Sample records for rated wind speed

  1. The Effect of Wind Speed and Electric Rates On Wind Turbine Economics

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    The Effect of Wind Speed and Electric Rates On Wind Turbine Economics Economics of wind power depends mainly on the wind speeds and the turbine make and model. Definition: Simple Payback The "Simple period of a small wind power project. All the figures are per turbine, so it can be used for a one, two

  2. IMPROVED MICROWAVE REMOTE SENSING OF HURRICANE WIND SPEED AND RAIN RATES USING THE HURRICANE IMAGING RADIOMETER (HIRAD)

    E-Print Network [OSTI]

    Ruf, Christopher

    IMPROVED MICROWAVE REMOTE SENSING OF HURRICANE WIND SPEED AND RAIN RATES USING THE HURRICANE) that measures wind speed and rain rate along the ground track directly beneath the aircraft. This paper presents are presented, which illustrate wind speed and rain rate measurement spatial resolutions and swath coverage. 1

  3. HURRICANE IMAGING RADIOMETER WIND SPEED AND RAIN RATE RETRIEVAL: [PART-1] DEVELOPMENT OF AN IMPROVED OCEAN

    E-Print Network [OSTI]

    Ruf, Christopher

    HURRICANE IMAGING RADIOMETER WIND SPEED AND RAIN RATE RETRIEVAL: [PART-1] DEVELOPMENT U.S.A * selnimri@mail.ucf.edu 2 NOAA/AOML/Hurricane Research Division, Miami, Florida, USA 3 Space model has been developed to support the analysis and design of the new airborne Hurricane Imaging

  4. Dual-speed wind turbine generation

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P. [National Renewable Energy Lab., Golden, CO (United States)] [National Renewable Energy Lab., Golden, CO (United States); Handman, D. [Flowind Corp., San Rafael, CA (United States)] [Flowind Corp., San Rafael, CA (United States)

    1996-10-01T23:59:59.000Z

    Induction generator has been used since the early development of utility-scale wind turbine generation. An induction generator is the generator of choice because of its ruggedness and low cost. With an induction generator, the operating speed of the wind turbine is limited to a narrow range (almost constant speed). Dual- speed operation can be accomplished by using an induction generator with two different sets of winding configurations or by using a dual output drive train to drive two induction generators with two different rated speeds. With single-speed operation, the wind turbine operates at different power coefficients (Cp) as the wind speed varies. Operation at maximum Cp can occur only at a single wind speed. However, if the wind speed.varies across a wider range, the operating Cp will vary significantly. Dual-speed operation has the advantage of enabling the wind turbine to operate at near maximum Cp over a wider range of wind speeds. Thus, annual energy production can be increased. The dual-speed mode may generate less energy than a variable-speed mode; nevertheless, it offers an alternative which captures more energy than single-speed operation. In this paper, dual-speed operation of a wind turbine is investigated. Annual energy production is compared between single-speed and dual-speed operation. One type of control algorithm for dual-speed operation is proposed. Some results from a dynamic simulation will be presented to show how the control algorithm works as the wind turbine is exposed to varying wind speeds.

  5. VARIABLE SPEED WIND TURBINE

    E-Print Network [OSTI]

    Chatinderpal Singh

    Wind energy is currently the fastest-growing renewable source of energy in India; India is a key market for the wind industry, presenting substantial opportunities for both the international and domestic players. In India the research is carried out on wind energy utilization on big ways.There are still many unsolved challenges in expanding wind power, and there are numerous problems of interest to systems and control researchers. In this paper we study the pitch control mechanism of wind turbine. The pitch control system is one of the most widely used control techniques to regulate the output power of a wind turbine generator. The pitch angle is controlled to keep the generator power at rated power by reducing the angle of the blades. By regulating, the angle of stalling, fast torque changes from the wind will be reutilized. It also describes the design of the pitch controller and discusses the response of the pitch-controlled system to wind velocity variations. The pitch control system is found to have a large output power variation and a large settling time.

  6. Estimation of Wind Speed in Connection to a Wind Turbine

    E-Print Network [OSTI]

    Estimation of Wind Speed in Connection to a Wind Turbine X. Ma #3; , N. K. Poulsen #3; , H. Bindner y December 20, 1995 Abstract The wind speed varies over the rotor plane of wind turbine making the wind speed on the rotor plane will be estimated by using a wind turbine as a wind measuring device

  7. Dynamic simulation of dual-speed wind turbine generation

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P.

    1996-10-01T23:59:59.000Z

    Induction generators have been used since the early development of utility-scale wind turbine generation. An induction generator is the generator of choice because of its ruggedness, and low cost. With an induction generator, the operating speed of the wind turbine is limited to a narrow range (almost constant speed). Dual- speed operation can be accomplished by using an induction generator with two different sets of winding configurations or by using two induction generators with two different rated speeds. With single- speed operation, the wind turbine operates at different power coefficients (Cp) as the wind speed varies. The operation at maximum Cp can occur only at a single wind speed. However, if the wind speed varies across a wider range, the operating Cp will vary significantly. Dual-speed operation has the advantage of enabling the wind turbine to operate at near maximum Cp over a wider range of wind-speeds. Thus, annual energy production can be increased. The dual-speed mode may generate less energy than a variable-speed mode; nevertheless, it offers an alternative to capture more energy than single-speed operation. In this paper, dual-speed operation of a wind turbine will be investigated. One type of control algorithm for dual- speed operation is proposed. Results from a dynamic simulation will be presented to show how the control algorithm works and how power, current and torque of the system vary as the wind turbine is exposed to varying wind speeds.

  8. Numerical wind speed simulation model

    SciTech Connect (OSTI)

    Ramsdell, J.V.; Athey, G.F.; Ballinger, M.Y.

    1981-09-01T23:59:59.000Z

    A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared.

  9. Wind Speed Forecasting for Power System Operation 

    E-Print Network [OSTI]

    Zhu, Xinxin

    2013-07-22T23:59:59.000Z

    In order to support large-scale integration of wind power into current electric energy system, accurate wind speed forecasting is essential, because the high variation and limited predictability of wind pose profound challenges to the power system...

  10. Wind Speed Forecasting for Power System Operation

    E-Print Network [OSTI]

    Zhu, Xinxin

    2013-07-22T23:59:59.000Z

    In order to support large-scale integration of wind power into current electric energy system, accurate wind speed forecasting is essential, because the high variation and limited predictability of wind pose profound challenges to the power system...

  11. LIDAR Wind Speed Measurements of Evolving Wind Fields

    SciTech Connect (OSTI)

    Simley, E.; Pao, L. Y.

    2012-07-01T23:59:59.000Z

    Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feedforward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. Past studies have assumed Taylor's frozen turbulence hypothesis, which implies that turbulence remains unchanged as it advects downwind at the mean wind speed. With Taylor's hypothesis applied, the only source of wind speed measurement error is distortion caused by the LIDAR. This study introduces wind evolution, characterized by the longitudinal coherence of the wind, to LIDAR measurement simulations to create a more realistic measurement model. A simple model of wind evolution is applied to a frozen wind field used in previous studies to investigate the effects of varying the intensity of wind evolution. LIDAR measurements are also evaluated with a large eddy simulation of a stable boundary layer provided by the National Center for Atmospheric Research. Simulation results show the combined effects of LIDAR errors and wind evolution for realistic turbine-mounted LIDAR measurement scenarios.

  12. Quantifying hurricane wind speed with undersea sound

    E-Print Network [OSTI]

    Wilson, Joshua David

    2006-01-01T23:59:59.000Z

    Hurricanes, powerful storms with wind speeds that can exceed 80 m/s, are one of the most destructive natural disasters known to man. While current satellite technology has made it possible to effectively detect and track ...

  13. Simulation of wind-speed time series for wind-energy conversion analysis.

    SciTech Connect (OSTI)

    Corotis, R.B.

    1982-06-01T23:59:59.000Z

    In order to investigate operating characteristics of a wind energy conversion system it is often desirable to have a sequential record of wind speeds. Sometimes a long enough actual data record is not available at the time an analysis is needed. This may be the case if, e.g., data are recorded three times a day at a candidate wind turbine site, and then the hourly performance of generated power is desired. In such cases it is often possible to use statistical characteristics of the wind speed data to calibrate a stochastic model and then generate a simulated wind speed time series. Any length of record may be simulated by this method, and desired system characteristics may be studied. A simple wind speed simulation model, WEISIM, is developed based on the Weibull probability distribution for wind speeds with a correction based on the lag-one autocorrelation value. The model can simulate at rates from one a second to one an hour, and wind speeds can represent short-term averages (e.g., 1-sec averages) or longer-term averages (e.g., 1-min or 1 hr averages). The validity of the model is verified with PNL data for both histogram characteristics and persistance characteristics.

  14. Wind speed PDF classification using Dirichlet mixtures Rudy CALIF1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Wind speed PDF classification using Dirichlet mixtures Rudy CALIF1 , Richard EMILION2 , Ted'Orléans), UMR CNRS 6628 Université d'Orléans, France. Abstract: Wind energy production is very sensitive to instantaneous wind speed fluctuations. Thus rapid variation of wind speed due to changes in the local

  15. Pitch-controlled variable-speed wind turbine generation

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P.

    2000-03-01T23:59:59.000Z

    Wind energy is a viable option to complement other types of pollution-free generation. In the early development of wind energy, the majority of wind turbines were operated at constant speed. Recently, the number of variable-speed wind turbines installed in wind farms has increased and more wind turbine manufacturers are making variable-speed wind turbines. This paper covers the operation of variable-speed wind turbines with pitch control. The system the authors considered is controlled to generate maximum energy while minimizing loads. The maximization of energy was only carried out on a static basis and only drive train loads were considered as a constraint. In medium wind speeds, the generator and power converter control the wind turbine to capture maximum energy from the wind. In the high wind speed region, the wind turbine is controlled to maintain the aerodynamic power produced by the wind turbine. Two methods to adjust the aerodynamic power were investigated: pitch control and generator load control, both of which are employed to control the operation of the wind turbine. The analysis and simulation shows that the wind turbine can be operated at its optimum energy capture while minimizing the load on the wind turbine for a wide range of wind speeds.

  16. 1. Wind-splash erosion 4. Relationships between rainfall intensity, wind-speed, wind direction and erosion

    E-Print Network [OSTI]

    from the surface but unless it corresponds to a high wind-speed (the potential to transport a single rainfall event. When high wind-speeds and heavy rainfall combine there is an increased potential1. Wind-splash erosion 4. Relationships between rainfall intensity, wind-speed, wind direction

  17. Probabilistic Wind Speed Forecasting Using Ensembles and Bayesian Model Averaging

    E-Print Network [OSTI]

    Raftery, Adrian

    the chance of winds high enough to pose dangers for boats or aircraft. In situations calling for a cost/loss analysis, the probabilities of different outcomes need to be known. For wind speed, this issue often arisesProbabilistic Wind Speed Forecasting Using Ensembles and Bayesian Model Averaging J. Mc

  18. Spatial and Temporal Patterns of Global Onshore Wind Speed Distribution

    SciTech Connect (OSTI)

    Zhou, Yuyu; Smith, Steven J.

    2013-09-09T23:59:59.000Z

    Wind power, a renewable energy source, can play an important role in electrical energy generation. Information regarding wind energy potential is important both for energy related modeling and for decision-making in the policy community. While wind speed datasets with high spatial and temporal resolution are often ultimately used for detailed planning, simpler assumptions are often used in analysis work. An accurate representation of the wind speed frequency distribution is needed in order to properly characterize wind energy potential. Using a power density method, this study estimated global variation in wind parameters as fitted to a Weibull density function using NCEP/CFSR reanalysis data. The estimated Weibull distribution performs well in fitting the time series wind speed data at the global level according to R2, root mean square error, and power density error. The spatial, decadal, and seasonal patterns of wind speed distribution were then evaluated. We also analyzed the potential error in wind power estimation when a commonly assumed Rayleigh distribution (Weibull k = 2) is used. We find that the assumption of the same Weibull parameter across large regions can result in substantial errors. While large-scale wind speed data is often presented in the form of average wind speeds, these results highlight the need to also provide information on the wind speed distribution.

  19. Observed and CAM3 GCM Sea Surface Wind Speed Distributions: Characterization, Comparison, and Bias Reduction

    E-Print Network [OSTI]

    Capps, Scott B; Zender, Charles S

    2008-01-01T23:59:59.000Z

    bin predictions. and 90th percentile wind speeds and higherWind speed mean, 90th percentile, standard deviation, andwind speed mean, 90th percentile, standard deviation, and

  20. The wind speed profile at offshore wind farm sites Bernhard Lange(1)

    E-Print Network [OSTI]

    Heinemann, Detlev

    The wind speed profile at offshore wind farm sites Bernhard Lange(1) , Søren E. Larsen(2) , Jørgen in Europe will come from offshore sites. The first large offshore wind farms are #12;currently being built feasibility of offshore wind power utilisation depends on the favourable wind conditions offshore compared

  1. Analytical Modelling of Wind Speed Deficit in Large Offshore Wind Farms

    E-Print Network [OSTI]

    Pryor, Sara C.

    Analytical Modelling of Wind Speed Deficit in Large Offshore Wind Farms Sten Frandsen*, Rebecca areas.As is often the need for offshore wind farms, the model handles a regular array geometry for offshore wind farms, the model handles a priori a regular array geometry with straight rows of wind

  2. 0 Riso-R-434 Wind Speed and Direction

    E-Print Network [OSTI]

    meteorological statistics for the area as it was considered a possible site for a nuclear power plant. \\ \\ Duringm I 0 Riso-R-434 t Wind Speed and Direction Changes due to Terrain Effects revealed-4000 Roskilde, Denmark May 1983 #12;RISÃ?-R-434 WIND SPEED AND DIRECTION CHANGES DUE TO TERRAIN EFFECTS

  3. Probability distributions of land surface wind speeds over North America

    E-Print Network [OSTI]

    Dai, Aiguo

    . Jones, A. Dai, S. Biner, D. Caya, and K. Winger (2010), Probability distributions of land surface wind distribution used for estimation of wind climate and annual winProbability distributions of land surface wind speeds over North America Yanping He,1 Adam Hugh

  4. MODELLING THE VERTICAL WIND SPEED AND TURBULENCE INTENSITY PROFILES AT PROSPECTIVE OFFSHORE WIND FARM SITES

    E-Print Network [OSTI]

    Heinemann, Detlev

    in Europe will come from offshore sites. The first large offshore wind farms are currently being builtMODELLING THE VERTICAL WIND SPEED AND TURBULENCE INTENSITY PROFILES AT PROSPECTIVE OFFSHORE WIND for conditions important for offshore wind energy utilisation are compared and tested: Four models

  5. MODELLING THE VERTICAL WIND SPEED AND TURBULENCE INTENSITY PROFILES AT PROSPECTIVE OFFSHORE WIND FARM SITES

    E-Print Network [OSTI]

    Heinemann, Detlev

    MODELLING THE VERTICAL WIND SPEED AND TURBULENCE INTENSITY PROFILES AT PROSPECTIVE OFFSHORE WIND important for offshore wind energy utilisation are discussed and tested: Four models for the surface tested with data from the offshore field measurement Rødsand by extrapolating the measured 10 m wind

  6. Q: When planning a wind farm, how are wind resources estimated? And if the average wind speed is known at 10 meters is there a general rule for estimating the wind speed at

    E-Print Network [OSTI]

    Q: When planning a wind farm, how are wind resources estimated? And if the average wind speed is known at 10 meters is there a general rule for estimating the wind speed at larger heights above ground level? The wind resource at a wind farm can be estimated in two ways: by measurement or by modeling

  7. Microsoft Word - idaho_wind_speed_summary.doc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ft. Hall, ID Sites Wheat Grass Ridge Average Wind Speeds Site 0001 (66 ft. (20m) tower, erected week of 11101, data started on 11201) N. 42 deg. 44.762', W. 112 deg. 41.011'...

  8. Microsoft Word - utah_wind_speed_summary.doc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    02 - 110502) 10.6 mph Overall Average (120101 - 110502) 7.8 mph Dean Davis Site Spanish Fork, Utah Average Wind Speeds Site 0009 (66 ft. (20m) tower, data started on 1101...

  9. Ris-R-Report LIDAR Wind Speed Measurements from a

    E-Print Network [OSTI]

    the approaching wind fields from this vantage point. Time series of wind speed measurements from the lidar with 50: Time series of the yaw misalignment 67 #12;4 Risø-R-1741(EN) Preface Mikael Rasmussen and Per Hansen is acknowledged for safety supervision of the operation of the NM80 research turbine. The Spin

  10. Variable speed operation of generators with rotor-speed feedback in wind power applications

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P.; Migliore, P.

