Wind Energy DIY Guide

Energy2green Wind And Solar Power System

The Energy 2 Green Manual Has Everything You Need To Build Your Very Own Functional Windmill Or Solar Panel, Including: Detailed Schematics and Diagrams Showing You Precisely How To Build Your Solar Panels (generates up to 200-watts each) or Windmill (generates up to 1000-Watts!) Including the Precise Measurements You Need For Optimum Performance! Step-by-Step Instructions So Easy To Follow that Even High School Students Can Build Fully Functional Solar Panels and Windmills! Where To Find The Materials You Need For Your Solar Panels or Windmill! Installation Instructions To Hook the Solar Panel or Windmill Up To Your Home! Detailed Maintenance Instructions and Schedule for Your Windmill or Solar Panel! More here...

Energy2green Wind And Solar Power System Overview

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Wind Turbine Industries Corporation

Wind Turbine Industries, Corp. 16801 Industrial Circle S.E. Prior Lake, MN 55372 (952)447-6064 Fax (952)447-6050 E-mail wtic windturbine.net Web www.windturbine.net President Archie J. Pavek Manager Steven T. Turek The exclusive manufacturer of the Jacobs wind energy systems since 1986. The wind plants range in size from 10kW to 20kW, with rotor sizes ranging from 23 ft. (7m) to 29 ft. (8.8 m). These systems can provide power for a broad range of applications, which include Grid Intertie (utility bill reduction) or off-grid remote battery charging. The Jacobs wind energy systems have over 70 years of history providing clean, quality, reliable and efficient power in the USA and around the world. North American Distributor for African Wind Power Choose a Wind Generator Issue 90, page 50

The Future of Wind Power

As we said at the beginning of this section, wind power has a great potential future for large grid-powered wind farm applications. Even though you can find many examples of small and medium sized wind machines that turn three-phase alternators, the real future for wind power is in large installations. The economics of wind power versus fossil fuel are growing narrower thus making wind power a likely candidate for future power plants. Only politics and resistance to change still keep this technology from becoming commonplace. However, this is today's situation. Tomorrow is a different story, entirely. Wind power will require both power electronics and engineers skilled in the art of wind-driven turbines to continue on its successful path to acceptance and reality. Hopefully, what you've learned here and in Experiment 5 will help to influence your interest in this amazing technology.

The Rutland Windcharger

The Rutland Windcharger's fine profile aerodynamically efficient blades and unique low friction generator ensure maximum performance from its 910mm (36) diameter turbine. An Inventory of all Rutland Windchargers is held in our Buffalo Warehouse One of the world's leading wind powered battery chargers proven by over 15,000 customers worldwide One of the world's leading wind powered battery chargers proven by over 15,000 customers worldwide

Wind Speed Distributions

Rayleigh Distribution Wind

If data are not available, then the wind speeds can be predicted from one or two parameters. A number of different distributions have been tried, but only two are in general use, Rayleigh and Weibull distributions. These distributions give poor estimates of power for low mean wind speed situations. At higher wind speeds, both give adequate estimates for many locations however, for those regions with steady winds, such as the trade winds, the Weibull distribution is better. The Rayleigh distribution is simpler because it depends only on the mean wind speed. The Rayleigh distribution is where F(v) frequency of occurrence associated with each wind speed, v, which is at the center of Av Av width of class or bin and va average wind speed (same as mean wind speed) The wind speed histogram for 1 year can be calculated from 8,760 * F(v). The Rayleigh frequency is calculated for two different values, v 3 m s and v 9 m s, with va 8 m s and Av 2 m s Note As a check, the sum of the frequencies...

Concepts and wind turbine configurations

The generator and power electronic configurations most commonly applied in wind turbines are displayed in Figure 2. Figure 2. Standard wind turbine configurations using the asynchronous generator (AG) and the synchronous generator (SG). Depending on the particular configuration, the term Power Converter covers different types of power electronic components such as a soft starter (part a), an external variable rotor resistance (part c), a rectifier (part e - stator connected or part f, g, h - rotor connected) and a frequency converter (part b, d, e, g and h). The configurations depicted in Figure 2 present an outline of typical electrical topologies used in wind turbines. As listed in Table 1, these seven configurations cover a wide range of the applied power control concepts for wind turbines. a) This is the conventional concept applied by many Danish wind turbine manufacturers during the 1980's and 1990's, i.e. an upwind, stall regulated, three bladed wind turbine concept using an...

Wind Speed Histograms

A wind speed histogram shows the number of hours (or whatever time period is used) the wind blew at each wind speed class (Table 3.5). Wind speeds were sampled at 1 Hz and averaged for 1 h, and year wind speed histograms for 1996-1999 were averaged to obtain a representative annual value. An average density of 1.1 kg m3 was used to calculate the average wind power potential. The average wind speed was 8.2 m s, and the average wind power potential was 467 W m2 for a height of 50 m. The plots of the wind speed histogram and energy histogram (Figure 3.12) show the relationship between the two. There is little energy in low wind speeds because of the low wind speed, and little energy at high wind speeds because of the small amount of time of high wind speeds. Annual Average Wind Speed Histogram, Frequency and Calculation of Mean Wind Speed and Wind Power Potential at 50 m for White Deer, Texas, 1996-1999 Annual Average Wind Speed Histogram, Frequency and Calculation of Mean Wind Speed and...

Evaluation of global wind power

1 The goal of this study is to quantify the world's wind power potential for the first time from data. Wind speeds are calculated at 80 m, the hub height of modern, 77-m diameter, 1500 kW turbines. Since relatively few observations are available at 80 m, the Least Square extrapolation technique is utilized and revised here to obtain estimates of wind speeds at 80 m given observed wind speeds at 10 m (widely available) and a network of sounding stations. Tower data from the Kennedy Space Center (Florida) were used to validate the results. Globally, 13 of all reporting stations experience annual mean wind speeds > 6.9 m s at 80 m (i.e., wind power class 3 or greater) and can therefore be considered suitable for low-cost wind power generation. This estimate is believed to be conservative. Of all continents, North America has the largest number of stations in class > 3 (453), and Antarctica has the largest percent (60 ). Areas with great potential are found in northern Europe along...

Performance Of Voltage Control Unit Vcu At Cronalaght Wind Farm Ireland

Control design and dynamic performance analysis of a wind turbine induction generator unit. In POWERCON '98, International Conference on Power System Technology Vol. 2. 1198-1202 Asplund,G. (2000). HVDC transmission systems - new converter and cable technologies. In First international workshop on HVDC transmission networks for offshore wind farms. Stokholm, Sweden. Notes March Bindner,H.W. (1999a). Performance of Voltage Control Unit (VCU) in Cronalaght Wind Farm, Ireland. Ris0 National Laboratory, Denmark. Ris0-I-1484(EN), Bindner,H.W. (1999b). Power control for Wind Turbines in Weak Grids Project summary. Ris0 National Laboratory, Denmark. Ris0-R-1117(EN)., Blaabjerg,F.,& Mohan,N. (1999). Wind Power. In Encyclopaedia of Electrical and Electronics Engineering. Vol. 23. 613-618, Wiley. BTM Consults Aps. (2000). International Wind Energy Development -World Market Update 1999. Ringk0bing, Denmark BTM Consults Aps. ISBN 87-987788-0-3, Notes Forecast...

Amsc In Mw Superconducting Wind Turbine Development Plan With Us

A 10 MW-class superconducting wind turbine is to be economically evaluated under the terms of a Cooperative Research and Development Agreement (CRADA) between the US Department of Energy and technology company American Superconductor Corporation (AMSC). Together with the National Renewable Energy Laboratory (NREL) and the National Wind Technology Center (NWTC) AMSC Windtec, a wholly-owned subsidiary, will analyse the cost of a 10 MW-class machine featuring a direct drive superconductor generator. Windtec is separately developing full 10 MW-class wind turbine components and system designs and under the 12-month programme, will benchmark and evaluate the turbine's economic impact, both in terms of its initial cost and its overall cost of energy. Direct drive wind generator systems utilizing high The new move into wind technology follows the development of a superconducting marine propulsion system for the US Navy. Concurrent with the CRADA, AMSC and TECO-Westinghouse Motor Company...

Windmachine Home Made

JACOBS WIND ELECTRIC replacement parts, new blades, and blade-actuated governors. We make replacement parts and have new blades for most all wind generators, pre-REA to present models. Many used parts, too. Lots of used equipment available wind generators, towers, both synchronous and stand alone inverters, and Aermotor waterpumpers. Best prices on TRACE inverters. Information 1 specify interests. Lake Michigan Wind & Sun, 3971 E Bluebird RD., Forestville, WI 54213 Phone 414-837-2267. GREAT 5A. LAND for 5,000.(cash price). Area touted as Solar Wind Capital Colorado's 7,800' alt. valley. Plenty Best water (drill 80' for artesian flow), good access, privacy, loam soil. Fantastic View of 14,000' Mntns. Value climbing fast. Tot. taxes 65 yr. Was for son--No longer have. No gimmicks, No lies--honest bargain. 5 mi. NW from Here-to-Stay owner H nn, Windpowered Domehouse, P.O. Box 312, Blanca, CO 81123 QUALITY PLAYING CARDS. 2 Sample Decks 5.00 5 10.00 12 20.00 24 30.00 36 40.00. PRODUCTS...

The Whisper Wind Powered Generator

Being in the business of repairing wind generators, I've seen a lot of junk come through the door. We witnessed the rebirth of the wind industry in the late 1970s with about 80 wind generator companies setting up shop. Virtually all of these companies, which produced anywhere from a handful to a few hundred mostly Rube Goldberg units each, have gone bankrupt. About six have survived the shakedown. Needless to say, I'm quite skeptical when I hear of a new wind generator design. About a year ago, I talked to Elliot Bayly of World Power Technologies about the new design he was developing. Bayly has been in the business of manufacturing wind generators for 13 years. He is one of the survivors that I mentioned. I got the lowdown from him on his new machine and decided it was worth my while to pay him a visit. Last winter, I saw what I believe is the simplest wind generator design ever developed. My definition of simplicity is related to the number of moving parts a machine has. The greater...

