output of the installation, without the structural problems and the low rotational speed associated with a classical Darrieus rotor of large diameter. We also propose some engineering solutions for the VGOT design and present a brief economic analysis of the feasibility of the project. (author)

Wind conditions for wind turbine design

Energy Technology Data Exchange (ETDEWEB)

Maribo Pedersen, B.

1999-04-01

Delegates from Europe and USA attended the meeting and discussed general aspects of wind conditions for wind turbine design. The subjects and the presented papers covered a very broad range of aspects of wind conditions and related influence on the wind turbine. (EHS)

Wind Turbines Wake Aerodynamics

DEFF Research Database (Denmark)

Vermeer, L.; Sørensen, Jens Nørkær; Crespo, A.

2003-01-01

The aerodynamics of horizontal axis wind turbine wakes is studied. The contents is directed towards the physics of power extraction by wind turbines and reviews both the near and the far wake region. For the near wake, the survey is restricted to uniform, steady and parallel flow conditions......, thereby excluding wind shear, wind speed and rotor setting changes and yawed conditions. The emphasis is put on measurements in controlled conditions.For the far wake, the survey focusses on both single turbines and wind farm effects, and the experimental and numerical work are reviewed; the main interest...... is to study how the far wake decays downstream, in order to estimate the effect produced in downstream turbines.The article is further restricted to horizontal axis wind turbines and excludes all other types of turbines....

Analysis of conditions favourable for small vertical axis wind turbines between building passages in urban areas of Sweden

Science.gov (United States)

Awan, Muhammad Rizwan; Riaz, Fahid; Nabi, Zahid

2017-05-01

This paper presents the analysis of installing the vertical axis wind turbines between the building passages on an island in Stockholm, Sweden. Based on the idea of wind speed amplification due to the venture effect in passages, practical measurements were carried out to study the wind profile for a range of passage widths in parallel building passages. Highest increment in wind speed was observed in building passages located on the periphery of sland as wind enters from free field. Wind mapping was performed in the island to choose the most favourable location to install the vertical axis wind turbines (VAWT). Using the annual wind speed data for location and measured amplification factor, energy potential of the street was calculated. This analysis verified that small vertical axis wind turbines can be installed in the passage centre line provided that enough space is provided for traffic and passengers.

Simplified formulae for the estimation of offshore wind turbines clutter on marine radars.

Science.gov (United States)

Grande, Olatz; Cañizo, Josune; Angulo, Itziar; Jenn, David; Danoon, Laith R; Guerra, David; de la Vega, David

2014-01-01

The potential impact that offshore wind farms may cause on nearby marine radars should be considered before the wind farm is installed. Strong radar echoes from the turbines may degrade radars' detection capability in the area around the wind farm. Although conventional computational methods provide accurate results of scattering by wind turbines, they are not directly implementable in software tools that can be used to conduct the impact studies. This paper proposes a simple model to assess the clutter that wind turbines may generate on marine radars. This method can be easily implemented in the system modeling software tools for the impact analysis of a wind farm in a real scenario.

Finite element methods in a simulation code for offshore wind turbines

Science.gov (United States)

Kurz, Wolfgang

1994-06-01

Offshore installation of wind turbines will become important for electricity supply in future. Wind conditions above sea are more favorable than on land and appropriate locations on land are limited and restricted. The dynamic behavior of advanced wind turbines is investigated with digital simulations to reduce time and cost in development and design phase. A wind turbine can be described and simulated as a multi-body system containing rigid and flexible bodies. Simulation of the non-linear motion of such a mechanical system using a multi-body system code is much faster than using a finite element code. However, a modal representation of the deformation field has to be incorporated in the multi-body system approach. The equations of motion of flexible bodies due to deformation are generated by finite element calculations. At Delft University of Technology the simulation code DUWECS has been developed which simulates the non-linear behavior of wind turbines in time domain. The wind turbine is divided in subcomponents which are represented by modules (e.g. rotor, tower etc.).

Discord amongst the wind turbine buyers with regard to Dutch wind turbine manufacturers

International Nuclear Information System (INIS)

Janse, F.

1992-01-01

In the Netherlands two medium-large manufacturers of wind turbines exist: NedWind (Hollandia Kloos) and Windmaster Nederland (Begemann Groep). Also Lagerwey, which constructs wind turbines for the private market (farmers, cooperatives), is important for the Dutch market and successfull in Germany. There is a tendency amongst the Dutch energy utilities, which cooperate in the foundation WindPlan, to buy wind turbines from foreign manufacturers. Some energy utilities want to take advantage of the most attractive offers, while others want to cooperate in building up a Dutch wind turbine industry. 5 ills

Turbulence and wind turbines

DEFF Research Database (Denmark)

Brand, Arno J.; Peinke, Joachim; Mann, Jakob

2011-01-01

The nature of turbulent flow towards, near and behind a wind turbine, the effect of turbulence on the electricity production and the mechanical loading of individual and clustered wind turbines, and some future issues are discussed.......The nature of turbulent flow towards, near and behind a wind turbine, the effect of turbulence on the electricity production and the mechanical loading of individual and clustered wind turbines, and some future issues are discussed....

The influence of a cubic building on a roof mounted wind turbine

International Nuclear Information System (INIS)

Micallef, Daniel; Sant, Tonio; Ferreira, Carlos

2016-01-01

The performance of a wind turbine located above a cubic building is not well understood. This issue is of fundamental importance for the design of small scale wind turbines. One variable which is of particular importance in this respect is the turbine height above roof level. In this work, the power performance of a small wind turbine is assessed as a function of the height above the roof of a generic cubic building. A 3D Computational Fluid Dynamics model of a 10m x 10m x 10m building is used with the turbine modelled as an actuator disc. Results have shown an improvement in the average power coefficient even in cases where the rotor is partially located within the roof separation zone. This goes against current notions of small wind turbine power production. This study can be of particular importance to guide the turbine installation height on building roof tops. (paper)

Comparison of multibody simulations and measurements of wind turbine gearboxes at Hansen’s 13 MW test facility

OpenAIRE

Marrant, Ben; Vanhollebeke, Frederik; Peeters, Joris

2010-01-01

Continuous up-scaling of wind turbine size into the multi-megawatt class, together with developments for off-shore installation are calling for new wind turbine configurations and technologies. High product reliability is a key factor in these developments, cascaded down to each component manufacturer in the supply chain. Increasing the reliability of wind turbine drive trains for wind turbines with ever increasing size requires dedicated simulation models which can provide more insight in th...

Designed for extreme weather conditions. Installation ship for wind power plants; Fuer extreme Wetterlagen ausgelegt. Installationsschiff fuer Windenergieanlagen

Energy Technology Data Exchange (ETDEWEB)

Wedel, Henning von [Waertsilae Deutschland GmbH, Hamburg (Germany)

2012-02-13

In recent years, Waertsilaehas gained a leadership position of special ships for the installation of wind turbines. The high-performance turbine installation ship Seawolf (HPTIV) is the latest in this series.

Wind turbines and infrasound

International Nuclear Information System (INIS)

Howe, B.

2006-01-01

This paper provided the results of a study conducted to assess the impacts of wind farm-induced infrasound on nearby residences and human populations. Infrasound occurs at frequencies below those considered as detectable by human hearing. Infrasonic levels caused by wind turbines are often similar to ambient levels of 85 dBG or lower that are caused by wind in the natural environment. This study examined the levels at which infrasound poses a threat to human health or can be considered as an annoyance. The study examined levels of infrasound caused by various types of wind turbines, and evaluated acoustic phenomena and characteristics associated with wind turbines. Results of the study suggested that infrasound near modern wind turbines is typically not perceptible to humans through either auditory or non-auditory mechanisms. However, wind turbines often create an audible broadband noise whose amplitude can be modulated at low frequencies. A review of both Canadian and international studies concluded that infrasound generated by wind turbines should not significantly impact nearby residences or human populations. 17 refs., 2 tabs., 4 figs

Wind generation systems for remote communities: market assessment and guidelines for wind turbines selection

International Nuclear Information System (INIS)

Brothers, C.

1993-06-01

Wind technology and its market potential in remote communities of the Canadian North were discussed. These communities, unserviced by the main utility electricity grid, generate their own electricity using high quality, expensive diesel fuel to power diesel driven generators. The logistics of delivering fuel to these remote communities is an expensive operation. Wind resource in many of these communities is substantial and wind energy is seen as a prime candidate for supplying electricity to many potential sites in the Arctic and also areas in Quebec and Newfoundland. However, the severe service (i.e., cold climate, remote locations with limited facilities) requires special considerations to ensure that equipment installed performs reliably. This report described some demonstration projects in northern Canada over the last ten years, where an understanding of the special needs of wind turbines in remote areas has been developed. A guide which assessed the suitability of wind turbines for Arctic applications was included to assist organisations in preparing requirements to be used in acquiring wind turbines for use in cold regions. Refs., tabs., figs

Draft-circular on wind turbines. Concept-circulaire wind turbines

Energy Technology Data Exchange (ETDEWEB)

1983-01-01

Criteria for providing licenses to build and operate a wind turbine are surveyed. Factors to consider are: characteristics of the landscape, density of population, town and country planning, environmental aspects (birds), safety and nuisance. National regulations for wind turbines will simplify licensing procedures and improve legal security.

Wind turbines and idiopathic symptoms

DEFF Research Database (Denmark)

Blanes-Vidal, Victoria; Schwartz, Joel

2016-01-01

Whether or not wind turbines pose a risk to human health is a matter of heated debate. Personal reactions to other environmental exposures occurring in the same settings as wind turbines may be responsible of the reported symptoms. However, these have not been accounted for in previous studies. We...... investigated whether there is an association between residential proximity to wind turbines and idiopathic symptoms, after controlling for personal reactions to other environmental co-exposures. We assessed wind turbine exposures in 454 residences as the distance to the closest wind turbine (Dw) and number...... of wind turbines

Assessing the representativeness of wind data for wind turbine site evaluation

Science.gov (United States)

Renne, D. S.; Corotis, R. B.

1982-01-01

Once potential wind turbine sites (either for single installations or clusters) are identified through siting procedures, actual evaluation of the sites must commence. This evaluation is needed to obtain estimates of wind turbine performance and to identify hazards to the machine from the turbulence component of the atmosphere. These estimates allow for more detailed project planning and for preliminary financing arrangements to be secured. The site evaluation process can occur in two stages: (1) utilizing existing nearby data, and (2) establishing and monitoring an onsite measurement program. Since step (2) requires a period of at least 1 yr or more from the time a potential site has been identified, step (1) is often an essential stage in the preliminary evaluation process. Both the methods that have been developed and the unknowns that still exist in assessing the representativeness of available data to a nearby wind turbine site are discussed. How the assessment of the representativeness of available data can be used to develop a more effective onsite meteorological measurement program is also discussed.

Wind turbine reliability :understanding and minimizing wind turbine operation and maintenance costs.

Energy Technology Data Exchange (ETDEWEB)

Walford, Christopher A. (Global Energy Concepts. Kirkland, WA)

2006-03-01

Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce cost of energy.

Project appraisal for small and medium size wind energy installation: The Italian wind energy policy effects

International Nuclear Information System (INIS)

Fera, M.; Iannone, R.; Macchiaroli, R.; Miranda, S.; Schiraldi, M.M.

2014-01-01

In the last few years, the distributed energy production from small wind turbines (i.e.<200 kWp) has developed into a relevant business opportunity for different investors in Italy. The market, especially in Italy, has rapidly grown, achieving 9 MWp only in 2011, with an increase from 1.5 MW in 2009 to 13.3 MW at the end of 2011. This paper reports the results of a case study on the installation of several small wind turbines. It aims to provide an analysis of the conditions in Italy that make it possible to install these machines and offer a reliable reference for designing, planning, and controlling small wind turbine projects while focusing on the strategic variables of time, cost, and quality used by typical enterprises in the investment projects. The results are relevant to investors as well as engineering, procurement, and construction companies involved in this new sector, which must understand Italy’s renewable energy policy and its effects in practice. Moreover, certain national energy policy conclusions are reported and discussed in this paper. To properly study the sector, the data on time, cost and quality are analysed using typical project management tools. - Highlights: • Focus on the Italian wind energy sector. • Analysis of Italian policy effects. • Focus on small/medium size wind energy machines

Investigations on the Effect of Radius Rotor in Combined Darrieus-Savonius Wind Turbine

Directory of Open Access Journals (Sweden)

Kaprawi Sahim

2018-01-01

Full Text Available Renewable sources of energy, abundant in availability, are needed to be exploited with adaptable technology. For wind energy, the wind turbine is very well adapted to generate electricity. Among the different typologies, small scale Vertical Axis Wind Turbines (VAWT present the greatest potential for off-grid power generation at low wind speeds. The combined Darrieus-Savonius wind turbine is intended to enhance the performance of the Darrieus rotor in low speed. In combined turbine, the Savonius buckets are always attached at the rotor shaft and the Darrieus blades are installed far from the shaft which have arm attaching to the shaft. A simple combined turbine offers two rotors on the same shaft. The combined turbine that consists of two Darrieus and Savonius blades was tested in wind tunnel test section with constant wind velocity and its performance was assessed in terms of power and torque coefficients. The study gives the effect of the radius ratio between Savonius and Darrieus rotor on the performance of the turbine. The results show that there is a significant influence on the turbine performance if the radius ratio was changed.

The influence of colour on the aesthetics of wind turbine generators

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

This paper summarises the results of studies examining the role that colour plays in reducing the visual impact of wind turbines and the development of a method for selecting the colour and pattern focusing on UK rural wind farms. Published material is reviewed, and visual factors relevant to visibility, factors influencing the choice of colour for buildings and other installations in the landscape, issues arising from the choice of colour, theories of camouflage, the testing of different colours, strategies for applying colour to wind turbines, the effectiveness of the different colours, and the effect of the different colour schemes on the visual impact of wind turbine arrays are addressed. Recommendations concerning colour selection are presented. A compact disc is provided with the paper. (UK)

Wind Turbine Generator System Power Performance Test Report for the ARE442 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

van Dam, J.; Jager, D.

2010-02-01

This report summarizes the results of a power performance test that NREL conducted on the ARE 442 wind turbine. This test was conducted in accordance with the International Electrotechnical Commission's (IEC) standard, Wind Turbine Generator Systems Part 12: Power Performance Measurements of Electricity Producing Wind Turbines, IEC 61400-12-1 Ed.1.0, 2005-12. However, because the ARE 442 is a small turbine as defined by IEC, NREL also followed Annex H that applies to small wind turbines. In these summary results, wind speed is normalized to sea-level air density.

Aerodynamics of wind turbines

DEFF Research Database (Denmark)

Hansen, Martin Otto Laver

Aerodynamics of Wind Turbines is the established essential text for the fundamental solutions to efficient wind turbine design. Now in its third edition, it has been substantially updated with respect to structural dynamics and control. The new control chapter now includes details on how to design...... Turbines (VAWT). Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method...... is also covered, as are eigenmodes and the dynamic behaviour of a turbine. The book describes the effects of the dynamics and how this can be modelled in an aeroelastic code, which is widely used in the design and verification of modern wind turbines. Furthermore, it examines how to calculate...

Habitat use of bats in relation to wind turbines revealed by GPS tracking

Science.gov (United States)

Roeleke, Manuel; Blohm, Torsten; Kramer-Schadt, Stephanie; Yovel, Yossi; Voigt, Christian C.

2016-07-01

Worldwide, many countries aim at countering global climate change by promoting renewable energy. Yet, recent studies highlight that so-called green energy, such as wind energy, may come at environmental costs, for example when wind turbines kill birds and bats. Using miniaturized GPS loggers, we studied how an open-space foraging bat with high collision risk with wind turbines, the common noctule Nyctalus noctula (Schreber, 1774), interacts with wind turbines. We compared actual flight trajectories to correlated random walks to identify habitat variables explaining the movements of bats. Both sexes preferred wetlands but used conventionally managed cropland less than expected based on availability. During midsummer, females traversed the land on relatively long flight paths and repeatedly came close to wind turbines. Their flight heights above ground suggested a high risk of colliding with wind turbines. In contrast, males recorded in early summer commuted straight between roosts and foraging areas and overall flew lower than the operating range of most turbine blades, suggesting a lower collision risk. Flight heights of bats suggest that during summer the risk of collision with wind turbines was high for most studied bats at the majority of currently installed wind turbines. For siting of wind parks, preferred bat habitats and commuting routes should be identified and avoided.

The VolturnUS 1:8 Floating Wind Turbine: Design, Construction, Deployment, Testing, Retrieval, and Inspection of the First Grid-Connected Offshore Wind Turbine in US

Energy Technology Data Exchange (ETDEWEB)

Dagher, Habib [Univ. of Maine, Orono, ME (United States); Viselli, Anthony [Univ. of Maine, Orono, ME (United States); Goupee, Andrew [Univ. of Maine, Orono, ME (United States); Kimball, Richard [Maine Maritime Academy, Castine, ME (United States); Allen, Christopher [Univ. of Maine, Orono, ME (United States)

2017-08-15

Volume II of the Final Report for the DeepCwind Consortium National Research Program funded by US Department of Energy Award Number: DE-EE0003278.001 summarizes the design, construction, deployment, testing, numerical model validation, retrieval, and post-deployment inspection of the VolturnUS 1:8-scale floating wind turbine prototype deployed off Castine, Maine on June 2nd, 2013. The 1:8 scale VolturnUS design served as a de-risking exercise for a commercial multi-MW VolturnUS design. The American Bureau of Shipping Guide for Building and Classing Floating Offshore Wind Turbine Installations was used to design the prototype. The same analysis methods, design methods, construction techniques, deployment methods, mooring, and anchoring planned for full-scale were used. A commercial 20kW grid-connected turbine was used and was the first offshore wind turbine in the US.

Design and construction of a simple blade pitch measurement system for small wind turbines

Energy Technology Data Exchange (ETDEWEB)

Whale, Jonathan [Research Institute of Sustainable Energy, Murdoch University, Perth, WA 6150 (Australia)

2009-02-15

For small wind turbines to be reliable they must have in place good mechanisms to protect themselves against very high winds or sudden removal of load. One common protection method in small wind turbines is that of blade feathering. It is important that the blade feathering mechanism of a small wind turbine is tested before the turbine is installed in the field. This paper presents a simple system for monitoring the blade feathering of a turbine with an overall component cost that small wind turbine manufacturers can afford. The Blade Pitch Measurement System (BPMS) has been designed and constructed by the Research Institute of Sustainable Energy (RISE) and aids small wind turbine manufacturers in testing and optimising the settings of the blade feathering mechanisms on their machines. The results show that the BPMS was successful in recording the behaviour of the blade feathering mechanism in field trials with a 20 kW and a 30 kW wind turbine. The BPMS displays significant potential as an effective, inexpensive system for small wind turbine manufacturers to ensure the reliability of their pitch regulating over-speed protection mechanisms. (author)

An integrated audio-visual impact tool for wind turbine installations

International Nuclear Information System (INIS)

Lymberopoulos, N.; Belessis, M.; Wood, M.; Voutsinas, S.

1996-01-01

An integrated software tool was developed for the design of wind parks that takes into account their visual and audio impact. The application is built on a powerful hardware platform and is fully operated through a graphic user interface. The topography, the wind turbines and the daylight conditions are realised digitally. The wind park can be animated in real time and the user can take virtual walks in it while the set-up of the park can be altered interactively. In parallel, the wind speed levels on the terrain, the emitted noise intensity, the annual energy output and the cash flow can be estimated at any stage of the session and prompt the user for rearrangements. The tool has been used to visually simulate existing wind parks in St. Breok, UK and Andros Island, Greece. The results lead to the conclusion that such a tool can assist to the public acceptance and licensing procedures of wind parks. (author)

Potential health impact of wind turbines

International Nuclear Information System (INIS)

2010-05-01

In response to public health concerns about wind turbines, a study was conducted to review the scientific evidence on the potential health effects of wind turbines. Several research questions were examined, including scientific evidence on the potential health impacts of wind turbines; the relationship between wind turbine noise and health; the relationship between low frequency sound, infrasound and health; assessment of exposure to wind turbines; wind turbine health and safety hazards and Ontario wind turbine setbacks; community consultation prior to wind farm construction and data gaps and research needs. The study showed that although some people living near wind turbines reported symptoms such as dizziness, headaches, and sleep disturbance, the scientific evidence available to date does not demonstrate a direct causal link between wind turbine noise and adverse health effects. The sound level from wind turbines at common residential setbacks is not sufficient to cause hearing impairment or other direct health effects, although some people may find it annoying. 41 refs., 1 appendix.

Onshore industrial wind turbine locations for the United States up to March 2014

Science.gov (United States)

Diffendorfer, James E.; Kramer, Louisa; Ancona, Zachary H.; Garrity, Christopher P.

2015-01-01

Wind energy is a rapidly growing form of renewable energy in the United States. While summary information on the total amounts of installed capacity are available by state, a free, centralized, national, turbine-level, geospatial dataset useful for scientific research, land and resource management, and other uses did not exist. Available in multiple formats and in a web application, these public domain data provide industrial-scale onshore wind turbine locations in the United States up to March 2014, corresponding facility information, and turbine technical specifications. Wind turbine records have been collected and compiled from various public sources, digitized or position verified from aerial imagery, and quality assured and quality controlled. Technical specifications for turbines were assigned based on the wind turbine make and model as described in public literature. In some cases, turbines were not seen in imagery or turbine information did not exist or was difficult to obtain. Uncertainty associated with these is recorded in a confidence rating.