    1995-11-01T23:59:59.000Z

    The use of induction generators in wind power applications has been common since the early development of the wind industry. Most of these generators operate at fixed frequency and are connected directly to the utility grid. Unfortunately, this mode of operation limits the rotor speed to a specific rpm. Variable-speed operation is preferred in order to facilitate maximum energy capture over a wide range of wind speeds. This paper explores variable-speed operating strategies for wind turbine applications. The objectives are to maximize energy production, provide controlled start-up and reduce torque loading. This paper focuses on optimizing the energy captured by operating at maximum aerodynamic efficiency at any wind speed. The control strategy we analyze uses rotor speed and generator power as the feedback signals. In the normal operating region, rotor speed is used to compute a target power that corresponds to optimum operation. With power as the control objective, the power converter and generator are controlled to track the target power at any rpm. Thus, the torque-speed characteristic of the generator is shaped to optimize the energy capture. The target power is continuously updated at any rpm. in extreme areas of the operating envelope, during start-up, shutdown, generator overload, or overspeed, different strategies driven by other system considerations must be used.

  11. Variable speed operation of generators with rotor-speed feedback in wind power applications

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P.; Migliore, P. [National Renewable Energy Lab., Golden, CO (United States). Wind Technology Div.

    1996-10-01T23:59:59.000Z

    The use of induction generators in wind power applications has been common since the early development of the wind industry. Most of these generators operate at fixed frequency and are connected directly to the utility grid. Unfortunately, this mode of operation limits the rotor speed to a specific rpm. Variable-speed operation is preferred in order to facilitate maximum energy capture over a wide range of wind speeds. This paper explores variable-speed operating strategies for wind turbine applications. The objectives are to maximize energy production, provide controlled start-up and reduce torque loading. This paper focuses on optimizing the energy captured by operating at maximum aerodynamic efficiency at any wind speed. The control strategy analyzed uses rotor speed and generator power as the feedback signals. In the normal operating region, rotor speed is used to compute a target power that corresponds to optimum operation. With power as the control objective, the power converter and generator are controlled to track the target power at any rpm. Thus, the torque-speed characteristic of the generator is shaped to optimize the energy capture. The target power is continuously updated at any rpm. In extreme areas of the operating envelope, during start-up, shutdown, generator overload, or overspeed, different strategies driven by other system considerations must be used.

  12. Variable speed operation of generators with rotor-speed feedback in wind power applications

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P.; Migliore, P. [National Renewable Energy Lab., Golden, CO (United States)

    1996-11-01T23:59:59.000Z

    The use of induction generators in wind power applications has been common since the early development of the wind industry. Most of these generators operate at fixed frequency and are connected directly to the utility grid. Unfortunately, this mode of operation limits the rotor speed to a specific rpm. Variable speed operation is preferred in order to facilitate maximum energy capture over a wide range of wind speeds. This paper explores variable speed operating strategies for wind turbine applications. The objectives are to maximize energy production, provide controlled start-up, and reduce torque loading. This paper focuses on optimizing the energy captured by operating at maximum aerodynamic efficiency at any wind speed. The control strategy the authors analyze uses rotor speed and generator power as the feedback signals. In the normal operating region, rotor speed is used to compute a target power that corresponds to optimum operation. With power as the control objective, the power converter and generator are controlled to track the target power at any rpm. Thus, the torque-speed characteristic of the generator is shaped to optimize the energy capture. The target power is continuously updated at any rpm. In extreme areas of the operating envelope, during start-up, shutdown, generator overload, or overspeed, different strategies driven by other system considerations must be used.

  13. The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle

    E-Print Network [OSTI]

    Richardson, John

    The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle Matthias R. Aellig Alamos National Lab., Los Alamos, NM 87545 Abstract We investigate the helium abundance in the solar wind of 1994 and early 2000 are analyzed. In agreement with similar work for previous solar cycles, we find

  14. Observed and CAM3 GCM Sea Surface Wind Speed Distributions: Characterization, Comparison, and Bias Reduction

    E-Print Network [OSTI]

    Capps, Scott B; Zender, Charles S

    2008-01-01T23:59:59.000Z

    341–345. Yuan, X. , 2004: High-wind-speed evaluation in theCosca, 2004: Effects of wind speed and gas exchange param-dust emission caused by wind erosion. J. Geophys. Res. ,

  15. MEASUREMENT OF WIND SPEED FROM COOLING LAKE THERMAL IMAGERY

    SciTech Connect (OSTI)

    Garrett, A; Robert Kurzeja, R; Eliel Villa-Aleman, E; Cary Tuckfield, C; Malcolm Pendergast, M

    2009-01-20T23:59:59.000Z

    The Savannah River National Laboratory (SRNL) collected thermal imagery and ground truth data at two commercial power plant cooling lakes to investigate the applicability of laboratory empirical correlations between surface heat flux and wind speed, and statistics derived from thermal imagery. SRNL demonstrated in a previous paper [1] that a linear relationship exists between the standard deviation of image temperature and surface heat flux. In this paper, SRNL will show that the skewness of the temperature distribution derived from cooling lake thermal images correlates with instantaneous wind speed measured at the same location. SRNL collected thermal imagery, surface meteorology and water temperatures from helicopters and boats at the Comanche Peak and H. B. Robinson nuclear power plant cooling lakes. SRNL found that decreasing skewness correlated with increasing wind speed, as was the case for the laboratory experiments. Simple linear and orthogonal regression models both explained about 50% of the variance in the skewness - wind speed plots. A nonlinear (logistic) regression model produced a better fit to the data, apparently because the thermal convection and resulting skewness are related to wind speed in a highly nonlinear way in nearly calm and in windy conditions.

  16. The amount of power in the wind is very dependent on the speed of the wind. Because the power in the wind

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    the potential benefits of a wind power installation, wind speeds and other characteristics of a site's wind for potential wind power sites. However, these maps do not elimi- nate the need for more precise and thoroughThe amount of power in the wind is very dependent on the speed of the wind. Because the power

  17. ARE660 Wind Generator: Low Wind Speed Technology for Small Turbine Development

    SciTech Connect (OSTI)

    Robert W. Preus; DOE Project Officer - Keith Bennett

    2008-04-23T23:59:59.000Z

    This project is for the design of a wind turbine that can generate most or all of the net energy required for homes and small businesses in moderately windy areas. The purpose is to expand the current market for residential wind generators by providing cost effective power in a lower wind regime than current technology has made available, as well as reduce noise and improve reliability and safety. Robert W. Preus’ experience designing and/or maintaining residential wind generators of many configurations helped identify the need for an improved experience of safety for the consumer. Current small wind products have unreliable or no method of stopping the wind generator in fault or high wind conditions. Consumers and their neighbors do not want to hear their wind generators. In addition, with current technology, only sites with unusually high wind speeds provide payback times that are acceptable for the on-grid user. Abundant Renewable Energy’s (ARE) basic original concept for the ARE660 was a combination of a stall controlled variable speed small wind generator and automatic fail safe furling for shutdown. The stall control for a small wind generator is not novel, but has not been developed for a variable speed application with a permanent magnet alternator (PMA). The fail safe furling approach for shutdown has not been used to our knowledge.

  18. EVALUATION OF MODELS FOR THE VERTICAL EXTRAPOLATION OF WIND SPEED MEASUREMENTS AT OFFSHORE SITES

    E-Print Network [OSTI]

    Heinemann, Detlev

    sites. The first large offshore wind farms are currently being built in several countries in Europe. For the planning of offshore wind farms the vertical wind speed profile is needed for two main reasons: WindEVALUATION OF MODELS FOR THE VERTICAL EXTRAPOLATION OF WIND SPEED MEASUREMENTS AT OFFSHORE SITES

  19. Probability distributions for offshore wind speeds Eugene C. Morgan a,*, Matthew Lackner b

    E-Print Network [OSTI]

    Vogel, Richard M.

    Probability distributions for offshore wind speeds Eugene C. Morgan a,*, Matthew Lackner b Wind turbine energy output Weibull distribution Extreme wind a b s t r a c t In planning offshore wind farms, short-term wind speeds play a central role in estimating various engi- neering parameters

  20. Improvements in wind speed forecasts for wind power prediction purposes using Kalman filtering

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Improvements in wind speed forecasts for wind power prediction purposes using Kalman filtering P : 10.1016/j.jweia.2008.03.013 #12;2 Abstract This paper studies the application of Kalman filtering forecasts. The application of Kalman filter to these data leads to the elimination of any possible

  1. Hi-Q Rotor - Low Wind Speed Technology

    SciTech Connect (OSTI)

    Todd E. Mills; Judy Tatum

    2010-01-11T23:59:59.000Z

    The project objective was to optimize the performance of the Hi-Q Rotor. Early research funded by the California Energy Commission indicated the design might be advantageous over state-of-the-art turbines for collecting wind energy in low wind conditions. The Hi-Q Rotor is a new kind of rotor targeted for harvesting wind in Class 2, 3, and 4 sites, and has application in areas that are closer to cities, or 'load centers.' An advantage of the Hi-Q Rotor is that the rotor has non-conventional blade tips, producing less turbulence, and is quieter than standard wind turbine blades which is critical to the low-wind populated urban sites. Unlike state-of-the-art propeller type blades, the Hi-Q Rotor has six blades connected by end caps. In this phase of the research funded by DOE's Inventions and Innovation Program, the goal was to improve the current design by building a series of theoretical and numeric models, and composite prototypes to determine a best of class device. Development of the rotor was performed by aeronautical engineering and design firm, DARcorporation. From this investigation, an optimized design was determined and an 8-foot diameter, full-scale rotor was built and mounted using a Bergey LX-1 generator and furling system which were adapted to support the rotor. The Hi-Q Rotor was then tested side-by-side against the state-of-the-art Bergey XL-1 at the Alternative Energy Institute's Wind Test Center at West Texas State University for six weeks, and real time measurements of power generated were collected and compared. Early wind tunnel testing showed that the cut-in-speed of the Hi-Q rotor is much lower than a conventional tested HAWT enabling the Hi-Q Wind Turbine to begin collecting energy before a conventional HAWT has started spinning. Also, torque at low wind speeds for the Hi-Q Wind Turbine is higher than the tested conventional HAWT and enabled the wind turbine to generate power at lower wind speeds. Based on the data collected, the results of our first full-scale prototype wind turbine proved that higher energy can be captured at lower wind speeds with the new Hi-Q Rotor. The Hi-Q Rotor is almost 15% more productive than the Bergey from 6 m/s to 8 m/s, making it ideal in Class 3, 4, and 5 wind sites and has application in the critical and heretofore untapped areas that are closer to cities, 'load centers,' and may even be used directly in urban areas. The additional advantage of the Hi-Q Rotor's non-conventional blade tips, which eliminates most air turbulence, is noise reduction which makes it doubly ideal for populated urban areas. Hi-Q Products recommends one final stage of development to take the Hi-Q Rotor through Technology Readiness Levels 8-9. During this stage of development, the rotor will be redesigned to further increase efficiency, match the rotor to a more suitable generator, and lower the cost of manufacturing by redesigning the structure to allow for production in larger quantities at lower cost. Before taking the rotor to market and commercialization, it is necessary to further optimize the performance by finding a better generator and autofurling system, ones more suitable for lower wind speeds and rpms should be used in all future testing. The potential impact of this fully developed technology will be the expansion and proliferation of energy renewal into the heretofore untapped Class 2, 3, 4, and 5 Wind Sites, or the large underutilized sites where the wind speed is broken by physical features such as mountains, buildings, and trees. Market estimates by 2011, if low wind speed technology can be developed are well above: 13 million homes, 675,000 commercial buildings, 250,000 public facilities. Estimated commercial exploitation of the Hi-Q Rotor show potential increase in U.S. energy gained through the clean, renewable wind energy found in low and very low wind speed sites. This new energy source would greatly impact greenhouse emissions as well as the public sector's growing energy demands.

  2. United States- Land Based and Offshore Annual Average Wind Speed at 100 Meters

    Broader source: Energy.gov [DOE]

    Full-size, high resolution version of the 100-meter land-based and offshore wind speed resource map.

  3. Control strategy of a variable speed wind turbine with multipole permanent magnet synchronous generator

    E-Print Network [OSTI]

    values. Keywords: permanent magnet synchronous generator, variable speed wind turbine, direct driven wind). A multipole synchronous generator connected to a power converter can operate at low speeds, so that a gear canControl strategy of a variable speed wind turbine with multipole permanent magnet synchronous

  4. Observed and CAM3 GCM Sea Surface Wind Speed Distributions: Characterization, Comparison, and Bias Reduction

    E-Print Network [OSTI]

    Zender, Charles

    resources force the use of coarse-resolution GCMs, which do not resolve finer-scale wind speed fluctuationsObserved and CAM3 GCM Sea Surface Wind Speed Distributions: Characterization, Comparison, and Bias (Manuscript received 10 December 2007, in final form 8 April 2008) ABSTRACT Climatological surface wind speed

  5. Wind speed influence on phytoplankton bloom dynamics in the Southern Ocean Marginal Ice Zone

    E-Print Network [OSTI]

    Fitch, Dillon T; Moore, J. Keith

    2007-01-01T23:59:59.000Z

    Niebauer, H. J. (1982), Wind and melt driven circulation inJ. K. Moore (2007), Wind speed influence on phytoplanktonby the NASA Ocean Vector Winds Science Team. Data are

  6. Solar wind-magnetosphere coupling leading to relativistic electron energization during high-speed streams

    E-Print Network [OSTI]

    Lyons, Larry

    Solar wind-magnetosphere coupling leading to relativistic electron energization during high. Smith (2005), Solar wind-magnetosphere coupling leading to relativistic electron energization during. Using observations during a period of persistent high-speed, corotating, solar wind streams, we

  7. Ris-PhD-Report Accounting for the speed shear in wind

    E-Print Network [OSTI]

    Risø-PhD-Report Accounting for the speed shear in wind turbine power performance measurement Rozenn for the speed shear in wind turbine power performance measurement Division: Wind Energy Division Abstract: The power curve of a wind turbine is the primary char- acteristic of the machine as it is the basis

  8. Empirical downscaling of wind speed probability distributions S. C. Pryor and J. T. Schoof1

    E-Print Network [OSTI]

    Pryor, Sara C.

    . Barthelmie2 Department of Wind Energy and Atmospheric Physics, Risø National Laboratory, Roskilde, Denmark decreases in mean wind speed, 90th percentile wind speed, and energy density in 2071­2100 relative to 1961 increase in the annual wind energy resource over northern Europe between the end of the 20th century

  9. Laboratory implementation of variable-speed wind turbine generation

    SciTech Connect (OSTI)

    Zinger, D.S. [Northern Illinois University, DeKalb, IL (United States)] [Northern Illinois University, DeKalb, IL (United States); Miller, A.A. [Univ. of Idaho, Moscow, ID (United States)] [Univ. of Idaho, Moscow, ID (United States); Muljadi, E.; Butterfield, C.P.; Robinson, M.C. [National Renewable Energy Lab., Golden, CO (United States)] [National Renewable Energy Lab., Golden, CO (United States)

    1996-07-01T23:59:59.000Z

    To improve the performance of wind turbines, various control schemes such as variable speed operation have been proposed. Testing of these control algorithms on a full scale system is very expensive. To test these systems simulation, we developed programs and small scale laboratory experiments. We used this system to verify a control method that attempts to keep the turbine operating at its peak power coefficient. Both the simulations and the experiments verified the principle of operation of this control scheme.

  10. EFFECT OF PITCH CONTROL AND POWER CONDITIONING ON POWER QUALITY OF VARIABLE SPEED WIND TURBINE GENERATORS

    E-Print Network [OSTI]

    EFFECT OF PITCH CONTROL AND POWER CONDITIONING ON POWER QUALITY OF VARIABLE SPEED WIND TURBINE), Curtin University of Technology, WA Abstract: Variable speed wind turbine generators provide the opportunity to capture more power than fixed speed turbines. However the variable speed machine output can

  11. Systematic Controller Design Methodology for Variable-Speed Wind Turbines

    SciTech Connect (OSTI)

    Hand, M. M.; Balas, M. J.

    2002-02-01T23:59:59.000Z

    Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three operational regions. This paper provides a guide for controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship between the two opposing metrics is easily visualized.

  12. Relationship Between Solar Wind Speed and Coronal Magnetic Field Properties

    E-Print Network [OSTI]

    Fujiki, Ken'ichi; Iju, Tomoya; Hakamada, Kazuyuki; Kojima, Masayoshi

    2015-01-01T23:59:59.000Z

    We have studied the relationship between the solar-wind speed $[V]$ and the coronal magnetic-field properties (a flux expansion factor [$f$] and photospheric magnetic-field strength [$B_{\\mathrm{S}}$]) at all latitudes using data of interplanetary scintillation and solar magnetic field obtained for 24 years from 1986 to 2009. Using a cross-correlation analyses, we verified that $V$ is inversely proportional to $f$ and found that $V$ tends to increase with $B_{\\mathrm{S}}$ if $f$ is the same. As a consequence, we find that $V$ has extremely good linear correlation with $B_{\\mathrm{S}}/f$. However, this linear relation of $V$ and $B_{\\mathrm{S}}/f$ cannot be used for predicting the solar-wind velocity without information on the solar-wind mass flux. We discuss why the inverse relation between $V$ and $f$ has been successfully used for solar-wind velocity prediction, even though it does not explicitly include the mass flux and magnetic-field strength, which are important physical parameters for solar-wind accele...