The Lagerwey LW wind turbine

Wind Turbine Components

The Lagerwey LW-50 750 wind turbine is a 750 kW, variable speed wind turbine with an upwind rotor of 50.5-meter diameter. A picture of this turbine is shown in Fig. A.1. The LW-50 750 is located near Nieuwe-Tonge (Province of Zuid-Holland, The Netherlands). The rotor consists of 3 blades that can be actively and individually pitched over the full span. The pitch control is used for power control at full load, and to stop the turbine if the safe operating limits are exceeded. The turbine is equipped with a gearless (or direct-drive) synchronous ring-generator, which converts the mechanical power into electrical power at variable frequency. Subsequently, an insulated gate bipolar transistor (IGBT) based frequency converter is used to convert the electrical energy of varying frequency to the utility grid with a fixed 50-Hz frequency. The generator torque will follow an external set-point signal, which is calculated by the control computer. The support structure consists of a 46.165-meter...

Case Lagerwey LW wind turbine

Wind Turbine Schematic

The Lagerwey LW-50 750 wind turbine is located near Nieuwe-Tonge, Province of Zuid-Holland, The Netherlands. Fig. 4.13 shows a schematic of the measurement set-up of the full-scale modal test. The turbine was parked (i.e. non-rotating) during all testing. This implies that the bilateral coupling of the mechanical module to the electrical module, see Fig. 3.14 on page 69, can be omitted since the mechanical speed is equal to zero. Furthermore, the input from the aerodynamic module, Faero, is replaced by a static load applied to the tower top (hereby assuming that the structural response caused by wind excitation on the rotor blades, nacelle and tower is negligible). Figure 4.13 Schematic of the measurement set-up of the full-scale modal test performed on the Lagerwey LW-50 750 wind turbine. Sensor locations are marked with a I. The rotor was yawed 90 degrees about the y-axis during the experiments. The mechanical structure is excited by applying the aforementioned static load to the...

Wind speed probability distributions Weibull and Rayleigh

Weibull Shape Factor Increase

The analysis of Example 9.1 depended solely on field data and repetitive numerical calculation. It would be extremely useful if the important function the probability distribution of wind speed, could be given an algebraic form that accurately fitted the data. Two advantages follow (1) fewer data need be measured, and (2) analytic calculation of wind machine performance could be attempted. For sites without long periods of zero wind, i.e. the more promising sites for wind-power, usually with u > 5ms 1, usually a two-parameter exponential function can be closely fitted to measure wind speed data. One such function, often used in wind speed analysis, is the Weibull function shown in Figure 9.22 obtained from Figure 9.22 shows the form of Qu> u' and for different values of k around 2.0. Such curves often give very good fit to experimental data, with k between 1.8 and 2.3 and c near the mean wind speed for the site. See also Figure 9.18, which compares actual data for North Ronaldsay...

Specific Output kWhm for Wind Turbines Most but Not All Manufacturers in California

Windpower In the 1990s, the older wind turbines, primarily in the range of 50-100 kW (55 of the MW capacity installed), were being cannibalized for parts and uneconomic wind turbines were dismantled. The following trends are noted wind turbines became larger (now megawatts), capacity factors were better, and reliability increased. Also, the drop in production in 1997 was due to older, smaller units being taken out of production and then replaced with bigger turbines in 1998. As the poor-performing units were taken out of service and newer wind turbines installed, specific output (Figure 8.4) increased. The larger specific output shows the type of performance that can be expected with good wind turbines in an excellent wind regime. For both annual capacity factor and specific output, for the same turbines, there will be annual variations by year due to difference in the yearly wind regime and between locations, as wind is site specific.

Pole Pipe Wind Turbine Tower

Utility Pole With Two Guy Wires

Having purchased a Windseeker II wind electric turbine, we faced the daunting prospect of erecting a tower. The tower has to be at least 15 feet above surrounding obstacles. In our case this worked out to be 50 feet above the ground. Here are plans for a tower that is inexpensive, easy to build, and can be raised and lowered by a single person. This tower will support small to medium sized wind turbines. The tower consists of a 20 foot guyed utility pole with a three inch sleeve pipe U-bolted to the top. A smaller diameter pipe, with the wind turbine mounted on top, is winched up through this sleeve. The tower telescopes from full operating height to the partially-lowered maintenance position. Excavate 16 inches deep for a concrete pad to support the utility pole. Don't skip the pad unless you have very firm substrata vibration from the wind turbine will eventually break down even hard-packed soil. If the tower's base sinks, then the guy wires will become slack and ineffective. wind...

Wilson R.e. Lissaman P.b.s. And Walker S.n. 1976 Aerodynamic Performance Of Wind Turbines. Energy Research And

A catalog of low Reynolds number airfoil data for wind turbine applications. RFP-3387, Department of Aerospace Engineering, Texas A& M University. 3. R. E. Wilson, P. B. S. Lissaman, and S. N. Walker. 1976. Aerodynamic performance of wind turbines. ERDA NSF 04014-76-1, UC-60. Available from NTIS. 4. D. M. Eggleston and F. S. Stoddard. 1987. Wind turbine engineering design. New York Van Nostrand Reinhold. 5. D. Le Gourieres. 1982. Wind power plants, theory and design. Oxford, UK Pergamon Press. 6. L. L. Freris, ed. 1990. Wind energy conversion systems. Englewood Cliffs, NJ Prentice Hall. 7. D. A. Spera, ed. 1994. Wind turbine technology. New York ASME Press. 8. Wind energy conversion. C00-4131-Ti. Available from NTIS. Nine separate reports Methods for Design Analysis of Horizontal Axis Wind Turbines Aerodynamics of Horizontal Axis Wind Turbines Dynamics of Horizontal Axis Wind Turbines Drive System Dynamics Experimental Investigation of a Horizontal Axis Wind...

Wind energy penetration levels

Although the British and Danish system operators have both stated that the limits to wind energy penetration are economic rather than technical, this has gone largely unnoticed. There is still a feeling that high wind energy penetrations will cause severe technical problems but this is simply not the case. Extra costs are incurred but these can be quantified. A recent Danish study (Pedersen et al, 2006) has suggested that these extra costs reach a maximum value of around 15 MWh of wind. If markets can be found for the surplus wind (when wind output exceeds consumer demands), then that figure comes down. The overall message is very clear. High wind energy penetrations can be accommodated on electricity networks without any 'step changes' in additional costs being incurred. The results from the Danish analysis (Pedersen et al, 2006) have been set alongside an analysis for the UK system using the methods of Dale et al (2004). The results from the two studies show a good measure of...

The New Bergey Bwc Wind Turbine

With an output of 850 watts at a wind speed of 28 mph, the BWC 850 incorporates all the design features that have made Bergey wind turbines the standard for quality and performance throughout the world. Call or write for more information about the BWC 850. Or ask about our world class 1.5 kw and 10.0 kw wind turbines. BERGEY WINDPOWER CO., INC.

How To Make A Furling Wind Turbine Tail

Guy Tower Equalizer Plate

Randy Brooks and the owners were willing to allow the installation to be a demonstration project. Northwest Sustainable Energy for Economic Development (NW SEED) invited a group of individuals to monitor the installation. The group included a solar equipment distributor in Oregon interested in getting into the wind industry, a business development director for a general contractor from central Washington, and an SEI graduate and Bergey certified dealer from Spokane, among others. All fees the NW SEED participants paid were used to offset the cost of the installation. In return, June had an endless flow of coffee, snacks, and sandwiches for all. Bill Hoffer brought an inverter and Randy brought some batteries, charged from his Bergey XL.1 wind machine at home, to provide remote power for electric tools on site. This came in handy when a little on-site engineering was needed to help hold the tower off the ground. Randy used his Sawzall to turn the 4 by 4 framed turbine-shipping pallet...

Vertical Wind Turbine - 200kw Vawt

Sandia Test Bed Vawt

World energy production in 1995 was estimated at 5 million MWh year from over 22,000 wind turbines with an installed capacity of around 4,000 MW. The American Wind Energy Association set a very optimistic goal for the United States of 10,000 MW by the year 2000. This was not achieved, although there was a lot of activity in other states outside of California due to the new incentive of the production tax credit (PTC) for 1990-1995. The PTC was 0.015 kWh for 10 years, with an inflation factor for wind farms installed in later years. The PTC was extended a number of times however, late extension meant hardly any installations during that year. Sandia Labs managed the DOE program for VAWTs. A 34 m VAWT test bed, 500 kW, was tested at USDA-ARS, Bushland, Texas, from 1988 to 1998 (Figure 10.10). The DOE program, managed by the National Wind Technology Center, NREL, was changed to assistance and R& D for the U.S. industry to meet the foreign competition through the Advanced Wind Turbine...

World Leader In Offshore Foundation Design For Wind Turbines

Ramboll Wind has an unrivalled track record in the delivery of wind energy projects ranging from traditional onshore and offshore turbines to incorporating wind energy generation in skyscrapers and turbines floating in 200 metres of water. Ramboll Wind provides consultancy and engineering services within all areas of a wind project. Innovative thinking combined with years of offshore and wind experience makes Ramboll the world leader in offshore foundation concepts and design for wind turbines, and enables us to provide world class engineering for the wind energy industry. Ramboll Wind Energy is part ofthe Ramboll Group, a leading European engineering consultancy firm, which employs more than 8,000 dedicated specialists. Although progress has been substantial in China, there continue to be gaps in the emerging wind power system that need to be addressed. First, Beijing has not yet completed a policy for pricing wind power. The 'Trial Measures for Renewable Energy Power Generation...