Onshore industrial wind turbine locations for the United States up to March 2014.

Science.gov (United States)

Diffendorfer, Jay E; Kramer, Louisa A; Ancona, Zach H; Garrity, Christopher P

2015-11-24

Wind energy is a rapidly growing form of renewable energy in the United States. While summary information on the total amounts of installed capacity are available by state, a free, centralized, national, turbine-level, geospatial dataset useful for scientific research, land and resource management, and other uses did not exist. Available in multiple formats and in a web application, these public domain data provide industrial-scale onshore wind turbine locations in the United States up to March 2014, corresponding facility information, and turbine technical specifications. Wind turbine records have been collected and compiled from various public sources, digitized or position verified from aerial imagery, and quality assured and quality controlled. Technical specifications for turbines were assigned based on the wind turbine make and model as described in public literature. In some cases, turbines were not seen in imagery or turbine information did not exist or was difficult to obtain. Uncertainty associated with these is recorded in a confidence rating.

Offshore Code Comparison Collaboration within IEA Wind Task 23: Phase IV Results Regarding Floating Wind Turbine Modeling; Preprint

Energy Technology Data Exchange (ETDEWEB)

Jonkman, J.; Larsen, T.; Hansen, A.; Nygaard, T.; Maus, K.; Karimirad, M.; Gao, Z.; Moan, T.; Fylling, I.

2010-04-01

Offshore wind turbines are designed and analyzed using comprehensive simulation codes that account for the coupled dynamics of the wind inflow, aerodynamics, elasticity, and controls of the turbine, along with the incident waves, sea current, hydrodynamics, and foundation dynamics of the support structure. This paper describes the latest findings of the code-to-code verification activities of the Offshore Code Comparison Collaboration, which operates under Subtask 2 of the International Energy Agency Wind Task 23. In the latest phase of the project, participants used an assortment of codes to model the coupled dynamic response of a 5-MW wind turbine installed on a floating spar buoy in 320 m of water. Code predictions were compared from load-case simulations selected to test different model features. The comparisons have resulted in a greater understanding of offshore floating wind turbine dynamics and modeling techniques, and better knowledge of the validity of various approximations. The lessons learned from this exercise have improved the participants' codes, thus improving the standard of offshore wind turbine modeling.

Numerical Buckling Analysis of Large Suction Caissons for Wind Turbines on Deep Water

DEFF Research Database (Denmark)

Madsen, Søren; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

2013-01-01

Using large suction caissons for offshore wind turbines is an upcoming cost-effective technology also referred to as bucket foundations. During operation, the monopod bucket foundation is loaded by a large overturning moment from the wind turbine and the wave loads. However, during installation...... the suction caisson is loaded by external pressure (internal suction) due to evacuation of water inside the bucket and vertical forces due to gravity. The risk of structural buckling during installation of large-diameter suction caissons is addressed using numerical methods. Initial imperfect geometries...

Modeling energy production of solar thermal systems and wind turbines for installation at corn ethanol plants

Science.gov (United States)

Ehrke, Elizabeth

Nearly every aspect of human existence relies on energy in some way. Most of this energy is currently derived from fossil fuel resources. Increasing energy demands coupled with environmental and national security concerns have facilitated the move towards renewable energy sources. Biofuels like corn ethanol are one of the ways the U.S. has significantly reduced petroleum consumption. However, the large energy requirement of corn ethanol limits the net benefit of the fuel. Using renewable energy sources to produce ethanol can greatly improve its economic and environmental benefits. The main purpose of this study was to model the useful energy received from a solar thermal array and a wind turbine at various locations to determine the feasibility of applying these technologies at ethanol plants around the country. The model calculates thermal energy received from a solar collector array and electricity generated by a wind turbine utilizing various input data to characterize the equipment. Project cost and energy rate inputs are used to evaluate the profitability of the solar array or wind turbine. The current state of the wind and solar markets were examined to give an accurate representation of the economics of each industry. Eighteen ethanol plant locations were evaluated for the viability of a solar thermal array and/or wind turbine. All ethanol plant locations have long payback periods for solar thermal arrays, but high natural gas prices significantly reduce this timeframe. Government incentives will be necessary for the economic feasibility of solar thermal arrays. Wind turbines can be very profitable for ethanol plants in the Midwest due to large wind resources. The profitability of wind power is sensitive to regional energy prices. However, government incentives for wind power do not significantly change the economic feasibility of a wind turbine. This model can be used by current or future ethanol facilities to investigate or begin the planning process for a

Wind turbine clutter mitigation in coastal UHF radar.

Science.gov (United States)

Yang, Jing; Pan, Chao; Wang, Caijun; Jiang, Dapeng; Wen, Biyang

2014-01-01

Coastal UHF radar provides a unique capability to measure the sea surface dynamic parameters and detect small moving targets, by exploiting the low energy loss of electromagnetic waves propagating along the salty and good conducting ocean surface. It could compensate the blind zone of HF surface wave radar at close range and reach further distance than microwave radars. However, its performance is susceptible to wind turbines which are usually installed on the shore. The size of a wind turbine is much larger than the wavelength of radio waves at UHF band, which results in large radar cross section. Furthermore, the rotation of blades adds time-varying Doppler frequency to the clutter and makes the suppression difficult. This paper proposes a mitigation method which is based on the specific periodicity of wind turbine clutter and performed mainly in the time-frequency domain. Field experimental data of a newly developed UHF radar are used to verify this method, and the results prove its effectiveness.

Operation Design of Wind Turbines in Strong Wind Conditions

DEFF Research Database (Denmark)

Shen, Wen Zhong; Montes, Melissa Barroso; Odgaard, Peter Fogh

2012-01-01

and variable speed pitch regulated wind turbines. The variable speed design is more suitable for wind turbines to run at very high wind speeds which can help the turbine braking system to stop the turbine at the new "cut-out" wind speed. Reference power, rotational speed and pitch angle have been designed...... optimally. In order to reduce the possible increased loading, fatigue due to the wind gusts, control strategies have been considered for both constant sped and variable speed pitch regulated wind turbines. The control study shows that the designed controllers can reduce the standard deviations efficiently......In order to reduce the impact on the electrical grid from the shutdown of MW wind turbines at wind speeds higher than the cut-out wind speed of 25 m/s, we propose in this paper to run the turbines at high wind speeds up to 40 m/s. Two different operation designs are made for both constant speed...

Environmental assessment: Kotzebue Wind Installation Project, Kotzebue, Alaska

International Nuclear Information System (INIS)

1998-05-01

The DOE is proposing to provide financial assistance to the Kotzebue Electric Association to expand its existing wind installation near Kotzebue, Alaska. Like many rural Alaska towns, Kotzebue uses diesel-powered generators to produce its electricity, the high cost of which is currently subsidized by the Alaska State government. In an effort to provide a cost effective and clean source of electricity, reduce dependence on diesel fuel, and reduce air pollutants, the DOE is proposing to fund an experimental wind installation to test commercially available wind turbines under Arctic conditions. The results would provide valuable information to other Alaska communities experiencing similar dependence on diesel-powered generators. The environmental assessment for the proposed wind installation assessed impacts to biological resources, land use, electromagnetic interference, coastal zone, air quality, cultural resources, and noise. It was determined that the project does not constitute a major Federal action significantly affecting the quality of the human environment. Therefore, the preparation of an environmental impact statement is not required, and DOE has issued a Finding of No Significant Impact

Environmental assessment: Kotzebue Wind Installation Project, Kotzebue, Alaska

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-05-01

The DOE is proposing to provide financial assistance to the Kotzebue Electric Association to expand its existing wind installation near Kotzebue, Alaska. Like many rural Alaska towns, Kotzebue uses diesel-powered generators to produce its electricity, the high cost of which is currently subsidized by the Alaska State government. In an effort to provide a cost effective and clean source of electricity, reduce dependence on diesel fuel, and reduce air pollutants, the DOE is proposing to fund an experimental wind installation to test commercially available wind turbines under Arctic conditions. The results would provide valuable information to other Alaska communities experiencing similar dependence on diesel-powered generators. The environmental assessment for the proposed wind installation assessed impacts to biological resources, land use, electromagnetic interference, coastal zone, air quality, cultural resources, and noise. It was determined that the project does not constitute a major Federal action significantly affecting the quality of the human environment. Therefore, the preparation of an environmental impact statement is not required, and DOE has issued a Finding of No Significant Impact.

Coordinated Control of Wind Turbine and Energy Storage System for Reducing Wind Power Fluctuation

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kim, Chunghun [Hanyang University; Chung, Chung Choo [Hanyang University

2017-11-13

This paper proposes a coordinated control of wind turbine and energy storage system (ESS). Because wind power (WP) is highly dependent on variable wind speed and could induce a severe stability problem to power system especially when the WP has high penetration level. To solve this problem, many power generation corporations or grid operators recently use the ESS. It has very quick response and good performance for reducing the impact of WP fluctuation but has high cost for its installation. Therefore, it is very important to design the control algorithm considering both ESS capacity and grid reliability. Thus, we propose the control algorithm to mitigate the WP fluctuation by using the coordinated control between wind turbine and ESS considering ESS state of charge (SoC) and the WP fluctuation. From deloaded control according to WP fluctuation and ESS SoC management, we can expect the ESS lifespan expansion and improved grid reliability. The effectiveness of the proposed method is validated in MATLAB/Simulink considering power system including both wind turbine generator and conventional generators which react to system frequency deviation.

An Experimental Analysis of the Effect of Icing on Wind Turbine Rotor Blades

DEFF Research Database (Denmark)

Raja, Muhammad Imran; Hussain, Dil muhammed Akbar; Soltani, Mohsen

2016-01-01

Wind Turbine is highly nonlinear plant whose dynamics changes with change in aerodynamics of the rotor blade. Power extracted from the wind turbine is a function of coefficient of power (Cp). Wind turbine installed in the cold climate areas has an icing on its rotor blade which might change its...... aerodynamics. This paper is an experimental investigation of the aerodynamic changes occur due to effect of ice accumulated on the rotor blades of wind turbine. We have tested three small scale model of the NREL's 5MW rotor blade with same profile but simulated different icing effect on them. These models...... are printed with 3D printer and tested one by one in a Wind Tunnel. Lift, drag and moment coefficients are calculated from the measured experimental data and program WT-Perf based on blade-element momentum (BEM) theory is used to predict the performance of wind turbine. Cp curves generated from the test...

Analysis of the Flicker Level Produced by a Fixed-Speed Wind Turbine

Science.gov (United States)

Suppioni, Vinicius; P. Grilo, Ahda

2013-10-01

In this article, the analysis of the flicker emission during continuous operation of a mid-scale fixed-speed wind turbine connected to a distribution system is presented. Flicker emission is investigated based on simulation results, and the dependence of flicker emission on short-circuit capacity, grid impedance angle, mean wind speed, and wind turbulence is analyzed. The simulations were conducted in different programs in order to provide a more realistic wind emulation and detailed model of mechanical and electrical components of the wind turbine. Such aim is accomplished by using FAST (Fatigue, Aerodynamics, Structures, and Turbulence) to simulate the mechanical parts of the wind turbine, Simulink/MatLab to simulate the electrical system, and TurbSim to obtain the wind model. The results show that, even for a small wind generator, the flicker level can limit the wind power capacity installed in a distribution system.

Modeling the allocation and economic evaluation of PV panels and wind turbines in urban areas

NARCIS (Netherlands)

Mohammadi, S.; Vries, de B.; Schaefer, W.F.; Timmermans, H.

2014-01-01

A model for allocating PV panels and wind turbines in urban areas is developed. Firstly, it examines the spatial and technical requirements for the installation of PV panels and wind turbines and then evaluates their economic feasibilities in order to generate the cost effective electricity neutral

Reliability analysis for wind turbines with incomplete failure data collected from after the date of initial installation

International Nuclear Information System (INIS)

Guo Haitao; Watson, Simon; Tavner, Peter; Xiang Jiangping

2009-01-01

Reliability has an impact on wind energy project costs and benefits. Both life test data and field failure data can be used for reliability analysis. In wind energy industry, wind farm operators have greater interest in recording wind turbine operating data. However, field failure data may be tainted or incomplete, and therefore it needs a more general mathematical model and algorithms to solve the model. The aim of this paper is to provide a solution to this problem. A three-parameter Weibull failure rate function is discussed for wind turbines and the parameters are estimated by maximum likelihood and least squares. Two populations of German and Danish wind turbines are analyzed. The traditional Weibull failure rate function is also employed for comparison. Analysis shows that the three-parameter Weibull function can obtain more accuracy on reliability growth of wind turbines. This work will be helpful in the understanding of the reliability growth of wind energy systems as wind energy technologies evolving. The proposed three-parameter Weibull function is also applicable to the life test of the components that have been used for a period of time, not only in wind energy but also in other industries

A new generation of wind turbines; Une nouvelle generation d'eoliennes

Energy Technology Data Exchange (ETDEWEB)

Nica, H. [Tesnic, Laval, PQ (Canada)

2008-06-15

Although homeowners have expressed a desire to use wind energy to supply their electricity needs, many technical barriers have stood in the way of installing wind turbines in urban settings. This was due in part to three-bladed vertical axis turbines, high technical costs, limited performances in urban settings and questionable aesthetics. Tesnic has considered these issues and proposed a completely different turbine that uses a different method for extracting energy from the wind. The first approved 3.6 kW model should appear by the end of 2009. This new turbine is based on the same principal of the steam turbine patented in 1913 by Nikola Tesla. Instead of having blades, the Tesla turbine used closely spaced parallel disks and was recognized as being very robust with a high efficiency rating. Tesnic's new wind powered turbine is a vertical axis turbine with a series of valves that directs the wind on a rotor assembly of disk space. A series of blades on its circumference redirects the wind through the assembly of discs and accelerates the rotation of the rotor. The turbine extracts the wind energy in several ways, including conventional drag and lift, adherence and the vortex effect. This gives a 50 per cent added value of efficiency compared to other wind powered turbines. The global market for small wind powered energy is in full expansion. It has been projected that small turbines with 1 kW capacity will be abundant by 2020. It was noted that for household wind powered energy, the market must consider issues of cost, low maintenance, noise pollution, visual aesthetics, durability and safety. Wind energy can also be used in several industries, including plastics, composites, light metals, textiles and electronics. 2 figs.

Reliability Analysis of Wind Turbines

DEFF Research Database (Denmark)

Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

2008-01-01

In order to minimise the total expected life-cycle costs of a wind turbine it is important to estimate the reliability level for all components in the wind turbine. This paper deals with reliability analysis for the tower and blades of onshore wind turbines placed in a wind farm. The limit states...... consideres are in the ultimate limit state (ULS) extreme conditions in the standstill position and extreme conditions during operating. For wind turbines, where the magnitude of the loads is influenced by the control system, the ultimate limit state can occur in both cases. In the fatigue limit state (FLS......) the reliability level for a wind turbine placed in a wind farm is considered, and wake effects from neighbouring wind turbines is taken into account. An illustrative example with calculation of the reliability for mudline bending of the tower is considered. In the example the design is determined according...

Wind power installations in Switzerland - Regional planning basics and impact

International Nuclear Information System (INIS)

Ott, W.; Kaufmann, Y.; Steiner, P.; Gilgen, K.; Sartoris, A.

2008-01-01

This report published by the Swiss Federal Office of Energy (SFOE) takes a look at the basics of regional planning and its impact on the construction of wind-energy installations in Switzerland. The authors state that the planning and realisation of wind turbine installations is often time and resource consuming: this document presents and discusses the results obtained in a project that aimed to supply consolidated knowledge on project-relevant basics and their effect with respect to wind-energy installations. Experience gained in Switzerland and in other countries is discussed. This report on the basics of wind-energy planning with its detailed information formed the basis of a checklist described in a further report. In nine chapters, regional planning aspects, environment and landscape-relevant aspects, effects on the national and regional economies and social acceptance factors are discussed. Also, success-factors and possible solutions for the successful realisation of wind-energy projects are looked at.

Detection of Wind Evolution and Lidar Trajectory Optimization for Lidar-Assisted Wind Turbine Control

Directory of Open Access Journals (Sweden)

David Schlipf

2015-11-01

Full Text Available Recent developments in remote sensing are offering a promising opportunity to rethink conventional control strategies of wind turbines. With technologies such as lidar, the information about the incoming wind field - the main disturbance to the system - can be made available ahead of time. Initial field testing of collective pitch feedforward control shows, that lidar measurements are only beneficial if they are filtered properly to avoid harmful control action. However, commercial lidar systems developed for site assessment are usually unable to provide a usable signal for real time control. Recent research shows, that the correlation between the measurement of rotor effective wind speed and the turbine reaction can be modeled and that the model can be used to optimize a scan pattern. This correlation depends on several criteria such as turbine size, position of the measurements, measurement volume, and how the wind evolves on its way towards the rotor. In this work the longitudinal wind evolution is identified with the line-of-sight measurements of a pulsed lidar system installed on a large commercial wind turbine. This is done by staring directly into the inflowing wind during operation of the turbine and fitting the coherence between the wind at different measurement distances to an exponential model taking into account the yaw misalignment, limitation to line-of-sight measurements and the pulse volume. The identified wind evolution is then used to optimize the scan trajectory of a scanning lidar for lidar-assisted feedforward control in order to get the best correlation possible within the constraints of the system. Further, an adaptive filer is fitted to the modeled correlation to avoid negative impact of feedforward control because of uncorrelated frequencies of the wind measurement. The main results of the presented work are a first estimate of the wind evolution in front of operating wind turbines and an approach which manufacturers of

Advanced Offshore Wind Turbine/Foundation Concept for the Great Lakes

Energy Technology Data Exchange (ETDEWEB)

Afjeh, Abdollah A. [Univ. of Toledo, OH (United States); Windpower, Nautica [Nautica Windpower, Olmsted Falls, OH (United States); Marrone, Joseph [OCC COWI, Vancouver (Canada); Wagner, Thomas [Nautica Windpower, Olmsted Falls, OH (United States)

2013-08-29

This project investigated a conceptual 2-bladed rotor wind turbine design and assessed its feasibility for installation in the Great Lakes. The levelized cost of energy was used for this purpose. A location in Lake Erie near the coast of Cleveland, Ohio was selected as the application site. The loading environment was defined using wind and wave data collected at a weather station in Lake Erie near Cleveland. In addition, the probability distributions of the annual significant wave height and wind speed were determined. A model of the dependence of the above two quantities was also developed and used in the study of wind turbine system loads. Loads from ice floes and ridges were also included.The NREL 5 MW 3-bladed rotor wind turbine concept was used as the baseline design. The proposed turbine design employs variable pitch blade control with tip-brakes and a teeter mechanism. The rotor diameter, rated power and the tower dimensions were selected to closely match those of the NREL 5 MW wind turbine.A semi-floating gravity base foundation was designed for this project primarily to adapt to regional logistical constraints to transport and install the gravity base foundation. This foundation consists of, from bottom to top, a base plate, a buoyancy chamber, a taper zone, a column (with ice cone), and a service platform. A compound upward-downward ice cone was selected to secure the foundation from moving because of ice impact.The turbine loads analysis was based on International ElectroTechnical Committee (IEC) Standard 61400-1, Class III winds. The NREL software FAST was the primary computational tool used in this study to determine all design load cases. An initial set of studies of the dynamics of wind turbines using Automatic Dynamic Analysis of Mechanical Systems (ADAMS) demonstrated that FAST and ADAMS load predictions were comparable. Because of its relative simplicity and short run times, FAST was selected for this study. For ice load calculations, a method

Wind turbine control and monitoring

CERN Document Server

Luo, Ningsu; Acho, Leonardo

2014-01-01

Maximizing reader insights into the latest technical developments and trends involving wind turbine control and monitoring, fault diagnosis, and wind power systems, 'Wind Turbine Control and Monitoring' presents an accessible and straightforward introduction to wind turbines, but also includes an in-depth analysis incorporating illustrations, tables and examples on how to use wind turbine modeling and simulation software.   Featuring analysis from leading experts and researchers in the field, the book provides new understanding, methodologies and algorithms of control and monitoring, comput

Potential of carbon mitigation by vertical axis wind turbines in urban regions

International Nuclear Information System (INIS)

Pope, K.; Naterer, G.F.

2009-01-01

The potential of greenhouse gas reduction with vertical axis wind turbines (VAWTs) in urban centers is examined in this paper. Four different wind turbine designs are compared, in terms of greenhouse gas reduction and specific energy distribution of the wind energy resource. A VAWT can potentially improve power generation capability in turbulent regions, where wind conditions can be represented by an exponential function. Results are presented to demonstrate that a VAWT covering one square metre, installed in 50% of Toronto residential dwellings, could mitigate between 29,193 and 138,741 tonnes of CO 2 per year. (author)

Wind turbines and health

International Nuclear Information System (INIS)

Rideout, K.; Copes, R.; Bos, C.