  13. Control strategy for variable-speed, stall-regulated wind turbines

    SciTech Connect (OSTI)

    Muljadi, E.; Pierce, K.; Migliore, P.

    1998-04-01T23:59:59.000Z

    A variable-speed, constant-pitch wind turbine was investigated to evaluate the feasibility of constraining its rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades from the wind was manipulated. Specifically, the blades were caused to stall in high winds. In low and moderate winds, the demanded generator torque and the resulting rotor speed were controlled to cause the wind turbine to operate near maximum efficiency. A computational model was developed, and simulations were conducted of operation in high turbulent winds. Results indicated that rotor speed and power output were well regulated. 7 refs., 7 figs.

  14. Tip Jets and Barrier Winds: A QuikSCAT Climatology of High Wind Speed Events around Greenland

    E-Print Network [OSTI]

    Renfrew, Ian

    of Environmental Sciences, University of East Anglia, Norwich, United Kingdom (Manuscript received 28 September meteorological, oceanographic, cli- matological, and wind energy applications. Strong sur- face winds overTip Jets and Barrier Winds: A QuikSCAT Climatology of High Wind Speed Events around Greenland G. W

  15. Sandia National Laboratories: wind turbines produce rated power

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wind turbines produce rated power Increasing the Scaled Wind Farm Technology Facility's Power Production On April 7, 2014, in Energy, Facilities, News, News & Events, Partnership,...

  16. Measurement strategies for estimating long-term average wind speeds

    SciTech Connect (OSTI)

    Ramsdell, J.V.; Houston, S.; Wegley, H.L.

    1980-10-01T23:59:59.000Z

    The uncertainty and bias in estimates of long-term average wind speeds inherent in continuous and intermittent measurement strategies are examined by simulating the application of the strategies to 40 data sets. Continuous strategies have smaller uncertainties for fixed duration measurement programs, but intermittent strategies make more efficient use of instruments and have smaller uncertainties for a fixed amount of instrument use. Continuous strategies tend to give biased estimates of the long-term annual mean speed unless an integral number of years' data is collected or the measurement program exceeds 3 years in duration. Intermittent strategies with three or more month-long measurement periods per year do not show any tendency toward bias.

  17. A sea drag relation for hurricane wind speeds N. C. Zweers,1

    E-Print Network [OSTI]

    Vries, Hans de

    A sea drag relation for hurricane wind speeds N. C. Zweers,1 V. K. Makin,1 J. W. de Vries,1 and G, the surface drag is overestimated in NWP models for hurricane wind speeds and the intensity of hurricane winds is tested in an NWP model. Two hurricanes in the Caribbean are modeled: Ivan (2004) and Katrina (2005

  18. Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems

    E-Print Network [OSTI]

    Boyer, Edmond

    Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems B. Beltran, T. Ahmed power generation in variable speed wind energy conversion systems (VS-WECS). These systems have two variations. Index Terms--Wind energy conversion system, power generation control, sliding mode control

  19. Modelling and Analysis of Variable Speed Wind Turbines with Induction Generator during Grid

    E-Print Network [OSTI]

    Hansen, René Rydhof

    Modelling and Analysis of Variable Speed Wind Turbines with Induction Generator during Grid Fault to the grid connection of wind turbines. The second chapter elucidates recent thinking in the area of grid Risø National Laboratory Vestas Wind Systems A/S #12;#12;I Modelling and Analysis of Variable Speed

  20. Interpolating wind speed normals from the sparse Dutch network to a high resolution

    E-Print Network [OSTI]

    Stoffelen, Ad

    , we had potential wind speed time series with 30 years of data (with at least 20 yearly and monthly by Verkaik (Verkaik, 2001). The method is a five-step procedure: 1 Use series of (potential) wind to calculate (potential) normals at measuring sites 2 Calculate wind speed normals at the top of the surface

  1. WINDSAT RETRIEVAL OF OCEAN SURFACE WIND SPEEDS IN TROPICAL CYCLONES Amanda Mims, Rachael Kroodsma, Christopher Ruf, Darren McKague

    E-Print Network [OSTI]

    Ruf, Christopher

    of emissivity on wind speed up to category 3 hurricane-force winds. 1. INTRODUCTION The microwave emissivity and horizontally polarized emissivity versus wind speed at hurricane force winds. 2. SATELLITE AND GROUNDBASEDWINDSAT RETRIEVAL OF OCEAN SURFACE WIND SPEEDS IN TROPICAL CYCLONES Amanda Mims, Rachael Kroodsma

  2. Effects of turbulence on power generation for variable-speed wind turbines

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C.P.; Buhl, M.L. Jr.

    1996-11-01T23:59:59.000Z

    One of the primary advantages of variable-speed wind turbines over fixed-speed turbines should be improved aerodynamic efficiency. With variable-speed generation, in order to maintain a constant ratio of wind speed to tip speed, the wind turbine changes rotor speed as the wind speed changes. In this paper we compare a stall-controlled, variable-speed wind turbine to a fixed-speed turbine. The focus of this paper is to investigate the effects of variable speed on energy capture and its ability to control peak power. We also show the impact of turbulence on energy capture in moderate winds. In this report, we use a dynamic simulator to apply different winds to a wind turbine model. This model incorporates typical inertial and aerodynamic performance characteristics. From this study we found a control strategy that makes it possible to operate a stall-controlled turbine using variable speed to optimize energy capture and to control peak power. We also found that turbulence does not have a significant impact on energy capture.

  3. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, E.

    1998-08-25T23:59:59.000Z

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility. 14 figs.

  4. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-01-01T23:59:59.000Z

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  5. Variable Speed Wind Turbine Generator with Zero-sequence Filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-08-25T23:59:59.000Z

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  6. Low Wind Speed Turbine Development Project Report: November 4, 2002 - December 31, 2006

    SciTech Connect (OSTI)

    Mikhail, A.

    2009-01-01T23:59:59.000Z

    This report summarizes work conducted by Clipper Windpower under the DOE Low Wind Speed Turbine project. The objective of this project was to produce a wind turbine that can lower the cost of energy.

  7. Offshore Coastal Wind Speed Gradients: issues for the design and development of large offshore windfarms

    E-Print Network [OSTI]

    Pryor, Sara C.

    -situ and remote sensing data from offshore wind farms in Denmark, are used to examine both horizontal and vertical the area of the wind farm appear to be small and negligible. 1. INTRODUCTION As large offshore wind farmsOffshore Coastal Wind Speed Gradients: issues for the design and development of large offshore

  8. The effect of wind speed fluctuations on the performance of a wind-powered membrane system for brackish water desalination 

    E-Print Network [OSTI]

    Park, Gavin L.; Schäfer, Andrea; Richards, Bryce S.

    2011-01-01T23:59:59.000Z

    A wind-powered reverse osmosis membrane (wind-membrane) system without energy storage was tested using synthetic brackish water (2750 and 5500 mg/L NaCl) over a range of simulated wind speeds under both steady-state and ...

  9. Low Wind Speed Turbine Developments in Convoloid Gearing: Final Technical Report, June 2005 - October 2008

    SciTech Connect (OSTI)

    Genesis Partners LP

    2010-08-01T23:59:59.000Z

    This report presents the results of a study conducted by Genesis Partners LP as part of the United States Department of Energy Wind Energy Research Program to develop wind technology that will enable wind systems to compete in regions having low wind speeds. The purpose of the program is to reduce the cost of electricity from large wind systems in areas having Class 4 winds to 3 cents per kWh for onshore systems or 5 cents per kWh for offshore systems. This work builds upon previous activities under the WindPACT project, the Next Generation Turbine project, and Phase I of the Low Wind Speed Turbine (LWST) project. This project is concerned with the development of more cost-effective gearing for speed increasers for wind turbines.

  10. Master's thesis: "Wind speed measurements in an offshore wind farm by remote sensing: Comparison of radar satellite TerraSAR-X and ground-based

    E-Print Network [OSTI]

    Peinke, Joachim

    Master's thesis: "Wind speed measurements in an offshore wind farm by remote sensing: Comparison of the Offshore wind farm alpha ventus with 12 wind turbines, substation and met mast Fino1. Southerly winds cause (wake) caused by wind farms and especially for the interaction of large offshore wind farms, which can

  11. Low Wind Speed Technology Phase II: Investigation of the Application of Medium-Voltage Variable-Speed Drive Technology to Improve the Cost of Energy from Low Wind Speed Turbines; Behnke, Erdman and Whitaker Engineering, Inc.

    SciTech Connect (OSTI)

    Not Available

    2006-03-01T23:59:59.000Z

    This fact sheet describes a subcontract with Behnke, Erdman & Whitaker Engineering, Inc. to test the feasibility of applying medium-voltage variable-speed drive technology to low wind speed turbines.

  12. Low Wind Speed Turbine Project Phase II: The Application of Medium-Voltage Electrical Apparatus to the Class of Variable Speed Multi-Megawatt Low Wind Speed Turbines; 15 June 2004--30 April 2005

    SciTech Connect (OSTI)

    Erdman, W.; Behnke, M.

    2005-11-01T23:59:59.000Z

    Kilowatt ratings of modern wind turbines have progressed rapidly from 50 kW to 1,800 kW over the past 25 years, with 3.0- to 7.5-MW turbines expected in the next 5 years. The premise of this study is simple: The rapid growth of wind turbine power ratings and the corresponding growth in turbine electrical generation systems and associated controls are quickly making low-voltage (LV) electrical design approaches cost-ineffective. This report provides design detail and compares the cost of energy (COE) between commercial LV-class wind power machines and emerging medium-voltage (MV)-class multi-megawatt wind technology. The key finding is that a 2.5% reduction in the COE can be achieved by moving from LV to MV systems. This is a conservative estimate, with a 3% to 3.5% reduction believed to be attainable once purchase orders to support a 250-turbine/year production level are placed. This evaluation considers capital costs as well as installation, maintenance, and training requirements for wind turbine maintenance personnel. Subsystems investigated include the generator, pendant cables, variable-speed converter, and padmount transformer with switchgear. Both current-source and voltage-source converter/inverter MV topologies are compared against their low-voltage, voltage-source counterparts at the 3.0-, 5.0-, and 7.5-MW levels.

  13. A conservative control strategy for variable-speed stall-regulated wind turbines

    SciTech Connect (OSTI)

    Muljadi, E.; Pierce, K.; Migliore, P.

    2000-02-08T23:59:59.000Z

    Simulation models of a variable-speed, fixed-pitch wind turbine were investigated to evaluate the feasibility of constraining rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades from the wind was manipulated. Specifically, the blades were caused to stall in high winds. In low and moderate winds, the demanded generator torque and the resulting rotor speed were controlled to cause the wind turbine to operate near maximum efficiency. Using the developed models, simulations were conducted of operation in turbulent winds. Results indicated that rotor speed and power output were well regulated. Preliminary investigations of system dynamics showed that, compared to fixed-speed operation, variable-speed operation caused cyclic loading amplitude to be reduced for the turbine blades and low-speed shaft and slightly increased for the tower loads. This result suggests a favorable impact on fatigue life from implementation of the proposed control strategy.

  14. Solar-wind magnetosphere coupling, including relativistic electron energization, during high-speed streams

    E-Print Network [OSTI]

    Lyons, Larry

    Solar-wind­ magnetosphere coupling, including relativistic electron energization, during high. If this inference is correct, and if it is chorus that energizes the relativistic electrons, then high-speed solar-speed solar wind streams, and fluxes of relativistic electrons observed at geosynchronous orbit enhance

  15. An examination of loads and responses of a wind turbine undergoing variable-speed operation

    SciTech Connect (OSTI)

    Wright, A.D.; Buhl, M.L. Jr.; Bir, G.S.

    1996-11-01T23:59:59.000Z

    The National Renewable Energy Laboratory has recently developed the ability to predict turbine loads and responses for machines undergoing variable-speed operation. The wind industry has debated the potential benefits of operating wind turbine sat variable speeds for some time. Turbine system dynamic responses (structural response, resonance, and component interactions) are an important consideration for variable-speed operation of wind turbines. The authors have implemented simple, variable-speed control algorithms for both the FAST and ADAMS dynamics codes. The control algorithm is a simple one, allowing the turbine to track the optimum power coefficient (C{sub p}). The objective of this paper is to show turbine loads and responses for a particular two-bladed, teetering-hub, downwind turbine undergoing variable-speed operation. The authors examined the response of the machine to various turbulent wind inflow conditions. In addition, they compare the structural responses under fixed-speed and variable-speed operation. For this paper, they restrict their comparisons to those wind-speed ranges for which limiting power by some additional control strategy (blade pitch or aileron control, for example) is not necessary. The objective here is to develop a basic understanding of the differences in loads and responses between the fixed-speed and variable-speed operation of this wind turbine configuration.

  16. SCALAR WIND SPEED AND DIRECTION TROPICAL CYCLONE RETRIEVALS FOR CONICAL SCANNING SCATTEROMETERS

    E-Print Network [OSTI]

    Hennon, Christopher C.

    SCALAR WIND SPEED AND DIRECTION TROPICAL CYCLONE RETRIEVALS FOR CONICAL SCANNING SCATTEROMETERS--Scatterometer measurements of ocean vector winds (OVW) are significantly degraded in the presence of the precipitation, especially in tropical cyclones. This paper presents a new ocean hurricane/typhoon wind vector retrieval

  17. An aero-elastic flutter based electromagnetic energy harvester with wind speed augmenting funnel

    E-Print Network [OSTI]

    Stanford University

    An aero-elastic flutter based electromagnetic energy harvester with wind speed augmenting funnel been used to convert wind flow energy into mechanical vibration, which is then transformed-scale renewable energy generating systems such as wind turbines, thermal generators, and solar panels, energy

  18. EVALUATION OF MODELS FOR THE VERTICAL EXTRAPOLATION OF WIND SPEED MEASUREMENTS AT OFFSHORE SITES

    E-Print Network [OSTI]

    Heinemann, Detlev

    will come from offshore sites. The first large offshore wind farms are currently being built in severalEVALUATION OF MODELS FOR THE VERTICAL EXTRAPOLATION OF WIND SPEED MEASUREMENTS AT OFFSHORE SITES important for offshore wind energy utilisation are discussed and tested: Four models for the surface

  19. Individual Pitch Control for Mitigation of Power Fluctuation of Variable Speed Wind Turbines

    E-Print Network [OSTI]

    Hu, Weihao

    Individual Pitch Control for Mitigation of Power Fluctuation of Variable Speed Wind Turbines, China mcheng@seu.edu.cn Abstract-- Grid connected wind turbines are the sources of power fluctuations presents an individual pitch control (IPC) strategy to mitigate the wind turbine power fluctuation at both

  20. LIDAR Wind Speed Measurement Analysis and Feed-Forward Blade Pitch Control for Load Mitigation in Wind Turbines: January 2010--January 2011

    SciTech Connect (OSTI)

    Dunne, F.; Simley, E.; Pao, L.Y.

    2011-10-01T23:59:59.000Z

    This report examines the accuracy of measurements that rely on Doppler LIDAR systems to determine their applicability to wind turbine feed-forward control systems and discusses feed-forward control system designs that use preview wind measurements. Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feed-forward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. The first half of this report examines the accuracy of different measurement scenarios that rely on coherent continuous-wave or pulsed Doppler LIDAR systems to determine their applicability to feed-forward control. In particular, the impacts of measurement range and angular offset from the wind direction are studied for various wind conditions. A realistic case involving a scanning LIDAR unit mounted in the spinner of a wind turbine is studied in depth with emphasis on choices for scan radius and preview distance. The effects of turbulence parameters on measurement accuracy are studied as well. Continuous-wave and pulsed LIDAR models based on typical commercially available units were used in the studies present in this report. The second half of this report discusses feed-forward control system designs that use preview wind measurements. Combined feedback/feed-forward blade pitch control is compared to industry standard feedback control when simulated in realistic turbulent above-rated winds. The feed-forward controllers are designed to reduce fatigue loads, increasing turbine lifetime and therefore reducing the cost of energy. Three feed-forward designs are studied: non-causal series expansion, Preview Control, and optimized FIR filter. The input to the feed-forward controller is a measurement of incoming wind speeds that could be provided by LIDAR. Non-causal series expansion and Preview Control methods reduce blade root loads but increase tower bending in simulation results. The optimized FIR filter reduces loads overall, keeps pitch rates low, and maintains rotor speed regulation and power capture, while using imperfect wind measurements provided by the spinning continuous-wave LIDAR model.