Offshore Wind Farm Development

An offshore installation has advantages over and above the reduction in turbine costs from the resulting economies of scale. The marine environment is windier resulting in an increased energy yield, and the winds are more persistent and less turbulent making system-wide integration easier. Very large wind turbines that might cause an unacceptable visual intrusion onshore may well be acceptable if sited away from the shore. Additionally, the transportation of exceptionally large or heavy items is easier over water than over land where roads may need widening of reinforcement. Importantly, planning approval may be easier to obtain for offshore schemes due to their reduced visual and noise impact. Such advantages will become increasingly important as the acceptable onshore sites are progressively used up. At present, offshore wind energy is more expensive than on shore, primarily due to significantly higher foundation, installation and electrical connection costs. Complex and costly...

Wind farm and generator protection

Ring Main Wind Farm

Figure 10.20 shows a typical protection arrangement for a wind farm of fixed-speed wind turbines with generator voltages of 690 V and with a collection circuit voltage of 11 kV. The 11 kV circuit is fed from a 33 11 kV Delta Star wound transformer with the 11 kV neutral grounded either directly or through a resistor. The 11 0.69 kV transformers are also wound Delta Star and so the 690 V neutral points of each circuit may be directly grounded. The neutral point of the generators is not connected to ground. There are a number of zones of protection. At the base of the wind turbine tower a 690 V circuit breaker (usually a moulded case type as shown in Figure 10.1) will be fitted to protect the pendant cables and the generator. This is shown as Zone D. Figure 10.20 Protection of a Wind Farm with an 11 kV Connection Circuit (RMU - Ring Main Unit) fitted to the 690 V side of the turbine transformer to provide protection of the cables and also a point of isolation so that all the electrical...

Earthing Grounding of Wind Farms

Horizontal Electrode

Wind farms, however, have rather unusual requirements for earthing. They are often very extensive stretching over several kilometres, subject to frequent lightning strikes because of the height of modern wind turbines, and are often on high-resistivity ground being located on the tops of hills. Thus, normal earthing practice tends not to be easily applicable and special consideration is required. The IEEE Recommended Practice (1991), which is no longer current, recommended 'that the entire wind farm installation have a continuous metallic ground system connecting all equipment. This should include, but not be limited to, the substation, transfor mers, towers, wind-turbine generators and electronic equipment.' This practice is generally followed with bare conductor being laid in the power-collection cable trenches to provide both bonding of all parts of the wind farm as well as a long horizontal electrode to reduce the impedance of the earthing system. A wind farm earthing system is...

Variations In Wind Power Potential

Von Der Hoven Spectrum

Since the motion of the atmosphere varies on a scale from seconds to years, wind power and wind energy will also vary on the same time scale. The annual average wind power (6 m height) for Amarillo, Texas, was 220 watts m2 for the period 1962-1977 6 however, the variation from one year to the next can be quite large. A minimum of 2 years of data are needed to obtain an estimate for the annual wind power potential, and 5 years of data are needed to obtain a mean value within 6 of the long-term mean. Most people assume that if you have 2-3 years of data, then that will suffice, along with longer-term regional data for comparison, to determine the wind power potential. The annual wind power potential (Figure 3.14) for White Deer and Dalhart, Texas, shows the correlation between sites, which are 140 km apart in the same region. Data were sampled at 1 Hz and averaged over 1 h. Therefore, for a region where long-term base data are available for comparison, 1-2 years of data would suffice...

History from windmill to wind turbine

Persian Vertical Axis Windmill

The historic development of using wind as a source of power shows an evolution from simple drag-type vertical-axis windmills generating mechanical power for local use, via stand-alone wind turbines designed for battery charging and single grid-connected wind turbines producing AC power using aerodynamic lift, to wind farms supplying electricity to the utility grid for distribution to the consumers. In this subsection we shall briefly review this transition from windmills to wind turbines. The next subsection presents an outlook on the future of wind power. Finally, the required improvements in both wind turbine design and operation to achieve and maintain cost-effective wind turbines are discussed. The lower cost of wind power to water power and the fact that more sites were available for windmills than there were for water mills caused an increase in the use of windmills. In The Netherlands, this growth contributed to the country's golden age (from 1590 till about 1670). As late as...

Wind Turbine Blade Rpm And Length Of Blade500 Kw

For those who know calculus, find the value of u (speed of drag device) that produces the maximum CP for a drag device. Use Equation 6.10, where v0 is the wind speed at infinity. For those who do not know calculus, find the value of u that produces the maximum CP for a drag device by plotting the curve (Equation 6.12) for different values of u (between 0 and 1). 6. Explain the difference in performance of a wind turbine if it 7. What is the maximum theoretical efficiency for a wind turbine What general principles were used to calculate this number 10. A rotor reaches maximum CP at a tip speed ratio of 7. Calculate rotor rpm for four different wind turbines (diameters of 5, 10, 50, and 100 m) at wind speeds of 10, 20, and 30 m s. 11. A wind turbine that operates at constant rpm will reach maximum efficiency at only one wind speed. What wind speed should be chosen For problems 12-18, specifications for a wind turbine are induction generator (rpm 65), fixed-pitch, rated power 300 kW, hub...

Extractable Limits Of Wind Power

A comparison can be made on the basis of the kinetic energy of the winds per unit area of the earth's surface. Of the solar input, only 2 is converted into wind power, and 35 of that is dissipated within 1 km of the earth's surface. This is the wind power available for conversion to other forms of energy. The amount extracted would be limited by the criteria of not changing the climate however, the uncertainties are very large in determining such criterion. Man would be substituting wind turbines for naturally occurring frictional features such as trees, mountains, etc. Gustavson 1 assumed the extractable limit as 10 of the available wind power within 1 km of the surface. When these values are applied to the contiguous forty-eight states of the United States, the limit would be 2 x 1012 W (2 TW), or 62 quads year. A similar analysis can be made for the world. Therefore, wind energy represents a very large energy source. On a global scale, wind can be compared to other renewable...

Nonuniform wind velocity

The velocity field of the wind may be non-uniform in time as well as in spatial distribution. The influence of time variations in wind speed on power output of a propeller-type wind energy converter has been touched upon in the previous subsection, although a detailed investigation involving the actual time dependence of the angular velocity Q was not included. In general, the direction of the wind velocity is also time dependent, and the conversion device should be able to successively align its rotor axis with the long-range trends in wind direction, or suffer a power reduction that is not just the cosine to the angle between the rotor axis and the wind direction (yaw angle), but involves calculating the performance of each blade segment for an apparent wind speed W and angle of attack a different from the Assuming that both the wind direction and the wind speed are functions of time and of height h (measured from ground level or from the height z0, where the wind speed profile...

California Wind Farms

The California Energy Commission (CEC) instituted a program in 1984 for Wind Performance Reporting System regulations 5 . All California wind projects greater than 100 kW that sell electricity to a power purchaser have to report quarterly performance. The quarterly reports contain the following information turbine manufacturers, model numbers, rotor diameters and kilowatter ratings, number of cumulative and new turbines installed, the projected output per turbine, the output for each turbine model, and the output for the entire project. The annual report is a compilation of data from the four quarters and contains summary tables reflecting resource areas. The reports do not provide information on every wind energy project in California, as nonoperating wind projects and those turbines that do not produce electricity for sale, such as those installed by utilities, government organizations, and research facilities, do not file reports. Wind performance report summaries are available...

Innovative Wind Systems

Rotating Cylinder Electrode Photos

Innovative or unusual wind systems (Figure 5.17) have to be evaluated in the same way as other wind turbines. The important categories are system performance, structural requirements, and quantity and characteristics of materials. Innovative ideas include the tornado type, tethered units to reach the high winds of the jet stream, tall tower to use rising air, tall tower and humid air, torsion flutter, electrofluid, diffuser augmented, the Magnus effect, and others. Many of these have been reported in Popular Science 2-4 . Most all innovative concepts remain at the feasibility or lab experiment stage. Not all innovative systems are recent inventions for example, sail wings, wings on railroad cars, and the Magnus effect (Madaras concept was rotating cylinders on railroad cars) have been around for a long time. The West German government funded the construction of a 200 m tall tower in Spain 5 . A 240 m diameter greenhouse at the bottom provided the hot air to drive the air turbine,...

Subproblem Modeling of flexible wind turbines

First of all, given the fact that considerable effort has been put in the development of DAWIDUM, a warm recommendation is given to fully exploit the potential of this new wind turbine design code. This requires the joint effort of all DUWIND members to develop and implement new models as well as wind turbine specific analysis and (control) design tools. In addition, the code must be extended with a wave and hydrodynamic module required to compute the water wave forces acting on the support structure of wind turbines located offshore. The latter extension is essential, since the future of wind energy will be in large-scale offshore wind farms. It is recommended to develop an optimization procedure that calculates the optimal number of blade elements (independently of the number of superelements) for a given wind turbine configuration. At present, the superelement method used to model the flexible wind turbine part considers bending deformation only. It must be noted that both axial...

Wind Turbine Recipe Book November Metric Edition

4maximum power point tracking (MPPT), it's quite an exciting avenue of wind turbine development. 4maximum power point tracking (MPPT), it's quite an exciting avenue of wind turbine development. The basic direct battery-charging design without a converter has poor efficiency in stronger winds because of the high resistance in the stator (caused by the need to cut in at low rpm) and also the tendency to stall the blades (for the same reason). Bui it does have the advantage of simplicity and reliability. Reliability is the biggest problem with small wind turbines, outstripping any efficiency problems. The slowly turning rotor blades of the direct-connected turbine are also very quiet and suffer less wear and tear. You may wish to use a relay to disconnect the transformers when the wind turbine is turning slowly because the current they use in low windspeeds can impede startup.