2010-01-01

This document summarized the potential health hazards associated with wind turbines, such as noise and low frequency sound, vibration and infrasound; electromagnetic fields (EMF); shadow flicker; and ice throw and structural failure. Various symptoms can be attributed to wind turbines, including dizziness, sleep disruption, and headaches. A review of available research regarding potential health affects to residents living in close proximity to wind turbines showed that the sound level associated with wind turbines at common residential setbacks is not sufficient to damage hearing, but may lead to annoyance and sleep disturbance. Research has shown that wind turbines are not a significant source of EMF exposure, and although shadows caused by the blades may be annoying, they are not likely to cause epileptic seizures at normal operational speeds. The risk of injury from ice throw can be minimized with setbacks of 200 to 400 m. Examples of Canadian wind turbine setback guidelines and regulations were also offered. It was concluded that setbacks and operational guidelines can be utilized in combination to address safety hazards, sound levels, land use issues, and impacts on people. 46 refs., 2 tabs., 2 figs.

Buckling of Bucket Foundations During Installation

DEFF Research Database (Denmark)

Madsen, Søren

There is a great politically will to expand the green energy market in these times. A proven green technology is wind turbines. Wind turbines have been installed in great numbers on land over the last decades. However, the current development in wind turbine design leads to larger turbine sizes...... in order to reduce the cost of energy. This limits the on land application due to transportation limitations and unwillingness from prospect neighbours. Thus, offshore wind energy started developing over the last couple of years. Although installing the wind turbines offshore resolves the before men tioned...... issues, it brings up the cost of energy mainly due to increased installation and maintenance costs. A very large part—up to 30–50% using current technology—of the installation cost origins from the expenses related to the installation of foundations. A new foundation concept—the bucket foundation...

A numerical study on manoeuvrability of wind turbine installation vessel using OpenFOAM

Directory of Open Access Journals (Sweden)

Sungwook Lee

2015-05-01

Full Text Available In this study, a numerical prediction method on manoeuvrability of Wind Turbine Installation Vessel (WTIV is presented. Planar Motion Mechanism (PMM captive test for the bare hull of WTIV is carried out in the model basin and compared with the numerical results using RANS simulation based on Open-source Field Operation And Manipulation (OpenFOAM calculation to validate the developed method. The manoeuvrability of WTIV with skeg and/or without skeg is investigated using the numerical approach along with the captive model test. In the numerical calculations, the dynamic stability index which indicates the course keeping ability is evaluated and compared for three different hull configurations i.e. bare hull and other two hulls with center skeg and twin skeg. This paper proves that the numerical approach using RANS simulation can be readily applied to estimate the manoeuvrability of WTIV at the initial design stage.

Wind Turbine Providing Grid Support

DEFF Research Database (Denmark)

2011-01-01

changing the operation of the wind turbine to a more efficient working point.; When the rotational speed of the rotor reaches a minimum value, the wind turbine enters a recovery period to re-accelerate the rotor to the nominal rotational speed while further contributing to the stability of the electrical......A variable speed wind turbine is arranged to provide additional electrical power to counteract non-periodic disturbances in an electrical grid. A controller monitors events indicating a need to increase the electrical output power from the wind turbine to the electrical grid. The controller...... is arranged to control the wind turbine as follows: after an indicating event has been detected, the wind turbine enters an overproduction period in which the electrical output power is increased, wherein the additional electrical output power is taken from kinetic energy stored in the rotor and without...

Aerodynamics of wind turbines emerging topics

CERN Document Server

Amano, R S

2014-01-01

Focusing on Aerodynamics of Wind Turbines with topics ranging from Fundamental to Application of horizontal axis wind turbines, this book presents advanced topics including: Basic Theory for Wind turbine Blade Aerodynamics, Computational Methods, and Special Structural Reinforcement Technique for Wind Turbine Blades.

An assessment of the potential for business use of wind turbines on farms in Scotland

International Nuclear Information System (INIS)

Hunter, A.G.M.; Graham, R.; Morgan, O.W.

1998-01-01

High wind speeds on farms in Scotland, coupled with on-site demands for electricity, suggest there is potential for installing single wind turbines on these farms to generate electricity. The benefit of avoided costs for on-site supplies will help to lower the effective generating costs of surplus electricity for sale. Using a sensitivity analysis to examine a range of parameter settings for financial costs, wind speeds, and farm grants, it is shown that a turbine can be viable on a farm. The key to viability is to have correct and accurate matching between turbine and farm business, there being a place for both large turbines and small turbines under separate circumstances. There are scenarios where a wind turbine is viable on half the farms in Scotland. (Author)

Integrated analysis of wind turbines - The impact of power systems on wind turbine design

DEFF Research Database (Denmark)

Barahona Garzón, Braulio

Megawatt-size wind turbines nowadays operate in very complex environmental conditions, and increasingly demanding power system requirements. Pursuing a cost-effective and reliable wind turbine design is a multidisciplinary task. However nowadays, wind turbine design and research areas...... conditions that stem from disturbances in the power system. An integrated simulation environment, wind turbine models, and power system models are developed in order to take an integral perspective that considers the most important aeroelastic, structural, electrical, and control dynamics. Applications...... of the integrated simulation environment are presented. The analysis of an asynchronous machine, and numerical simulations of a fixedspeed wind turbine in the integrated simulation environment, demonstrate the effects on structural loads of including the generator rotor fluxes dynamics in aeroelastic studies. Power...

Equivalent models of wind farms by using aggregated wind turbines and equivalent winds

International Nuclear Information System (INIS)

Fernandez, L.M.; Garcia, C.A.; Saenz, J.R.; Jurado, F.

2009-01-01

As a result of the increasing wind farms penetration on power systems, the wind farms begin to influence power system, and therefore the modeling of wind farms has become an interesting research topic. In this paper, new equivalent models of wind farms equipped with wind turbines based on squirrel-cage induction generators and doubly-fed induction generators are proposed to represent the collective behavior on large power systems simulations, instead of using a complete model of wind farms where all the wind turbines are modeled. The models proposed here are based on aggregating wind turbines into an equivalent wind turbine which receives an equivalent wind of the ones incident on the aggregated wind turbines. The equivalent wind turbine presents re-scaled power capacity and the same complete model as the individual wind turbines, which supposes the main feature of the present equivalent models. Two equivalent winds are evaluated in this work: (1) the average wind from the ones incident on the aggregated wind turbines with similar winds, and (2) an equivalent incoming wind derived from the power curve and the wind incident on each wind turbine. The effectiveness of the equivalent models to represent the collective response of the wind farm at the point of common coupling to grid is demonstrated by comparison with the wind farm response obtained from the detailed model during power system dynamic simulations, such as wind fluctuations and a grid disturbance. The present models can be used for grid integration studies of large power system with an important reduction of the model order and the computation time

Wind turbine supply in Canada

International Nuclear Information System (INIS)

Snodin, H.

2007-01-01

This study reported on wind turbine supplies to the Canadian market. The report was written to address concerns for Canada's supply outlook in the near future due to the booming wind energy market. Turbine shortages have arisen as a result of continued growth in both European and North American markets. Long lead-times on turbine orders are now increasing the pressure to lock in turbine supply during the initial phases of the development process. Future growth of the wind energy industry will be impacted if turbine supply difficulties continue to contribute to uncertainties in the development process. The report provided an overview of the North American and global wind energy markets, as well as a summary of telephone interviews conducted with turbine suppliers. The implications for the future of turbine supply to the Canadian market were also analyzed. It was concluded that policy-makers should focus on supporting the expansion of manufacturing facilities for small wind turbines and control infrastructure in Canada 7 refs., 3 figs

Model Predictive Control of Wind Turbines

DEFF Research Database (Denmark)

Henriksen, Lars Christian

Wind turbines play a major role in the transformation from a fossil fuel based energy production to a more sustainable production of energy. Total-cost-of-ownership is an important parameter when investors decide in which energy technology they should place their capital. Modern wind turbines...... the need for maintenance of the wind turbine. Either way, better total-cost-of-ownership for wind turbine operators can be achieved by improved control of the wind turbines. Wind turbine control can be improved in two ways, by improving the model on which the controller bases its design or by improving...

WindPACT Reference Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rinker, Jennifer [Former National Renewable Energy Laboratory (NREL) employee

2018-04-02

To fully understand how loads and turbine cost scale with turbine size, it is necessary to have identical turbine models that have been scaled to different rated powers. The report presents the WindPACT baseline models, which are a series of four baseline models that were designed to facilitate investigations into the scalings of loads and turbine cost with size. The models have four different rated powers (750 kW, 1.5 MW, 3.0 MW, and 5.0 MW), and each model was designed to its specified rated power using the same design methodology. The models were originally implemented in FAST_AD, the predecessor to NREL's open-source wind turbine simulator FAST, but have yet to be implemented in FAST. This report contains the specifications for all four WindPACT baseline models - including structural, aerodynamic, and control specifications - along with the inherent assumptions and equations that were used to calculate the model parameters. It is hoped that these baseline models will serve as extremely useful resources for investigations into the scalings of costs, loads, or optimization routines.

Annoyance rating of wind turbine noise

International Nuclear Information System (INIS)

Iredale, R.

1993-01-01

Annoyance rating is important, but more important still is agreement on techniques for formulating minimal complaint criteria for design and specification purposes thus integrating noise control into the plant at the outset. A minimal complaint design criteria is suggested that finds its origin in the logic and techniques used successfully over many years for a wide range of power plant and other installations. The criterion is based on the masking of the wind turbine noise by the wind generated background noise. Satisfactory use of the criterion depends on the specification of inaudibility for the tones generated by the mechanical plant. Wind turbines generate more drive train noise than is realized and this contains many tones which tend to characterize the noise. Reduction of drive train noise would not only reduce the overall noise level but also give it a more acceptable character providing a margin against complaint in unusual circumstances of propagation. This requires very careful design of noise and vibration control in individual components. Vibration isolation between the support structures and the nacelle also requires careful attention. (UK)

Wind turbine noise diagnostics

International Nuclear Information System (INIS)

Richarz, W.; Richarz, H.

2009-01-01

This presentation proposed a self-consistent model for broad-band noise emitted from modern wind turbines. The simple source model was consistent with the physics of sound generation and considered the unique features of wind turbines. Although the acoustics of wind turbines are similar to those of conventional propellers, the dimensions of wind turbines pose unique challenges in diagnosing noise emission. The general features of the sound field were deduced. Source motion and source directivity appear to be responsible for amplitude variations. The amplitude modulation is likely to make wind-turbine noise more audible, and may be partly responsible for annoyance that has been reported in the literature. Acoustic array data suggests that broad-band noise is emitted predominantly during the downward sweep of each rotor blade. Source motion and source directivity account for the observed pattern. Rotor-tower interaction effects are of lesser importance. Predicted amplitude modulation ranges from 1 dB to 6dB. 2 refs., 9 figs.

National Renewable Energy Laboratory program on lightning risk and wind turbine generator protection

Energy Technology Data Exchange (ETDEWEB)

Muljadi, E. [National Renewable Energy Lab., Golden, CO (United States); McNiff, B. [McNiff Light Industry, Blue Hill, ME (United States)

1997-12-31

In the early development of wind turbine generators (WTG) in the United States, wind farms were primarily located in California where lightning activity is the lowest in the United States. As such, lightning protection for wind turbines was not considered to be a major issue for designers or wind farm operators. However, wind turbine installations are expanding into the Midwest, Southwest and other regions of the United States where lightning activity is significantly more intense and lightning damage to wind turbines is more common. There is a growing need, therefore, to better understand lightning activity on wind farms and to improve wind turbine lightning protection systems. In support of the U.S. Department of Energy/Electric Power Research Institute (DOE/EPRI) Utility Wind Turbine Verification Program (TVP), the National Renewable Energy Laboratory (NREL) has recently begun to take steps to determine the extent of damage due to lightning and the effectiveness of various lightning protection techniques for wind power plants. Working through the TVP program, NREL will also perform outreach and education to (1) help manufacturers to provide equipment that is adequately designed to survive lightning, (2) make sure that operators are aware of effective safety procedures, and (3) help site designers and wind farm developers take the risk of lightning into account as effectively as possible.

Power control for wind turbines in weak grids: Concepts development

DEFF Research Database (Denmark)

Bindner, H.

1999-01-01

will make wind power more firm and possible to connect to weaker grids. So, when the concept is matured, theexpectation is that for certain wind power installations, the cost of the power control is paid back as added wind power capacity value and saved grid reinforcement costs. Different systems...... and analyze methods and technologies for making it viable to utilize more of the wind potential in remote areas. The suggestion is to develop a power control concept for wind turbines which will even out thepower fluctuations and make it possible to increase the wind energy penetration. The main options...... are to combine wind power with a pumped hydro power storage or with an AC/DC converter and battery storage. The AC/DC converter can either be an "add-on" typeor it can be designed as an integrated part of a variable speed wind turbine. The idea is that combining wind power with the power control concept...

Wind turbine

Science.gov (United States)

Cheney, Jr., Marvin C.

1982-01-01

A wind turbine of the type having an airfoil blade (15) mounted on a flexible beam (20) and a pitch governor (55) which selectively, torsionally twists the flexible beam in response to wind turbine speed thereby setting blade pitch, is provided with a limiter (85) which restricts unwanted pitch change at operating speeds due to torsional creep of the flexible beam. The limiter allows twisting of the beam by the governor under excessive wind velocity conditions to orient the blades in stall pitch positions, thereby preventing overspeed operation of the turbine. In the preferred embodiment, the pitch governor comprises a pendulum (65,70) which responds to changing rotor speed by pivotal movement, the limiter comprising a resilient member (90) which engages an end of the pendulum to restrict further movement thereof, and in turn restrict beam creep and unwanted blade pitch misadjustment.

Wind turbine power performance measurement with the use of spinner anemometry

DEFF Research Database (Denmark)

Demurtas, Giorgio

The spinner anemometer was patented by DTU in 2004 and licenced to ROMO Wind in 2011. By 2015 the spinner anemometer was installed on several hundred wind turbines for yaw misalignment measurements. The goal of this PhD project was to investigate the feasibility of use of spinner anemometry......-mast and spinner anemometer were then compared. Application of the NTF from one turbine to the other was made with a difference of only 0.38% in AEP. Different methods of analysis of fast sampled measurements such as the Langevin power curve were tested, concluding that the method of bins (IEC61400...... measurements was further improved with an innovation step to calibrate without use of the yaw position sensor, saving cost and time of installing the additional yaw sensor. The so called "wind speed response method" was validated by comparing 27 different calibration tests to the fist methods. This method...

Material Composition of Bucket Foundation Transition Piece for Offshore Wind Turbines

DEFF Research Database (Denmark)

Nezhentseva, Anastasia; Andersen, Lars; Ibsen, Lars Bo

2010-01-01

In Denmark, production of renewable energy is focused on offshore wind turbines, since they make little if any inconvenience for residents in inhabited areas. High requirements are placed on the installation of the foundations which can cost about 30% of the total cost of the wind turbine....... This paper deals with the transition piece for a relatively novel type of foundation, the so-called suction bucket (caisson), focusing on the design of a transition piece connecting the turbine column with a suction bucket used as a monopod foundation for an offshore wind turbine. Since the current design...... practice is limited to the use of steel-flange-reinforced shear panels for the transition piece—a production that requires extensive welding work—a desirable solution is to find a material that provides lower cost and easier manufacturing without compromising the strength and stiffness. The paper compares...

Aerodynamic performance prediction of Darrieus-type wind turbines

Directory of Open Access Journals (Sweden)

Ion NILĂ

2010-06-01

Full Text Available The prediction of Darrieus wind turbine aerodynamic performances provides the necessarydesign and operational data base related to the wind potential. In this sense it provides the type ofturbine suitable to the area where it is to be installed. Two calculation methods are analyzed for arotor with straight blades. The first one is a global method that allows an assessment of the turbinenominal power by a brief calculation. This method leads to an overestimation of performances. Thesecond is the calculation method of the gust factor and momentum which deals with the pale as beingcomposed of different elements that don’t influence each other. This method, developed based on thetheory of the turbine blades, leads to values close to the statistical data obtained experimentally. Thevalues obtained by the calculation method of gust factor - momentum led to the concept of a Darrieusturbine, which will be tested for different wind values in the INCAS subsonic wind tunnel.

Research on the aerodynamic characteristics of a lift drag hybrid vertical axis wind turbine

Directory of Open Access Journals (Sweden)

Xiaojing Sun

2016-01-01

Full Text Available Compared with a drag-type vertical axis wind turbines, one of the greatest advantages for a lift-type vertical axis wind turbines is its higher power coefficient (Cp. However, the lift-type vertical axis wind turbines is not a self-starting turbine as its starting torque is very low. In order to combine the advantage of both the drag-type and the lift-type vertical axis wind turbines, a lift drag hybrid vertical axis wind turbines was designed in this article and its aerodynamics and starting performance was studied in detail with the aid of computational fluid dynamics simulations. Numerical results indicate that the power coefficient of this lift drag hybrid vertical axis wind turbines declines when the distance between its drag-type blades and the center of rotation of the turbine rotor increases, whereas its starting torque can be significantly improved. Studies also show that unlike the lift-type vertical axis wind turbines, this lift drag hybrid-type vertical axis wind turbines could be able to solve the problem of low start-up torque. However, the installation position of the drag blade is very important. If the drag blade is mounted very close to the spindle, the starting torque of the lift drag hybrid-type vertical axis wind turbines may not be improved at all. In addition, it has been found that the power coefficient of the studied vertical axis wind turbines is not as good as expected and possible reasons have been provided in this article after the pressure distribution along the surfaces of the airfoil-shaped blades of the hybrid turbine was analyzed.

New guidelines for wind turbine gearboxes

Energy Technology Data Exchange (ETDEWEB)

McNiff, B. [McNiff Light Industry, Blue Hill, ME (United States); Errichello, R. [GEARTECH, Townsend, MT (United States)

1997-12-31

The American Gear Manufacturers Association in cooperation with the American Wind Energy Association will soon be publishing AGMA/AWEA 921-A97 {open_quotes}Recommended Practices for Design and Specification of Gearboxes for Wind Turbine Generator Systems.{close_quotes} Much has been learned about the unique operation and loading of gearboxes in wind turbine applications since the burgeoning of the modern wind turbine industry in the early 1980`s. AGMA/AWEA 921-A97 documents this experience in a manner that provides valuable information to assist gear manufacturers and wind turbine designers, operators, and manufacturers in developing reliable wind turbine gearboxes. The document provides information on procurement specification development, wind turbine architecture, environmental considerations, and gearbox load determination, as well as the design, manufacturing, quality assurance, lubrication, operation and maintenance of wind turbine gearboxes. This paper presents the salient parts of the practices recommended in AGMA/AWEA 921-A97.

Wind-driven roof turbines: a novel way to improve ventilation for TB infection control in health facilities.

Directory of Open Access Journals (Sweden)

Helen Cox

Full Text Available OBJECTIVE: Tuberculosis transmission in healthcare facilities contributes significantly to the TB epidemic, particularly in high HIV settings. Although improving ventilation may reduce transmission, there is a lack of evidence to support low-cost practical interventions. We assessed the efficacy of wind-driven roof turbines to achieve recommended ventilation rates, compared to current recommended practices for natural ventilation (opening windows, in primary care clinic rooms in Khayelitsha, South Africa. METHODS: Room ventilation was assessed (CO₂ gas tracer technique in 4 rooms where roof turbines and air-intake grates were installed, across three scenarios: turbine, grate and window closed, only window open, and only turbine and grate open, with concurrent wind speed measurement. 332 measurements were conducted over 24 months. FINDINGS: For all 4 rooms combined, median air changes per hour (ACH increased with wind speed quartiles across all scenarios. Higher median ACH were recorded with open roof turbines and grates, compared to open windows across all wind speed quartiles. Ventilation with open turbine and grate exceeded WHO-recommended levels (60 Litres/second/patient for 95% or more of measurements in 3 of the 4 rooms; 47% in the remaining room, where wind speeds were lower and a smaller diameter turbine was installed. CONCLUSION: High room ventilation rates, meeting recommended thresholds, may be achieved using wind-driven roof turbines and grates, even at low wind speeds. Roof turbines and air-intake grates are not easily closed by staff, allowing continued ventilation through colder periods. This simple, low-cost technology represents an important addition to our tools for TB infection control.

Wind-driven roof turbines: a novel way to improve ventilation for TB infection control in health facilities.

Science.gov (United States)

Cox, Helen; Escombe, Rod; McDermid, Cheryl; Mtshemla, Yolanda; Spelman, Tim; Azevedo, Virginia; London, Leslie

2012-01-01

Tuberculosis transmission in healthcare facilities contributes significantly to the TB epidemic, particularly in high HIV settings. Although improving ventilation may reduce transmission, there is a lack of evidence to support low-cost practical interventions. We assessed the efficacy of wind-driven roof turbines to achieve recommended ventilation rates, compared to current recommended practices for natural ventilation (opening windows), in primary care clinic rooms in Khayelitsha, South Africa. Room ventilation was assessed (CO₂ gas tracer technique) in 4 rooms where roof turbines and air-intake grates were installed, across three scenarios: turbine, grate and window closed, only window open, and only turbine and grate open, with concurrent wind speed measurement. 332 measurements were conducted over 24 months. For all 4 rooms combined, median air changes per hour (ACH) increased with wind speed quartiles across all scenarios. Higher median ACH were recorded with open roof turbines and grates, compared to open windows across all wind speed quartiles. Ventilation with open turbine and grate exceeded WHO-recommended levels (60 Litres/second/patient) for 95% or more of measurements in 3 of the 4 rooms; 47% in the remaining room, where wind speeds were lower and a smaller diameter turbine was installed. High room ventilation rates, meeting recommended thresholds, may be achieved using wind-driven roof turbines and grates, even at low wind speeds. Roof turbines and air-intake grates are not easily closed by staff, allowing continued ventilation through colder periods. This simple, low-cost technology represents an important addition to our tools for TB infection control.