  1. Abstract--A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous

    E-Print Network [OSTI]

    Chen, Zhe

    1 Abstract--A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous generators (MPMSGs) drive-train configuration is employed in the wind turbine of this variable speed wind turbine based on multiple generators drive-train configuration. Index Terms--Wind power

  2. Euler-Bernoulli Implementation of Spherical Anemometers for High Wind Speed Calculations via Strain Gauges

    E-Print Network [OSTI]

    Castillo, Davis

    2011-08-08T23:59:59.000Z

    avenues for these environments from the traditional cup model to sonar, hot-wire, and recent developments with sphere anemometers. Several measurement methods have modeled the air drag force as a quadratic function of the corresponding wind speed...

  3. annual wind speeds: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In this paper, an efficient system has been presented comprising of solar panel, wind generator, charge controller and charge storage unit (battery). Solar panel is selected as...

  4. accurate wind speed: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    In this paper, an efficient system has been presented comprising of solar panel, wind generator, charge controller and charge storage unit (battery). Solar panel is selected as...

  5. THE HURRICANE IMAGING RADIOMETER WIDE SWATH SIMULATION AND WIND SPEED RETRIEVALS

    E-Print Network [OSTI]

    Ruf, Christopher

    THE HURRICANE IMAGING RADIOMETER WIDE SWATH SIMULATION AND WIND SPEED RETRIEVALS Ruba A. Amarin1 Space Flight Center, Huntsville, Alabama 4 NOAA/AOML/Hurricane Research Division, Miami, Florida, USA ABSTRACT The knowledge of peak winds in hurricanes is critical to classification of hurricane intensity

  6. Tuesday, 31 July, 2012 Rapid radiation belt losses occurring during high speed solar wind stream1

    E-Print Network [OSTI]

    Otago, University of

    Tuesday, 31 July, 2012 1 Rapid radiation belt losses occurring during high speed solar wind stream1 Raita11 Sodankylä Geophysical Observatory, University of Oulu, Sodankylä, Finland12 Abstract. Recent geomagnetic disturbances triggered by the arrival of a Solar14 Wind Stream Interface (SWSI). In the current

  7. HIGH-SPEED AXIAL-FLUX PERMANENT MAGNET MICROMOTORS WITH ELECTROPLATED WINDINGS

    E-Print Network [OSTI]

    the other. The folded-coil stator fabrication process is detailed, followed by the motor driver topology- plated multi-phase stator windings and their use in a high-speed permanent magnet micromotor. As the stator windings of an axial- flux micromotor, both single-plated folded coils, and two-layer double

  8. UNIVERSITY OF CALIFORNIA, Surface Wind Speed Distributions: Implications for Climate and Wind Power

    E-Print Network [OSTI]

    Zender, Charles

    and Wind Power DISSERTATION submitted in partial satisfaction of the requirements for the degree of DOCTOR . . . . . . . . . . . . . . . . . 19 1.3 Global Ocean Wind Power and Surface Layer Stability . . . . . . . . 23 1.3.1 Global Winds . . . . . . 27 1.4 Usable Offshore Wind Power . . . . . . . . . . . . . . . . . . . . . . . 31 1.4.1 Wind Turbine

  9. Euler-Bernoulli Implementation of Spherical Anemometers for High Wind Speed Calculations via Strain Gauges 

    E-Print Network [OSTI]

    Castillo, Davis

    2011-08-08T23:59:59.000Z

    New measuring methods continue to be developed in the field of wind anemometry for various environments subject to low-speed and high-speed flows, turbulent-present flows, and ideal and non-ideal flows. As a result, anemometry has taken different...

  10. Space-time forecasting and evaluation of wind speed with statistical tests for comparing accuracy of spatial predictions

    E-Print Network [OSTI]

    Hering, Amanda S.

    2010-10-12T23:59:59.000Z

    High-quality short-term forecasts of wind speed are vital to making wind power a more reliable energy source. Gneiting et al. (2006) have introduced a model for the average wind speed two hours ahead based on both spatial and temporal information...

  11. Fixed-Speed and Variable-Slip Wind Turbines Providing Spinning Reserves to the Grid: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Singh, M.; Gevorgian, V.

    2012-11-01T23:59:59.000Z

    As the level of wind penetration increases, wind turbine technology must move from merely generating power from wind to taking a role in supporting the bulk power system. Wind turbines should have the capability to provide inertial response and primary frequency (governor) response so they can support the frequency stability of the grid. To provide governor response, wind turbines should be able to generate less power than the available wind power and hold the rest in reserve, ready to be accessed as needed. This paper explores several ways to control wind turbine output to enable reserve-holding capability. This paper focuses on fixed-speed (also known as Type 1) and variable-slip (also known as Type 2) turbines.

  12. CONSTRAINING HIGH-SPEED WINDS IN EXOPLANET ATMOSPHERES THROUGH OBSERVATIONS OF ANOMALOUS DOPPLER SHIFTS DURING TRANSIT

    SciTech Connect (OSTI)

    Miller-Ricci Kempton, Eliza [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Rauscher, Emily, E-mail: ekempton@ucolick.org [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721 (United States)

    2012-06-01T23:59:59.000Z

    Three-dimensional (3D) dynamical models of hot Jupiter atmospheres predict very strong wind speeds. For tidally locked hot Jupiters, winds at high altitude in the planet's atmosphere advect heat from the day side to the cooler night side of the planet. Net wind speeds on the order of 1-10 km s{sup -1} directed towards the night side of the planet are predicted at mbar pressures, which is the approximate pressure level probed by transmission spectroscopy. These winds should result in an observed blueshift of spectral lines in transmission on the order of the wind speed. Indeed, Snellen et al. recently observed a 2 {+-} 1 km s{sup -1} blueshift of CO transmission features for HD 209458b, which has been interpreted as a detection of the day-to-night (substellar to anti-stellar) winds that have been predicted by 3D atmospheric dynamics modeling. Here, we present the results of a coupled 3D atmospheric dynamics and transmission spectrum model, which predicts the Doppler-shifted spectrum of a hot Jupiter during transit resulting from winds in the planet's atmosphere. We explore four different models for the hot Jupiter atmosphere using different prescriptions for atmospheric drag via interaction with planetary magnetic fields. We find that models with no magnetic drag produce net Doppler blueshifts in the transmission spectrum of {approx}2 km s{sup -1} and that lower Doppler shifts of {approx}1 km s{sup -1} are found for the higher drag cases, results consistent with-but not yet strongly constrained by-the Snellen et al. measurement. We additionally explore the possibility of recovering the average terminator wind speed as a function of altitude by measuring Doppler shifts of individual spectral lines and spatially resolving wind speeds across the leading and trailing terminators during ingress and egress.

  13. Different Virtual Stator Winding Configurations of Open-End Winding Five-Phase PM Machines for Wide Speed Range without Flux Weakening Operation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Different Virtual Stator Winding Configurations of Open-End Winding Five-Phase PM Machines for Wide of double-ended inverter system for wide-speed range of open- winding five phase PM machines. Different virtual winding configurations (star, pentagon, pentacle and bipolar) can be obtained by choosing

  14. High speed air pneumatic wind shield wiping design

    E-Print Network [OSTI]

    Heyward, Moses A

    2005-01-01T23:59:59.000Z

    In this creative design process a number of designs were constructed, implemented and tested in order to assess the feasibility of using high speed to create a curtain to repel the rain from the automobile windshield instead ...

  15. Adaptive pitch control for variable speed wind turbines

    DOE Patents [OSTI]

    Johnson, Kathryn E. (Boulder, CO); Fingersh, Lee Jay (Westminster, CO)

    2012-05-08T23:59:59.000Z

    An adaptive method for adjusting blade pitch angle, and controllers implementing such a method, for achieving higher power coefficients. Average power coefficients are determined for first and second periods of operation for the wind turbine. When the average power coefficient for the second time period is larger than for the first, a pitch increment, which may be generated based on the power coefficients, is added (or the sign is retained) to the nominal pitch angle value for the wind turbine. When the average power coefficient for the second time period is less than for the first, the pitch increment is subtracted (or the sign is changed). A control signal is generated based on the adapted pitch angle value and sent to blade pitch actuators that act to change the pitch angle of the wind turbine to the new or modified pitch angle setting, and this process is iteratively performed.

  16. Self-excited induction generator for variable-speed wind turbine generation

    SciTech Connect (OSTI)

    Muljadi, E.; Gregory, B. [National Renewable Energy Lab., Golden, CO (United States)] [National Renewable Energy Lab., Golden, CO (United States); Broad, D. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Electrical Engineering] [Colorado State Univ., Fort Collins, CO (United States). Dept. of Electrical Engineering

    1996-10-01T23:59:59.000Z

    When an induction generator is connected to a utility bus, the voltage and frequency at the terminal of the generator are the same as the voltage and frequency of the utility. The reactive power needed by the induction generator is supplied by the utility and the real power is returned to the utility. The rotor speed varies within a very limited range, and the reactive power requirement must be transported through a long line feeder, thus creating additional transmission losses. The energy captured by a wind turbine can be increased if the rotor speed can be adjusted to follow wind speed variations. For small applications such as battery charging or water pumping, a stand alone operation can be implemented without the need to maintain the output frequency output of the generator. A self- excited induction generator is a good candidate for a stand alone operation where the wind turbine is operated at variable speed. Thus the performance of the wind turbine can be unproved. In this paper, we examine a self-excited induction generator operated in a stand alone mode. A potential application for battery charging is given. The output power of the generator will be controlled to improve the performance of the wind turbine.

  17. MASON LAB B-7 WIND TUNNEL OPERATING INSTRUCTIONS Our wind tunnel is a low speed tunnel with a test section 15"x24" It has a digital controller

    E-Print Network [OSTI]

    Haller, Gary L.

    MASON LAB B-7 WIND TUNNEL OPERATING INSTRUCTIONS Our wind tunnel is a low speed tunnel with a test up to a maximum velocity of about 39M/s (~130 feet/s , 88mph) We have a 2 axis force balance that can measure lift (~25 N) and drag (~8 N) PRECAUTIONS: ALL OBJECTS MUST BE SECURED BEFORE STARTING WIND TUNNEL

  18. Solar wind suprathermal electron Stahl widths across high-speed stream structures

    SciTech Connect (OSTI)

    Skoug, Ruth M [Los Alamos National Laboratory; Steinberg, John T [Los Alamos National Laboratory; Goodrich, Katherine A [Los Alamos National Laboratory; Anderson, Brett R [DARTMUTH UNIV.

    2011-01-03T23:59:59.000Z

    Suprathermal electrons (100-1500 eV) observed in the solar wind typically show a strahl distribution, that is, a beam directed away from the Sun along the magnetic field direction. The strahl width observed at 1 AU is highly variable, ranging from 10-70 degrees. The obsenred finite width of the strahl results from the competition between beam focusing as the interplanetary magnetic field strength drops with distance from the Sun, and pitch-angle scattering as the beam interacts with the solar wind plasma in transit from the sun. Here we examine strahl width, observed with ACE SWEPAM across high-speed stream structures to investigate variations in electron scattering as a function of local plasma characteristics. We find that narrow strahls (less than 20 degrees wide), indicating reduced scattering, are observed within high-speed streams. Narrow strahls are also observed in both very low temperature solar wind, in association with ICMEs. Case studies of high-speed streams typically show the strahl narrowing at the leading edge of the stream. In some cases, the strahl narrows at the reverse shock or pressure wave, in other cases at the stream interface. The narrowing can either occur discontinuously or gradually over a period of hours. Within the high-speed wind, the strahl remains narrow for a period of hours to days, and then gradually broadens. The strahl width is roughly constant at all energies across these structures. For some fraction of high-speed streams, counterstreaming is associated with passage of the corotating interaction region. In these cases, we find the widths of the two counterstreaming beams frequently differ by more than 40 degrees. This dramatic difference in strahl width contrasts with observations in the solar wind as a whole, in which counterstreaming strahls typically differ in width by less than 20 degrees.

  19. Robust STATCOM Control for the Enhancement of Fault Ride-Through Capability of Fixed Speed Wind Generators

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    -slip relationships as well as through simulations. The wind generator is a highly nonlinear system, which is modelled power generation. This type of wind generator always consumes reactive power from the grid. WhenRobust STATCOM Control for the Enhancement of Fault Ride-Through Capability of Fixed Speed Wind

  20. SOLAR WIND HELIUM ABUNDANCE AS A FUNCTION OF SPEED AND HELIOGRAPHIC LATITUDE: VARIATION THROUGH A SOLAR CYCLE

    E-Print Network [OSTI]

    Richardson, John

    SOLAR WIND HELIUM ABUNDANCE AS A FUNCTION OF SPEED AND HELIOGRAPHIC LATITUDE: VARIATION THROUGH of the variation of the relative abundance of helium to hydrogen in the solar wind as a function of solar wind theoretical work in which enhancements of coronal helium lead to stagnation of the escaping proton flux

  1. Experimental investigation of aerodynamic devices for wind turbine rotational speed control. Phase 1

    SciTech Connect (OSTI)

    Miller, L.S. [Wichita State Univ., KS (United States)

    1995-02-01T23:59:59.000Z

    An investigation was undertaken to identify the aerodynamic performance of five separate trailing-edge control devices, and to evaluate their potential for wind turbine overspeed and power modulation applications. A modular two-dimensional wind tunnel model was constructed and evaluated during extensive wind tunnel testing. Aerodynamic lift, drag, suction, and pressure coefficient data were acquired and analyzed for various control configurations and angles of attack. To further interpret their potential performance, the controls were evaluated numerically using a generic wind turbine geometry and a performance analysis computer program. Results indicated that the Spoiler-Flap control configuration was best softed for turbine braking applications. It exhibited a large negative suction coefficient over a broad angle-of-attack range, and good turbine braking capabilities, especially at low tip-speed ratio.

  2. High resolution reanalysis of wind speeds over the British Isles for wind energy integration 

    E-Print Network [OSTI]

    Hawkins, Samuel Lennon

    2012-11-29T23:59:59.000Z

    The UK has highly ambitious targets for wind development, particularly offshore, where over 30GW of capacity is proposed for development. Integrating such a large amount of variable generation presents enormous challenges. ...

  3. PHYSICAL REVIEW E 88, 042146 (2013) Uncovering wind turbine properties through two-dimensional stochastic modeling of wind dynamics

    E-Print Network [OSTI]

    Peinke, Joachim

    PHYSICAL REVIEW E 88, 042146 (2013) Uncovering wind turbine properties through two, such as the rated speed of the wind turbine or the descriptive wind speed statistics, can be related to the equations describing the evolution of power production and wind speed at single wind turbines. DOI: 10

  4. ON THE ORIGIN OF THE SLOW SPEED SOLAR WIND: HELIUM ABUNDANCE VARIATIONS

    SciTech Connect (OSTI)

    Rakowski, Cara E.; Laming, J. Martin [Space Science Division, Naval Research Laboratory Code 7674L, Washington, DC 20375 (United States)

    2012-07-20T23:59:59.000Z

    The first ionization potential (FIP) effect is the by now well-known enhancement in abundance over photospheric values of Fe and other elements with FIP below about 10 eV observed in the solar corona and slow speed solar wind. In our model, this fractionation is achieved by means of the ponderomotive force, arising as Alfven waves propagate through or reflect from steep density gradients in the solar chromosphere. This is also the region where low FIP elements are ionized, and high FIP elements are largely neutral leading to the fractionation as ions interact with the waves but neutrals do not. Helium, the element with the highest FIP and consequently the last to remain neutral as one moves upward, can be depleted in such models. Here, we investigate this depletion for varying loop lengths and magnetic field strengths. Variations in this depletion arise as the concentration of the ponderomotive force at the top of the chromosphere varies in response to Alfven wave frequency with respect to the resonant frequency of the overlying coronal loop, the magnetic field, and possibly also the loop length. We find that stronger depletions of He are obtained for weaker magnetic field, at frequencies close to or just above the loop resonance. These results may have relevance to observed variations of the slow wind solar He abundance with wind speed, with slower slow speed solar wind having a stronger depletion of He.

  5. On the relationship between temperature and wind speed in the atmospheric surface layer

    E-Print Network [OSTI]

    Pierrard, John Martin

    1958-01-01T23:59:59.000Z

    LIBRAR& A AN m os??E " "" ON THE RELATIONSHIP BETWEEN T" MP. "RATURE AND WIND SPEED IN THE ATMOSPHERIC SURFACE LAYER A Thesis John Me Pierrard Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial... fulfillment of the requirements for the degree of MASTER OF SCI"NCE August 1958 Ma)or Sub)ect: Meteorology ON THE RELATIONSHIP BETWEEN TEMPERATURE AND WIND SP ED IN THE ATMOSPHERIC SUBRACE LAYER A Thesis John M. Pierrard Approved as to style...