Introduction general wind turbine model

A horizontal-axis wind turbine basically consists of five physical components, viz. rotor, transmission, generator, tower (including foundation) and control system. The rotor converts wind power into mechanical power, which is represented by the product of torque and angular velocity of the rotor shaft. This velocity is increased by the transmission in order to come to an angular velocity well-suited for the generator. The generator in its turn converts the mechanical power into electrical power. The transmission as well as the generator are housed in the nacelle. The tower plus foundation are needed to support the nacelle and besides that, they place the rotor into more windswept layers of air. Finally, the main goal of the control system is to enhance the closed-loop performance. integration of the design of a new wind turbine and the design of its control system. In order to enable this integrated design, we have developed a novel design tool called DAWIDUM. DAWIDUM is equipped...

Flow states of a wind turbine rotor

In the previous chapters, a wind turbine is assumed to be operating in its intended state in which kinetic energy is extracted from the wind. The rotor converts the extracted energy into mechanical energy thereby producing a downwind force while slowing down the free-stream wind velocity accordingly. This operating state requires that the axial induction factor lies between zero and unity. This operating state comprises two so-called rotor flow states, notably the windmill and the turbulent wake state. Besides these two flow states, a number of other flow states can be distincted. The axial induction factor a, or equivalently the thrust coefficient Cdax, can be used to characterise these different flow states. The following flow states may occur

Aerodynamics of Horizontal Axis Wind Turbines

To study the aerodynamics of wind turbines some knowledge of fluid dynamics in general is necessary and, in particular, aircraft aerodynamics. Excellent text books on aerodynamics are readily available, a bibliography is given at the end of this chapter, and any abbreviated account of the subject that could have been included in these pages would not have done it justice recourse to text books would have been necessary anyway. Some direction on which aerodynamics topics are necessary for the study of wind turbines would, however, be useful to the reader. A wind turbine is a device for extracting kinetic energy from the wind. By removing some of its kinetic energy the wind must slow down but only that mass of air which passes through the rotor disc is affected. Assuming that the affected mass of air remains separate from the air which does not pass through the rotor disc and does not slow down a boundary surface can be drawn containing the affected air mass and this boundary can be...

Wind turbines with horizontal rotor axis System components

Wind Turbine Blade Azimuth Angle

Most wind turbines generating electricity today are horizontal axis machines. It is predominantly medium-sized enterprises that have pushed wind market developments. Wind power plants have reached a high technical level and Figure 5.12 Section through the Stall-controlled TW600 Wind Generator (600 kW Change-pole Asynchronous Generator, 43 m Rotor Diameter, 50-70 m Hub Height) Figure 5.12 Section through the Stall-controlled TW600 Wind Generator (600 kW Change-pole Asynchronous Generator, 43 m Rotor Diameter, 50-70 m Hub Height) current systems reach powers up to several megawatts, whereas the wind generators of the 1980s were in the power range below 100 kW. A horizontal axis wind turbine generally consists of the following components (see Figure 5.12)

Wind Energy Technologies

While old-fashioned windmills are still seen in many rural areas for pumping water, modern wind turbines are divided into two major categories horizontal axis turbines and vertical axis turbines. Producing 204 megawatts, this is the third largest wind power plant in the world. The New Mexico Wind Energy Center has 136 turbines, 320 feet high. Producing 204 megawatts, this is the third largest wind power plant in the world. The New Mexico Wind Energy Center has 136 turbines, 320 feet high. A vertical axis wind turbine (VAWT) is likely to fall into one of two major categories Savonius and Darrieus, however neither turbine type is in wide use today. The basic theoretical advantages of a vertical axis machine are that the generator and gearbox can be placed on the ground and do not require a tower. Plus, you do not need a mechanism to turn the blades into the wind as you do with a horizontal axis machine. That said, the disadvantages of a Darrieus turbine far outweigh its advantages....

History of windmill and wind turbine control

Wind turbine control has a long history which was probably initiated by the regulation of the rotational speed of the Persian windmills in the tenth century A.D using a series of shutters. Another early example of a windmill regulation device is the mill-hopper which was used to regulate the flow of grain in a mill depending on the speed of rotation of the millstone by about 1588. The variability of the wind in both speed and direction was addressed and patented by the British blacksmith E. Lee in 1745 154 . The drawing annexed by Lee's patent is depicted in Fig. 7.1. To compensate for wind speed variations, he invented a mechanism that pitched the blades as the wind speed increased and vice versa. The general principle of working of this device was that the force of the wind pitched the blades when the force magnitude exceeded that of the counterweight. Figure 7.1 Drawing annexed by Lee's patent titled Self-regulating Wind Machine with A, the case of the Machine, B, the Sails, C, the...

Slowdown in Onshore Wind Power

As discussed in Chapter 2, one example of this can be seen in the present debate (2005 2010) on how to expand wind power in Denmark. The most cost-effective way is to increase the number of onshore wind turbines. From many years of experience, Danish society knows that this can be done if institutional frameworks are established in which neighbors own shares of the wind turbines and make a profit. Danish society also knows that if neighbors are not involved, they are likely to protest against this solution. However, based on the argument that wind power should adjust to the market, the institutional framework for neighbor-owned wind turbines has been abolished, and instead the government wants to expand offshore wind farms. Such wind farms are not economically competitive compared to onshore wind turbines, and they increase the need for subsidy. However, offshore wind farms correspond perfectly to the institutional framework of existing power companies. Figure 8.3 shows the...

Overview wind turbine design codes

In the wind energy community the following design codes are commonly used to model and simulate the wind turbine dynamic behavior, as well as to carry out design calculations ADAMS WT (Automatic Dynamic Analysis of Mechanical Systems - Wind Turbine) 57 . ADAMS WT is an add-on package for the general-purpose, multibody package ADAMS. ADAMS WT is developed by Mechanical Dynamics, Inc. (MDI) under contract to the National Renewable Energy Laboratory (NREL), specifically for modeling horizontal-axis wind turbines of different configurations. The ADAMS-code is intended for detailed calculations in the final design stage 318 . Both the subroutine packages AeroDyn (computes the aerodynamic forces for the blades) and YawDyn (blade flap and machine yaw), developed at the University of Utah, can be incorporated in the package 102 . In the 2.0 release, ADAMS WT is limited to fixed- or free yaw, horizontal-axis wind turbines with two-bladed teetering or 3, 4 or 5-bladed rigid hubs BLADED for...

Example The Wind Power Management System

Wind power forecasting is an integral part of the electricity supply system in Germany. The Wind Power Management System developed by ISET is used operationally by three of the four German transmission system operators (see Figure 5.11). The system consists of three parts 1 the online monitoring, which performs an upscaling of online power production measurements at representative wind farms to the total wind power production in a grid area 2 the day-ahead forecast of the wind power production by means of artificial neural networks (ANNs). This is based on input from a numerical weather prediction (NWP) model 3 the short-term forecast, which also employs online wind power measurements to produce an improved forecast for up to eight hours ahead. For a short-term wind power forecast, representative wind farms or wind farm groups have to be determined and equipped with online measurement technology. For the day-ahead forecast, only an historical time series of measured power output of...

Variability in wind power

Non Renewable Energy Sources

An example of short-term variations in wind speed at low height is given in Fig. 3.35. These fluctuations correspond to the region of frequencies above the spectral gap of Fig. 2.110. The occurrences of wind gusts, during which the wind speed may double or drop to half the original value over a fraction of a second, are clearly of importance for the design of wind energy converters. On the other hand, the comparison made in Fig. 3.35 between two simultaneous measurements at distances separated horizontally by 90 m shows that little spatial correlation is present between the short-term fluctuations. Such fluctuations would thus be smoothed out by a wind energy conversion system, which comprises an array of separate units dispersed over a sufficiently large area. The trends in amplitudes of diurnal and yearly wind speed variations are displayed in Fig. 3.36, as functions of height (Petersen, 1974). Such amplitudes are generally site-dependent, as one can deduce, for example, from Figs...

Wind power and backup

Concern has been expressed regarding 'backup' or the additional plant that is needed to offset the variability of renewables, such as wind power. Some authors have suggested that backup equal to 65 per cent of the installed capacity of wind power (PB Power and RAE, 2003), or even 100 per cent of the capacity of wind power (Laughton, 2002 Fells Associates, 2004), would be required to be installed in response to the development of wind power on an electricity network. One method of quantifying the 'backup' requirement of wind power is to compare the capacity credit of wind power to the potential maximum reduction in conventional capacity due to the development of the wind resource. Following on from the scenario presented by Dale et al (2004), a 20 per cent wind power scenario would yield around 80TWh y-1 of wind energy on an equal-generation basis, 80TWh y-1 would be generated by 10.7GW of conventional plant. Ideally, the wind plant would substitute directly for the conventional plant,...

Building Integrated Wind Turbines

There has been considerable interest of late, particularly in Northern Europe, in the possibility of fitting small wind turbines on the roof tops of individual houses. Enthusiasts for this approach claim that small wind turbines sited within the urban environment have the potential to make a significant contribution to the reduction of CO2 levels. A typical wind turbine of this type is illustrated in Figure 8.4. The difficulties facing the designers and manufacturers of such machines are substantial. The dis-economies of downsizing are such that the installation cost per kW of a small wind turbine is considerably more than for a MW size machine. Moreover, the annual average wind speed in a typical urban environment is perhaps one half of that usually experienced in Figure 8.4 Small building integrated wind turbine. (Reproduced with permission of Windsave) Figure 8.4 Small building integrated wind turbine. (Reproduced with permission of Windsave) a good wind farm site. The cubic power...