Development of a representative model of a wind turbine in order to study the installation of several machines on a wind park

International Nuclear Information System (INIS)

Jourieh, M.

2007-12-01

This thesis is devoted to the study of aerodynamics in wind turbines. It is divided into two main parts, one is experimental, and the other deals with modelling and numerical simulation. The velocity field downstream from a three-bladed wind turbine with a horizontal axis is explored in the wind tunnel at ENSAM-Paris. Two measurement techniques are used: hot wire anemometry and Particle Image Velocimetry (PIV). Experimental work gives a clear idea of the structure of the near wake and provides useful data to validate the numerical simulations and the hybrid models which are studied in this thesis. In the work concerning numerical simulation, two hybrid models are defined and implemented: a model of actuator disc and a model of actuator cylinder, coupled with a simulation based on the numerical resolution of the Navier-Stokes equations. These models are validated by the power of the wind turbine and on the velocity field in the near wake of the rotor. The numerical results are compared with the experimental data resulting from the tests carried out by the NREL for NREL phase II and VI cases. The experimental and numerical velocity fields are also compared in the wake of a wind turbine Rutland 503. In both validation cases, power and wake, the experimental data are in accordance with the results provided by the hybrid models. After this validation, the interaction between several wind turbines is studied and quantified. The tested hybrid models are also used to study the interaction between identical wind turbines placed one behind the other. The obtained results highlight the effect of spacing between the machines as well as the effect of free stream velocity. (author)

Small Wind Turbine Technology Assessment

International Nuclear Information System (INIS)

Avia Aranda, F.; Cruz Cruz, I.

1999-01-01

The result of the study carried out under the scope of the ATYCA project Test Plant of Wind Systems for Isolated Applications, about the state of art of the small wind turbine technology (wind turbines with swept area smaller than 40 m 2 ) is presented. The study analyzes the collected information on 60 models of wind turbines from 23 manufacturers in the worldwide market. Data from Chinese manufacturers, that have a large participation in the total number of small wind turbines in operation, are not included, due to the unavailability of the technical information. (Author) 15 refs

Wind Turbine Converter Control Interaction with Complex Wind Farm Systems

DEFF Research Database (Denmark)

Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

2013-01-01

. The same wind turbine converter control strategy is evaluated in two different wind farms. It is emphasised that the grid-side converter controller should be characterised by sufficient harmonic/noise rejection and adjusted depending on wind farms to which it is connected. Various stability indices......This study presents wind turbine converter stability analysis of wind farms in frequency domain. The interaction between the wind turbine control system and the wind farm structure in wind farms is deeply investigated. Two wind farms (i.e. Horns Rev II and Karnice) are taken into consideration...... in this study. It is shown that wind farm components, such as long high-voltage alternating current cables and park transformers, can introduce significant low-frequency series resonances seen from the wind turbine terminals that can affect wind turbine control system operation and overall wind farm stability...

Noise immission from wind turbines

International Nuclear Information System (INIS)

1999-01-01

The project has dealt with practical ways to reduce the influence of background noise caused by wind acting on the measuring microphones. The uncertainty of measured noise emission (source strength) has been investigated. The main activity was a Round Robin Test involving measurements by five laboratories at the same wind turbine. Each laboratory brought its own instrumentation and performed the measurements and analyses according to their interpretation. The tonality of wind turbine noise is an essential component of the noise impact on the environment. In the present project the uncertainty in the newest existing methods for assessing tonality was investigated. The project included noise propagation measurements in different weather conditions around wind turbines situated in different types of terrain. The results were used to validate a noise propagation model developed in the project. Finally, the project also included a study with listeners evaluating recordings of wind turbine noise. The results are intended as guidance for wind turbine manufacturers in identifying the aspects of wind turbine noise most important to annoyance. (author)

Overview of Modelling and Advanced Control Strategies for Wind Turbine Systems

Directory of Open Access Journals (Sweden)

Silvio Simani

2015-11-01

Full Text Available The motivation for this paper comes from a real need to have an overview of the challenges of modelling and control for very demanding systems, such as wind turbine systems, which require reliability, availability, maintainability, and safety over power conversion efficiency. These issues have begun to stimulate research and development in the wide control community particularly for these installations that need a high degree of “sustainability”. Note that this represents a key point for offshore wind turbines, since they are characterised by expensive and/or safety critical maintenance work. In this case, a clear conflict exists between ensuring a high degree of availability and reducing maintenance times, which affect the final energy cost. On the other hand, wind turbines have highly nonlinear dynamics, with a stochastic and uncontrollable driving force as input in the form of wind speed, thus representing an interesting challenge also from the modelling point of view. Suitable control methods can provide a sustainable optimisation of the energy conversion efficiency over wider than normally expected working conditions. Moreover, a proper mathematical description of the wind turbine system should be able to capture the complete behaviour of the process under monitoring, thus providing an important impact on the control design itself. In this way, the control scheme could guarantee prescribed performance, whilst also giving a degree of “tolerance” to possible deviation of characteristic properties or system parameters from standard conditions, if properly included in the wind turbine model itself. The most important developments in advanced controllers for wind turbines are also briefly referenced, and open problems in the areas of modelling of wind turbines are finally outlined.

Simplified model of wind turbines with doubly-fed induction generator

Energy Technology Data Exchange (ETDEWEB)

Timbus, Adrian; Korba, Petr [ABB Corporate Research, Baden-Daettwil (Switzerland); Vilhunen, Antti; Pepe, Giuseppe; Seman, Slavomir; Niiranen, Jouko [ABB Oy, Helsinki (Finland)

2011-07-01

With an ever increasing pace of wind power installations around the world, the necessity of studying the functionality of the power system with intermittent generation becomes a critical necessity. Power system studies have been carried out by different organizations, using mainly generic models of turbines available in most utilized software tools such as PSS/E, PowerFactory, PSLF, etc. Very often the system operators ask for models of turbines which represent a specific vendor, hence vendor specific models become also available in these tools. These are necessary to evaluate a realistic response of the grid when a particular technology is used for the wind turbines. This paper elaborates on the development of a simplified model of a wind turbine equipped with Doubly-Fed Induction Generator. The model is meant to be suitable for power system studies and should reflect the concept provided by ABB. This model comprises a series of state machines which reflect the functionality of the turbine from start-up until shut-down due to high wind speeds. In addition, attention and efforts were focused to provide the right functionality during low voltage values, - the so called low voltage ride through feature - and to support the grid after voltage sag. (orig.)

Investigation of wind turbine effects on Evapotranspiration using surface energy balance model based on satellite-derived data

Science.gov (United States)

hassanpour Adeh, E.; Higgins, C. W.

2014-12-01

Wind turbines have been introduced as an energy source that does not require a large expenditure of water. However, recent simulation results indicate that wind turbines increase evaporation rates from the nearby land. In this research the effect of wind energy on irrigated agriculture is determined using a Surface Energy Balance Algorithm (SEBAL) on Landsat data spanning a 30 year interval. The analysis allows the characterization of evapotranspiration (ET) before and after wind turbine installations. The time history of ET from Landsat data will be presented for several major wind farms across the US. These data will be used to determine the impact on water demand due to presence of wind turbines.

Reliability assessment of Wind turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2015-01-01

Wind turbines can be considered as structures that are in between civil engineering structures and machines since they consist of structural components and many electrical and machine components together with a control system. Further, a wind turbine is not a one-of-a-kind structure...... but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...

Maximizing Energy Capture of Fixed-Pitch Variable-Speed Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

Pierce, K.; Migliore, P.

2000-08-01

Field tests of a variable-speed, stall-regulated wind turbine were conducted at a US Department of Energy Laboratory. A variable-speed generating system, comprising a doubly-fed generator and series-resonant power converter, was installed on a 275-kW, downwind, two-blade wind turbine. Gearbox, generator, and converter efficiency were measured in the laboratory so that rotor aerodynamic efficiency could be determined from field measurement of generator power. The turbine was operated at several discrete rotational speeds to develop power curves for use in formulating variable-speed control strategies. Test results for fixed-speed and variable-speed operation are presented along with discussion and comparison of the variable-speed control methodologies. Where possible, comparisons between fixed-speed and variable-speed operation are shown.

CFD analysis of a Darrieus wind turbine

Science.gov (United States)

Niculescu, M. L.; Cojocaru, M. G.; Pricop, M. V.; Pepelea, D.; Dumitrache, A.; Crunteanu, D. E.

2017-07-01

The Darrieus wind turbine has some advantages over the horizontal-axis wind turbine. Firstly, its tip speed ratio is lower than that of the horizontal-axis wind turbine and, therefore, its noise is smaller, privileging their placement near populated areas. Secondly, the Darrieus wind turbine does needs no orientation mechanism with respect to wind direction in contrast to the horizontal-axis wind turbine. However, the efficiency of the Darrieus wind turbine is lower than that of the horizontal-axis wind turbine since its aerodynamics is much more complex. With the advances in computational fluids and computers, it is possible to simulate the Darrieus wind turbine more accurately to understand better its aerodynamics. For these reasons, the present papers deals with the computational aerodynamics of a Darrieus wind turbine applying the state of the art of CFD methods (anisotropic turbulence models, transition from laminar to turbulent, scale adaptive simulation) to better understand its unsteady behavior.

Test location Guetsch, Switzerland for wind-power installations; Teststandort fuer Windkraftanlagen Guetsch. Vorstudie

Energy Technology Data Exchange (ETDEWEB)

Schaffner, B.; Cattin, R.; Schilter, Ch.

2007-07-15

This illustrated technical report for the Swiss Federal Office of Energy (SFOE) describes work done on the preliminary project for providing test facilities for wind-power installations on the 'Guetsch' location in the Swiss Alps. In the context of the Alpine Test Site Guetsch project, which involves meteorological measurements and wind turbine performance analysis research, a comprehensive infrastructure for the acquisition of climate data and the performance of wind turbines has been defined. This work is to be carried out by the Swiss Federal Office of Meteorology and Climatology MeteoSwiss and the company Meteotest within the framework of the COST Action 727 2005 - 2008 of the European Union. The aim of this preliminary study is to identify the possibilities for the realisation of an alpine test site for wind turbines based on the existing infrastructure. The economic and technical conditions for the testing of both large and small wind turbines are discussed. Topics examined include site ownership and access, infrastructure and measurement systems, financing possibilities and a timeline for implementation.

Statistical Evaluation of the Identified Structural Parameters of an idling Offshore Wind Turbine

International Nuclear Information System (INIS)

Kramers, Hendrik C.; Van der Valk, Paul L.C.; Van Wingerden, Jan-Willem

2016-01-01

With the increased need for renewable energy, new offshore wind farms are being developed at an unprecedented scale. However, as the costs of offshore wind energy are still too high, design optimization and new innovations are required for lowering its cost. The design of modern day offshore wind turbines relies on numerical models for estimating ultimate and fatigue loads of the turbines. The dynamic behavior and the resulting structural loading of the turbines is determined for a large part by its structural properties, such as the natural frequencies and damping ratios. Hence, it is important to obtain accurate estimates of these modal properties. For this purpose stochastic subspace identification (SSI), in combination with clustering and statistical evaluation methods, is used to obtain the variance of the identified modal properties of an installed 3.6MW offshore wind turbine in idling conditions. It is found that one is able to obtain confidence intervals for the means of eigenfrequencies and damping ratios of the fore-aft and side-side modes of the wind turbine. (paper)

SENECA NATION FINAL REPORT Installation of a 1.5MW WIND TURBINE

Energy Technology Data Exchange (ETDEWEB)

Giacobbe, Anthony [Seneca Nation, Salamanca, NY (United States)

2017-09-21

In February 2014, Seneca Energy and the Seneca Nation officially kicked off the Cattaraugus wind turbine project. The project began with a nine month NEPA study, which resulted in a Finding of No Significant Impact on 10/5/2015. The Seneca Construction Management Company was responsible for the oversight of the civil and foundation construction which commenced shortly after the FONSI was finalized. In April 2017, the Seneca Nation paid its first $25 credit to residents enrolled in the “Seneca Electricity Credit Program”. The $25 credit is applied directly to resident’s utility invoices and will total $300 of savings every year and ~$8,000 of savings over the project lifecycle. The Seneca Nation has already paid $40,000 towards resident’s electricity bills since the commissioning of the wind turbine in April 2017. The Seneca Electricity Credit Program was one of the primary driving factors for the project and we continue to have additional residents enroll for the program each month. Our goal is to continue to add residents to our credit program and assist them in keeping electricity rates down, so that they can use their money for other necessary living expenses. The Seneca Nation and Seneca Energy are extremely proud of the Cattaraugus wind turbine as well as all of the other exciting energy projects taking place on territory. We are continuing to follow our Strategic Energy Plan as we move forward towards achieving energy self-sufficiency.

Wind Climate Parameters for Wind Turbine Fatigue Load Assessment

DEFF Research Database (Denmark)

Toft, Henrik Stensgaard; Svenningsen, Lasse; Moser, Wolfgang

2016-01-01

Site-specific assessment of wind turbine design requires verification that the individual wind turbine components can survive the site-specific wind climate. The wind turbine design standard, IEC 61400-1 (third edition), describes how this should be done using a simplified, equivalent wind climate...... climate required by the current design standard by comparing damage equivalent fatigue loads estimated based on wind climate parameters for each 10 min time-series with fatigue loads estimated based on the equivalent wind climate parameters. Wind measurements from Boulder, CO, in the United States...

European wind turbine catalogue

International Nuclear Information System (INIS)

1994-01-01

The THERMIE European Community programme is designed to promote the greater use of European technology and this catalogue contributes to the fulfillment of this aim by dissemination of information on 50 wind turbines from 30 manufacturers. These turbines are produced in Europe and are commercially available. The manufacturers presented produce and sell grid-connected turbines which have been officially approved in countries where this approval is acquired, however some of the wind turbines included in the catalogue have not been regarded as fully commercially available at the time of going to print. The entries, which are illustrated by colour photographs, give company profiles, concept descriptions, measured power curves, prices, and information on design and dimension, safety systems, stage of development, special characteristics, annual energy production, and noise pollution. Lists are given of wind turbine manufacturers and agents and of consultants and developers in the wind energy sector. Exchange rates used in the conversion of the prices of wind turbines are also given. Information can be found on the OPET network (organizations recognised by the European Commission as an Organization for the Promotion of Energy Technologies (OPET)). An article describes the development of the wind power industry during the last 10-15 years and another article on certification aims to give an overview of the most well-known and acknowledged type approvals currently issued in Europe. (AB)

75 FR 27583 - Job Corps: Final Finding of No Significant Impact (FONSI) for Small Vertical Wind Turbine and...

Science.gov (United States)

2010-05-17

... CFR 11.11(d), gives final notice of the proposed construction of a small vertical axis wind turbine... (FONSI) for Small Vertical Wind Turbine and Solar Installation at the Paul Simon Job Corps Center Located... impact. This notice serves as the Final Finding of No Significant Impact (FONSI) for Small Vertical Wind...

Influence of Icing on the Modal Behavior of Wind Turbine Blades

Directory of Open Access Journals (Sweden)

Sudhakar Gantasala

2016-10-01

Full Text Available Wind turbines installed in cold climate sites accumulate ice on their structures. Icing of the rotor blades reduces turbine power output and increases loads, vibrations, noise, and safety risks due to the potential ice throw. Ice accumulation increases the mass distribution of the blade, while changes in the aerofoil shapes affect its aerodynamic behavior. Thus, the structural and aerodynamic changes due to icing affect the modal behavior of wind turbine blades. In this study, aeroelastic equations of the wind turbine blade vibrations are derived to analyze modal behavior of the Tjaereborg 2 MW wind turbine blade with ice. Structural vibrations of the blade are coupled with a Beddoes-Leishman unsteady attached flow aerodynamics model and the resulting aeroelastic equations are analyzed using the finite element method (FEM. A linearly increasing ice mass distribution is considered from the blade root to half-length and thereafter constant ice mass distribution to the blade tip, as defined by Germanischer Lloyd (GL for the certification of wind turbines. Both structural and aerodynamic properties of the iced blades are evaluated and used to determine their influence on aeroelastic natural frequencies and damping factors. Blade natural frequencies reduce with ice mass and the amount of reduction in frequencies depends on how the ice mass is distributed along the blade length; but the reduction in damping factors depends on the ice shape. The variations in the natural frequencies of the iced blades with wind velocities are negligible; however, the damping factors change with wind velocity and become negative at some wind velocities. This study shows that the aerodynamic changes in the iced blade can cause violent vibrations within the operating wind velocity range of this turbine.

Status of the technology development of large scale HTS generators for wind turbine

Energy Technology Data Exchange (ETDEWEB)

Le, T. D.; Kim, J. H.; Kim, D. J.; Boo, C. J.; Kim, H. M. [Jeju National University, Jeju (Korea, Republic of)

2015-06-15

Large wind turbine generators with high temperature superconductors (HTS) are in incessant development because of their advantages such as weight and volume reduction and the increased efficiency compared with conventional technologies. In addition, nowadays the wind turbine market is growing in a function of time, increasing the capacity and energy production of the wind farms installed and increasing the electrical power for the electrical generators installed. As a consequence, it is raising the wind power energy contribution for the global electricity demand. In this study, a forecast of wind energy development will be firstly emphasized, then it continue presenting a recent status of the technology development of large scale HTSG for wind power followed by an explanation of HTS wire trend, cryogenics cooling systems concept, HTS magnets field coil stability and other technological parts for optimization of HTS generator design-operating temperature, design topology, field coil shape and level cost of energy, as well. Finally, the most relevant projects and designs of HTS generators specifically for offshore wind power systems are also mentioned in this study.

Status of the technology development of large scale HTS generators for wind turbine

International Nuclear Information System (INIS)

Le, T. D.; Kim, J. H.; Kim, D. J.; Boo, C. J.; Kim, H. M.

2015-01-01

Large wind turbine generators with high temperature superconductors (HTS) are in incessant development because of their advantages such as weight and volume reduction and the increased efficiency compared with conventional technologies. In addition, nowadays the wind turbine market is growing in a function of time, increasing the capacity and energy production of the wind farms installed and increasing the electrical power for the electrical generators installed. As a consequence, it is raising the wind power energy contribution for the global electricity demand. In this study, a forecast of wind energy development will be firstly emphasized, then it continue presenting a recent status of the technology development of large scale HTSG for wind power followed by an explanation of HTS wire trend, cryogenics cooling systems concept, HTS magnets field coil stability and other technological parts for optimization of HTS generator design-operating temperature, design topology, field coil shape and level cost of energy, as well. Finally, the most relevant projects and designs of HTS generators specifically for offshore wind power systems are also mentioned in this study

Performance of a 3 kW wind turbine generator with variable pitch control system

International Nuclear Information System (INIS)

Nagai, Baku M.; Ameku, Kazumasa; Roy, Jitendro Nath

2009-01-01

A prototype 3 kW horizontal upwind type wind turbine generator of 4 m in diameter has been designed and examined under real wind conditions. The machine was designed based on the concept that even small wind turbines should have a variable pitch control system just as large wind turbines, especially in Japan where typhoons occur at least once a year. A characteristic of the machine is the use of a worm and gear system with a stepping motor installed in the center of the hub, and the rotational main shaft. The machine is constructed with no mechanical breaking system so as to avoid damage from strong winds. In a storm, the wind turbine is slowed down by adjusting the pitch angle and the maximum electrical load. Usually the machine is controlled at several stages depending on the rotational speed of the blades. Two control methods have been applied: the variable pitch angle, and regulation of the generator field current. The characteristics of the generator under each rotational speed and field current are first investigated in the laboratory. This paper describes the performances of the wind turbine in terms of the functions of wind turbine rotational speed, generated outputs, and its stability for wind speed changes. The expected performances of the machine have been confirmed under real wind conditions and compared with numerical simulation results. The wind turbine showed a power coefficient of 0.257 under the average wind speed of 7.3 m/s.

Computational modelling of an operational wind turbine and validation with LIDAR

Science.gov (United States)

Creech, Angus; Fruh, Wolf-Gerrit; Clive, Peter

2010-05-01

We present a computationally efficient method to model the interaction of wind turbines with the surrounding flow, where the interaction provides information on the power generation of the turbine and the generated wake behind the turbine. The turbine representation is based on the principle of an actuator volume, whereby the energy extraction and balancing forces on the fluids are formulated as body forces which avoids the extremely high computational costs of boundary conditions and forces. Depending on the turbine information available, those forces can be derived either from published turbine performance specifications or from their rotor and blade design. This turbine representation is then coupled to a Computational Fluid Dynamics package, in this case the hr-adaptive Finite-Element code Fluidity from Imperial College, London. Here we present a simulation of an operational 950kW NEG Micon NM54 wind turbine installed in the west of Scotland. The calculated wind is compared with LIDAR measurements using a Galion LIDAR from SgurrEnergy. The computational domain extends over an area of 6km by 6km and a height of 750m, centred on the turbine. The lower boundary includes the orography of the terrain and surface roughness values representing the vegetation - some forested areas and some grassland. The boundary conditions on the sides are relaxed Dirichlet conditions, relaxed to an observed prevailing wind speed and direction. Within instrumental errors and model limitations, the overall flow field in general and the wake behind the turbine in particular, show a very high degree of agreement, demonstrating the validity and value of this approach. The computational costs of this approach are such that it is possible to extend this single-turbine example to a full wind farm, as the number of required mesh nodes is given by the domain and then increases only linearly with the number of turbines

Nonlinear Dynamics of Wind Turbine Wings

DEFF Research Database (Denmark)

Larsen, Jesper Winther

, large wind turbines become increasingly flexible and dynamically sensitive. This project focuses on the structural analysis of highly flexible wind turbine wings, and the aerodynamic loading of wind turbine wings under large changes in flow field due to elastic deformations and changing wind conditions....