  6. A study of wind-speed maxima near the surface over the south central United States 

    E-Print Network [OSTI]

    Beckman, Samuel Karl

    1973-01-01T23:59:59.000Z

    , the front is indicated by a wind shift, pressure change, or a decrease in moisture. In some cases the position of the cold front may be confused with the position of a dew-point front (Henry and Thompson, 1963) which is active in west Texas, eastern New... N. A wind speed of at least 30 kt was considered to be strong. The initial flow is confined on both the east and west sides. The mountains restrict the western extent of the southerly flow. The eastward extent of the southerly flow is determined...

  7. Solar Wind Sources in the Late Declining Phase of Cycle 23: Effects of the Weak Solar Polar Field on High Speed Streams

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    Isenberg, P.A. (eds. ) Solar Wind Nine, AIP Conf. Proc. 471,AT SOLAR MINIMUM Solar Wind Sources in the Late Decliningfor their high speed solar wind streams that dominate the

  8. Prediction of wind speed profiles for short-term forecasting in the offshore environment R.J. Barthelmie and G. Giebel

    E-Print Network [OSTI]

    in planning of maintenance visits to offshore wind farms. In most cases the basis for the predictionPrediction of wind speed profiles for short-term forecasting in the offshore environment R wind farms. The main effects considered here are: wind speed gradients in the coastal zone, vertical

  9. Systematic approach for PID controller design for pitch-regulated, variable-speed wind turbines

    SciTech Connect (OSTI)

    Hand, M.M. [National Renewable Energy Lab., Golden, CO (United States); Balas, M.J. [Univ. of Colorado, Boulder, CO (United States). Dept. of Aerospace Engineering Sciences

    1997-11-01T23:59:59.000Z

    Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three regions of operation. This paper focuses on controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative (PID) controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship of the two opposing metrics is easily visualized. 2 refs., 9 figs.

  10. Evidence of a Threshold Wind Speed in Tower-mounted Scatterometer Data David W. Draper and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    . Evidence of the threshold wind speed and a hysteresis effect have been observed in airship and wave tank in airship data [2]. YSCAT, an ultra-wideband (2-14 GHz) tower-mounted scat- terometer, provides significant

  11. Operational behavior of a double-fed permanent magnet generator for wind turbines

    E-Print Network [OSTI]

    Reddy, Sivananda Kumjula

    2005-01-01T23:59:59.000Z

    Greater efficiency in wind turbine systems is achieved by allowing the rotor to change its rate of rotation as the wind speed changes. The wind turbine system is decoupled from the utility grid and a variable speed operation ...

  12. United States Wind Resource Map: Annual Average Wind Speed at 80 Meters

    Wind Powering America (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:Deployment Activities Printable80 m 01-APR-2011 2.1.1 Wind

  13. Rotor Speed Dependent Yaw Control of Wind Turbines Based on Empirical Data

    SciTech Connect (OSTI)

    Kragh, K. A.; Fleming, P. A.

    2012-01-01T23:59:59.000Z

    When extracting energy from the wind using horizontal-axis upwind wind turbines, a primary condition for maximum power yield is the ability to align the rotor axis with the dominating wind direction. Attempts have been made to improve yaw alignment by applying advanced measurement techniques such as LIDARs. This study is focused at assessing the current performance of an operating turbine and exploring how the yaw alignment can be improved using existing measurements. By analyzing available turbine and met mast data a correction scheme for the original yaw alignment system is synthesized. The correction scheme is applied and it is seen that with the correction scheme in place, the power yield below rated is raised 1-5 percent. Furthermore, results indicate that blade load variations are decreased when the correction scheme is applied. The results are associated with uncertainties due to the amount of available data and the wind site climate. Further work should be focused at gathering more experimental data.

  14. Observational evidence from two mountainous regions that near surface wind speeds are declining more rapidly at higher elevations

    E-Print Network [OSTI]

    Zimmermann, Niklaus E.

    for wind energy generation [e.g., Burton et al., 2001], evapotranspiration [e.g., McVicar and Jupp, 1999 wind speeds are declining more rapidly at higher elevations than lower elevations: 1960­2006 Tim R. Mc and Dirk R. Schmatz5 Received 20 December 2009; revised 26 January 2010; accepted 2 February 2010

  15. Wind Resource Assessment in Europe Using Emergy

    E-Print Network [OSTI]

    Paudel, Subodh; Santarelli, Massimo; Martin, Viktoria; Lacarriere, Bruno; Le Corre, Olivier

    2014-01-01T23:59:59.000Z

    mance characteristics of wind generator. The wind speed atcharacteristics of the wind generator. When wind speed is

  16. Wind accretion in binary stars II. Accretion rates

    E-Print Network [OSTI]

    Tom Theuns; Henri Boffin; Alain Jorissen

    1996-02-18T23:59:59.000Z

    Smoothed particle hydrodynamics (SPH) is used to estimate accretion rates of mass, linear and angular momentum in a binary system where one component undergoes mass loss through a wind. Physical parameters are chosen such as to model the alleged binary precursors of barium stars, whose chemical peculiarities are believed to result from the accretion of the wind from a companion formerly on the asymptotic giant branch (AGB). The binary system modelled consists of a 3 solar masses AGB star on the main sequence, in a 3AU circular orbit. Three-dimensional simulations are performed for gases with polytropic indices gamma=1, 1.1 and 1.5, to bracket more realistic situations that would include radiative cooling. Mass accretion rates are found to depend on resolution and we estimate typical values of 1-2% for the gamma=1.5 case and 8% for the other models. The highest resolution obtained (with 400k particles) corresponds to an accretor of linear size 16 solar radii. Despite being (in the gamma = 1.5 case) about ten times smaller than theoretical estimates based on the Bondi-Hoyle prescription, the SPH accretion rates remain large enough to explain the pollution of barium stars. Uncertainties in the current SPH rates remain however, due to the simplified treatment of the wind acceleration mechanism, as well as to the absence of any cooling prescription and to the limited numerical resolution. Angular momentum transfer leads to significant spin up of the accretor and can account for the rapid rotation of HD165141, a barium star with a young white dwarf companion and a rotation rate unusually large among K giants.

  17. A study of wind-speed maxima near the surface over the south central United States

    E-Print Network [OSTI]

    Beckman, Samuel Karl

    1973-01-01T23:59:59.000Z

    GMT, 28 April 1967, showing isotachs and fronts. . . . . . 26 12. Synoptic map for 1200 GMT, 28 April 1967. . 28 13. Time cross section for Abilene, Texas, April 1967. . . . 11 14. Change in the wind-speed profile ot Oklahoma City, Oklahoma..., but the summer months had more days with low-level jets. They further stated that the jets occurred in all seasons and should be related to the synoptic conditions. Crawford and Hudson (1970), using observations from a 1500-ft television tower at Oklahoma...

  18. Error propagation equations for estimating the uncertainty in high-speed wind tunnel test results

    SciTech Connect (OSTI)

    Clark, E.L.

    1994-07-01T23:59:59.000Z

    Error propagation equations, based on the Taylor series model, are derived for the nondimensional ratios and coefficients most often encountered in high-speed wind tunnel testing. These include pressure ratio and coefficient, static force and moment coefficients, dynamic stability coefficients, and calibration Mach number. The error equations contain partial derivatives, denoted as sensitivity coefficients, which define the influence of free-steam Mach number, M{infinity}, on various aerodynamic ratios. To facilitate use of the error equations, sensitivity coefficients are derived and evaluated for five fundamental aerodynamic ratios which relate free-steam test conditions to a reference condition.

  19. Fig. 1. One hour measured irradiance and wind speed data with 0.2 seconds, 3 seconds and 1 minute (interpolated) sampling time.

    E-Print Network [OSTI]

    Sera, Dezso

    Fig. 1. One hour measured irradiance and wind speed data with 0.2 seconds, 3 seconds and 1 minute to intermittent character of the solar irradiance and wind. The actual power quality standards provide only of the solar irradiance and wind speed in fast changing conditions on the utility grid. This work proposes

  20. Effect of Tip-Speed Constraints on the Optimized Design of a Wind Turbine

    SciTech Connect (OSTI)

    Dykes, K.; Resor, B.; Platt, A.; Guo, Y.; Ning, A.; King, R.; Parsons, T.; Petch, D.; Veers, P.

    2014-10-01T23:59:59.000Z

    This study investigates the effect of tip-velocity constraints on system levelized cost of energy (LCOE). The results indicate that a change in maximum tip speed from 80 to 100~m/s could produce a 32% decrease in gearbox weight (a 33% reduction in cost) which would result in an overall reduction of 1%-9% in system LCOE depending on the design approach. Three 100~m/s design cases were considered including a low tip-speed ratio/high-solidity rotor design, a high tip-speed ratio/ low-solidity rotor design, and finally a flexible blade design in which a high tip-speed ratio was used along with removing the tip deflection constraint on the rotor design. In all three cases, the significant reduction in gearbox weight caused by the higher tip-speed and lower overall gear ratio was counterbalanced by increased weights for the rotor and/or other drivetrain components and the tower. As a result, the increased costs of either the rotor or drivetrain components offset the overall reduction in turbine costs from down-sizing the gearbox. Other system costs were not significantly affected, whereas energy production was slightly reduced in the 100~m/s case low tip-speed ratio case and increased in the high tip-speed ratio case. This resulted in system cost of energy reductions moving from the 80~m/s design to the 100~m/s designs of 1.2% for the low tip-speed ratio, 4.6% for the high tip-speed ratio, and 9.5% for the final flexible case (the latter result is optimistic because the impact of deflection of the flexible blade on power production was not modeled). Overall, the results demonstrate that there is a trade-off in system design between the maximum tip velocity and the overall wind plant cost of energy, and there are many trade-offs within the overall system in designing a turbine for a high maximum tip velocity.

  1. IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 23, NO. 2, JUNE 2008 551 Sliding Mode Power Control of Variable-Speed Wind

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in variable-speed wind energy conversion sys- tems (VS-WECS). These systems have two operation regions de of Variable-Speed Wind Energy Conversion Systems Brice Beltran, Tarek Ahmed-Ali, and Mohamed El Hachemi (newton meter). Tg Generator torque in the rotor side (newton meter). Ths High-speed torque (newton meter

  2. A WRF Ensemble for Improved Wind Speed Forecasts at Turbine Height ADAM J. DEPPE AND WILLIAM A. GALLUS JR.

    E-Print Network [OSTI]

    McCalley, James D.

    . 1. Introduction In recent years, wind energy production has under- gone rapid growth, and the U over both space and time. Therefore, the production rates of wind energy fluctuate more strongly than percentage of total power per capita coming from wind energy in 2010 (Department of Energy 2010). Even fewer

  3. Mining Markov chain transition matrix from wind speed time series data Zhe Song a,

    E-Print Network [OSTI]

    Kusiak, Andrew

    to wind energy industry in terms of wind turbine optimal control, wind energy dispatch/scheduling, wind in recent years and even more aggressive wind energy installations are envisioned in various economy & Bolinger, 2006). Rapid development of wind energy provides rich environments for wind energy related

  4. Speed Training: Improving the Rate of Backpropagation Learning through Stochastic Sample Presentation

    E-Print Network [OSTI]

    Martinez, Tony R.

    Speed Training: Improving the Rate of Backpropagation Learning through Stochastic Sample. However, using complex neural networks to learn very large training sets is often problematic, imposing prohibitive time constraints on the training process. We present four practical methods for dramatically

  5. Robust control for wind power systems A. Pintea 1,2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    design applied to a horizontal wind turbine, functioning in the above rated wind speeds area. The turbines chosen for study in this paper are variable speed wind turbines and the main focus will fall. The controller presented here, is a robust digital controller which aims to regulate the wind turbine rotor speed

  6. Development and Validation of WECC Variable Speed Wind Turbine Dynamic Models for Grid Integration Studies

    SciTech Connect (OSTI)

    Behnke, M.; Ellis, A.; Kazachkov, Y.; McCoy, T.; Muljadi, E.; Price, W.; Sanchez-Gasca, J.

    2007-09-01T23:59:59.000Z

    This paper describes reduced-order, simplified wind turbine models for analyzing the stability impact of large arrays of wind turbines with a single point of network interconnection.

  7. Spectrum of wind speed fluctuations encountered by a rotating blade of a wind energy conversion system: observations and theory

    SciTech Connect (OSTI)

    Connell, J.R.

    1981-11-01T23:59:59.000Z

    This report proves that the characteristics of turbulence that are experienced by a rotating wind turbine rotor blade are in principle and in practice very different than those experienced by a nonrotating rotor blade. Thus conventional wind characteristics, which are formulated for the nonrotating frame of reference, are more inaccurate than generally supposed. The measurements and mathematical model that are presented for turbulence observed in the rotating frame of reference represent the third phase of the Pacific Northwest Laboratory work aimed at providing an accurate turbulence description for use in the design and evaluation of the performance of wind turbines. The first phase of work was the measurement of wind with a vertical plane array of anemometers. The second phase was the physical interpretation of the measurements in terms of implications for wind turbine rotors and initiation of development of a model of wind/wind turbine interaction. The third phase involved measurement of turbulence by rotating sensors and mathematical development of a physical model of this representation of turbulence as independent checks and expansions of the vertical plane array results. A fourth phase, to correlate real wind turbine response with rotationally measured turbulence and thereby understand the wind/wind turbine interaction, is in progress and preliminary results are quite promising.

  8. WIND DATA REPORT Mattapoisett

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Mattapoisett Mattapoisett, Massachusetts December 1, 2006 ­ February 28, 2007...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  9. Forecasting of wind speed using wavelets analysis and cascade-correlation neural networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    such as sunlight, wind, rain or geothermal heat. Wind energy is actually one of the fastest-growing forms, that is why its wind energy market has been progressing steadily in recent years. While in 2000, there were only 30 MW of wind generating capacity in France, the total installed capacity at the end of 2007

  10. The Impacts of Wind Speed Trends and Long-term Variability in Relation to Hydroelectric

    E-Print Network [OSTI]

    Kohfeld, Karen

    and Long-term Variability in Relation to Hydroelectric Reservoir Inflows on Wind Power in the Pacific through diversification. In hydroelectric dominated systems, like the PNW, the benefits of wind power can diversification can be maximized. Keywords: Wind power; Hydroelectricity; Renewable energy; Climate variability

  11. A Robust STATCOM Control to Augment LVRT capability of Fixed Speed Wind Turbines

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    equipped with induction generators. The wind generator is a highly nonlinear system, and in this paper% of the nominal voltage for up to 140 ms [3]. Induction generators are preferred as wind generators for their low and the behavior of STATCOM dur- ing balanced or unbalanced grid faults (fault ride through), allow wind generators

  12. Remote sensing of total integrated water vapor, wind speed, and cloud liquid water over the ocean using the Special Sensor Microwave/Imager (SSM/I)

    E-Print Network [OSTI]

    Manning, Norman Willis William

    1997-01-01T23:59:59.000Z

    A modified D-matrix retrieval method is the basis of the refined total integrated water vapor (TIWV), total integrated cloud liquid water (CLW), and surface wind speed (WS) retrieval methods that are developed. The 85 GHZ polarization difference...

  13. Effect of wind speed on the growth of the upper convective zone in a solar pond

    E-Print Network [OSTI]

    McMinn, Steven Lee

    1990-01-01T23:59:59.000Z

    [2]. The distance which the wind has to act on the surface of a pond is commonly called fetch, or fetch length. The purpose of the nets or other devices used in wind suppression is to reduce the fetch and transmit some of the energy in the waves... to the sides of the pond. Wind mixing of the upper convective zone can be thought of as converting some of the kinetic energy in the wind to potential energy in the fluid by a process called entrainment. Entrainment is defined in detail in Chapter V...

  14. Effect of wind speed on the growth of the upper convective zone in a solar pond 

    E-Print Network [OSTI]

    McMinn, Steven Lee

    1990-01-01T23:59:59.000Z

    [2]. The distance which the wind has to act on the surface of a pond is commonly called fetch, or fetch length. The purpose of the nets or other devices used in wind suppression is to reduce the fetch and transmit some of the energy in the waves... to the sides of the pond. Wind mixing of the upper convective zone can be thought of as converting some of the kinetic energy in the wind to potential energy in the fluid by a process called entrainment. Entrainment is defined in detail in Chapter V...

  15. High-Speed Optical Spectroscopy of a Cataclysmic Variable Wind BZ Camelopardalis

    E-Print Network [OSTI]

    Ringwald, F A

    1997-01-01T23:59:59.000Z

    BZ Cam is the first cataclysmic variable star with an accretion disk wind evident in its optical spectrum. The wind was found by Thorstensen, who discovered intermittent P Cygni profiles occurring simultaneously in He I 5876 Angstroms and H alpha. We have since obtained spectra with 0.4-Angstroms/pixel dispersion and 60-s time resolution. We find a wind much faster and more rapidly variable than the radiatively accelerated winds of OB stars, Wolf-Rayet stars, or luminous blue variables. Instead of showing blob ejection, the whole wind of BZ Cam appears to turn on and off. We use this to measure the acceleration law of a CV wind for the first time. The velocity increases linearly with time, attaining blue edge velocities near -3000 km/s, and absorption velocities near -1700 km/s, in 6 to 8 min after starting near rest. We also find a subsequent linear deceleration to nearly rest in 30 to 40 min, perhaps an effect of dilution as the wind expands. No periodicity from rotational outflow is obvious. This wind is e...