Main wind turbine modes of operation

Active Stall Blades

In this chapter the main wind turbine modes of operation will be discussed. In general, the following modes of operation can be distinguished 179 In the startup mode the rotor of the wind turbine is accelerated, and the generator is connected to the utility grid. In the power generation mode, power is extracted from the wind and converted to electricity. In this mode the wind velocity ranges from the cut-in wind velocity Vci, via the rated velocity Vr to the cut-out wind velocity Vco as illustrated in Fig. E.1 for a fictive variable rotational speed wind turbine. For the purpose of illustration, the values for Vci, Vr and Vco are 3.0, 12.5 and 25.0 m s respectively for the Lagerwey LW-50 750. In the power generating mode, two different operating areas can be distinguished, viz. partial load (Vci < Vw < Vr) and full load (Vr < Vw < Vco) 36 . In partial load, the aerodynamic (or rotor) power is proportional to the cubic wind velocity. In this operating area maximum energy...

British Wind Energy Association

Windpower Workshop Finally, something to supplant Michael Hackleman's aging classic Wind and Windspinners. Windpower Workshop by Hugh Piggott is a welcome addition to any small wind turbine library and is a must if you want to, as the British say, Do It Yourself. Windpower Workshop is a 1997 release in the Centre for Alternative Technology's series on small wind turbines. For more than twenty years CAT has been demonstrating the use of alternative technology. Windpower Workshop grew out of Hugh's lectures at CAT on how to build low-cost wind machines. The United Kingdom's foremost authority on small wind turbines, Hugh is also the author of CAT's It's a Breeze A Guide to Choosing Windpower, as well as Scrapyard Windpower Realities. The latter, now out of print, was a good hands-on guide to building a small wind turbine from a permanent-magnet generator, a brake drum, and other salvaged auto parts. (Plans for the brake-drum windmill are still available directly from Hugh.) Hugh's book...

Idealised wind energy converter

The considerations outlined throughout this section with regard to assessing the theoretical total capacity extractable by means of wind energy converters (such as a rotor) are based on the following ideal conditions and assumptions - constant, shear-free wind flow (i.e. wind speed is the same at every point of the energy extracting surface (e.g. circular rotor surface SRot) and flows into shaft direction), - free wind flow around the wind energy converter (no external impacts on wind On the basis of the above conditions the maximum physically achievable wind conversion can be derived by a theoretical model that is independent from the technical construction of a wind power station. According to Bernoulli's law, the power contained in every point i of the air flow PWi,i consists of kinetic capacity (1 2 (mW, vWii2)), pressure capacity ((mW,i pwi,i) pwi) and potential capacity which is in this case negligible by approximation. With regard to continuity the wind capacity balance at any...

Small Wind Turbines

For small wind turbines, a measuring program may cost more than the wind turbine therefore, other types of information are needed. As wind maps are developed for potential wind farms by countries, these maps can be used as guides to determine regions with enough wind for small wind turbines. Also, wind maps for countries and large regions obtained from numerical models have sufficient resolution for siting of small wind turbines. Since small wind turbines will be located close to the load, local topography will influence the decision on estimating wind speeds and siting. If the location is on exposed terrain, hills, or ridges, then the wind speeds would be higher than those in the valley. In complex terrain, some sites will be adequate for small wind turbines and other sites will be sheltered. One of the factors in the settlement of the Great Plains of the United States was the farm windmill, which provided water for people and livestock. Therefore, if farm windmills are used or were...

Support mechanisms for wind energy

Historically, electrical energy from wind turbines was not competitive in commercial markets with other forms of generation, particularly the use of a combined cycle gas turbine (CCGT) plant burning natural gas. Hence, in order to take account of external costs, and to meet commitments to reduce CO2 emissions, various support mechanisms have been used by governments to encourage the development of wind power as well as other forms of renewable energy. These support mechanisms, together with the markets for electrical energy, are subject to very rapid change but the main principles are described. Perhaps the most obvious approach to support wind power is to require fixed premium tariffs to be paid for all power generated by renewable sources. This was the basis for the 'Public Utilities Requirement to Purchase Act (PURPA) introduced in the USA in 1978 but abandoned in the late 1980s and the German 'Electricity Feed-in-Law'. A similar approach was adopted in Spain and Denmark for a...

Applications and Wind Industry

The main applications are the generation of electricity and water pumping (Table 10.1). Except for the installed capacity for wind farms, the other numbers are best estimates, as data are difficult to acquire. Applications for generation of electricity are divided into the following categories utility-scale wind farms small wind turbines, which include remote and stand-alone systems distributed wind-diesel village power (generally hybrid systems) and telecommunications (high-reliability hybrid systems). Many village power systems use photovoltaic panels with battery storage, 1 to 3 days. There are wind hybrid systems and some wind power systems for village power. In some cases village power has diesel gas for the backup. Stand-alone systems generally have batteries for storage. There are wind-assist, where two power sources work in parallel to produce power on demand, and stand-alone systems. All wind turbines connected to the utility grid are wind-assist systems. In terms of size,...

Day vs Night Wind Speed Profiles

Comparison of the diurnal (diamonds) and nocturnal (squares) global average profiles of wind speed in 2000 obtained at the sounding stations (with at least 20 valid profiles) with the LS methodology for hub heights in 50-200 m. 5.0 5.5 Wind Speed (m s) Figure 12. Comparison of the diurnal (diamonds) and nocturnal (squares) global average profiles of wind speed in 2000 obtained at the sounding stations (with at least 20 valid profiles) with the LS methodology for hub heights in 50-200 m. wind resource for utility-scale applications (at 30 meters) at mountainous and east-facing locations Elliott et al., 2001c (2) Armenia, represented by only one class-1 station in this study, has excellent wind power potential on top of ridges and in mountain passes Elliott et al., 2003 . Note, however, that all wind atlases cited in this study were obtained for a constant surface roughness of 0.10 m, considerable lower than the values found in the previous section...

Wind Turbine Generator Features

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Percent Increase In Windpower From Ft Reference Height

As the wind passes over the ground, it bumps into trees and houses and passes over hills and valleys. All of this causes friction between the wind and objects on the earth, resulting in the slowing down of the air mass. Because air is a fluid and reacts similarly to water, we can look at a stream to see this phenomenon in action. Water along the bank swirls and eddies around, while the water in the center of the stream keeps moving right along. This swirling action of the wind is called turbulence. What we want to do is minimize this turbulence and allow for the free flow of air past our wind generator rotor. If, on the other hand, we live in a cabin in a five acre clearing in the woods, we have a different problem. Let's assume the cabin is 15 feet high and the trees are at 60 feet. Using the rule of thumb and the generator with a 10 foot rotor, we estimate that we will need a tower about 50 feet high (15 feet + 30 feet + 5 feet) and in the center of the clearing to make the 300 foot...

Generating Electricity Using Wind Power

Experiment 5 examined the fundamentals of three-phase power. The information presented here deals with a principal application of this technology, namely wind power. While solar power is a great choice for localized electricity generation, wind power is certainly the choice for grid-based power generation. Modern wind generators, and the wind farms that host them, can provide large cities like San Francisco and even entire rural states with sufficient power to operate homes and businesses, alike. It has been correctly claimed that if our Midwest states like North and South Dakota were to build mega-wind farms, this flat, barren and constantly windy territory could become the Saudi Arabia of the United States in terms of grid-based wind energy generation. For sometime now counties such as Germany, Spain and Denmark (in order of the percentage of use of wind power) have supplemented their existing fossil and nuclear power generation by the use of wind power. The United States is behind...

Estimated Wind Power for Texas Pacific Northwest Labs

Contour Line Wind Turbines

Pacific Northwest Labs (PNL) estimated the capturable wind power for Texas at 50 m height as 134,000 MW from class 3 and above winds, with 28,000 MW for class 4 winds. Class 4 winds are located primarily in the Panhandle. The PNL estimate was made in the following manner. The total power intercepted over a given land area is a function of the number of wind turbines, the rotor swept area, and the available power in the wind. Environmentally sensitive land, urban areas, and terrain that is in valleys and canyons were excluded. The following formula is used to calculate the power intercepted by the rotor area of the wind turbines where Pa average wind power potential, W m2 At rotor area, n D2 4 D rotor diameter, m and N number of wind turbines. where Ai land area Sr spacing between turbine rows, D and Sc spacing within turbine row, D m2. Note that SrSc is the land area devoted to one turbine. In general, wind plants only remove 3-10 of the land, primarily for roads, from other...

Griddirect Wind Systems

Direct grid-tie, batteryless wind systems are the fastest-growing segment of the U.S. small wind market. This growth is being fueled by demand for simpler, more efficient systems and incentive programs that compensate owners for the amount of energy their system produces. Wind turbines were previously used mostly by off-gridders, but the new market for residential-scale wind turbines is primarily for grid-tie applications. The same arguments for batteryless grid-tied PV systems also apply to wind systems. Additionally, most direct grid-tie turbines are configured for higher voltages than their battery-charging counterparts (typically above 200 VDC, compared to 12 to 48 VDC nominal). These high-voltage turbines allow the use of smaller transmission wiring, which significantly reduces wire and conduit cost. Batteryless wind systems offer an increase in operating efficiency that results in higher overall energy production compared to battery-based systems. Most grid-direct systems use a...

Stateoftheart variable speed wind turbine control

In a variable speed wind turbine, the rotor and the generator are decoupled from the grid by the power electronics implying that the rotor may rotate at (almost) any speed. Consequently, variable speed operation offers more control possibilities than constant rotational speed does. Variable speed operation has two main advantages over constant speed operation i) additional energy capture at partial load and ii) potential reduction of fatigue loads on the structure by absorbing torque fluctuations in the rotor momentum. Other benefits that have been claimed are enhanced utility grid system compatibility, controllable power factor, reduction of acoustic noise at low wind speeds, adaptation to local conditions or compensating for changing conditions, and avoidance of stall over most the operating range 186 . In the context of maximum power extraction in partial load, the effect of variable speed is easily described. The kinetic energy content of the wind passing through the rotor varies...