Operation and control of large wind turbines and wind farms

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Poul; Hansen, Anca D.; Thomsen, Kenneth (and others)

2005-09-01

This report is the final report of a Danish research project 'Operation and control of large wind turbines and wind farms'. The objective of the project has been to analyse and assess operational strategies and possibilities for control of different types of wind turbines and different wind farm concepts. The potentials of optimising the lifetime/energy production ratio by means of using revised operational strategies for the individual wind turbines are investigated. Different strategies have been simulated, where the power production is decreased to an optimum when taking loads and actual price of produced electricity into account. Dynamic models and control strategies for the wind farms have also been developed, with the aim to optimise the operation of the wind farms considering participation in power system control of power (frequency) and reactive power (voltage), maximise power production, keep good power quality and limit mechanical loads and life time consumption. The project developed models for 3 different concepts for wind farms. Two of the concepts use active stall controlled wind turbines, one with AC connection and one with modern HVDC/VSC connection of the wind farm. The third concept is based on pitch controlled wind turbines using doubly fed induction generators. The models were applied to simulate the behaviour of the wind farm control when they were connected to a strong grid, and some initial simulations were performed to study the behaviour of the wind farms when it was isolated from the main grid on a local grid. Also the possibility to use the available information from the wind turbine controllers to predict the wind speed has been investigated. The main idea has been to predict the wind speed at a wind turbine using up-wind measurements of the wind speed in another wind turbine. (au)

Wind turbine technology principles and design

CERN Document Server

Adaramola, Muyiwa

2014-01-01

IntroductionPart I: AerodynamicsWind Turbine Blade Design; Peter J. Schubel and Richard J. CrossleyA Shrouded Wind Turbine Generating High Output Power with Wind-Lens Technology; Yuji Ohya and Takashi KarasudaniEcomoulding of Composite Wind Turbine Blades Using Green Manufacturing RTM Process; Brahim AttafAerodynamic Shape Optimization of a Vertical-Axis Wind Turbine Using Differential Evolution; Travis J. Carrigan, Brian H. Dennis, Zhen X. Han, and Bo P. WangPart II: Generators and Gear Systems

Dynamic modeling and simulation of wind turbines

International Nuclear Information System (INIS)

Ghafari Seadat, M.H.; Kheradmand Keysami, M.; Lari, H.R.

2002-01-01

Using wind energy for generating electricity in wind turbines is a good way for using renewable energies. It can also help to protect the environment. The main objective of this paper is dynamic modeling by energy method and simulation of a wind turbine aided by computer. In this paper, the equations of motion are extracted for simulating the system of wind turbine and then the behavior of the system become obvious by solving the equations. The turbine is considered with three blade rotor in wind direction, induced generator that is connected to the network and constant revolution for simulation of wind turbine. Every part of the wind turbine should be simulated for simulation of wind turbine. The main parts are blades, gearbox, shafts and generator

Pole-mounted horizontal axis micro-wind turbines: UK field trial findings and market size assessment

International Nuclear Information System (INIS)

Sissons, M.F.; James, P.A.B.; Bradford, J.; Myers, L.E.; Bahaj, A.S.; Anwar, A.; Green, S.

2011-01-01

This paper discusses the key findings of the pole-mounted turbine (2.5-6 kWp) component of the UK micro-wind trial. The real world performance of horizontal axis turbines is compared with yield estimates based on site wind speed prediction. The distribution of UK agricultural farms is overlaid with wind resource mapping to estimate the number of potential agricultural farm sites for micro-wind. The yield performance of turbines during the monitoring period was observed to be very close to that predicted by NOABL-MCS wind speed estimates. Based on an installation criterion of a maximum 12 year payback time, with a 6% discount rate and micro-generation feed in tariffs available, there are ∼87,000 farm sites for micro-wind in the UK. If 10% of these farms were to install micro-wind turbines (to a capacity of 48 kWp per farm) this would correspond to a capacity of 418 MWp, with an annual generation yield of 1025 GWh, comparable to that of a large, on shore wind farm in the UK. It should be noted that the feed in tariff considered in this paper is that available in the UK in 2011, which, at 26.7 p/kWh (∼30 Euro cents/kWh) represents a significant subsidy. - Highlights: → Estimated 87,000 agricultural farm sites which are economic for pole mounted micro-wind in the UK. → Good agreement between NOABL-MCS yield prediction and site measurements for UK pole mounted turbines. → Pole mounted micro-wind has favourable economics under current UK feed in tariffs.

Aerodynamic study of a small wind turbine with emphasis on laminar and transition flows

Science.gov (United States)

Niculescu, M. L.; Cojocaru, M. G.; Crunteanu, D. E.

2016-06-01

The wind energy is huge but unfortunately, wind turbines capture only a little part of this enormous green energy. Furthermore, it is impossible to put multi megawatt wind turbines in the cities because they generate a lot of noise and discomfort. Instead, it is possible to install small Darrieus and horizontal-axis wind turbines with low tip speed ratios in order to mitigate the noise as much as possible. Unfortunately, the flow around this wind turbine is quite complex because the run at low Reynolds numbers. Therefore, this flow is usually a mixture of laminar, transition and laminar regimes with bubble laminar separation that is very difficult to simulate from the numerical point of view. Usually, transition and laminar regimes with bubble laminar separation are ignored. For this reason, this paper deals with laminar and transition flows in order to provide some brightness in this field.

The application of suction caisson technology to offshore wind turbines

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-09-15

A mathematical model describing the behaviour of caisson foundations for offshore wind turbines has been developed. The model has been verified and calibrated through laboratory and field work. Simultaneously, conceptual designs of wind turbine foundations incorporating suction caissons were studied using the same model. It was concluded that much of the seabed around Britain is well suited to the use of caissons and monopod and quadropod structures are superior to tripods. Although suction caissons are vulnerable to scour, rock dumping can largely eliminate this potential problem. The next phase will be to install a fully instrumented full-scale prototype to monitor the effects of wind and waves. The main contractor was SLP Engineering Limited and about 75 per cent of the funding came from the DTI.

Wind Turbine Radar Cross Section

Directory of Open Access Journals (Sweden)

David Jenn

2012-01-01

Full Text Available The radar cross section (RCS of a wind turbine is a figure of merit for assessing its effect on the performance of electronic systems. In this paper, the fundamental equations for estimating the wind turbine clutter signal in radar and communication systems are presented. Methods of RCS prediction are summarized, citing their advantages and disadvantages. Bistatic and monostatic RCS patterns for two wind turbine configurations, a horizontal axis three-blade design and a vertical axis helical design, are shown. The unique electromagnetic scattering features, the effect of materials, and methods of mitigating wind turbine clutter are also discussed.

Hybrid damper with stroke amplification for damping of offshore wind turbines

DEFF Research Database (Denmark)

Brodersen, Mark L.; Høgsberg, Jan

2016-01-01

tower. The proposed hybrid damper consists of a passive viscous dashpot placed in series with a load cell and an active actuator. By integrated force feedback control of the actuator motion, the associated displacement amplitude over the viscous damper can be increased compared with the passive viscous......The magnitude of tower vibrations of offshore wind turbines is a key design driver for the feasibility of the monopilesupport structure. A novel control concept for the damping of these tower vibrations is proposed, where viscous-type hybrid dampers are installed at the bottom of the wind turbine...... case, hereby significantly increasing the feasibility of viscous dampers acting at the bottom of the wind turbine tower. To avoid drift in the actuator displacement, a filtered time integration of the measured force signal is introduced. Numerical examples demonstrate that the filtered time integration...

Numerical simulation on a straight-bladed vertical axis wind turbine with auxiliary blade

Science.gov (United States)

Li, Y.; Zheng, Y. F.; Feng, F.; He, Q. B.; Wang, N. X.

2016-08-01

To improve the starting performance of the straight-bladed vertical axis wind turbine (SB-VAWT) at low wind speed, and the output characteristics at high wind speed, a flexible, scalable auxiliary vane mechanism was designed and installed into the rotor of SB-VAWT in this study. This new vertical axis wind turbine is a kind of lift-to-drag combination wind turbine. The flexible blade expanded, and the driving force of the wind turbines comes mainly from drag at low rotational speed. On the other hand, the flexible blade is retracted at higher speed, and the driving force is primarily from a lift. To research the effects of the flexible, scalable auxiliary module on the performance of SB-VAWT and to find its best parameters, the computational fluid dynamics (CFD) numerical calculation was carried out. The calculation result shows that the flexible, scalable blades can automatic expand and retract with the rotational speed. The moment coefficient at low tip speed ratio increased substantially. Meanwhile, the moment coefficient has also been improved at high tip speed ratios in certain ranges.

Wind Turbine Generator Efficiency Based on Powertrain Combination and Annual Power Generation Prediction

Directory of Open Access Journals (Sweden)

Dongmyung Kim

2018-05-01

Full Text Available Wind turbine generators are eco-friendly generators that produce electric energy using wind energy. In this study, wind turbine generator efficiency is examined using a powertrain combination and annual power generation prediction, by employing an analysis model. Performance testing was conducted in order to analyze the efficiency of a hydraulic pump and a motor, which are key components, and so as to verify the analysis model. The annual wind speed occurrence frequency for the expected installation areas was used to predict the annual power generation of the wind turbine generators. It was found that the parallel combination of the induction motors exhibited a higher efficiency when the wind speed was low and the serial combination showed higher efficiency when wind speed was high. The results of predicting the annual power generation considering the regional characteristics showed that the power generation was the highest when the hydraulic motors were designed in parallel and the induction motors were designed in series.

Development of wind turbines for safe operation in alpine environments - Annual report

Energy Technology Data Exchange (ETDEWEB)

Barber, S.; Abhari, R.

2009-08-15

Many favourable sites for wind farms, particularly in the Swiss Alps, are located in cold, wet regions where the build-up of ice is a risk and therefore limits the installation of wind turbines. The aim of this work is to quantify and understand in detail the effects of blade icing on wind turbine performance and to propose mitigation strategies. The project is unique in that it is carried out using a multi-disciplinary approach that combines (1) analysis of field data, (2) controlled experiments on a sub-scale wind turbine model and (3) 3D Computational Fluid Dynamics. In part (1) the wind data and full-scale wind turbine power and icing measurements from the Alpine Test Site Guetsch over one year are analysed. Icing on the blades is estimated to cause approximately a 2% loss in Annual Energy Production (AEP). Other losses due to the particular location of the turbine in complex terrain are found to reduce the expected AEP by up to 23%. These major losses must be further investigated in controlled experiments. The analysis of photographs of ice on the blades, alongside numerical simulations, enables five ice geometries to be defined for Guetsch atmospheric conditions (altitude: 2331 m above sea level). One further 'extreme' ice shape is also defined, which is representative of ice formed on wind turbines installed at lower altitude sites such as the Berne Jura (altitude: 800 to 1500 m). In part (2), experiments are undertaken in the new sub-scale wind turbine test facility at ETH Zuerich using a novel method to quantify performance. The defined ice shapes are attached to the blades and the performance compared. The five shapes representative of the ice formed at Guetsch are found to reduce the Annual Energy Production by up to 2%. However, the 'extreme' ice shape could result in a loss in Annual Energy Production of up to 17%. Furthermore, the presence of ice on the most outboard 5% of the blade is found to be key to performance. Ice removal or

The design of wind turbine for electrical power generation in Malaysian wind characteristics

International Nuclear Information System (INIS)

Abas Ab Wahab; Chong Wen Thong

2000-01-01

The paper describes the study of a wind turbine for electrical power generation in Malaysia wind characteristics. In this research, the wind turbine is designs based on the local wind characteristics and tries to avoid the problems faced in the past (turbine design, access, manpower and technical). The new wind turbine rotor design for a medium speed wind speed turbine utilises the concept of open-close type of horizontal axis (up-wind) wind turbine is intended to widen the optimum performance range for electrical generation in Malaysia wind characteristics. The wind turbine has been designed to cut-in at a lower speed, and to provide the rotation speed that high enough to run a generator. The analysis and design of new low speed wind turbine blades and open-close turbine rotor and prediction of turbine performance are being detailed in this paper. (Author)

Investigation of Wind Turbine Rotor Concepts for Offshore Wind Farms

International Nuclear Information System (INIS)

Ceyhan, Özlem; Grasso, Francesco

2014-01-01

Current plans in offshore wind energy developments call for further reduction of cost of energy. In order to contribute to this goal, several wind turbine rotor concepts have been investigated. Assuming the future offshore wind turbines will operate only in the offshore wind farms, the rotor concepts are not only evaluated for their stand-alone performances and their potential in reducing the loads, but also for their performance in an offshore wind farm. In order to do that, the 10MW reference wind turbine designed in Innwind.EU project is chosen as baseline. Several rotor parameters have been modified and their influences are investigated for offshore wind turbine design purposes. This investigation is carried out as a conceptual parametrical study. All concepts are evaluated numerically with BOT (Blade optimisation tool) software in wind turbine level and with Farmflow software in wind farm level for two wind farm layouts. At the end, all these concepts are compared with each other in terms of their advantages and disadvantages

Noise emission from wind turbines in wake. Project report

Energy Technology Data Exchange (ETDEWEB)

Dam Madsen, K.; Plovsing, B. (DELTA, Hoersholm (Denmark)); Soerensen, Thomas (EMD International A/S, Aalborg (Denmark)); Aagaard Madsen, H.; Bertagnolio, F. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark))

2011-03-15

When installing wind turbines in clusters or wind farms the inflow conditions to the wind turbines can be disturbed due to wake effects from other wind turbines. The effect of wake on noise generation from wind turbines are described in this report. The work is based on measurements carried out on a M80 2 MW wind turbine. To investigate the relationship between the far field noise levels and the surface pressure and inflow angles measured by sensors on an instrumented wind turbine blade, a parabolic measurement system (PMMS) was designed and tested as part of this project. Based on the measurement results obtained with surface pressure sensors and results from the far field measurements using the PMMS it is concluded that: The variance of surface pressure at the trailing edge (TE) agrees with the theory with regard to variation of pressure spectra with varying inflow angle (AoA) to the blade. Low frequency TE surface pressure increases with increased AoA and high frequency surface pressure decreases with increased AoA. It seems that the TE surface pressure remains almost unaltered during wake operation. Results from the surface transducers at the leading edge (LE) and the inflow angles determined from the pitot tube indicates that the inflow at LE is more turbulent in wake for the same AoA and with a low frequency characteristic, thereby giving rise to more low frequency noise generated during wake operation. The far field measurements supports that on one hand there will be produced relative more low frequency noise due to a turbulent inflow to the blade and on the other hand there will be produced less noise in the broader frequency range/high frequency range due to a lower inflow angle caused by the wind deficit in the wake. The net effect of wake on the total noise level is unresolved. As a secondary result it is seen that noise observed from a position on the ground is related to directional effects of the noise radiated from the wind turbine blade. For an

Intention to respond to local wind turbines: the role of attitudes and visual perception

Energy Technology Data Exchange (ETDEWEB)

Johansson, Maria; Laike, Thorbjorn [Environmental Psychology Unit, Department of Architecture and the Built Environment, Lund University, PO Box 118, SE-221 00 Lund, (Sweden)

2007-06-21

Wind power projects frequently face public opposition during the siting process. A deeper understanding of social factors has therefore been called for. Based on psychological theories, the present research was initiated in order to study the relative importance of individual aspects related to visual perception and attitudinal factors in public intention to oppose local wind turbines. In an empirical study, 80 people assessed the visual characteristics of wind turbines on site and rated their emotional state. They also completed a questionnaire covering attitudes towards the turbines, perception of significant others' opinions of local wind turbines, and perceived possibilities to oppose as well as intention to oppose local turbines. Moreover, socio-demographics, factors related to the place of residence and general attitude towards wind power, were investigated. In a multiple regression analysis explaining 50% of the variance, it was found that intention to oppose was related to only a few perceptual and attitudinal factors, i.e. the perceived unity of the environment, the personal attitude towards the effects of wind turbines on landscape aesthetics and recreation, and the general attitude towards wind power. Of minor importance was the attitude towards the effects of wind turbines on people's daily quality of life. It seems important to involve the public in the discussion of how wind power installations can be integrated into the landscape without threatening the visual beauty and the recreational value of the natural and cultural environment. Moreover, social intervention is required to promote positive attitudes towards wind turbines. (Author).

Wind turbine optimal control during storms

International Nuclear Information System (INIS)

Petrović, V; Bottasso, C L

2014-01-01

This paper proposes a control algorithm that enables wind turbine operation in high winds. With this objective, an online optimization procedure is formulated that, based on the wind turbine state, estimates those extremal wind speed variations that would produce maximal allowable wind turbine loads. Optimization results are compared to the actual wind speed and, if there is a danger of excessive loading, the wind turbine power reference is adjusted to ensure that loads stay within allowed limits. This way, the machine can operate safely even above the cut-out wind speed, thereby realizing a soft envelope-protecting cut-out. The proposed control strategy is tested and verified using a high-fidelity aeroservoelastic simulation model

Effect of Coupled Non linear Wave Kinematics and Soil Flexibility on the Design Loads of Offshore Wind Turbines

DEFF Research Database (Denmark)

Kim, Taeseong; Natarajan, Anand

2013-01-01

The design driving loads on offshore wind turbine monopile support structures at water depths of 35m, which are beyond current monopile installation depths, are derived based on fully coupled aerohydroelastic simulations of the wind turbine in normal operation and in storm conditions in the prese...

The department Charter of the Finistere wind turbines; La charte departementale des eoliennes du Finistere

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-06-01

In a context favorable to the renewable energies development, the Finistere showed in few months many wind turbines installation projects. Those projects present conflicting stakes: the richest areas in terms of energy are also the most sensitive in term of ecology and environment. The conciliation of these conflicting stakes is difficult because the town planning documents do not take into account these installations specificities. Therefore the Finistere decided to write a department charter for the wind turbines. The first chapter deals with the objectives and the partners engagements, the second chapter presents elements of decision making. (A.L.B.)

Bat mortality due to collision with wind turbines in Kutch District, Gujarat, India

Directory of Open Access Journals (Sweden)

S.R. Kumar

2013-09-01

Full Text Available Globally, India is at fifth position in wind power generation with an installed capacity of 14550 MW. Based onrecent reports from certain parts of the world there is also a growing concern on the environmental impact of wind turbines on bats and birds in other places too. In the Indian context the impact of wind farms on birds and bats are less studied with very little scientific literature available on the subject. Since September 2011, we have been conducting research on birds and bats mortality in wind farms of Kutch District, Gujarat, India. During the study period two carcasses of the Greater Mouse-tailed Bat Rhinopoma microphyllum were recorded due to collision with wind turbines.

Wind Turbine Fault Detection based on Artificial Neural Network Analysis of SCADA Data

DEFF Research Database (Denmark)

Herp, Jürgen; S. Nadimi, Esmaeil

2015-01-01

Slowly developing faults in wind turbine can, when not detected and fixed on time, cause severe damage and downtime. We are proposing a fault detection method based on Artificial Neural Networks (ANN) and the recordings from Supervisory Control and Data Acquisition (SCADA) systems installed in wind...

Megawatt wind turbines gaining momentum

International Nuclear Information System (INIS)

Oehlenschlaeger, K.; Madsen, B.T.

1996-01-01

Through the short history of the modern wind turbine, electric utilities have made it amply clear that they have held a preference for large scale wind turbines over smaller ones, which is why wind turbine builders through the years have made numerous attempts develop such machines - machines that would meet the technical, aesthetic and economic demands that a customer would require. Considerable effort was put into developing such wind turbines in the early 1980s. There was the U.S. Department of Energy's MOD 1-5 program, which ranged up to 3.2 MW, Denmark's Nibe A and B, 630 kW turbine and the 2 MW Tjaereborg machine, Sweden's Naesudden, 3 MW, and Germany's Growian, 3 MW. Most of these were dismal failures, though some did show the potential of MW technology. (au)

Condition monitoring of a wind turbine doubly-fed induction generator through current signature analysis

Science.gov (United States)

Artigao, Estefania; Honrubia-Escribano, Andres; Gomez-Lazaro, Emilio

2017-11-01

Operation and maintenance (O&M) of wind turbines is recently becoming the spotlight in the wind energy sector. While wind turbine power capacities continue to increase and new offshore developments are being installed, O&M costs keep raising. With the objective of reducing such costs, the new trends are moving from corrective and preventive maintenance toward predictive actions. In this scenario, condition monitoring (CM) has been identified as the key to achieve this goal. The induction generator of a wind turbine is a major contributor to failure rates and downtime where doubly-fed induction generators (DFIG) are the dominant technology employed in variable speed wind turbines. The current work presents the analysis of an in-service DFIG. A one-year measurement campaign has been used to perform the study. Several signal processing techniques have been applied and the optimal method for CM has been identified. A diagnosis has been reached, the DFIG under study shows potential gearbox damage.