  16. Soil erosion rates caused by wind and saltating sand stresses in a wind tunnel

    SciTech Connect (OSTI)

    Ligotke, M.W.

    1993-02-01T23:59:59.000Z

    Wind erosion tests were performed in a wind tunnel in support of the development of long-term protective barriers to cap stabilized waste sites at the Hanford Site. Controlled wind and saltating sand erosive stresses were applied to physical models of barrier surface layers to simulate worst-case eolian erosive stresses. The goal of these tests was to provide information useful to the design and evaluation of the surface layer composition of an arid-region waste site barrier concept that incorporates a deep fine-soil reservoir. A surface layer composition is needed that will form an armor resistant to eolian erosion during periods of extreme dry climatic conditions, especially when such conditions result in the elimination or reduction of vegetation by water deprivation or wildfire. Because of the life span required of Hanford waste barriers, it is important that additional work follow these wind tunnel studies. A modeling effort is planned to aid the interpretation of test results with respect to the suitability of pea gravel to protect the finite-soil reservoir during long periods of climatic stress. It is additionally recommended that wind tunnel tests be continued and field data be obtained at prototype or actual barrier sites. Results wig contribute to barrier design efforts and provide confidence in the design of long-term waste site caps for and regions.

  17. High-Speed Optical Spectroscopy of a Cataclysmic Variable Wind: BZ Camelopardalis

    E-Print Network [OSTI]

    F. A. Ringwald; T. Naylor

    1997-10-02T23:59:59.000Z

    BZ Cam is the first cataclysmic variable star with an accretion disk wind evident in its optical spectrum. The wind was found by Thorstensen, who discovered intermittent P Cygni profiles occurring simultaneously in He I 5876 Angstroms and H alpha. We have since obtained spectra with 0.4-Angstroms/pixel dispersion and 60-s time resolution. We find a wind much faster and more rapidly variable than the radiatively accelerated winds of OB stars, Wolf-Rayet stars, or luminous blue variables. Instead of showing blob ejection, the whole wind of BZ Cam appears to turn on and off. We use this to measure the acceleration law of a CV wind for the first time. The velocity increases linearly with time, attaining blue edge velocities near -3000 km/s, and absorption velocities near -1700 km/s, in 6 to 8 min after starting near rest. We also find a subsequent linear deceleration to nearly rest in 30 to 40 min, perhaps an effect of dilution as the wind expands. No periodicity from rotational outflow is obvious. This wind is erratic and incessantly variable, and perhaps bipolar and face-on, but not highly collimated. The P Cygni absorption events trace out sawtooth waves, occurring within 30 to 40 white dwarf radii from the disk. This is the approximate size of the disk, as well as the disk/wind transition region recently postulated by Knigge and Drew. We estimate a distance of 830 +/- 160 pc, and an orbital inclination i such that 12 < i(degrees) < 40.

  18. WIND DATA REPORT Presque Isle

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Presque Isle June 1, 2005 ­ August 31, 2005 Prepared for United States Department...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  19. WIND DATA REPORT Presque Isle

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Presque Isle December 1, 2004 ­ February 28, 2005 Prepared for United States.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  20. WIND DATA REPORT Presque Isle

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Presque Isle December 1, 2004 ­ December 1, 2005 Prepared for United States ......................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  1. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island June 1, 2003 ­ August 31, 2003 Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distribution

  2. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island December 1, 2003 ­ February 29, 2004 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distribution

  3. WIND DATA REPORT Presque Isle

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Presque Isle March 1, 2005 ­ May 31, 2005 Prepared for United States Department.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  4. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island March 1, 2003 ­ May 31, 2003 Prepared for Massachusetts Technology...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  5. WIND DATA REPORT FALMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT FALMOUTH, MA June1, 2004 to August 31, 2004. Prepared for Massachusetts Technology...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 8 Wind Speed Distributions

  6. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island September 1, 2003 ­ November 30, 2003 Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distribution

  7. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island March 1, 2004 ­ May 31, 2004 Prepared for Massachusetts Technology...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distribution

  8. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island June 1, 2004 ­ August 31, 2004 Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distribution

  9. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island December 1, 2004 ­ February 28, 2005 Prepared for Massachusetts.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distribution

  10. WIND DATA REPORT DARTMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT DARTMOUTH, MA March 26th 2005 to May 31st 2005. Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  11. WIND DATA REPORT FALMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT FALMOUTH, MA June 1st 2004- May 31st 2005 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Distributions......................................................................................................... 11 Monthly Average Wind Speeds

  12. WIND DATA REPORT Kingston, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Kingston, MA March 1, 2006 - May 31, 2006 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions.......

  13. WIND DATA REPORT Nantucket, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Nantucket, MA September 1st 2005 to November 30th 2005. Prepared for Massachusetts.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  14. WIND DATA REPORT Wellfleet, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Wellfleet, MA December 1st , 2006 ­ February 28th , 2007 Prepared...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  15. WIND DATA REPORT Nantucket, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Nantucket, MA June 1st 2006 to August 31th 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed D

  16. WIND DATA REPORT Truro, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Truro, Massachusetts March 24th to May 31st , 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  17. WIND DATA REPORT Chester, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Chester, MA December 2006 ­ February 2007 Prepared for Massachusetts Technology...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  18. WIND DATA REPORT Brewster, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Brewster, Massachusetts December 1, 2005 - February 28, 2006 Prepared.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 12 Wind Speed Di

  19. WIND DATA REPORT Truro, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Truro, Massachusetts December, 2006 1st to February 28th , 2007 Prepared...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  20. WIND DATA REPORT Brewster, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Brewster, Massachusetts June 1, 2006 - August 31, 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Di

  1. WIND DATA REPORT Chester, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Chester, MA March 2007 ­ May 2007 Prepared for Massachusetts Technology...................................................................................................................... 8 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  2. WIND DATA REPORT Chester, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Chester, MA September ­ November 2006 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  3. WIND DATA REPORT DARTMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT DARTMOUTH, MA September 1st 2005 to November 30th 2005. Prepared for Massachusetts.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  4. WIND DATA REPORT Kingston, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Kingston, MA December 1, 2005 - February 28, 2006 Prepared for Massachusetts.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distribution

  5. WIND DATA REPORT Brewster, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Brewster, Massachusetts September 1, 2006 - November 30, 2006 Prepared.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions..................

  6. WIND DATA REPORT Nantucket, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Nantucket, MA December 1st 2005 to February 28th 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  7. WIND DATA REPORT Gardner NCCI

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Gardner NCCI March 1, 2007 ­ May 31, 2007 Prepared for Massachusetts Technology...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  8. WIND DATA REPORT FALMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT FALMOUTH, MA Sep 1st 2004 to Nov 30th 2004. Prepared for Massachusetts Technology...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  9. WIND DATA REPORT Chester, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Chester, MA June ­ August 2006 Prepared for Massachusetts Technology Collaborative.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  10. WIND DATA REPORT September 2005

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Lynn, MA September 2005 Prepared for Massachusetts Technology Collaborative 75.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Monthly Average Wind Speeds

  11. WIND DATA REPORT Nantucket, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Nantucket, MA June 1st 2005 to August 31st 2005. Prepared for Massachusetts.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  12. WIND DATA REPORT Truro, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Truro, Massachusetts September 1st to November 30th , 2006 Prepared.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  13. WIND DATA REPORT Truro, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Truro, Massachusetts June 1st to August 31st , 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  14. WIND DATA REPORT DARTMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT DARTMOUTH, MA June 1st 2005 to August 31st 2005. Prepared for Massachusetts.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  15. WIND DATA REPORT Brewster, Massachusetts

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Brewster, Massachusetts March 1, 2006 - May 31, 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributi

  16. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island September 1, 2004 ­ November 30, 2004 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distribution.............

  17. WIND DATA REPORT DARTMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT DARTMOUTH, MA December 1st 2005 to February 28th 2006. Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  18. WIND DATA REPORT Dartmouth, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Dartmouth, MA March 1st 2006 to May 31th 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  19. WIND DATA REPORT Wellfleet, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Wellfleet, MA March 1st , 2007 ­ May 31st , 2007 Prepared for Massachusetts...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  20. WIND DATA REPORT Gardner NCCI

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Gardner NCCI September 1, 2007 ­ November 30, 2007 Prepared for Massachusetts...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  1. WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Thompson Island March 1, 2005 ­ May 31, 2005 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distribution

  2. WIND DATA REPORT Chester, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Chester, MA April 14 ­ May 31, 2006 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  3. WIND DATA REPORT FALMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT FALMOUTH, MA Dec 1st 2004 to Feb 28th 2005. Prepared for Massachusetts Technology ...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  4. WIND DATA REPORT FALMOUTH, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT FALMOUTH, MA March 1st 2005 to May 31st 2005. Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  5. WIND DATA REPORT Dartmouth, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Dartmouth, MA June 1st 2006 to July 31th 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  6. WIND DATA REPORT Gardner NCCI

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Gardner NCCI June 1, 2007 ­ August 31, 2007 Prepared for Massachusetts Technology...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  7. WIND DATA REPORT Nantucket, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Nantucket, MA March 1st 2006 to May 31th 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distribut

  8. Uncovering wind turbine properties through two-dimensional stochastic modeling of wind dynamics

    E-Print Network [OSTI]

    Raischel, Frank; Lopes, Vitor V; Lind, Pedro G

    2012-01-01T23:59:59.000Z

    Using a method for stochastic data analysis, borrowed from statistical physics, we analyze synthetic data from a Markov chain model that reproduces measurements of wind speed and power production in a wind park in Portugal. From the theoretical point of view we argue that our methods can be used to extract unknown functional relations between two variables. We first show that indeed our analysis retrieves the power performance curve, which yields the relationship between wind speed and power production and discuss how such procedure can be extended for extracting functional relationships between pairs of physical variables in general. Second, we show how specific features, such as the turbine rated wind speed or the descriptive wind speed statistics, can be related with the equations describing the evolution of power production and wind speed at single wind turbines.

  9. Cambridge Danehy Park Wind Turbine Preliminary Project Assessment

    E-Print Network [OSTI]

    Cambridge Danehy Park Wind Turbine Preliminary Project Assessment Overview MIT Wind Energy Projects 4 / 25 2.5 / 25 Rated Wind Speed (m/s) 13 10 14.5 ~15 12 The above turbines were chosen to provide, several recent studies examining birds and wind turbines have observed that most birds usually avoid

  10. Variable-speed wind power system with improved energy capture via multilevel conversion

    DOE Patents [OSTI]

    Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

    2005-05-31T23:59:59.000Z

    A system and method for efficiently capturing electrical energy from a variable-speed generator are disclosed. The system includes a matrix converter using full-bridge, multilevel switch cells, in which semiconductor devices are clamped to a known constant DC voltage of a capacitor. The multilevel matrix converter is capable of generating multilevel voltage wave waveform of arbitrary magnitude and frequencies. The matrix converter can be controlled by using space vector modulation.

  11. Error propagation equations and tables for estimating the uncertainty in high-speed wind tunnel test results

    SciTech Connect (OSTI)

    Clark, E.L.

    1993-08-01T23:59:59.000Z

    Error propagation equations, based on the Taylor series model, are derived for the nondimensional ratios and coefficients most often encountered in high-speed wind tunnel testing. These include pressure ratio and coefficient, static force and moment coefficients, dynamic stability coefficients, calibration Mach number and Reynolds number. The error equations contain partial derivatives, denoted as sensitivity coefficients, which define the influence of free-stream Mach number, M{infinity}, on various aerodynamic ratios. To facilitate use of the error equations, sensitivity coefficients are derived and evaluated for nine fundamental aerodynamic ratios, most of which relate free-stream test conditions (pressure, temperature, density or velocity) to a reference condition. Tables of the ratios, R, absolute sensitivity coefficients, {partial_derivative}R/{partial_derivative}M{infinity}, and relative sensitivity coefficients, (M{infinity}/R) ({partial_derivative}R/{partial_derivative}M{infinity}), are provided as functions of M{infinity}.

  12. Structure of Turbulence in Katabatic Flows below and above the Wind-Speed Maximum

    E-Print Network [OSTI]

    Grachev, Andrey A; Di Sabatino, Silvana; Fernando, Harindra J S; Pardyjak, Eric R; Fairall, Christopher W

    2015-01-01T23:59:59.000Z

    Measurements of small-scale turbulence made over the complex-terrain atmospheric boundary layer during the MATERHORN Program are used to describe the structure of turbulence in katabatic flows. Turbulent and mean meteorological data were continuously measured at multiple levels at four towers deployed along the East lower slope (2-4 deg) of Granite Mountain. The multi-level observations made during a 30-day long MATERHORN-Fall field campaign in September-October 2012 allowed studying of temporal and spatial structure of katabatic flows in detail, and herein we report turbulence and their variations in katabatic winds. Observed vertical profiles show steep gradients near the surface, but in the layer above the slope jet the vertical variability is smaller. It is found that the vertical (normal to the slope) momentum flux and horizontal (along the slope) heat flux in a slope-following coordinate system change their sign below and above the wind maximum of a katabatic flow. The vertical momentum flux is directed...

  13. active stall wind: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    SeaWinds, and the Advanced Microwave Scanning Radiometer (AMSR). Scalar wind speed observed by AMSR was evaluated by using wind speed observed by SeaWinds. The...

  14. Effects of engine speed, fueling rate, and combustion phasing on the thermal stratification required to limit HCCI knocking intensity.

    SciTech Connect (OSTI)

    SjÞoberg, Magnus; Dec, John E.

    2004-12-01T23:59:59.000Z

    Thermal stratification has the potential to reduce pressure-rise rates and allow increased power output for HCCI engines. This paper systematically examines how the amount of thermal stratification of the core of the charge has to be adjusted to avoid excessive knock as the engine speed and fueling rate are increased. This is accomplished by a combination of multi-zone chemical-kinetics modeling and engine experiments, using iso-octane as the fuel. The experiments show that, for a low-residual engine configuration, the pressure traces are self-similar during changes to the engine speed when CA50 is maintained by adjusting the intake temperature. Consequently, the absolute pressure-rise rate measured as bar/ms increases proportionally with the engine speed. As a result, the knocking (ringing) intensity increases drastically with engine speed, unless counteracted by some means. This paper describes how adjustments of the thermal width of the in-cylinder charge can be used to limit the ringing intensity to 5 MW/m2 as both engine speed and fueling are increased. If the thermal width can be tailored without constraints, this enables smooth operation even for combinations of high speed, high load, and combustion phasing close to TDC. Since large alterations of the thermal width of the charge are not always possible, combustion retard is considered to reduce the requirement on the thermal stratification. The results show that combustion retard carries significant potential since it amplifies the benefit of a fixed thermal width. Therefore, the thermal stratification required for operation with an acceptable knocking intensity can be decreased substantially by the use of combustion retard. This enables combinations of high engine speed and high fueling rate even for operation with the naturally occurring thermal stratification. However, very precise control of the combustion phasing will likely be required for such operation.

  15. ENHANCED DISSIPATION RATE OF MAGNETIC FIELD IN STRIPED PULSAR WINDS BY THE EFFECT OF TURBULENCE

    SciTech Connect (OSTI)

    Takamoto, Makoto [Department of Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan); Inoue, Tsuyoshi [Department of Physics and Mathematics, Aoyama Gakuin University, Fuchinobe, Chuou-ku, Sagamihara 252-5258 (Japan); Inutsuka, Shu-ichiro, E-mail: takamoto@tap.scphys.kyoto-u.ac.jp, E-mail: inouety@phys.aoyama.ac.jp, E-mail: inutsuka@nagoya-u.jp [Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)

    2012-08-10T23:59:59.000Z

    In this paper, we report on turbulent acceleration of the dissipation of the magnetic field in the post-shock region of a Poynting flux-dominated flow, such as the Crab pulsar wind nebula. We have performed two-dimensional resistive relativistic magnetohydrodynamics simulations of subsonic turbulence driven by the Richtmyer-Meshkov instability at the shock fronts of the Poynting flux-dominated flows in pulsar winds. We find that turbulence stretches current sheets which substantially enhances the dissipation of the magnetic field, and that most of the initial magnetic field energy is dissipated within a few eddy-turnover times. We also develop a simple analytical model for turbulent dissipation of the magnetic field that agrees well with our simulations. The analytical model indicates that the dissipation rate does not depend on resistivity even in the small resistivity limit. Our findings can possibly alleviate the {sigma}-problem in the Crab pulsar wind nebulae.