Scoraig Scotland Brake Drum Wind Power

Scoraig Scotland

One of Hugh's home-built wind generators in Scoraig Scotland. The alternator is built from the brake drum of a truck. A battery charging wind turbine built by Hugh on Scoraig. The dynamo (generator) came from a bus. A battery charging wind turbine built by Hugh on Scoraig. The dynamo (generator) came from a bus. Basically a generator is just a magnet rotor moving past a stationary coil, or vice versa. This results in an alternating voltage in the coil which you can use to produce power. Older wind generators used DC (direct current) generators, which turned the AC to DC using a switching device called a commutator. Modern generators produce AC. If you want DC for charging a battery, you can simply use a solid state rectifier to change AC to DC. High voltage is better in terms of its ability to cover distances. It can be preferable where the wind machine is a long distance from the point of use. In some cases, a 48 volt battery is better than a 12 volt battery, but in other cases it...

Wind Measurement For Small Wind Turbines

For a very small wind turbine of the order of 100 W to 3 kW, the expense of anemometers, data loggers, and the analysis is more than the price of the wind turbine. In one sense, the wind turbine is the anemometer, as the energy produced is the measurement. So you should depend on historical and regional data to determine feasibility of installing a small wind turbine. Two other indicators of feasibility are the past historical use of farm windmills in the area and a check with owners on performance of other small wind turbine installations in the region. For a wind turbine of 10 to 50 kW, the investment is fairly large, 35,000 to 135,000. Inexpensive digital weather stations are now available for 300 to 600, including the data logger, and the data logger can be plugged into a personal computer for analysis. These instruments are not suitable for collecting long-term data for wind resource assessment or for wind farms. If there are wind maps indicating sufficient winds, and if there...

Wind Turbine Installations and Wind Farms

For any wind turbine installation, there are certain additional activities (e.g., construction of foundations and access roads, electrical connections, site erection, as well as project development and management) that must be undertaken. For flat onshore sites, which might be found typically in Denmark or North Germany, the total investment cost is approximately 1.3 times the ex-works turbine cost (EUREC Agency, 1996). In the UK, where sites are often located in more remote, upland areas the balance-of-plant costs (i.e., all costs other than the wind turbines) tend to be higher and a more typical breakdown is shown in Table 9.1. Commercial developers of wind farms will often prefer larger projects as, in that way, the fixed-costs, particularly electrical network connection and project development and management costs, may be spread over a bigger investment. A further encouragement for large projects is that the fixed costs of arranging project finance are high. However, there are...

Differences The effects of wind speed and scheduling procedures

The characteristics of wind tend to be similar the world over and the same applies to electricity networks - but there are some differences. The extra costs of reserve in Great Britain and a number of American electricity jurisdictions are similar (see Figure 2.6) but significantly higher figures are quoted for Germany. This is due partly to the way in which the electricity network is operated, and partly to the lower wind speeds that prevail there. In Germany, as well as in some other electricity jurisdictions, wind tends to be treated in the same way as gas or coal-fired plant and is required to forecast its output several hours ahead. If the plant schedules lack flexibility, it is quite likely that the output from the wind plant will change after the commitment is made. This may mean that balancing power must be purchased to make up any power deficits or, alternatively, surplus wind may need to be sold for a low price. The more flexibility that is built into plant scheduling, the...

No I Hassle Wind Power

Rugged 18 blade Ampair 100 produces up to 100 Watts continuously, 24 Hours per day, at wind speeds from 8 to 100+ mph. No brakes or furling needed guaranteed at any windspeed Veteran of 3 years continuous Antarctic service. Roof mount is OK pole mount is better. Put it up, hook it up to the batteries and forget it Residential Wind Power with Mick Sagrillo, 63 min. Mick Sagrillo has installed and repaired over 1,000 wind turbines.

Wind Resource Screening

As an example, wind resource screening for the Texas Panhandle is presented 25, 26 . The DEM data (3 arc seconds resolution) along with DLG data were used. The original DEM data were in blocks of 1 by 1 . Data for utility transmission lines (69 kW and higher) were input by hand. Two GIS systems, IDRISI and PC ARC INFO, for personal computers were used. IDRISI has built-in functions that enhance its use for wind resource screening slope, hill shading, aspect, and orthographic projection. A data sheet accompanies these functions, which shows bin size, max, min, etc. The Panhandle has a large wind energy potential since it has class 3 and 4 winds over the whole area. On the flat open plains, which describe much of the Panhandle, close to 100 of the area will be in the same wind power class. In this region, wind speed increases with height therefore, modest relief may increase the wind power dramatically. Terrain exposure selects those areas, which are above and below the average...

Average Wind Power Distribution In The United States

At over one thousand locations in the United States, a daily log sheet is filled out with hourly weather observations of the one-minute average wind speed and direction. These records are sent to the National Climatic Center in Asheville, North Carolina, where these one-minute averages for every third hour are entered onto computer magnetic tape. Various monthly and yearly summaries are prepared, and all the original data are stored in archives. Each station receives summaries of its data and these are usually available for inspection (this is described in more detail later in this chapter).

Wind Speed Distribution

Having the cubic relation with the power, the wind speed is the most critical data needed to appraise the power potential of a candidate site. The wind is never steady at any site. It is influenced by the weather system, the local land terrain, and the height above the ground surface. The wind speed varies by the minute, hour, day, season, and year. Therefore, the annual mean speed needs to be averaged over 10 or more years. Such a long term average raises the confidence in assessing the energy-capture potential of a site. However, long-term measurements are expensive, and most projects cannot wait that long. In such situations, the short term, say one year, data is compared with a nearby site having a long term data to predict the long term annual wind speed at the site under consideration. This is known as the measure, correlate and predict (mcp) technique. Since wind is driven by the sun and the seasons, the wind pattern generally repeats over the period of one year. The wind site...

Representative Lease for Wind Farm

For wind farms, the landowner may receive one or more offers, and the leases (Table 12.2) will differ by region, wind resource, and access to transmission. Some landowners are forming associations for dealing with wind farm developers. In the United States, wind turbines can be installed on land currently under the Conservation Reserve Program (CRP) however, there may be a penalty or reimbursement, which is decided by the CRP district. The construction phase of a wind farm project will take from 6 months to a year, while the total development time from selection of land to commission may take up to 6 years (Table 12.3). Wind farms can be installed much faster than transmission lines can be built. Besides the production tax credits, a limiting factor that began in 2008 was that the demand for wind turbines was larger than production, which means lead times for delivery are 2 to 3 years after purchase orders.

Wind Farms At Sea Denmark

In the summer months of 2002 the world's largest offshore wind farm on the Danish west coast was built and put into operation. The sea-based wind farm is sited 14 to 20 kilometers into the North Sea, west of Blavands Huk, and represents the first phase of a large-scale Danish effort to produce non-polluting electricity from these offshore wind turbines. The Horns Rev project, as it is called, has a total capacity of 4000 megawatts and must be established in full before 2030. Figure 6-33 The Horns Rev Danish Wind Farm Figure 6-33 The Horns Rev Danish Wind Farm Historically, wind power capacity has been developed on land, but it has become increasingly difficult to obtain the required permits for turbine sites. With its available coastline, interest has been directed toward coastal areas with shallow water depths between 15 and 50 feet that have the possibility of locating the turbines far enough away from the coast that they are visually neutral, something the Nantucket Sound project...

Wind Farm Performance

Capacity factors have improved with the newer and larger wind turbines, so it is expected that wind farms installed from 2000 on will have better capacity factors than the older installations The early wind farms in California had average capacity factors below 20 , while wind farms in good to excellent wind regimes with new wind turbines should have capacity factors from 35 to 40 . Availability and capacity factor are related, because if the wind turbines are having operational problems, availability and capacity factors will be low. For example, for the first year, there were problems at Horns Rev, an offshore wind farm in Denmark, so the capacity factor was only 26 however, the next year it reached the expected value. At the offshore wind farm Scroby Sands (thirty wind turbines, 60 MW) in the United Kingdom, energy production was limited in the first year of operation. There were numerous mechanical problems, with 27 intermediate-speed and 12 high-speed gearbox bearings replaced,...

Measurement and assessment of power quality characteristics of grid connected wind turbines

Determination of the power quality of wind turbines and prediction of their performance in service is not straightforward and IEC 614200-21 (IEC, 2000b) has been written to provide guidance. There are a number of difficulties when assessing the power quality of wind turbines as their performance will depend on the design of the entire wind turbine (including the aerodynamic rotor and control system), short-circuit level and interpolated for the X R ratio of the point of connection. A weighting factor, based on an assumed Raleigh distribution of wind speed, is also applied to provide flicker coefficients which may be used on sites with various average annual mean wind speeds. The Standard also defines methods to evaluate the impact of wind turbine startup at cut-in and rated wind speeds and during speed changing of two speed generators. Again currents are measured, combined with the 'fictitious grid' to provide a voltage time series and then passed through a flicker algorithm. For...

The Missing Wind Generator

Home Power's 1,000 watt Whisper wind generator, manufactured by World Power Technologies, doesn't really have a proper home in either the 24 or 12 volt system articles. When we wrote the 24 volt system article, the wind genny was charging the 12 volt system. Now it is has been switched over to the 24 VDC system. We made this switch because the 24 VDC system is loaded more heavily than the 12 VDC system. At high output, the LCB is only about 85 percent efficient. But it allows us to transmit maximum wind generator output over a long distance with an acceptable 9 percent voltage drop. The other nice feature of the LCB is that the wind generator's maximum power point can be manually adjusted. During high winds, we dial up the LCB's input voltage, resulting in a higher operating voltage at the wind generator and increased current into the battery.

Wind turbines with vertical rotor axis

Wind wheels and windmills with vertical axes are the oldest systems to exploit the wind. For more than 1000 years drag devices with vertical axes have been constructed. Today there are some modern wind generator concepts that also have vertical axes as shown in Figure 5.11. Rotor concepts with vertical axes are

Where are the wind resources

A recent report by the European Wind Energy Association (EWEA, 2004) provides further material and, with earlier studies, gives estimates of the land-based potential for wind energy development. The total on-land technical potential yield for the 15 European Union member states (EU-15), plus Norway, is given as 649 terawatt hours per year (TWh yr-1).