Design and fabrication of a low cost Darrieus vertical axis wind turbine system: Phase 2, volume 1: Executive summary

Science.gov (United States)

1983-03-01

Described is the successful fabrication, installation, and checkout of 100 kW 17 meter Vertical Axis Wind Turbines (VAWTs). The turbines are Darrieus-type VAWTs with rotors 17 meters (55 feet) in diameter and 25.15 meters (83 feet) in height. They can produce 100 kW of electric power at a cost of energy as low as 3 cents per kWh, in an 18 mph wind regime using 12% annualized costs. Four turbines were produced; three are installed and are operable at: (1) Wind Systems Test Center, Rocky Flats, Colorado; (2) the US Department of Agriculture Conservation and Production Research Center at Bushland, Texas; and (3) Tisbury Water Authority, Vineyard Haven, Massachusetts, on the island of Martha's Vineyard. The fourth turbine is stored at Bushland, Texas awaiting selection of an erection site.

Grid support capabilities of wind turbines

DEFF Research Database (Denmark)

Michalke, Gabriele; Hansen, Anca Daniela

2013-01-01

Wind power has gained a significant penetration level in several power systems all over the world. Due to this reason modern wind turbines are requested to contribute to power system support. Power system operators have thus introduced grid codes, which specify a set of requirements for wind...... turbines, such as fault ride-through and reactive power supply during voltage sags. To date different wind turbine concepts exist on the market comprising different control features in order to provide ancillary services to the power system. In the first place the present chapter emphasizes the most...... important issues related to wind power grid integration. Then different wind turbine concepts are characterized and their grid support capabilities are analysed and compared. Simulation cases are presented in which the respective wind turbine concepts are subjected to a voltage dip specified in a grid code....

Wind Resource Assessment and Requested Wind Turbine Recommendations

Energy Technology Data Exchange (ETDEWEB)

Smith, Ken [Municipal Civil Corporation, Gas City, IN (United States); Wolar, John [Municipal Civil Corporation, Gas City, IN (United States)

2012-10-22

Alternate Energy Solutions, Inc. (“AESWR”) was engaged by the Town of Brookston (“Brookston”) to assemble, erect and maintain one 60 m XHD meteorological tower manufactured by NRG Systems, Inc.; for monitoring, recording and evaluating collected wind data. It is the opinion of AESWR staff that study results support the development of a wind turbine project at the Bol Family Farm provided: a) additional land is leased for the project; b) project construction costs are controlled; and c) a prudent power purchase agreement is negotiated with a power take-off entity. We believe that a project having an aggregate nameplate rating sized from 6.0 MW to 20 MW would be appropriate for this location. We recommend 100-125 acres of land per installed MW be used as a general rule for acquiring wind energy land lease agreements, total land lease holdings to be acquired would then approach 750 acres to 2,500 acres.

Wind Turbine Acoustic Day 2018

DEFF Research Database (Denmark)

Mogensen, Jesper; Søndergaard, Bo; Hünerbein, Sabine Von

The bi-annual event entitled Wind Turbine Acoustic Day dealing with wind turbine noise issues organized by DTU Wind Energy took place on May, 17th 2018 as its third edition. The abstracts and slides for the presentations are reported....

Structural Reliability Aspects in Design of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2007-01-01

Reliability assessment, optimal design and optimal operation and maintenance of wind turbines are an area of significant interest for the fast growing wind turbine industry for sustainable production of energy. Offshore wind turbines in wind farms give special problems due to wake effects inside...... the farm. Reliability analysis and optimization of wind turbines require that the special conditions for wind turbine operation are taken into account. Control of the blades implies load reductions for large wind speeds and parking for high wind speeds. In this paper basic structural failure modes for wind...... turbines are described. Further, aspects are presented related to reliability-based optimization of wind turbines, assessment of optimal reliability level and operation and maintenance....

The echo of the functioning of wind turbines on the man health

International Nuclear Information System (INIS)

2005-01-01

The noise is the most frequent complaint, irregular in intensity it perturbs the sleep. Wind turbines are made responsible for other subjective disorders such as:headaches, fatigue, temporary sensations of drunkenness, nausea and sometimes objective ones such as: vomits, insomnias, palpitations. The movements of the shade of pales in rotation were made responsible for absent-mindedness susceptible to bring car accidents, even epilepsy. The most important modification of the environment due to the functioning of wind turbines is as any industrial installation, the creation of vibrations of the ambient environment. A working group asked by the Academy of medicine to examine this question gives some recommendations: to realize a procedure to register on a period of several weeks, the noise induced by wind turbines in houses, to implement an epidemiology inquiry on the sanitary consequences of this noise on the populations, that will be correlated with the distance from these turbines; by waiting the results of these studies, the Academia recommends to suspend the construction of the wind turbines of a power superior to 2.5 MW situated unless 1500 m houses, to modify the article 98 of the law of the 2. july 2003 to consider the wind turbines as industrial facilities when they go over a chosen power and their setting-up are submitted to a regulation taking into account noise pollutions which they induce. (N.C.)

Wind Predictions Upstream Wind Turbines from a LiDAR Database

Directory of Open Access Journals (Sweden)

Soledad Le Clainche

2018-03-01

Full Text Available This article presents a new method to predict the wind velocity upstream a horizontal axis wind turbine from a set of light detection and ranging (LiDAR measurements. The method uses higher order dynamic mode decomposition (HODMD to construct a reduced order model (ROM that can be extrapolated in space. LiDAR measurements have been carried out upstream a wind turbine at six different planes perpendicular to the wind turbine axis. This new HODMD-based ROM predicts with high accuracy the wind velocity during a timespan of 24 h in a plane of measurements that is more than 225 m far away from the wind turbine. Moreover, the technique introduced is general and obtained with an almost negligible computational cost. This fact makes it possible to extend its application to both vertical axis wind turbines and real-time operation.

Assessing the responses of coastal cetaceans to the construction of offshore wind turbines.

Science.gov (United States)

Thompson, Paul M; Lusseau, David; Barton, Tim; Simmons, Dave; Rusin, Jan; Bailey, Helen

2010-08-01

The expansion of offshore renewables has raised concerns over potential disturbance to coastal cetaceans. In this study, we used passive acoustic monitoring to assess whether cetaceans responded to pile-driving noise during the installation of two 5MW offshore wind turbines off NE Scotland in 2006. Monitoring was carried out at both the turbine site and a control site in 2005, 2006 and 2007. Harbour porpoises occurred regularly around the turbine site in all years, but there was some evidence that porpoises did respond to disturbance from installation activities. We use these findings to highlight how uncertainty over cetacean distribution and the scale of disturbance effects constrains opportunities for B-A-C-I studies. We explore alternative approaches to assessing the impact of offshore wind farm upon cetaceans, and make recommendations for the research and monitoring that will be required to underpin future developments. Copyright 2010 Elsevier Ltd. All rights reserved.

Observation of high-resolution wind fields and offshore wind turbine wakes using TerraSAR-X imagery

Science.gov (United States)

Gies, Tobias; Jacobsen, Sven; Lehner, Susanne; Pleskachevsky, Andrey

2014-05-01

coast of Borkum, Germany, and consists of twelve 5-Megawatt wind power turbines. The retrieved results are validated by comparing with QuikSCAT measurements, the results of the German Weather Service (DWD) atmospheric model and in-situ measurements of wind speed and wind direction, obtained from the research platform FiNO1, installed 400 m west of Alpha Ventus. 4. Conclusion In the presented case study we quantify the wake characteristics of wake length, wake width, maximum velocity de?cit, wake merging and wake meandering. We show that SAR has the capability to map the sea surface two-dimensionally in high spatial resolution which provides a unique opportunity to observe spatial characteristics of offshore wind turbine wakes. The SAR derived information can support offshore wind farming with respect to optimal siting and design and help to estimate their effects on the environment.

Type IV Wind Turbine Model

DEFF Research Database (Denmark)

Hansen, Anca Daniela; Margaris, Ioannis D.

. In the project, this wind turbine model will be further incorporated in a wind power plant model together with the implementation in the wind power control level of the new control functionalities (inertial response, synchronising power and power system damping). For this purpose an aggregate wind power plant......This document is created as part of the EaseWind project. The goal of this project is to develop and investigate new control features for primary response provided by wind power plants. New control features as inertial response, synchronising power and power system damping are of interest to EaseWind...... project to be incorporated in the wind power plant level. This document describes the Type 4 wind turbine simulation model, implemented in the EaseWind project. The implemented wind turbine model is one of the initial necessary steps toward integrating new control services in the wind power plant level...

Modeling and control of a hybrid wind-tidal turbine with hydraulic accumulator

International Nuclear Information System (INIS)

Fan, YaJun; Mu, AnLe; Ma, Tao

2016-01-01

This paper presents the modeling and control of a hybrid wind-tidal turbine with hydraulic accumulator. The hybrid turbine captures the offshore wind energy and tidal current energy simultaneously and stores the excess energy in hydraulic accumulator prior to electricity generation. Two hydraulic pumps installed respectively in wind and tidal turbine nacelles are used to transform the captured mechanical energy into hydraulic energy. To extract the maximal power from wind and tidal current, standard torque controls are achieved by regulating the displacements of the hydraulic pumps. To meet the output power demand, a Proportion Integration Differentiation (PID) controller is designed to distribute the hydraulic energy between the accumulator and the Pelton turbine. A simulation case study based on combining a 5 MW offshore wind turbine and a 1 MW tidal current turbine is undertaken. Case study demonstrates that the hybrid generation system not only captures all the available wind and tidal energy and also delivers the desired generator power precisely through the accumulator damping out all the power fluctuations from the wind and tidal speed disturbances. Energy and exergy analyses show that the energy efficiency can exceed 100% as the small input speeds are considered, and the exergy efficiency has the consistent change trends with demand power. Further more parametric sensitivity study on hydraulic accumulator shows that there is an inversely proportional relationship between accumulator and hydraulic equipments including the pump and nozzle in terms of dimensions. - Highlights: • A hybrid wind-tidal turbine is presented. • Hydraulic accumulator stores/releases the surplus energy. • Standard torque controls extract the maximal power from wind and tidal. • Generator outputs meet the electricity demand precisely. • Parametric sensitivity study on accumulator is implemented.

Construction of low-cost, Mod-OA wood composite wind turbine blades

Science.gov (United States)

Lark, R. F.

1983-01-01

Two sixty-foot, low-cost, wood composite blades for service on 200 kW Mod-OA wind turbines were constructed. The blades were constructed of epoxy resin-bonded Douglas fir veneers for the leading edge sections, and paper honeycombcored, birch plywood faced panels for the afterbody sections. The blades were joined to the wind turbine hub by epoxy resin-bonded steel load take-off studs embedded into the root end of the blades. The blades were installed on the 200 kW Mod-OA wind turbine facility at Kahuku, Hawaii, The blades completed nearly 8,000 hours of operation over an 18 month period at an average power of 150 kW prior to replacement with another set of wood composite blades. The blades were replaced because of a corrosion failure of the steel shank on one stud. Inspections showed that the wood composite structure remained in excellent condition.

Compare. An analysis of jurisprudence of the Dutch Real Estate Appraisal in relation with the vicinity of wind turbines

International Nuclear Information System (INIS)

Berenschot, J.H.M.

2005-11-01

The central question in this report concerns the impact of recent judgements with regard to the devaluation of houses as a result of wind turbines in the vicinity of those houses. More specific: does the installation of wind turbines near houses effect the so-called Real Estate Appraisal tax for those houses. From four cases it appears that three aspects are important: noise pollution, cast shadow hindrance and visual hindrance, caused by wind turbines [nl

Wind power production: from the characterisation of the wind resource to wind turbine technologies

International Nuclear Information System (INIS)

Beslin, Guy; Multon, Bernard

2016-01-01

Illustrated by graphs and tables, this article first describes the various factors and means related to the assessment of wind resource in the World, in Europe, and the factors which characterize a local wind resource. In this last respect, the authors indicate how local topography is taken into account to calculate wind speed, how time variations are taken into account (at the yearly, seasonal or daily level), the different methods used to model a local wind resource, how to assess the power recoverable by a wind turbine with horizontal axis (notion of Betz limit). In the second part, the authors present the different wind turbines, their benefits and drawbacks: vertical axis, horizontal axis (examples of a Danish-type wind turbine, of wind turbines designed for extreme conditions). Then, they address the technology of big wind turbines: evolution of technology and of commercial offer, aerodynamic characteristics of wind turbine and benefit of a varying speed (technological solutions, importance of the electric generator). They describe how to choose a wind turbine, how product lines are organised, how the power curve and energy capacity are determined. The issue of integration of wind energy into the power system is then addressed. The next part addressed the economy of wind energy production (annualized production cost, order of magnitude of wind electric power production cost). Future trends are discussed and offshore wind energy production is briefly addressed

Magnetic Geared Radial Axis Vertical Wind Turbine for Low Velocity Regimes

Directory of Open Access Journals (Sweden)

Wei Wei Teow

2018-01-01

Full Text Available In the 21st century, every country is seeking an alternative source of energy especially the renewable sources. There are considerable developments in the wind energy technology in recent years and in more particular on the vertical axis wind turbine (VAWT as they are modular, less installation cost and portable in comparison with that of the horizontal axis wind turbine (HAWT systems. The cut-in speed of a conventional wind turbine is 3.5 m/s to 5 m/s. Mechanical geared generators are commonly found in wind technology to step up power conversion to accommodate the needs of the generator. Wind turbine gearboxes suffer from overload problem and frequent maintenance in spite of the high torque density produced. However, an emerging alternative to gearing system is Magnetic Gear (MG as it offers significant advantages such as free from maintenance and inherent overload protection. In this project, numerical analysis is done on designed magnetic gear greatly affects the performance of the generator in terms of voltage generation. Magnetic flux density is distributed evenly across the generator as seen from the uniform sinusoidal output waveform. Consequently, the interaction of the magnetic flux of the permanent magnets has shown no disturbance to the output of the generator as the voltage generated shows uniform waveform despite the rotational speed of the gears. The simulation is run at low wind speed and the results show that the generator starts generating a voltage of 240 V at a wind speed of 1.04 m/s. This shows great improvement in the operating capability of the wind turbine.

Controls of Hydraulic Wind Turbine

Directory of Open Access Journals (Sweden)

Zhang Yin

2016-01-01

Full Text Available In this paper a hydraulic wind turbine generator system was proposed based on analysis the current wind turbines technologies. The construction and principles were introduced. The mathematical model was verified using MATLAB and AMsim. A displacement closed loop of swash plate of motor and a speed closed loop of generator were setup, a PID control is introduced to maintain a constant speed and fixed frequency at wind turbine generator. Simulation and experiment demonstrated that the system can connect grid to generate electric and enhance reliability. The control system demonstrates a high performance speed regulation and effectiveness. The results are great significant to design a new type hydraulic wind turbine system.

Probabilistic Design of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Toft, H.S.

2010-01-01

Probabilistic design of wind turbines requires definition of the structural elements to be included in the probabilistic basis: e.g., blades, tower, foundation; identification of important failure modes; careful stochastic modeling of the uncertain parameters; recommendations for target reliability....... It is described how uncertainties in wind turbine design related to computational models, statistical data from test specimens, results from a few full-scale tests and from prototype wind turbines can be accounted for using the Maximum Likelihood Method and a Bayesian approach. Assessment of the optimal...... reliability level by cost-benefit optimization is illustrated by an offshore wind turbine example. Uncertainty modeling is illustrated by an example where physical, statistical and model uncertainties are estimated....

Wind Turbine Generator System Safety and Function Test Report for the Entegrity EW50 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Smith, J.; Huskey, A.; Jager, D.; Hur, J.

2012-11-01

This report summarizes the results of a safety and function test that NREL conducted on the Entegrity EW50 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

Advances in wind turbine blade design and materials

DEFF Research Database (Denmark)

Wind energy is gaining critical ground in the area of renewable energy, with wind energy being predicted to provide up to 8% of the world’s consumption of electricity by 2021. Advances in wind turbine blade design and materials reviews the design and functionality of wind turbine rotor blades...... as well as the requirements and challenges for composite materials used in both current and future designs of wind turbine blades. Part one outlines the challenges and developments in wind turbine blade design, including aerodynamic and aeroelastic design features, fatigue loads on wind turbine blades......, and characteristics of wind turbine blade airfoils. Part two discusses the fatigue behavior of composite wind turbine blades, including the micromechanical modelling and fatigue life prediction of wind turbine blade composite materials, and the effects of resin and reinforcement variations on the fatigue resistance...

Wind turbine improvements by wind-lidar-based preview and control

DEFF Research Database (Denmark)

Mikkelsen, Torben

2014-01-01

Wind turbines equipped with laser prevision hold potential for up to 6+ years lifetime extension. Forward looking wind lidars integrated within operational wind turbines providing feed-forward control can reduce the daily operation loads. The turbine lifetime may in this way be extended by up to 30...

Occupational Health and Industrial Wind Turbines: A Case Study

Science.gov (United States)

Rand, Robert W.; Ambrose, Stephen E.; Krogh, Carmen M. E.

2011-01-01

Industrial wind turbines (IWTs) are being installed at a fast pace globally. Researchers, medical practitioners, and media have reported adverse health effects resulting from living in the environs of IWTs. While there have been some anecdotal reports from technicians and other workers who work in the environs of IWTs, little is known about the…

Small power wind turbine (Type DARRIEUS

Directory of Open Access Journals (Sweden)

Marcel STERE

2012-03-01

Full Text Available This presentation focuses on the calculation for small vertical axis wind turbines (VAWT for an urban application. The fixed-pitch straight – bladed vertical axis wind turbine (SB-VAWT is one of the simplest types of wind turbine and accepts wind from any angle (no yaw system. This turbine is useful for moderate wind speeds (3 - 6 m/s. A case study is presented based upon the use of well documented symmetrical NACA 0012 turbine blade profile. We describe a solution for VAWT. To perform a linear static analysis in the structure, the commercial finite element analysis code ANSYS is used because of its flexibility for handling information in files written in a more or less free format.

Monitoring and economics of a 60 kW wind turbine generator on a pig farm in Scotland

International Nuclear Information System (INIS)

Saluja, G.S.

1990-01-01

Low cost monitoring of a 60 kW wind turbine generator connected to an intensive pig farm in the Grampian area of Scotland is described. A method of calculating the economic implications of installing a small grid-connected wind turbine generator at a farm is based on monitored data, electricity bills and energy production is proposed. (author)

Noise from wind turbines

International Nuclear Information System (INIS)

Andersen, B.; Jakobsen, J.

1992-11-01

Based on a previous project concerning the calculation of the amount of noise emanating from wind turbine arrays, this one examines the subject further by investigating whether there could be significant differences in the amount of noise made by individual wind turbines in an array, and whether the noise is transmitted in varying directions - so that when it is carried in the same direction as the wind blows it would appear to be louder. The aim was also to determine whether the previously used method of calculation lacked precision. It was found that differences in noise niveaux related to individual wind turbines were insignificant and that noise was not so loud when it was not borne in the direction of the wind. It was necessary to change the method of calculation as reckoning should include the influence of the terrain, wind velocity and distance. The measuring and calculation methods are exemplified and the resulting measurements are presented in detail. (AB)

Danish wind turbines: Technical-economic feasibility of commercial models

International Nuclear Information System (INIS)

Falchetta, M.

1992-01-01

This feasibility study examines the principal technical and economic (investment-manufacturing-installation-operation unit costs, supply and demand) characteristics of wind turbines being commercialized in Denmark. The general configuration of the 150 to 450 kW range machines currently being manufactured can be described as that of a three bladed fibreglass rotor, of from 24 to 35 meters in diameter, and mounted on a tower of from 29 to 41 meters in height. The electrical system consists of one asynchronous generator or a two generator system with a power ratio of 1 to 5 between the two generators. The cost analysis reveals that the Danish wind turbines are competitively priced, with per kWh costs varying from $0. 0675 to $0. 040 for operating wind speeds ranging from 5 to 7 m/sec, and that their overall design and performance characteristics make them suitable for Italian site conditions

Wind speed reductions by large-scale wind turbine deployments lower turbine efficiencies and set low wind power potentials

Science.gov (United States)

Miller, Lee; Kleidon, Axel

2017-04-01

Wind turbines generate electricity by removing kinetic energy from the atmosphere. Large numbers of wind turbines are likely to reduce wind speeds, which lowers estimates of electricity generation from what would be presumed from unaffected conditions. Here, we test how well wind power potentials that account for this effect can be estimated without explicitly simulating atmospheric dynamics. We first use simulations with an atmospheric general circulation model (GCM) that explicitly simulates the effects of wind turbines to derive wind power limits (GCM estimate), and compare them to a simple approach derived from the climatological conditions without turbines [vertical kinetic energy (VKE) estimate]. On land, we find strong agreement between the VKE and GCM estimates with respect to electricity generation rates (0.32 and 0.37 We m-2) and wind speed reductions by 42 and 44%. Over ocean, the GCM estimate is about twice the VKE estimate (0.59 and 0.29 We m-2) and yet with comparable wind speed reductions (50 and 42%). We then show that this bias can be corrected by modifying the downward momentum flux to the surface. Thus, large-scale limits to wind power can be derived from climatological conditions without explicitly simulating atmospheric dynamics. Consistent with the GCM simulations, the approach estimates that only comparatively few land areas are suitable to generate more than 1 We m-2 of electricity and that larger deployment scales are likely to reduce the expected electricity generation rate of each turbine. We conclude that these atmospheric effects are relevant for planning the future expansion of wind power.