  16. ANNUAL WIND DATA REPORT Thompson Island

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    ANNUAL WIND DATA REPORT Thompson Island March 1, 2002 ­ February 28, 2003 Prepared.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  17. WIND DATA REPORT January -December, 2003

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Vinalhaven January - December, 2003 Prepared for Fox Islands Electric Cooperative...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  18. WIND DATA REPORT January -March, 2004

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Vinalhaven January - March, 2004 Prepared for Fox Islands Electric Cooperative...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  19. WIND DATA REPORT Deer Island Outfall

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Deer Island Outfall August 18, 2003 ­ December 4, 2003 Prepared for Massachusetts...................................................................................................................... 7 Wind Speed Time Series............................................................................................................. 7 Wind Speed Distributions

  20. WIND DATA REPORT Deer Island Parking Lot

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Deer Island Parking Lot May 1, 2003 ­ July 15, 2003 Prepared for Massachusetts...................................................................................................................... 7 Wind Speed Time Series............................................................................................................. 7 Wind Speed Distributions

  1. WIND DATA REPORT Quincy DPW, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Quincy DPW, MA September 1st 2006 to November 30th 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  2. WIND DATA REPORT Bishop and Clerks

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Bishop and Clerks March 1, 2005 ­ May 31, 2005 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  3. WIND DATA REPORT Quincy Quarry Hills

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Quincy Quarry Hills December 2006 to February 2007 Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  4. WIND DATA REPORT Quincy DPW, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Quincy DPW, MA June 1st 2006 to August 31st 2006 Prepared for Massachusetts.................................................................................................................... 11 Wind Speed Time Series........................................................................................................... 11 Wind Speed Distributions

  5. WIND DATA REPORT Quincy Quarry Hills

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Quincy Quarry Hills March 2007 to May 2007 Prepared for Massachusetts Technology...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  6. WIND DATA REPORT Rockport School Complex

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Rockport School Complex Rockport, Massachusetts March 1, 2006 ­ May 31, 2007...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  7. WIND DATA REPORT Quincy DPW, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Quincy DPW, MA March 1st 2007 to May 31st 2007 Prepared for Massachusetts...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  8. WIND DATA REPORT Tisbury, Martha's Vineyard,

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Tisbury, Martha's Vineyard, Massachusetts September 1, 2007 ­ November 30, 2007...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  9. WIND DATA REPORT Rockport School Complex

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Rockport School Complex Rockport, Massachusetts December 1st , 2007 ­ February 29...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  10. WIND DATA REPORT Rockport School Complex

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Rockport School Complex Rockport, Massachusetts September 1, 2005 - November 31.................................................................................................................... 12 Wind Speed Time Series........................................................................................................... 12 Wind Speed Distributions

  11. WIND DATA REPORT Rockport School Complex

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Rockport School Complex Rockport, Massachusetts June 1, 2007 ­ August 31, 2007...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  12. WIND DATA REPORT December, 2004 28th

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Orleans 1st December, 2004 ­28th February, 2005 Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions.......................................................................................................

  13. WIND DATA REPORT Rockport School Complex

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Rockport School Complex Rockport, Massachusetts December 1, 2006 ­ February 28...................................................................................................................... 9 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  14. What is Wind Chill Temperature? It is the temperature it "feels like" outside and is based on the rate of heat loss

    E-Print Network [OSTI]

    What is Wind Chill Temperature? It is the temperature it "feels like" outside and is based on the rate of heat loss from exposed skin caused by the effects of wind and cold. As the wind increases, the body is cooled at a faster rate causing the skin temperature to drop. Wind Chill does not impact

  15. Ris National Laboratory DTU Wind Energy Department

    E-Print Network [OSTI]

    wind speed, wind direction relative to the spinner and flow inclination angle. A wind tunnel concept anemometer is a wind measurement concept in which measurements of wind speed in the flow over a wind turbine on a modified 300kW wind turbine spinner, was mounted with three 1D sonic wind speed sensors. The flow around

  16. INVESTIGATION OF A DYNAMIC POWER LINE RATING CONCEPT FOR IMPROVED WIND ENERGY INTEGRATION OVER COMPLEX TERRAIN

    SciTech Connect (OSTI)

    Jake P. Gentle; Kurt S Myers; Tyler B Phillips; Inanc Senocak; Phil Anderson

    2014-08-01T23:59:59.000Z

    Dynamic Line Rating (DLR) is a smart grid technology that allows the rating of power line to be based on real-time conductor temperature dependent on local weather conditions. In current practice overhead power lines are generally given a conservative rating based on worst case weather conditions. Using historical weather data collected over a test bed area, we demonstrate there is often additional transmission capacity not being utilized with the current static rating practice. We investigate a new dynamic line rating methodology using computational fluid dynamics (CFD) to determine wind conditions along transmission lines at dense intervals. Simulated results are used to determine conductor temperature by calculating the transient thermal response of the conductor under variable environmental conditions. In calculating the conductor temperature, we use both a calculation with steady-state assumption and a transient calculation. Under low wind conditions, steady-state assumption predicts higher conductor temperatures that could lead to curtailments, whereas transient calculations produce conductor temperatures that are significantly lower, implying the availability of additional transmission capacity.

  17. Distributed Compression for Condition Monitoring of Wind Farms

    E-Print Network [OSTI]

    Cheng, Samuel

    wind generation is high due to high wind speeds and import of power where the speeds are low. To make

  18. Long-term-average, solar cycle, and seasonal response of magnetospheric energetic electrons to the solar wind speed

    E-Print Network [OSTI]

    Vassiliadis, Dimitrios

    to the compression of the magnetosphere by the solar wind pressure. Over the solar cycle the variation in solar wind [Boller and Stolov, 1970; Russell and McPherron, 1973; Cliver et al., 2000]. INDEX TERMS: 2730

  19. Abstract--This paper proposes a methodology to decide the optimal matching between the size of the rotor of a wind turbine

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the rotor of a wind turbine and the rated power of a permanent magnet synchronous machine. This is made of the wind turbine, the gearbox's transformation ratio, the battery voltage and the wind speed probability's rated power and the wind turbine's rotor size. The system studied in this paper consists of 220 (V)/50

  20. 20% Wind Energy 20% Wind Energy

    E-Print Network [OSTI]

    Powell, Warren B.

    (government, industry, utilities, NGOs) Analyzes wind's potential contributions to energy security, economic · Transmission a challenge #12;Wind Power Class Resource Potential Wind Power Density at 50 m W/m 2 Wind Speed20% Wind Energy by 2030 20% Wind Energy by 2030 #12;Presentation and Objectives Overview Background

  1. Wind Spires as an Alternative Energy Source

    SciTech Connect (OSTI)

    Majid Rashidi, Ph.D., P.E.

    2012-10-30T23:59:59.000Z

    This report discloses the design and development of an innovative wind tower system having an axisymmetric wind deflecting structure with a plurality of symmetrically mounted rooftop size wind turbines near the axisymmetric structure. The purpose of the wind deflecting structure is to increase the ambient wind speed that in turn results in an overall increase in the power capacity of the wind turbines. Two working prototypes were constructed and installed in the summer of 2009 and 2012 respectively. The system installed in the Summer of 2009 has a cylindrical wind deflecting structure, while the tower installed in 2012 has a spiral-shape wind deflecting structure. Each tower has 4 turbines, each rated at 1.65 KW Name-Plate-Rating. Before fabricating the full-size prototypes, computational fluid dynamic (CFD) analyses and scaled-down table-top models were used to predict the performance of the full-scale models. The performance results obtained from the full-size prototypes validated the results obtained from the computational models and those of the scaled-down models. The second prototype (spiral configuration) showed at a wind speed of 11 miles per hour (4.9 m/s) the power output of the system could reach 1,288 watt, when a typical turbine installation, with no wind deflecting structure, could produce only 200 watt by the same turbines at the same wind speed. At a wind speed of 18 miles per hour (8 m/sec), the spiral prototype produces 6,143 watt, while the power generated by the same turbines would be 1,412 watt in the absence of a wind deflecting structure under the same wind speed. Four US patents were allowed, and are in print, as the results of this project (US 7,540,706, US 7,679,209, US 7,845,904, and US 8,002,516).

  2. Method and apparatus for reducing rotor blade deflections, loads, and/or peak rotational speed

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw; Pierce, Kirk Gee

    2006-10-17T23:59:59.000Z

    A method for reducing at least one of loads, deflections of rotor blades, or peak rotational speed of a wind turbine includes storing recent historical pitch related data, wind related data, or both. The stored recent historical data is analyzed to determine at least one of whether rapid pitching is occurring or whether wind speed decreases are occurring. A minimum pitch, a pitch rate limit, or both are imposed on pitch angle controls of the rotor blades conditioned upon results of the analysis.

  3. WIND DATA REPORT September 1 2003 November 30 2003

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Paxton, MA September 1 2003 ­ November 30 2003 by James F. Manwell Anthony F.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  4. WIND DATA REPORT September 1, 2003 November 31, 2003

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Mt. Tom September 1, 2003 ­ November 31, 2003 Prepared for Massachusetts...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  5. WIND DATA REPORT Camden Hills Regional High School, ME

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Camden Hills Regional High School, ME December 1, 2006 ­ February 28, 2007...................................................................................................................... 7 Wind Speed Time Series............................................................................................................. 8 Wind Speed Distributions

  6. WIND DATA REPORT January 1, 2004 December 31, 2004

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Vinalhaven January 1, 2004 ­ December 31, 2004 Prepared for Fox Islands Electric...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  7. WIND DATA REPORT Camden Hills Regional High School, ME

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Camden Hills Regional High School, ME March 1st 2006 to May 31th 2006 Prepared.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  8. WIND DATA REPORT December 1 2003 February 29 2004

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Paxton, MA December 1 2003 ­ February 29 2004 Prepared for Diane Dillman, Paxton.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  9. WIND DATA REPORT December, 2003 February 29, 2004

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Orleans December, 2003 ­ February 29, 2004 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  10. WIND DATA REPORT Camden Hills Regional High School, ME

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Camden Hills Regional High School, ME September 1st 2006 to November 30th 2006.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  11. WIND DATA REPORT October 27, 2003 November 31, 2003

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Orleans October 27, 2003 ­ November 31, 2003 Prepared for Massachusetts Technology...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  12. WIND DATA REPORT Camden Hills Regional High School, ME

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Camden Hills Regional High School, ME December 1st 2005 to February 28th 2006.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  13. WIND DATA REPORT March 1, 2004 May 31, 2004

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Eastham March 1, 2004 ­ May 31, 2004 Prepared for Massachusetts Technology...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  14. WIND DATA REPORT Camden Hills Regional High School, ME

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Camden Hills Regional High School, ME June 1st 2006 to August 31th 2006 Prepared.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  15. WIND DATA REPORT December 1, 2003 February 29, 2004

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Mt. Tom December 1, 2003 ­ February 29, 2004 Prepared for Massachusetts Technology.................................................................................................................... 10 Wind Speed Time Series........................................................................................................... 10 Wind Speed Distributions

  16. WIND DATA REPORT August 28 -December 31, 2002

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Vinalhaven August 28 - December 31, 2002 Prepared for Fox Islands Electric...................................................................................................................... 9 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  17. Averting Speed Inefficiency in Rate-Diverse WiFi Networks through Queueing and Aggregation

    E-Print Network [OSTI]

    ´in Zubeld´ia, Andr´es Ferragut and Fernando Paganini Universidad ORT Uruguay, Montevideo, Uruguay Abstract is to differentiate traffic classes, not individual station data rates. Research supported by ANII-Uruguay scholarship

  18. Enertech 2-kW high-reliability wind system. Phase II. Fabrication and testing

    SciTech Connect (OSTI)

    Cordes, J A; Johnson, B A

    1981-06-01T23:59:59.000Z

    A high-reliability wind machine rated for 2 kW in a 9 m/s wind has been developed. Activities are summarized that are centered on the fabrication and testing of prototypes of the wind machine. The test results verified that the wind machine met the power output specification and that the variable-pitch rotor effectively controlled the rotor speed for wind speeds up to 50 mph. Three prototypes of the wind machine were shipped to the Rocky Flats test center in September through November of 1979. Work was also performed to reduce the start-up wind speed. The start-up wind speed to the Enertech facility has been reduced to 4.5 m/s.

  19. Variable-Speed Wind Turbine Controller Systematic Design Methodology: A Comparison of Non-Linear and Linear Model-Based Designs

    SciTech Connect (OSTI)

    Hand, M. M.

    1999-07-30T23:59:59.000Z

    Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three regions of operation. This paper focuses on controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative (PID) controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship of the two opposing metrics is easily visualized. Traditional controller design generally consists of linearizing a model about an operating point. This step was taken for two different operating points, and the systematic design approach was used. A comparison of the optimal regions selected using the n on-linear model and the two linear models shows similarities. The linearization point selection does, however, affect the turbine performance slightly. Exploitation of the simplicity of the model allows surfaces consisting of operation under a wide range of gain values to be created. This methodology provides a means of visually observing turbine performance based upon the two metrics chosen for this study. Design of a PID controller is simplified, and it is possible to ascertain the best possible combination of controller parameters. The wide, flat surfaces indicate that a PID controller is very robust in this variable-speed wind turbine application.

  20. Variation in rectal temperature, respiratory rate, and pulse rate of cattle as related to variations in solar radiation, air temperature, wind velocity, and vapor pressure

    E-Print Network [OSTI]

    Quazi, Mohammad Fazlur Rahim

    1955-01-01T23:59:59.000Z

    VARIATION IN RECTAL TEMPERATURE, RESPIRATORY RATE, AND PULSE RATE GF CATTLE AS RELATED TO VARIATIONS IN SOLAR RADIATION, AIR TEMPERATURE, WIND VELOCITY, AND VAPOR PRESSURE A Dissertation By Mohammad Fazlur Rahim Quazi Approved as to style... Dissertation By Mohammad Fazlur Rahim tyiazi Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 1955 Major Subject: Genetics ? ?4...

  1. Effects of Changing Atmospheric Conditions on Wind Turbine Performance (Poster)

    SciTech Connect (OSTI)

    Clifton, A.

    2012-12-01T23:59:59.000Z

    Multi-megawatt, utility-scale wind turbines operate in turbulent and dynamic winds that impact turbine performance in ways that are gradually becoming better understood. This poster presents a study made using a turbulent flow field simulator (TurbSim) and a Turbine aeroelastic simulator (FAST) of the response of a generic 1.5 MW wind turbine to changing inflow. The turbine power output is found to be most sensitive to wind speed and turbulence intensity, but the relationship depends on the wind speed with respect to the turbine's rated wind speed. Shear is found to be poorly correlated to power. A machine learning method called 'regression trees' is used to create a simple model of turbine performance that could be used as part of the wind resource assessment process. This study has used simple flow fields and should be extended to more complex flows, and validated with field observations.

  2. Low Speed Technology for Small Turbine Development Reaction Injection Molded 7.5 Meter Wind Turbine Blade

    SciTech Connect (OSTI)

    David M. Wright; DOE Project Officer - Keith Bennett

    2007-07-31T23:59:59.000Z

    An optimized small turbine blade (7.5m radius) was designed and a partial section molded with the RIM (reaction-injection molded polymer) process for mass production. The intended market is for generic three-bladed wind turbines, 100 kilowatts or less, for grid-assist end users with rural and semi-rural sites, such as the farm/ranch market, having low to moderate IEC Class 3-4 wind regimes. This blade will have substantial performance improvements over, and be cheaper than, present-day 7.5m blades. This is made possible by the injection-molding process, which yields high repeatability, accurate geometry and weights, and low cost in production quantities. No wind turbine blade in the 7.5m or greater size has used this process. The blade design chosen uses a RIM skin bonded to a braided infused carbon fiber/epoxy spar. This approach is attractive to present users of wind turbine blades in the 5-10m sizes. These include rebladeing California wind farms, refurbishing used turbines for the Midwest farm market, and other manufacturers introducing new turbines in this size range.

  3. Performance Indicators of Wind Energy Production

    E-Print Network [OSTI]

    D'Amico, G; Prattico, F

    2015-01-01T23:59:59.000Z

    Modeling wind speed is one of the key element when dealing with the production of energy through wind turbines. A good model can be used for forecasting, site evaluation, turbines design and many other purposes. In this work we are interested in the analysis of the future financial cash flows generated by selling the electrical energy produced. We apply an indexed semi-Markov model of wind speed that has been shown, in previous investigation, to reproduce accurately the statistical behavior of wind speed. The model is applied to the evaluation of financial indicators like the Internal Rate of Return, semi-Elasticity and relative Convexity that are widely used for the assessment of the profitability of an investment and for the measurement and analysis of interest rate risk. We compare the computation of these indicators for real and synthetic data. Moreover, we propose a new indicator that can be used to compare the degree of utilization of different power plants.

  4. Strong wind forcing of the ocean

    E-Print Network [OSTI]

    Zedler, Sarah E.