Offshore wind farms on the transmission grid

As mentioned in Section 3.3.3, energy planning of the Danish Government has scheduled a number of offshore wind farms. According to the plan, the first two will be ready for operation in 2002 - each rated at 150 MW. By the year 2030, 50 of the electrical energy consumption in Denmark will be supplied by wind energy. The Danish power system operators Elkraft System and Eltra are responsible for the integration of these wind farms. Due to their rated power, they will be connected directly to the transmission grid. The specifications for connecting these wind farms are presented (Eltra, 2000). control the production from the wind farm so that it does not exceed a certain MW-value, i.e. a production limit control individually each wind farm have the control to act on the individual wind turbine Furthermore, high wind speed may not cause all the turbines to stop simultaneously. These specifications impose new and challenging demands on the art of wind turbine design. As a new task the...

Figure F Impact of wind technology improvements

The achievement of these research goals would lead to cost reductions that can be viewed from two perspectives. On the one hand, the available land areas for cost-effective machines (i.e., 50 kWh) would be substantially increased. On the other hand, if a wind farm can produce electricity for 50 kWh at a good site, then it can produce electricity for 30 to 40 kWh at better sites. Excellent wind sites, while less common than the good sites, can provide an economic wedge to begin penetration of the generation market in all areas of the country. In the longer term, the issue of facilitating options, such as storage and transmission, might be very important to the success of wind. The availability of cost-effective storage coupled to wind systems would yield capacity credit benefits. In addition, because of its often isolated locations, the value of wind would benefit from transmission distribution access. For example, in the Pacific Northwest, the Bonneville Power Administration (BPA) has...

Wind Technology Utility Sector Case Study

This section presents the results of a feasibility analysis of a proposed installation of a grid-connected wind farm in Denmark. The analyst is seeking to determine whether the project is financially viable. To answer this question, the levelised required revenue of the project over its lifetime is calculated. The levelised required revenue divided by the annual amount of generated electricity is the levelised cost of energy produced by the project. If the levelised cost of energy from the system is less than that for alternative systems, then the projcct io an attractive invcotmcnt. All tcrmo and data input requirements arc explained in the two chapters of this document entitled Utility Sector Financial Analyses and Wind Energy Technology. The analyst has been given a set of performance and cost data for the proposed system by the system designer. These data have been incorporated into the Wind Energy Cost and Performance Parameter Format and presented in Section II below. In Section...

Wind Energy Education

The Fachhochschule Bremerhaven is one of the first universities of applied sciences in Germany that offers a graduate (BSc) programme in wind energy. Says Schulz 'In its first year the course attracted 80 students, a lot more than expected. This autumn (2009) the Fachhochschule commences a Wind Energy Through the WAB network the city also benefits from regional co-operation initiatives. One key example in the field of higher education is the co-operation between the technical universities of Oldenburg, Bremen and Hannover, which together join forces in the ForWind Centre for Wind Energy Research. On a city map Schulz points out the positions of individual wind companies within the Bremerhaven city boundaries. The container harbour is located in the northern part of the city, while the Luneort site - with today's four main offshore wind equipment suppliers - is located in south, and the planned wind equipment terminal is already marked on the map. This map also shows a considerable...

Following in Wind Energys Footsteps

Wind energy is one renewable energy technology developed successfully by mechanical engineers. In the 1970s, wind systems and PV systems started out on nearly the same footing only a few experimental systems for each were installed around the world. Today, there are roughly 10 times more wind energy systems than PV systems installed 50,000 MW of wind systems versus 5,000 MW of PV systems. Why were wind energy technologies able to surpass PV systems One reason was that wind developers were able to quickly demonstrate economies of production just as a market opportunity appeared. The state of California offered long-term standard-offer contracts from 1985 to 1989 to purchase the electricity over 20 years from large-scale renewable energy projects. These long-term contracts were similar in many ways to the successful European feed-in tariffs. Solar concentrators producing heat to drive electric generators called concentrating solar power (CSP) systems also took advantage of the...

Total extra costs of wind energy

The total extra costs of operating an electricity network with increasing amounts of wind are now of considerable interest due to the recent increases in the price of gas. The differences between the generation costs from wind and those from gas are narrowing, and it is quite likely that wind energy might become cheaper. The total extra costs of wind energy take into account the following During the last two or three years, several analyses have appeared that quantify the additional costs (if any) to electricity consumers of increasing the amount of renewables - especially wind energy - in the generation mix. Examples include an analysis for the UK (Dale et al, 2004), and for Pennsylvania (Black and Veatch Corporation, 2004). The latter suggested that a 10 per cent renewables portfolio by 2015 would increase costs by US 0.4 MWh. Wind contributed about 65 per cent of the renewables mix. The UK analysis suggested that the extra cost to the electricity consumer of providing 20 per cent...

Effect of wind farm power output forecasting

Short-term forecasting of wind farm output has been worked on for more than 15 years within the wind industry (see Chapter 5 and Giebel et al, 2003). It has a function in contributing to making wind more predictable. This allows for the conventional plants to plan ahead to adjust their output appropriately. During earlier years, it was largely of interest to grid operators. More recently, the owners of wind farms have also been taking an interest for two reasons. First, in some regions they are obliged to provide forecasts of output by the grid operator. Second, in some markets there is recognition that the power produced may be of more value if an accurate forecast were available. The period of 1 hour ahead to 72 hours ahead is what is normally technically feasible. For an example forecast, see Figure 10.7. Figure 10.7 A typical 24-hour (ahead) wind power forecast and the corresponding actual generation

Wind Power In The United States And Southern Canada

The following table lists the wind power at 750 stations in the United States and Southern Canada. The data in the table have been extracted from the report Wind Power Climatology in the United States by Jack Reed of Sandia Laboratories, Albuquerque, New Mexico (June 1975). This report (SAND 74-0348) can be ordered from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Road, Springfield, VA 22151. A printed copy costs 7.60 and a microfiche copy costs 2.25 (see if your local library has a microfiche reader). Besides the data in this table, the report contains average monthly results for each station of the percentage of time the velocity was in each of about eight speed ranges, i.e. 6. Average wind speed in knots (multiply by 1.15 to convert to mph, Vave 7- Twelve average monthly wind power values in watts per MONTHLY AVERAGE WIND POWER IN Tl MONTHLY AVERAGE WIND POWER IN Tl

Wind Farms as a Tourist Attraction

Windmill Tours of Palm Springs, California has hit upon a unique and fun way to learn about wind power. As the ad says Travel through a forest of towering windmills on electric-powered vehicles. Feel the energy as the giant blades WHOOSH overhead. Your skilled guide will take you inside this working wind farm comprised of turbines modernized to efficiently contribute to a cleaner and safer environment. As you travel along the 90-minute adventure, you realize the environmentally friendly power propelling experience was created by the air you are breathing.

Wind speed analysis probability and prediction

Implementation of wind power requires knowledge of future wind speed at the turbine sites. Such information is essential for the design of the machines and the energy systems, and for the economics. The seemingly random nature of wind and the site-specific characteristics makes such information challenging, yet much can be done from statistical analysis, from correlation of measurement time-series and from meteorology. The development of wind power has led to great sophistication in the associated analysis, especially involving data handling techniques and computer modelling. However, Example 9.1 and Table 9.3 illustrate the principles of such analysis, by showing how the power available from the wind at a particular site can be calculated from very basic measured data on the distribution of wind speed at that site. Commercial measurement techniques are more sophisticated, but the principles are the same. Example 9.1 Wind speed analysis for the island of North Ronaldsay,

The role of wind power in providing capacity

1 Maximum conventional capacity requirement. With the addition of renewable generating capacity, the total conventional capacity requirement can only stay the same or fall it cannot increase. For example, if wind power is added to a network that currently requires 84 gigawatts (GW) of plant to meet demand the total conventional plant requirement will not exceed 84GW because of the development of wind power. In the example above, the landfill gas capacity would have a capacity credit of 100 per cent since it has substituted directly for an equivalent amount of conventional capacity on the network. Variable-output renewables such as wind power have a limited capacity credit as their probability of generation at times of peak demand is lower than that for conventional or dispatchable renewable capacity. Two recent studies have attempted to clarify the question of whether wind power provides capacity on electricity networks one reviewing 29 separate studies (UKERC, 2006, summarized in...

Wind power in Costa Rica

In Costa Rica a significant private-sector wind power industry has emerged (Martinot, 2002). Apparently, early project preparation activities, including institutional and technical feasibility studies, have engendered favourable perceptions and regulatory frameworks for wind (including 'iron-clad' power purchase agreements). Regulatory frameworks in Costa Rica, technology perceptions, and studies addressing non-technical issues have probably been more important than mitigation of perceptions of technical risk through hardware demonstrations.

Estimated Wind Power for Texas Alternative Energy Institute

The same procedures of terrain enhancement and GIS were used to estimate the capturable wind power for Texas 27 . The selection criteria were wind class 3 or higher from revised wind map using terrain exposure, slope of 0-3 , excluded lands (urban, highways, federal and state parks, lakes, wildlife refuges, and federal wetlands), and within 15 km of transmission lines (115 kV and above). The capturable annual power was calculated for the following conditions for the wind turbines 50 m hub height, 10D by 10D spacing, 30 capacity factor, and no array losses (reasonable since the spacing is large). With these assumptions, the estimated annual capturable wind power was 157,000 MW (525,000 MW of wind turbines at 30 efficiency) with an annual energy production of 1,300 TWh. These results are somewhat larger than the estimates determined by PNL. FIGURE 9.9 Wind power map for Texas, 1995. FIGURE 9.9 Wind power map for Texas, 1995. lands increased. The selection parameters were the same,...