On the Fatigue Analysis of Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

Sutherland, Herbert J.

1999-06-01

Modern wind turbines are fatigue critical machines that are typically used to produce electrical power from the wind. Operational experiences with these large rotating machines indicated that their components (primarily blades and blade joints) were failing at unexpectedly high rates, which led the wind turbine community to develop fatigue analysis capabilities for wind turbines. Our ability to analyze the fatigue behavior of wind turbine components has matured to the point that the prediction of service lifetime is becoming an essential part of the design process. In this review paper, I summarize the technology and describe the ''best practices'' for the fatigue analysis of a wind turbine component. The paper focuses on U.S. technology, but cites European references that provide important insights into the fatigue analysis of wind turbines.

Modular Approach for the Optimal Wind Turbine Micro Siting Problem through CMA-ES Algorithm (abstract)

NARCIS (Netherlands)

Rodrigues, S.; Bauer, P.; Pierik, J.

2013-01-01

Although, only in recent years, northern European countries started to install large offshore wind farms, it is expected that by 2020, several dozens of far and large offshore wind farms (FLOWFs) will be built. These FLOWFs will be constituted of a considerable amount of wind turbines (WTs) packed

Market for wind turbines in italy

International Nuclear Information System (INIS)

1997-01-01

Wind power utilization in Italy has not been very popular until the privatization of the ENEL and introduction of subsidies for private electricity producers. The greatest interest is concentrated around large wind turbines. Therefore the Danish manufacturers with know-how within large wind turbines can establish themselves on the Italian market. Cooperation with one of the four local wind turbine manufacturers is advisable. (EG)

Wind lens technology and its application to wind and water turbine and beyond

Directory of Open Access Journals (Sweden)

Ohya Yuji

2017-01-01

Full Text Available Wind lens is a new type of wind power system consisting of a simple brimmed ring structure that surrounds the rotor causing greater wind to pass through the turbine. As a consequence, the turbine's efficiency of capturing energy from the wind gets dramatically increased. A Wind lens turbine can generate 2–5 times the power of an existing wind turbine given at the same rotor diameter and incoming wind speed. This fluid dynamical effect is also effective in the water. We have developed 1–3 kW Wind lens turbines and a 100 kW Wind lens turbine. In addition to the enhanced output power, Wind lens turbine is quiet. The technology is now used in an offshore experiment with a hexagonal float 18 meters in diameter set off the coast of Hakata Bay in Fukuoka City. Moreover, we are now pursuing larger size Wind lens turbines through multi-rotor design consisting of multiple Wind lens turbines in a same vertical plane to embody larger total power output.

Prognostics and Health Management of Wind Turbines: Current Status and Future Opportunities

Energy Technology Data Exchange (ETDEWEB)

Sheng, Shuangwen

2015-12-14

Prognostics and health management is not a new concept. It has been used in relatively mature industries, such as aviation and electronics, to help improve operation and maintenance (O&M) practices. In the wind industry, prognostics and health management is relatively new. The level for both wind industry applications and research and development (R&D) has increased in recent years because of its potential for reducing O&M cost of wind power, especially for turbines installed offshore. The majority of wind industry application efforts has been focused on diagnosis based on various sensing and feature extraction techniques. For R&D, activities are being conducted in almost all areas of a typical prognostics and health management framework (i.e., sensing, data collection, feature extraction, diagnosis, prognosis, and maintenance scheduling). This presentation provides an overview of the current status of wind turbine prognostics and health management that focuses on drivetrain condition monitoring through vibration, oil debris, and oil condition analysis techniques. It also discusses turbine component health diagnosis through data mining and modeling based on supervisory control and data acquisition system data. Finally, it provides a brief survey of R&D activities for wind turbine prognostics and health management, along with future opportunities.

Mitigating the negative impacts of tall wind turbines on bats: Vertical activity profiles and relationships to wind speed.

Science.gov (United States)

Wellig, Sascha D; Nusslé, Sébastien; Miltner, Daniela; Kohle, Oliver; Glaizot, Olivier; Braunisch, Veronika; Obrist, Martin K; Arlettaz, Raphaël

2018-01-01

Wind turbines represent a source of hazard for bats, especially through collision with rotor blades. With increasing technical development, tall turbines (rotor-swept zone 50-150 m above ground level) are becoming widespread, yet we lack quantitative information about species active at these heights, which impedes proposing targeted mitigation recommendations for bat-friendly turbine operation. We investigated vertical activity profiles of a bat assemblage, and their relationships to wind speed, within a major valley of the European Alps where tall wind turbines are being deployed. To monitor bat activity we installed automatic recorders at sequentially increasing heights from ground level up to 65 m, with the goal to determine species-specific vertical activity profiles and to link them to wind speed. Bat call sequences were analysed with an automatic algorithm, paying particular attention to mouse-eared bats (Myotis myotis and Myotis blythii) and the European free-tailed bat (Tadarida teniotis), three locally rare species. The most often recorded bats were the Common pipistrelle (Pipistrellus pipistrellus) and Savi's pipistrelle (Hypsugo savii). Mouse-eared bats were rarely recorded, and mostly just above ground, appearing out of risk of collision. T. teniotis had a more evenly distributed vertical activity profile, often being active at rotor level, but its activity at that height ceased above 5 ms-1 wind speed. Overall bat activity in the rotor-swept zone declined with increasing wind speed, dropping below 5% above 5.4 ms-1. Collision risk could be drastically reduced if nocturnal operation of tall wind turbines would be restricted to wind speeds above 5 ms-1. Such measure should be implemented year-round because T. teniotis remains active in winter. This operational restriction is likely to cause only small energy production losses at these tall wind turbines, although further analyses are needed to assess these losses precisely.

Noise annoyance from wind turbines a review

International Nuclear Information System (INIS)

Pedersen, Eja

2003-08-01

This study summarises present knowledge on noise perception and annoyances from wind turbines in areas were people live or spend recreation time. There are two main types of noise from a wind turbine: mechanical noise and aerodynamic noise. The aerodynamic noise emits from the rotor blades passing the air. It has a swishing character with a modulation that makes it noticeable from the background noise. This part of the wind turbine noise was found to be the most annoying. Field studies performed among people living in the vicinity of wind turbines showed that there was a correlation between sound pressure level and noise annoyance, but annoyance was also influenced by visual factors such as the attitude to wind turbines' impact on the landscape. Noise annoyance was found at lower sound pressure levels than in studies of annoyance from traffic noise. There is no scientific evidence that noise at levels created by wind turbines could cause health problems other than annoyance. No studies on noise from wind turbines in wilderness areas have been found, but the reaction to other noise sources such as aircraft have been studied. In recreational areas, the expectation of quietness is high among visitors, but wind turbines are, in contrary to aircraft, stationary and could be avoided by recreationists. The visual impact of wind turbines might though be the dominant source of annoyance. Regulations on noise from wind turbines are based on different principles. Some states, e.g. Denmark, have a special legislation concerning wind turbines, while others, like Sweden, have used recommendations originally developed for a different noise source. The noise level could either be absolute, as in Germany, or related to the background noise level as in France. This background noise level could be standardised, measured or related to wind speed

Vertical axis wind turbine

International Nuclear Information System (INIS)

Obretenov, V.; Tsalov, T.; Chakarov, T.

2012-01-01

In recent years, the interest in wind turbines with vertical axis noticeably increased. They have some important advantages: low cost, relatively simple structure, reliable packaging system of wind aggregate long period during which require no maintenance, low noise, independence of wind direction, etc.. The relatively low efficiency, however, makes them applicable mainly for small facilities. The work presents a methodology and software for approximately aerodynamic design of wind turbines of this type, and also analyzed the possibility of improving the efficiency of their workflow

Sound wave contours around wind turbine arrays

International Nuclear Information System (INIS)

Van Beek, A.; Van Blokland, G.J.

1993-02-01

Noise pollution is an important factor in selecting suitable sites for wind turbines in order to realize 1000 MW of wind power as planned by the Dutch government for the year 2000. Therefore an accurate assessment of wind turbine noise is important. The amount of noise pollution from a wind turbine depends on the wind conditions. An existing standard method to assess wind turbine noise is supplemented and adjusted. In the first part of the investigation the method was developed and applied for a solitary sound source. In the second part attention is paid to the use of the method for wind turbine arrays. It appears that the adjusted method results in a shift of the contours of the permitted noise level. In general the contours are 15-25% closer to the wind farm, which means that the minimal permitted distance between houses and wind turbine arrays can be reduced. 14 figs., 1 tab., 4 appendices, 7 refs

Wake characteristics of wind turbines in utility-scale wind farms

Science.gov (United States)

Yang, Xiaolei; Foti, Daniel; Sotiropoulos, Fotis

2017-11-01

The dynamics of turbine wakes is affected by turbine operating conditions, ambient atmospheric turbulent flows, and wakes from upwind turbines. Investigations of the wake from a single turbine have been extensively carried out in the literature. Studies on the wake dynamics in utility-scale wind farms are relatively limited. In this work, we employ large-eddy simulation with an actuator surface or actuator line model for turbine blades to investigate the wake dynamics in utility-scale wind farms. Simulations of three wind farms, i.e., the Horns Rev wind farm in Denmark, Pleasant Valley wind farm in Minnesota, and the Vantage wind farm in Washington are carried out. The computed power shows a good agreement with measurements. Analysis of the wake dynamics in the three wind farms is underway and will be presented in the conference. This work was support by Xcel Energy (RD4-13). The computational resources were provided by National Renewable Energy Laboratory.

Introduction to wind turbine aerodynamics

CERN Document Server

Schaffarczyk, Alois Peter

2014-01-01

Wind-Turbine Aerodynamics is a self-contained textbook which shows how to come from the basics of fluid mechanics to modern wind turbine blade design. It presents a fundamentals of fluid dynamics and inflow conditions, and gives a extensive introduction into theories describing the aerodynamics of wind turbines. After introducing experiments the book applies the knowledge to explore the impact on blade design.The book is an introduction for professionals and students of very varying levels.

Vertical-axis wind turbine development in Canada

Science.gov (United States)

Templin, R. J.; Rangi, R. S.

1983-12-01

Recent Canadian progress in the development of the curved-blade Darrieus vertical-axis wind turbine (VAWT) is described. Cooperation between government, industry and power utilities in the conduct of field trials, over several years, has demonstrated improved performance and reliability of grid-coupled turbines of this type. The rated power of the VAWTs currently under test ranges from 30 kW, in a wind/diesel powerplant, to 230 kW, in an installation on an island in the Gulf of St. Lawrence. Progress has also been made in understanding the basic aerodynamic behavior of the VAWT and theoretical methods for performance and load prediction have correspondingly improved. A brief description is given of 'Project EOLE', a cooperative project between the federal government and the utility Hydro-Quebec to develop and test, during the next two to three years, a 4 MW VAWT prototype, which will be coupled to the power grid at a location on the south shore of the St. Lawrence River.

Cooperative wind turbine control for maximizing wind farm power using sequential convex programming

International Nuclear Information System (INIS)

Park, Jinkyoo; Law, Kincho H.

2015-01-01

Highlights: • The continuous wake model describes well the wake profile behind a wind turbine. • The wind farm power function describes well the power production of a wind farm. • Cooperative control increases the wind farm power efficiency by 7.3% in average. • SCP can be employed to efficiently optimize the control actions of wind turbines. - Abstract: This paper describes the use of a cooperative wind farm control approach to improve the power production of a wind farm. The power production by a downstream wind turbine can decrease significantly due to reduced wind speed caused by the upstream wind turbines, thereby lowering the overall wind farm power production efficiency. In spite of the interactions among the wind turbines, the conventional (greedy) wind turbine control strategy tries to maximize the power of each individual wind turbine by controlling its yaw angle, its blade pitch angle and its generator torque. To maximize the overall wind farm power production while taking the wake interference into account, this study employs a cooperative control strategy. We first derive the wind farm power as a differentiable function of the control actions for the wind turbines in a wind farm. The wind farm power function is then maximized using sequential convex programming (SCP) to determine the optimum coordinated control actions for the wind turbines. Using an example wind farm site and available wind data, we show how the cooperative control strategy improves the power production of the wind farm

Development of a Fault Monitoring Technique for Wind Turbines Using a Hidden Markov Model.

Science.gov (United States)

Shin, Sung-Hwan; Kim, SangRyul; Seo, Yun-Ho

2018-06-02

Regular inspection for the maintenance of the wind turbines is difficult because of their remote locations. For this reason, condition monitoring systems (CMSs) are typically installed to monitor their health condition. The purpose of this study is to propose a fault detection algorithm for the mechanical parts of the wind turbine. To this end, long-term vibration data were collected over two years by a CMS installed on a 3 MW wind turbine. The vibration distribution at a specific rotating speed of main shaft is approximated by the Weibull distribution and its cumulative distribution function is utilized for determining the threshold levels that indicate impending failure of mechanical parts. A Hidden Markov model (HMM) is employed to propose the statistical fault detection algorithm in the time domain and the method whereby the input sequence for HMM is extracted is also introduced by considering the threshold levels and the correlation between the signals. Finally, it was demonstrated that the proposed HMM algorithm achieved a greater than 95% detection success rate by using the long-term signals.

Meteorological Controls on Wind Turbine Wakes

DEFF Research Database (Denmark)

Barthelmie, Rebecca J.; Hansen, Kurt Schaldemose; Pryor, S.C.

2013-01-01

, modeling, and predicting this complex and interdependent system is therefore critical to understanding and modeling wind farm power losses due to wakes, and to optimizing wind farm layout. This paper quantifies the impact of these variables on the power loss due to wakes using data from the large offshore......The primary control on the magnitude of the power losses induced by wind turbine wakes in large wind farms is the hub-height wind speed via its link to the turbine thrust coefficient. Hence, at low to moderate wind speeds (between cut-in and rated turbine wind speeds) when the thrust coefficient...

Damping Wind and Wave Loads on a Floating Wind Turbine

DEFF Research Database (Denmark)

Christiansen, Søren; Bak, Thomas; Knudsen, Torben

2013-01-01

Offshore wind energy capitalizes on the higher and less turbulent wind speeds at sea. To enable deployment of wind turbines in deep-water locations, structures are being explored, where wind turbines are placed on a floating platform. This combined structure presents a new control problem, due......, and we show the influence that both wind speed, wave frequencies and misalignment between wind and waves have on the system dynamics. A new control model is derived that extends standard turbine models to include the hydrodynamics, additional platform degrees of freedom, the platform mooring system...

Stochastic Evaluation of Maximum Wind Installation in a Radial Distribution Network

DEFF Research Database (Denmark)

Chen, Peiyuan; Bak-Jensen, Birgitte; Chen, Zhe

2011-01-01

This paper proposes an optimization algorithm to find the maximum wind installation in a radial distribution network. The algorithm imposes a limit on the amount of wind energy that can be curtailed annually. The algorithm implements the wind turbine reactive power control and wind energy...... curtailment using sensitivity factors. The optimization is integrated with Monte Carlo simulation to account for the stochastic behavior of load demand and wind power generation. The proposed algorithm is tested on a real 20 kV Danish distribution system in Støvring. It is demonstrated that the algorithm...... executes reactive compensation and energy curtailment sequentially in an effective and efficient manner....

Smart Wind Turbine: Analysis and Autonomous Flap

OpenAIRE

Bernhammer, L.O.

2015-01-01

Wind turbines convert kinetic energy of the wind into electrical energy. Unfortunately, this process is everything but constant, as the wind source shows large fluctuations with high and low frequencies. This turbulence, together with the wind shear and yawed inflow, excites the turbine structure, thereby driving the loads and the design of turbines in general and blades in particular. In response to this, several control mechanisms have been applied to wind turbines since the generation of s...

Materials for Wind Turbine Blades: An Overview

DEFF Research Database (Denmark)

Mishnaevsky, Leon; Branner, Kim; Petersen, Helga Nørgaard

2017-01-01

A short overview of composite materials for wind turbine applications is presented here. Requirements toward the wind turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind turbine blades (glass fibers/epoxy matrix composites), natural...... composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind turbine composites, as well their testing and modelling approaches are reviewed....

Materials for Wind Turbine Blades: An Overview.

Science.gov (United States)

Mishnaevsky, Leon; Branner, Kim; Petersen, Helga Nørgaard; Beauson, Justine; McGugan, Malcolm; Sørensen, Bent F

2017-11-09

A short overview of composite materials for wind turbine applications is presented here. Requirements toward the wind turbine materials, loads, as well as available materials are reviewed. Apart from the traditional composites for wind turbine blades (glass fibers/epoxy matrix composites), natural composites, hybrid and nanoengineered composites are discussed. Manufacturing technologies for wind turbine composites, as well their testing and modelling approaches are reviewed.

Comparison of Standard Wind Turbine Models with Vendor Models for Power System Stability Analysis: Preprint

Energy Technology Data Exchange (ETDEWEB)

Honrubia-Escribano, A.; Gomez Lazaro, E.; Jimenez-Buendia, F.; Muljadi, Eduard

2016-11-01

The International Electrotechnical Commission Standard 61400-27-1 was published in February 2015. This standard deals with the development of generic terms and parameters to specify the electrical characteristics of wind turbines. Generic models of very complex technological systems, such as wind turbines, are thus defined based on the four common configurations available in the market. Due to its recent publication, the comparison of the response of generic models with specific vendor models plays a key role in ensuring the widespread use of this standard. This paper compares the response of a specific Gamesa dynamic wind turbine model to the corresponding generic IEC Type III wind turbine model response when the wind turbine is subjected to a three-phase voltage dip. This Type III model represents the doubly-fed induction generator wind turbine, which is not only one of the most commonly sold and installed technologies in the current market but also a complex variable-speed operation implementation. In fact, active and reactive power transients are observed due to the voltage reduction. Special attention is given to the reactive power injection provided by the wind turbine models because it is a requirement of current grid codes. Further, the boundaries of the generic models associated with transient events that cannot be represented exactly are included in the paper.

Upscaling wind turbines: theoretical and practical aspects and their impact on the cost of energy

DEFF Research Database (Denmark)

Sieros, G.; Chaviaropoulos, P.; Sørensen, John Dalsgaard

2012-01-01

Wind turbines with a rated power of 5 to 6 MW are now being designed and installed, mostly for offshore operation. Within the EU supported UpWind research project, the barriers for a further increase of size, up to 20 MW, are considered. These wind turbines are expected to have a rotor diameter up......‐efficient way. Finally, a theoretical framework for optimal design of large wind turbines is developed. This is based on a life cycle cost approach, with the introduction of generic models for the costs, as functions of the design parameters and using basic upscaling laws adjusted for technology improvement...... to 250 m and a hub height of more than 150 m. Initially, the theoretical implications of upscaling to such sizes on the weight and loads of the wind turbines are examined, where it is shown that unfavourable increases in weight and load will have to be addressed. Following that, empirical models...

Wind Turbine Generator System Safety and Function Test Report for the Southwest Windpower H40 Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

van Dam, J.; Link, H.; Meadors, M.; Bianchi, J.

2002-06-01

The objective of this test was to evaluate the safety and function characteristics of the Whisper H40 wind turbine. The general requirements of wind turbine safety and function tests are defined in the IEC standard WT01. The testing was conducted in accordance with the National Wind Technology Center (NWTC) Quality Assurance System, including the NWTC Certification Team Certification Quality Manual and the NWTC Certification Team General Quality Manual for the Testing of Wind Turbines, as well as subordinate documents. This safety and function test was performed as part of the U.S. Department of Energy's Field Verification Program for small wind turbines.

The use of wind data with an operational wind turbine in a research and development environment

Science.gov (United States)

Neustadter, H. E.

1979-01-01

It is noted that in 1976, 17 candidate sites were identified for detailed evaluation as potential sites for installation of large, horizontal axis Wind Turbines (WT). Attention is given to the Mod-OA, a 200 kW WT located in Clayton, New Mexico. The discussion covers the meteorological data collected, some of the analyses based on these wind data as well as additional areas currently being investigated in relation to these data.

Buckling Analysis of Bucket Foundations for Wind Turbines in Deep Water

DEFF Research Database (Denmark)

Madsen, Søren; Andersen, Lars; Ibsen, Lars Bo

2011-01-01

Using large suction caissons for offshore wind turbines is an upcoming technology also referred to as bucket foundations. The bucket foundation does not require heavy installation equipment, but since it is constructed as a thin steel shell structure, instability, in form of buckling, becomes...

Computer investigations of the turbulent flow around a NACA2415 airfoil wind turbine

Science.gov (United States)

Driss, Zied; Chelbi, Tarek; Abid, Mohamed Salah

2015-12-01

In this work, computer investigations are carried out to study the flow field developing around a NACA2415 airfoil wind turbine. The Navier-Stokes equations in conjunction with the standard k-ɛ turbulence model are considered. These equations are solved numerically to determine the local characteristics of the flow. The models tested are implemented in the software "SolidWorks Flow Simulation" which uses a finite volume scheme. The numerical results are compared with experiments conducted on an open wind tunnel to validate the numerical results. This will help improving the aerodynamic efficiency in the design of packaged installations of the NACA2415 airfoil type wind turbine.

Reliability Assessment Of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2014-01-01

Reduction of cost of energy for wind turbines are very important in order to make wind energy competitive compared to other energy sources. Therefore the turbine components should be designed to have sufficient reliability but also not be too costly (and safe). This paper presents models...... for uncertainty modeling and reliability assessment of especially the structural components such as tower, blades, substructure and foundation. But since the function of a wind turbine is highly dependent on many electrical and mechanical components as well as a control system also reliability aspects...... of these components are discussed and it is described how there reliability influences the reliability of the structural components. Two illustrative examples are presented considering uncertainty modeling, reliability assessment and calibration of partial safety factors for structural wind turbine components exposed...

Environmental impacts of wind power. Case study of wind turbines in living environment; Vindkraftens Miljoepaaverkan. Fallstudie av vindkraftverk i boendemiljoe

Energy Technology Data Exchange (ETDEWEB)

Widing, Angelica; Britse, Gunilla; Wizelius, Tore [Gotland Univ., Visby (Sweden). Windpower information centre

2006-06-15

introduced, for example on Gotland (minimum 1000 meters as a general recommendation, but with an option to reduce it to 500 meters if circumstances allow this), creates limitations for landowners to use their land close to wind turbines. Another factor that was found was that a landowner who has a wind turbine installed close to the border to his neighbors land, limits the neighbors opportunity to erect a turbine on his land, since there must be a minimum distance between turbines. This problem can be solved by defining the area used by a turbine as it's wind catchment area (a circle with a radius of 2,5 rotor diameters), instead of only the few square meters where the foundation is located.

Gone with the wind? The impact of wind turbines on tourism demand

International Nuclear Information System (INIS)

Broekel, Tom; Alfken, Christoph

2015-01-01

While wind energy production is relatively free from environmental externalities such as air pollution, it is frequently considered to negatively impact landscapes' visual aesthetic values, thereby inducing negative effects on tourism demand. Existing evidence for Germany indeed points towards a negative relationship between tourism demand and wind turbine construction. However, the existing studies primarily rely on interview data and simple bivariate statistics. In contrast, we make use of secondary statistics on tourism and wind turbine locations at the level of German municipalities. Using spatial panel regression techniques, we confirm a negative relation between wind turbines around municipalities and tourism demand for municipalities not located near the coast. In the latter regions, the relation between wind turbines and tourism demand is more complex. - Highlights: • Comprehensive quantitative empirical study on wind turbines and tourism demand. • Consideration of wind turbines in vacation municipalities and in their geographic surroundings. • Novel data set on wind turbines and touristic demand in all German municipalities. • Application of spatial panel analysis in the context of tourism research. • Evidence for a negative relationship between wind turbines and tourism demand.

A Review of Numerical Modelling of Multi-Scale Wind Turbines and Their Environment

Directory of Open Access Journals (Sweden)

Katrina Calautit

2018-03-01

Full Text Available Global demand for energy continues to increase rapidly, due to economic and population growth, especially for increasing market economies. These lead to challenges and worries about energy security that can increase as more users need more energy resources. Also, higher consumption of fossil fuels leads to more greenhouse gas emissions, which contribute to global warming. Moreover, there are still more people without access to electricity. Several studies have reported that one of the rapidly developing source of power is wind energy and with declining costs due to technology and manufacturing advancements and concerns over energy security and environmental issues, the trend is predicted to continue. As a result, tools and methods to simulate and optimize wind energy technologies must also continue to advance. This paper reviews the most recently published works in Computational Fluid Dynamic (CFD simulations of micro to small wind turbines, building integrated with wind turbines, and wind turbines installed in wind farms. In addition, the existing limitations and complications included with the wind energy system modelling were examined and issues that needs further work are highlighted. This study investigated the current development of CFD modelling of wind energy systems. Studies on aerodynamic interaction among the atmospheric boundary layer or wind farm terrain and the turbine rotor and their wakes were investigated. Furthermore, CFD combined with other tools such as blade element momentum were examined.

Tornado type wind turbines

Science.gov (United States)

Hsu, Cheng-Ting

1984-01-01

A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

Design of low noise airfoil with high aerodynamic performance for use on small wind turbines

Institute of Scientific and Technical Information of China (English)

Taehyung; KIM; Seungmin; LEE; Hogeon; KIM; Soogab; LEE

2010-01-01

Wind power is one of the most reliable renewable energy sources and internationally installed capacity is increasing radically every year.Although wind power has been favored by the public in general,the problem with the impact of wind turbine noise on people living in the vicinity of the turbines has been increased.Low noise wind turbine design is becoming more and more important as noise is spreading more adverse effect of wind turbine to public.This paper demonstrates the design of 10 kW class wind turbines,each of three blades,a rotor diameter 6.4 m,a rated rotating speed 200 r/min and a rated wind speed 10 m/s.The optimized airfoil is dedicated for the 75% spanwise position because the dominant source of a wind turbine blade is trailing edge noise from the outer 25% of the blade.Numerical computations are performed for incompressible flow and for Mach number at 0.145 and for Reynolds numbers at 1.02×106 with a lift performance,which is resistant to surface contamination and turbulence intensity.The objectives in the design process are to reduce noise emission,while sustaining high aerodynamic efficiency.Dominant broadband noise sources are predicted by semi-empirical formulas composed of the groundwork by Brooks et al.and Lowson associated with typical wind turbine operation conditions.During the airfoil redesign process,the aerodynamic performance is analyzed to reduce the wind turbine power loss.The results obtained from the design process show that the design method is capable of designing airfoils with reduced noise using a commercial 10 kW class wind turbine blade airfoil as a basis.Therefore,the new optimized airfoil showing 2.9 dB reductions of total sound pressure level(SPL) and higher aerodynamic performance are achieved.

Aeroservoelasticity of Wind Turbines

DEFF Research Database (Denmark)

Kallesøe, Bjarne Skovmose

2007-01-01

This thesis deals with the fundamental aeroelastic interaction between structural motion, Pitch action and control for a wind turbine blade. As wind turbines become larger, the interaction between pitch action, blade motion, aerodynamic forces, and control become even more important to understand......, and furthermore linear and therefore suitable for control design. The development of the primary aeroelastic blade model is divided into four steps: 1) Nonlinear partial differential equations (PDEs) of structural blade motion are derived together with equations of pitch action and rotor speed; the individual...... to a 2D blade section model, and it can be used instead of this in many applications, giving a transparent connection to a real wind turbine blade. In this work the aeroelastic blade model is used to analyze interaction between pitch action, blade motion and wind speed variations. Furthermore the model...

Siemens Wind Power 3.6 MW wind turbines for large offshore wind farms

Energy Technology Data Exchange (ETDEWEB)

Akhmatov, Vladislav; Nygaard Nielsen, Joergen; Thisted, Jan; Groendahl, Erik; Egedal, Per; Noertoft Frydensbjerg, Michael; Jensen, Kim Hoej [Siemens Wind Power A/S, Brande (Denmark)

2008-07-01

Siemens Wind power A/S is the key player on the offshore wind power market. The Siemens Wind Power 3.6 MW variable-speed wind turbine is among the word's largest, most advanced and competitive wind turbines with a solid portfolio of large offshore wind farms. Transmission system operators and developers require dynamic wind turbine models for evaluation of fault-ride-through capability and investigations of power system stability. The even larger size of the on- and offshore wind farms has entailed that the grid impact of the voltage and frequency control capability of the wind farm can be appropriated modelled and evaluated. Siemens Wind Power has developed a dynamic model of the 3.6 MW variable-speed wind turbine with the fault-ride-through sequences and models of the voltage and frequency controllers to be applied for large offshore wind farms. The dynamic models have been implemented in the commercially available simulation tools such as DIgSILENT PowerFactory and Siemens PTI PSS/E and successfully validated from measurements. (orig.)

Wind turbine with lightning protection system

DEFF Research Database (Denmark)

2016-01-01

The present invention relates to a wind turbine comprising a lightning protection system comprising a waveguide interconnecting a communication device and a signal-carrying structure. In other aspects, the present invention relates to the use of a waveguide in a lightning protection system...... of a wind turbine, a power splitter and its use in a lightning protection system of a wind turbine....

Optimal Structural Reliability of Offshore Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Tarp-Johansen, N.J.

2005-01-01

The main failure modes of modern large wind turbines are fatigue failure of wings, hub, shaft and main tower, local buckling of main tower, and failure of the foundation. This paper considers reliability-based optimal design of wind turbines. Compared to onshore wind turbines and building...... structures, humans spent little time in the vicinity of offshore wind turbines and the probability of human injury during storm conditions is small. Further environmental pollution will also in general be small in case of failure. One could therefore argue that the reliability level of offshore wind turbines...... can be lower than for onshore wind turbines and other civil engineering structures and can be assessed by reliability-based cost-optimization. Specifically this paper considers the main tower and foundation. Both fatigue and ultimate strength failure modes are included. Different formulations...

Design of Wind Turbine Vibration Monitoring System

Directory of Open Access Journals (Sweden)

Shoubin Wang

2013-04-01

Full Text Available In order to ensure safety of wind turbine operation and to reduce the occurrence of faults as well as to improve the reliability of wind turbine operation, a vibration monitoring for wind turbine is developed. In this paper, it analyses the enlargement of all the parts of the structure and the working mechanism, the research method of wind turbine operation vibration is introduced, with the focus being the use of the sensor principle. Finally the hardware design and software of this system is introduced and the main function of this system is described, which realizes condition monitoring of the work state of wind turbines.

Robust, Gain-Scheduled Control of Wind Turbines

DEFF Research Database (Denmark)

Østergaard, Kasper Zinck

Wind turbines are today large and efficient machines, which are combined into wind farms operating on par with conventional power plants. When looking back, this is significantly different from the status only a few years ago, when wind turbines were sold mainly to private people. This change...... in turbine owners has resulted in a new focus on operational reliability instead of turbine size. This research deals with investigating model-based gain-scheduling control of wind turbines by use of linear parameter varying (LPV) methods. The numerical challenges grow quickly with the model size...

Progress in wind tunnel experimental techniques for wind turbine?

Institute of Scientific and Technical Information of China (English)

Jingping XIAO; Li CHEN; Qiang WANG; Qiao WANG

2016-01-01

Based on the unsteady aerodynamics experiment (UAE) phase VI and the model experiment in controlled conditions (MEXICO) projects and the related research carried out in China Aerodynamic Research and Development Center (CARDC), the recent progress in the wind tunnel experimental techniques for the wind turbine is sum-marized. Measurement techniques commonly used for di?erent types of wind tunnel ex-periments for wind turbine are reviewed. Important research achievements are discussed, such as the wind tunnel disturbance, the equivalence of the airfoil in?ow condition, the three-dimensional (3D) e?ect, the dynamic in?ow in?uence, the ?ow ?eld structure, and the vortex induction. The corresponding research at CARDC and some ideas on the large wind turbine are also introduced.

Do Wind Turbines Affect Weather Conditions?: A Case Study in Indiana

Directory of Open Access Journals (Sweden)

Meghan F. Henschen

2011-01-01

Full Text Available Wind turbines are becoming increasingly widespread in the United States as the world looks for cleaner sources of energy. Scientists, policymakers, and citizens have strong opinions regarding the positive and negative effects of wind energy projects, and there is a great deal of misinformation about wind energy circulating on the Web and other media sources. The purpose of this study is to gain a better understanding of how the rotation of hundreds of turbines can influence local weather conditions within a wind farm and in the surrounding areas. This experiment measures temperature, atmospheric pressure, wind speed, wind direction, relative humidity, and evaporation with five weather instruments at Meadow Lake Wind Farm located in White, Jasper, and Benton Counties, Indiana, from November 4 through November 18, 2010. The data show that as wind passes throughout the wind farm, the air warms during the overnight and early morning hours and cools during daytime hours. Observed lower humidity rates and higher evaporation rates downwind also demonstrate that the air dries out as it travels through the wind farm. Further research over multiple seasons is necessary to examine the effects of warmer nighttime temperatures and drier conditions progressively downwind of the installation. Nevertheless, wind turbines did not negatively affect local weather patterns in our small-scale research and may actually prevent frost, which could have important positive implications for farmers by potentially prolonging the growing season.

Design and fabrication of a low-cost Darrieus vertical-axis wind-turbine system, phase 2. Volume 3: Design, fabrication, and site drawing

Science.gov (United States)

1983-03-01

The design, fabrication, and site drawings associated with fabrication, installation, and check out of 100 kW 17 meter Vertical Axis Wind Turbines (VAWTs) were reported. The turbines are Darrieus type VAWTs with rotors 17 meters in diameter and 25.15 meters in height. They can produce 100 kW of electric power at a cost of energy as low as 3 cents per kWh, in an 18 mph wind regime using 12% annualized costs. Four turbines are produced, three are installed and operable.

Sandia SWiFT Wind Turbine Manual.

Energy Technology Data Exchange (ETDEWEB)

White, Jonathan; LeBlanc, Bruce Philip; Berg, Jonathan Charles; Bryant, Joshua; Johnson, Wesley D.; Paquette, Joshua

2016-01-01

The Scaled Wind Farm Technology (SWiFT) facility, operated by Sandia National Laboratories for the U.S. Department of Energy's Wind and Water Power Program, is a wind energy research site with multiple wind turbines scaled for the experimental study of wake dynamics, advanced rotor development, turbine control, and advanced sensing for production-scale wind farms. The SWiFT site currently includes three variable-speed, pitch-regulated, three-bladed wind turbines. The six volumes of this manual provide a detailed description of the SWiFT wind turbines, including their operation and user interfaces, electrical and mechanical systems, assembly and commissioning procedures, and safety systems. Further dissemination only as authorized to U.S. Government agencies and their contractors; other requests shall be approved by the originating facility or higher DOE programmatic authority. 111 UNCLASSIFIED UNLIMITED RELEASE Sandia SWiFT Wind Turbine Manual (SAND2016-0746 ) approved by: Department Manager SWiFT Site Lead Dave Minster (6121) Date Jonathan White (6121) Date SWiFT Site Supervisor Dave Mitchell (6121) Date Note: Document revision logs are found after the title page of each volume of this manual. iv

Can road traffic mask sound from wind turbines? Response to wind turbine sound at different levels of road traffic sound

International Nuclear Information System (INIS)

Pedersen, Eja; Berg, Frits van den; Bakker, Roel; Bouma, Jelte

2010-01-01

Wind turbines are favoured in the switch-over to renewable energy. Suitable sites for further developments could be difficult to find as the sound emitted from the rotor blades calls for a sufficient distance to residents to avoid negative effects. The aim of this study was to explore if road traffic sound could mask wind turbine sound or, in contrast, increases annoyance due to wind turbine noise. Annoyance of road traffic and wind turbine noise was measured in the WINDFARMperception survey in the Netherlands in 2007 (n=725) and related to calculated levels of sound. The presence of road traffic sound did not in general decrease annoyance with wind turbine noise, except when levels of wind turbine sound were moderate (35-40 dB(A) Lden) and road traffic sound level exceeded that level with at least 20 dB(A). Annoyance with both noises was intercorrelated but this correlation was probably due to the influence of individual factors. Furthermore, visibility and attitude towards wind turbines were significantly related to noise annoyance of modern wind turbines. The results can be used for the selection of suitable sites, possibly favouring already noise exposed areas if wind turbine sound levels are sufficiently low.

Concurrent Aeroservoelastic Design and Optimization of Wind Turbines

DEFF Research Database (Denmark)

Tibaldi, Carlo

This work develops and investigates methods to integrate controllers in the wind turbine design process and to perform wind turbine optimization. These techniques can exploit the synergy between wind turbine components and generate new design solutions. Two frameworks to perform wind turbine...... optimization design are presented. These tools handle workflows to model a wind turbine and to evaluate loads and performances under specific conditions. Three approaches to evaluate loads are proposed and integrated in the optimization codes. The first method is based on time domain simulations, the second...... simulations, allows the selection of any controller parameter. The methods to evaluate loads and the pole-placement technique are then employed to carry out wind turbine optimization design from an aeroservoelastic prospective. Several analysis of the NREL 5 MW Reference Wind Turbine and the DTU 10 MW...

Flow separation on wind turbines blades

Science.gov (United States)

Corten, G. P.

2001-01-01

In the year 2000, 15GW of wind power was installed throughout the world, producing 100PJ of energy annually. This contributes to the total electricity demand by only 0.2%. Both the installed power and the generated energy are increasing by 30% per year world-wide. If the airflow over wind turbine blades could be controlled fully, the generation efficiency and thus the energy production would increase by 9%. Power Control To avoid damage to wind turbines, they are cut out above 10 Beaufort (25 m/s) on the wind speed scale. A turbine could be designed in such a way that it converts as much power as possible in all wind speeds, but then it would have to be to heavy. The high costs of such a design would not be compensated by the extra production in high winds, since such winds are rare. Therefore turbines usually reach maximum power at a much lower wind speed: the rated wind speed, which occurs at about 6 Beaufort (12.5 m/s). Above this rated speed, the power intake is kept constant by a control mechanism. Two different mechanisms are commonly used. Active pitch control, where the blades pitch to vane if the turbine maximum is exceeded or, passive stall control, where the power control is an implicit property of the rotor. Stall Control The flow over airfoils is called "attached" when it flows over the surface from the leading edge to the trailing edge. However, when the angle of attack of the flow exceeds a certain critical angle, the flow does not reach the trailing edge, but leaves the surface at the separation line. Beyond this line the flow direction is reversed, i.e. it flows from the trailing edge backward to the separation line. A blade section extracts much less energy from the flow when it separates. This property is used for stall control. Stall controlled rotors always operate at a constant rotation speed. The angle of attack of the flow incident to the blades is determined by the blade speed and the wind speed. Since the latter is variable, it determines

Canadian Estimate of Bird Mortality Due to Collisions and Direct Habitat Loss Associated with Wind Turbine Developments

Directory of Open Access Journals (Sweden)

J. Ryan. Zimmerling

2013-12-01

Full Text Available We estimated impacts on birds from the development and operation of wind turbines in Canada considering both mortality due to collisions and loss of nesting habitat. We estimated collision mortality using data from carcass searches for 43 wind farms, incorporating correction factors for scavenger removal, searcher efficiency, and carcasses that fell beyond the area searched. On average, 8.2 ± 1.4 birds (95% C.I. were killed per turbine per year at these sites, although the numbers at individual wind farms varied from 0 - 26.9 birds per turbine per year. Based on 2955 installed turbines (the number installed in Canada by December 2011, an estimated 23,300 birds (95% C.I. 20,000 - 28,300 would be killed from collisions with turbines each year. We estimated direct habitat loss based on data from 32 wind farms in Canada. On average, total habitat loss per turbine was 1.23 ha, which corresponds to an estimated total habitat loss due to wind farms nationwide of 3635 ha. Based on published estimates of nest density, this could represent habitat for ~5700 nests of all species. Assuming nearby habitats are saturated, and 2 adults displaced per nest site, effects of direct habitat loss are less than that of direct mortality. Installed wind capacity is growing rapidly, and is predicted to increase more than 10-fold over the next 10-15 years, which could lead to direct mortality of approximately 233,000 birds / year, and displacement of 57,000 pairs. Despite concerns about the impacts of biased correction factors on the accuracy of mortality estimates, these values are likely much lower than those from collisions with some other anthropogenic sources such as windows, vehicles, or towers, or habitat loss due to many other forms of development. Species composition data suggest that < 0.2% of the population of any species is currently affected by mortality or displacement from wind turbine development. Therefore, population level impacts are unlikely

Vertical axis wind turbines

Science.gov (United States)

Krivcov, Vladimir [Miass, RU; Krivospitski, Vladimir [Miass, RU; Maksimov, Vasili [Miass, RU; Halstead, Richard [Rohnert Park, CA; Grahov, Jurij [Miass, RU

2011-03-08

A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

'Wind turbine syndrome': fact or fiction?

Science.gov (United States)

Farboud, A; Crunkhorn, R; Trinidade, A

2013-03-01

Symptoms, including tinnitus, ear pain and vertigo, have been reported following exposure to wind turbine noise. This review addresses the effects of infrasound and low frequency noise and questions the existence of 'wind turbine syndrome'. This review is based on a search for articles published within the last 10 years, conducted using the PubMed database and Google Scholar search engine, which included in their title or abstract the terms 'wind turbine', 'infrasound' or 'low frequency noise'. There is evidence that infrasound has a physiological effect on the ear. Until this effect is fully understood, it is impossible to conclude that wind turbine noise does not cause any of the symptoms described. However, many believe that these symptoms are related largely to the stress caused by unwanted noise exposure. There is some evidence of symptoms in patients exposed to wind turbine noise. The effects of infrasound require further investigation.

Status of large scale wind turbine technology development abroad?

Institute of Scientific and Technical Information of China (English)

Ye LI; Lei DUAN

2016-01-01

To facilitate the large scale (multi-megawatt) wind turbine development in China, the foreign e?orts and achievements in the area are reviewed and summarized. Not only the popular horizontal axis wind turbines on-land but also the o?shore wind turbines, vertical axis wind turbines, airborne wind turbines, and shroud wind turbines are discussed. The purpose of this review is to provide a comprehensive comment and assessment about the basic work principle, economic aspects, and environmental impacts of turbines.