Benefits Of Wind Power

Wind power is primarily a utility-scale technology, with hundreds of turbines arrayed in large wind farms. Wind offers a number of advantages over fossil fuel in powering the grid Electric power from wind in most cases is already cheaper than power from natural gas, coal, and nuclear plants. Even locations that do not have adequate wind resources can benefit from wind generation elsewhere, which helps to hold down grid power costs overall. Like solar and geothermal power, most of the costs are up front to build a wind system. After that, the maintenance and operation costs are minimal and predictable. So financing wind-power projects can be low-risk compared to fossil-fueled plants, where the cost of the fuel is volatile and unpredictable, and thus an investment risk. Deploying more wind reduces climate change. Once in place, a wind farm creates no greenhouse gas emissions. Wind power needs no water. Traditional power plants of all kinds require significant amounts of water, as much...

Applications of wind power forecasting

The most important application for wind power forecasting is to reduce the need for balancing energy and reserve power, which are needed to integrate wind power within the balancing of supply and demand in the electricity supply system (i.e. to optimize power plant scheduling). This leads to lower integration costs for wind power, lower emissions from the power plants used for balancing, and, subsequently, to a higher value of wind power. A second application is to provide forecasts of wind power feed-in for grid operation and grid security evaluation. To assess the security of the grid and to operate it (e.g. for maintenance and repair), the grid operator needs to know the current and future wind power feed-in at each grid connection point. The objectives of a wind power forecast therefore depend upon the application For optimized power plant scheduling and power balancing, an accurate forecast of the wind power generation for the whole control zone is needed. The relevant time...

Demand growth scenarios with various penetration levels of wind energy by

Growth Wind Penetration

As already referred to, the problem to be faced in the future is how to accommodate high levels of variable wind capacity in a power supply system if security of supply considerations (i.e. capacity credit limitations) do not allow the release of alternative conventional generation capacity. This situation is illustrated in the results of a study for the UK Department of Trade and Industry (DTI) (ILEX Energy Consulting, 2002), in which future demands were postulated along with a high degree of penetration of wind power capacity. The results are shown in Table 1.3. Table 1.3 High electricity demand growth scenarios considered for Great Britain with various penetration levels of wind energy by 2020 Table 1.3 High electricity demand growth scenarios considered for Great Britain with various penetration levels of wind energy by 2020 Installed wind capacity (MW) Wind Capacity Installed GW Figure 1.14 Wind capacity credit in Great Britain relative to the National Grid security of supply...

Costs for a wind power plant with return on capital

Adapting the example of the 1500 kW wind power plant (A0 1,800,000 Ai 50,000 q 1.08 n 20 Ea 3.5 106 kWhel) to an interest rate of ir 8 per cent yields A high number of privately financed wind power projects have been built in the past few years in Germany. Many projects have been realized with 30 per cent equity capital. The remainder of the investment has come from bank loans with relatively low interest rates in the range of 5 per cent. Project risks such as incorrect yield calculations or changes in the wind resources are borne by the equity investor. Therefore, higher interest rates are assumed here.

Fraunhofer Wind Energy Institute

Other news presented by Nick Leptin included a report on the founding of a new Bremerhaven-based Fraunhofer Centre for Wind Energy and Maritime Technology that became operational early 2009. The initiative aims at concentrating the country's wind power-related R& D infrastructure into one specialized research body. In his closing statement Leptin clearly voiced concerns over plans to pool renewable resources at a European level saying 'We are sceptical about these plans, specifically out of fear for a strong bureaucratic organizational structure. A centralized research body comprising 26 European member states simply cannot function effectively.'

Estimating Wind Resources at Your Site

Wind Estimating Guide

Wind can be a difficult resource to estimate. For one thing, wind resources are extremely site dependent. The U.S. Department of Energy has compiled wind resource maps that are available from the American Wind Energy Association and the National Technical Information Service. These maps are excellent sources for regional information and can show whether wind speeds in your area are generally strong enough to justify further investigations. Checking with your local airport or weather bureau will help give you an idea of the wind speeds in your area, but your site may experience higher or lower average wind Average Annual Wind Power Resource Wind Speed speeds. Your site should have average wind speeds of at least nine miles per hour or more. If you do not have on-site data and want to obtain a clearer, more predictable picture of your wind resource, you may wish to measure wind speeds at your site for a year. You can do this with a recording anemometer. The most accurate readings are...

Of Wind Power In The

Ago and weren't very good to begin with. Now they will give you more bad information than good. The best book was Wind Energy, How to Use It by Paul Gipe, but you will be lucky to find a copy of this out-of-print paperback. Another good one was Wind Power for the Homeowner by Donald Marier, which may still be available through Rodale Press or in your local library. For diehards, an international magazine Wind Power Monthly is available for 50 yr from The best way to keep current with the progress of wind energy development, both small and large scale, in the U.S. is to join the American Wind Energy A 35 year individual membership brings a newsletter and an opportunity to help push legislation to promote the increased use of wind energy and other renewables. Author Michael Bergey, Bergey Windpower, Inc., 2001 Priestley Avenue, Norman, OK 73069 405-364-4212.

Wind Project Development

The three most important considerations for development of wind farms are 1. Land with good to excellent wind resource The American Wind Energy Association 11, 12 and Wind Powering America 13 also have information on project development. The project development list covers many areas however, it was placed in economics, as that is the final decision on a project. Much of the information was from Disgen 14 . 1.1. Evidence of significant wind resource 2.2. Rights Wind rights, ingress egress rights, transmission right-of-way for wind farm 2.7 Bond to remove wind turbines at end of project 2.8 Wind energy easements, legal issues 3. Wind resource assessment 3.4. Collect 10 min or an hour of wind speed and direction data, 1-2 years, minimum 1 year The following example shows the main points of a contract signed by the Permanent University Fund, State of Texas, for a Woodward Mountain wind farm (32 MW) near McCamey (year 2000).

Siting for Wind Farms

The number of met stations and the time period for data collection to predict the energy production for a wind farm vary depending on the terrain and the availability of long-term base data in the vicinity. In general, numerical models of wind flow will predict wind speeds to within 5 for relatively flat terrain and 10 for complex terrain, which means an error in energy of 15-30 . Therefore, a wind measurement program is imperative before a wind farm is installed. However, if a number of wind farms are already in the region, then 1 year of data collection might suffice. For complex terrain, you may need one met station per three to five wind turbines. For wind turbines of 500 kW to megawatts, you may need a met station per one or two wind turbines in complex terrain. With more homogeneous terrain, as in the Plains, a primary tall met station and one to four smaller met stations may suffice. The tallest met station should be a representative location on the wind farm area, not the best...

Box Two highprofile environmentalists debate wind power

The following newswire excerpt of an AAP news story illustrates how anti-wind power activists can capture media attention Two prominent international environmentalists are butting heads over whether wind farms should be set up across Australia. Renowned British botanist David Bellamy has become a strident anti-wind farm activist, denouncing them as pointless, expensive, ugly and dangerous to birds He has called the advocates of wind-generated power liars and in an Australian newspaper recently described wind farms as 'weapons of mass destruction'. Now Canadian geneticist, broadcaster and environmental guru David Suzuki has attacked Bellamy's stance, saying it makes no sense. 'To call wind turbines weapons of mass destruction is unscientific, irresponsible and simply wrong,' he said in a statement. 'Wind farms are about the most environmentally benign energy sources we have - they literally create electricity from fresh air.' The spat between Suzuki and Bellamy over Australian power...

Other Wind Farms in the United States

Wind farms generated an estimated 26.3 TWh in 2006, and some capacity factors were over 40 6 . The capacity factor (Figure 8.5) and specific output (Figure 8.6) were analyzed for four wind farms (Table 8.2) in the Southern High Plains, same wind turbine, but with smaller rotor diameter and hub height for White Deer and part of Fluvana. Capacity factors ranged from 33 to 45 , and the largest annual specific output was 1,350 kWh m2. The yearly variation is the same across the region however, the slight downtrend in capacity factor at White Deer may be due to a decline in reliability. Manufacturers are now offering wind turbines with different sized rotors for different wind regimes. For Texas, estimated energy output would improve with an increase of the wind turbine rotor diameter by 8 , rather than increasing hub height from 75 m to 100 m. FIGURE 8.4 Specific output for manufacturers with largest installed capacity, California. NEG-Micon wind turbines are larger and do not include the...

Wind Speed and Energy Distributions

The wind turbine captures the wind's kinetic energy in a rotor consisting of two or more blades mechanically coupled to an electrical generator. The turbine is mounted on a tall tower to enhance the energy capture. Numerous wind turbines are installed at one site to build a wind farm of the desired power production capacity. Obviously, sites with steady high wind produce more energy over the year. Two distinctly different configurations are available for the turbine design, the horizontal axis configuration (Figure 4-1) and the vertical axis configuration (Figure 4-2). The vertical axis machine has the shape of an egg beater, and is often called the Darrieus rotor after its inventor. It has been used in the past because of specific structural advantage. However, most modern wind turbines use horizontal-axis design. Except for the rotor, all other components are the same in both designs, with some difference in their placement.

Rating of Visual Impact of Small Wind Turbines

Viewpoint and 18 for the public viewpoint. If the score (Table 9.2) is below the significant range, the wind turbine is unlikely to have a visual impact unless it is close to and at the center of a scenic view. The score is only a general indicator for visual impact of small wind turbines. Wind turbines will be visible, at least from some viewpoints, as they will be above surrounding trees. In the Plains areas with few trees, small wind turbines will be noticeable from 1 to 3 km, the same as the trees around a farmhouse. Notice that there are comparable-height towers, such as cell phone towers, towers for lights at highway interchanges, radio towers, and the long rows of towers for utility transmission lines. The difference is that those towers do not have moving rotors.

Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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