    2007-01-01T23:59:59.000Z

    of mesoscale and steady wind driven 1. Introduction 2. Modelparameterization at high wind speeds 1. Introduction 2. DataSupplementary Formulae 1. Wind Stress 2. Rankine Vortex A .

  5. Optimal Wind Conditions for the Survival of Larval Northern Anchovy, Engraulis mordax

    E-Print Network [OSTI]

    . There is a statistically sig- nificant relation between larva mortality rate and the frequency of calm, low wind speed periOptimal Wind Conditions for the Survival of Larval Northern Anchovy, Engraulis mordax: A Modeling- puter modeling. The hypothesis was as follows. While wind events dissipate layers of planktonic food

  6. Low Speed Virtual Wind Tunnel Simulation For Educational Studies In Introducing Computational Fluid Dynamics And Flow Visualization

    E-Print Network [OSTI]

    Yang, Cher-Chiang

    2008-05-05T23:59:59.000Z

    ............................................................................................................... 25 3.2.4. Starting FlowLab ...................................................................................................................... 26 3.2.5. Geometry Settings... OF THE PROGRAMMING....................................................................... 52 v List of Figures FIGURE 2.1 ? COST AND TIME RELATIONSHIP WITH RESPECT TO CFD AND WIND TUNNELS............................. 5 FIGURE 2.2 - BOEING 777 DESIGN...

  7. Generation of ultrahigh-speed tunable-rate optical pulses using strongly gain-coupled dual-wavelength DFB laser diodes

    E-Print Network [OSTI]

    Hui, Rongqing; Zhu, B.; Demarest, Kenneth; Allen, Christopher Thomas; Hong, Jin

    1999-05-01T23:59:59.000Z

    A novel and simple method to generate a variable-rate, ultrahigh-speed optical pulse train is demonstrated using a dual-wavelength, strongly gain-coupled distributed-feedback laser diode, The repetition rate of the optical pulse train...

  8. Low Wind Speed Turbine Project Conceptual Design Study: Advanced Independent Pitch Control; July 30, 2002--July 31, 2004 (Revised)

    SciTech Connect (OSTI)

    Olsen, T.; Lang, E.; Hansen, A.C.; Cheney, M. C.; Quandt, G.; VandenBosche, J.; Meyer, T.

    2004-12-01T23:59:59.000Z

    AES conducted a conceptual study of independent pitch control using inflow angle sensors. The control strategy combined input from turbine states (rotor speed, rotor azimuth, each blade pitch) with inflow angle measurements (each blade angle of attack at station 11 of 15) to derive blade pitch demand signals. The controller reduced loads sufficiently to allow a 10% rotor extension and reduce COE by 6.3%.

  9. WP2 IEA Wind Task 26:The Past and Future Cost of Wind Energy

    E-Print Network [OSTI]

    Lantz, Eric

    2014-01-01T23:59:59.000Z

    Energy Efficiency and Renewable Energy, Wind and HydropowerSpeed Sites. ” European Wind Energy Association. Marseille,Innovation and the price of wind energy in the US. ” Energy

  10. WP2 IEA Wind Task 26:The Past and Future Cost of Wind Energy

    E-Print Network [OSTI]

    Lantz, Eric

    2014-01-01T23:59:59.000Z

    Speed Sites. ” European Wind Energy Association. Marseille,Innovation and the price of wind energy in the US. ” EnergyThe Economics of Wind Energy. ” Renewable and Sustainable

  11. Toward Controlled Wind Farm Output: Adjustable Power Filtering

    E-Print Network [OSTI]

    Lehn, Peter W.

    wind energy is extracted by the turbine blades. CP depends on the tip-speed ratio, , defined as = Rh structure for a fully-rated converter interfaced wind turbine. A singular perturbations decomposition the static curve that describes the aerodynamic conversion of energy by the bladed turbine rotor

  12. Wind/Hybrid Electricity Applications

    SciTech Connect (OSTI)

    McDaniel, Lori

    2001-03-31T23:59:59.000Z

    Wind energy is widely recognized as the most efficient and cost effective form of new renewable energy available in the Midwest. New utility-scale wind farms (arrays of large turbines in high wind areas producing sufficient energy to serve thousands of homes) rival the cost of building new conventional forms of combustion energy plants, gas, diesel and coal power plants. Wind energy is not subject to the inflationary cost of fossil fuels. Wind energy can also be very attractive to residential and commercial electric customers in high wind areas who would like to be more self-sufficient for their energy needs. And wind energy is friendly to the environment at a time when there is increasing concern about pollution and climate change. However, wind energy is an intermittent source of power. Most wind turbines start producing small amounts of electricity at about 8-10 mph (4 meters per second) of wind speed. The turbine does not reach its rated output until the wind reaches about 26-28 mph (12 m/s). So what do you do for power when the output of the wind turbine is not sufficient to meet the demand for energy? This paper will discuss wind hybrid technology options that mix wind with other power sources and storage devices to help solve this problem. This will be done on a variety of scales on the impact of wind energy on the utility system as a whole, and on the commercial and small-scale residential applications. The average cost and cost-benefit of each application along with references to manufacturers will be given. Emerging technologies that promise to shape the future of renewable energy will be explored as well.

  13. Stellar Winds on the Main-Sequence I: Wind Model

    E-Print Network [OSTI]

    Johnstone, C P; Lüftinger, T; Toth, G; Brott, I

    2015-01-01T23:59:59.000Z

    Aims: We develop a method for estimating the properties of stellar winds for low-mass main-sequence stars between masses of 0.4 and 1.1 solar masses at a range of distances from the star. Methods: We use 1D thermal pressure driven hydrodynamic wind models run using the Versatile Advection Code. Using in situ measurements of the solar wind, we produce models for the slow and fast components of the solar wind. We consider two radically different methods for scaling the base temperature of the wind to other stars: in Model A, we assume that wind temperatures are fundamentally linked to coronal temperatures, and in Model B, we assume that the sound speed at the base of the wind is a fixed fraction of the escape velocity. In Paper II of this series, we use observationally constrained rotational evolution models to derive wind mass loss rates. Results: Our model for the solar wind provides an excellent description of the real solar wind far from the solar surface, but is unrealistic within the solar corona. We run ...

  14. WIND DATA REPORT WBZ Tower, Hull, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT WBZ Tower, Hull, MA 12/1/06-2/28/07 Prepared for Department of Energy (DOE) Golden...................................................................................................................... 8 Wind Speed Time Series............................................................................................................. 9 Wind Speed Distributions

  15. Airâ??sea dimethylsulfide (DMS) gas transfer in the North Atlantic: evidence for limited interfacial gas exchange at high wind speed

    E-Print Network [OSTI]

    Bell, T. G; De Bruyn, W.; Miller, S. D; Ward, B.; Christensen, K.; Saltzman, E. S

    2013-01-01T23:59:59.000Z

    O. : Modulation of short wind waves by long waves, J.P. , and Donelan, M. A. : Wind stress in the presence ofunder moderate to strong wind conditions, J. Geophys. Res. -

  16. Speeding up protein folding: mutations that increase the rate at which Rop folds and unfolds by over four orders of magnitude

    E-Print Network [OSTI]

    Mochrie, Simon

    Speeding up protein folding: mutations that increase the rate at which Rop folds and unfolds. Introduction When a protein folds, the backbone and sidechain atoms organize from the extensive number protein folding usually occurs on the order of milliseconds to seconds, it is gener- ally accepted

  17. Offshore Wind Project Surges Ahead in South Carolina

    Broader source: Energy.gov [DOE]

    The Center for Marine and Wetland Studies studies wind speed data from buoys, which have been measuring wind speed and direction for the past year.

  18. annual wind river: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    with the strength of the interplanetary magnetic field (IMF) and the solar wind speed, respectively, because solar wind speed is the most important parameter driving...

  19. On the measurement of wind speeds in tornadoes with a portable CW/FM-CW Doppler radar

    SciTech Connect (OSTI)

    Bluestein, H.B. (Oklahoma Univ., Norman, OK (USA). School of Meteorology); Unruh, W.P. (Los Alamos National Lab., NM (USA))

    1991-01-01T23:59:59.000Z

    Both the formation mechanism and structure of tornadoes are not yet well understood. The Doppler radar is probably the best remote-sensing instrument at present for determining the wind field in tornadoes. Although much has been learned about the non-supercell tornado from relatively close range using Doppler radars at fixed sites, close-range measurements in supercell tornadoes are relatively few. Doppler radar can increase significantly the number of high-resolution, sub-cloud base measurements of both the tornado vortex and its parent vortex in supercells, with simultaneous visual documentation. The design details and operation of the CW/FM-CW Doppler radar developed at the Los Alamos National Laboratory and used by storm-intercept teams at the Univ. of Oklahoma are described elsewhere. The radar transmits 1 W at 3 cm, and can be switched back and forth between CW and FM-CW modes. In the FM-CW mode the sweep repetition frequency is 15.575 kHz and the sweep width 1.9 MHz; the corresponding maximum unambiguous range and velocity, and range resolution are 5 km, {plus minus} 115 m s{sup {minus}1}, and 78 m respectively. The bistatic antennas, which have half-power beamwidths of 5{degree}, are easily pointed wit the aid of a boresighted VCR. FM-CW Data are recorded on the VCR, while voice documentation is recorded on the audio tape; video is recorded on another VCR. The radar and antennas are easily mounted on a tripod, and can be set up by three people in a minute or two. The purpose of this paper is to describe the signal processing techniques used to determine the Doppler spectrum in the FM-CW mode and a method of its interpretation in real time, and to present data gathered in a tornadic storm in 1990. 15 refs., 7 figs.

  20. 2012 Wind Technologies Market Report

    E-Print Network [OSTI]

    Wiser, Ryan

    2014-01-01T23:59:59.000Z

    regulation and frequency response services charge to wind energyRegulation and Frequency Response Service rate for wind energy

  1. Airplane and the wind

    E-Print Network [OSTI]

    Airplane and the wind. An airplane starts from the point A and flies to B. The speed of the airplane with respect to the air is v (constant). There is also a wind of

  2. Distributed Wind Diffusion Model Overview (Presentation)

    SciTech Connect (OSTI)

    Preus, R.; Drury, E.; Sigrin, B.; Gleason, M.

    2014-07-01T23:59:59.000Z

    Distributed wind market demand is driven by current and future wind price and performance, along with several non-price market factors like financing terms, retail electricity rates and rate structures, future wind incentives, and others. We developed a new distributed wind technology diffusion model for the contiguous United States that combines hourly wind speed data at 200m resolution with high resolution electricity load data for various consumer segments (e.g., residential, commercial, industrial), electricity rates and rate structures for utility service territories, incentive data, and high resolution tree cover. The model first calculates the economics of distributed wind at high spatial resolution for each market segment, and then uses a Bass diffusion framework to estimate the evolution of market demand over time. The model provides a fundamental new tool for characterizing how distributed wind market potential could be impacted by a range of future conditions, such as electricity price escalations, improvements in wind generator performance and installed cost, and new financing structures. This paper describes model methodology and presents sample results for distributed wind market potential in the contiguous U.S. through 2050.

  3. Global ocean wind power sensitivity to surface layer stability

    E-Print Network [OSTI]

    Capps, Scott B; Zender, Charles S

    2009-01-01T23:59:59.000Z

    2005), Evaluation of global wind power, J. Geophys. Res. ,Pryor (2003), Can satellite sampling of offshore wind speedsrealistically represent wind speed distributions? , J. Appl.

  4. Abstract--A bi-objective optimization model of power and power changes generated by a wind turbine is discussed in this

    E-Print Network [OSTI]

    Kusiak, Andrew

    operating a variable-speed wind turbine with pitch control to maximize power while minimizing the loads prediction, power ramp rate, data mining, wind turbine operation strategy, generator torque, blade pitch1 Abstract--A bi-objective optimization model of power and power changes generated by a wind

  5. RELIABILITY OF WIND POWER FROM DISPERSED SITES: A PRELIMINARY ASSESSMENT

    E-Print Network [OSTI]

    Kahn, E.

    2011-01-01T23:59:59.000Z

    PG&E 4:00 p.m. Summer Wind Generator Model Wind Array ELCCexpect from an array of wind generators spread over a largean array of dispersed wind generators will be. wind speed

  6. Technology Improvement Opportunities for Low Wind Speed Turbines and Implications for Cost of Energy Reduction: July 9, 2005 - July 8, 2006

    SciTech Connect (OSTI)

    Cohen, J.; Schweizer, T.; Laxson, A.; Butterfield, S.; Schreck, S.; Fingersh, L.; Veers, P.; Ashwill, T.

    2008-02-01T23:59:59.000Z

    This report analyzes the status of wind energy technology in 2002 and describes the potential for technology advancements to reduce the cost and increase the performance of wind turbines.

  7. Wind energy conversion system

    DOE Patents [OSTI]

    Longrigg, Paul (Golden, CO)

    1987-01-01T23:59:59.000Z

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  8. Wind turbine

    DOE Patents [OSTI]

    Cheney, Jr., Marvin C. (Glastonbury, CT)

    1982-01-01T23:59:59.000Z

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

  9. WP2 IEA Wind Task 26:The Past and Future Cost of Wind Energy

    E-Print Network [OSTI]

    Lantz, Eric

    2014-01-01T23:59:59.000Z

    Bolinger, M. ( 2011). 2010 Wind Technologies Market Report.Cost of Energy From U.S. Wind Power Projects. Presentationand Energy Capture at Low Wind Speed Sites. ” European Wind

  10. Effect of rate of current rise in the output windings on the space -time distribution of the electron beam in a betatron

    SciTech Connect (OSTI)

    Chakhlov, V.L.; Filimonov, A.A.; Kashkovskii, V.V.

    1985-09-01T23:59:59.000Z

    This paper reports on the results of a study of the effect of the rate of current rise in the output windings of a betatron on the parameters of the resultant electron beam. It is shown that the rate of current rise in the windings only changes the duration of the radiation pulse associated with the beam and its delay relative to the initiation of the current pulse in the windings. The spatial distribution of the beam is determined mainly by the distribution of the magnetic field of the betatron. The findings of this study have made it possible to simplify the current pulse generator in the output-winding supply circuit of the PMB-6E betatron, reduce its size, and increase its reliability.

  11. WIND DATA REPORT WBZ Tower, Hull, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT WBZ Tower, Hull, MA 9/1/06-11/30/06 Prepared for Department of Energy (DOE) Golden.................................................................................................................... 10 Wind Speed Time Series...........................................................................................................

  12. WIND DATA REPORT Quincy, Quarry Hills

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT Quincy, Quarry Hills 9/1/2006 ­ 11/30/2006 Prepared for Massachusetts Technology.......................................................................................................................... 7 Tower Effects on Measured Wind Speed

  13. WIND DATA REPORT WBZ Tower, Hull, MA

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    WIND DATA REPORT WBZ Tower, Hull, MA 11/13/06-11/30/06 Prepared for Department of Energy (DOE.................................................................................................................... 10 Wind Speed Time Series.........................................................................................................

  14. Resuspension rates from aged inert-tracer sources

    SciTech Connect (OSTI)

    Sehmel, G.A.

    1982-11-01T23:59:59.000Z

    Wind-caused particle resuspension rates were investigated with molybdenum tracers at two circular resuspension sites in the Hanford area. The tracer particles were calcium molybdate. The radii of each circular tracer-source area were 22.9 m and 29.9 m respectively for tracer deposited on 2 October 1973 and 29 May 1979. Resuspension rates were investigated by sampling resuspended tracer with air sampling equipment mounted as a function of height on a centrally located sampling tower at each site. Sampling equipment was operated as a function of wind speed increments in order to investigate resuspension rates, wind speed dependencies of resuspension rates, and for subsequent comparisons of resuspension rate changes as a function of time for constant wind speed ranges. Experimental results are reported for measurements over several years. Resuspension rates ranged from about 10/sup -13/ to 10/sup -6/ fraction of the tracer source resuspended per second. Resuspension rates tended to increase with increasing wind speed. At one investigation site, resuspension rates were nearly constant, except for seasonal variations, for a four-year time period. Resuspension rates appear higher in the autumn than in the spring and summer.

  15. Double Side Control of Wound Rotor Induction Machine for Wind Energy Application Employing Half Controlled

    E-Print Network [OSTI]

    Lipo, Thomas

    the cost of a wind generator system, a new configuration using half controlled converters for both the required KVA rating of both machine side and line side converters, improves the efficiency of the wind generator, helps operating over a wide speed range and supports near unity power factor interface

  16. RATES

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Planning & Projects Power Marketing Rates You are here: SN Home page > Power Marketing > RATES Rates and Repayment Services Rates Current Rates FY 15 PRR worksheet (PDF - 31K) FY...

  17. Low Wind Speed Technology Phase II: Design and Demonstration of On-Site Fabrication of Fluted-Steel Towers Using LITS-Form(TM) Process

    SciTech Connect (OSTI)

    Not Available

    2006-06-01T23:59:59.000Z

    This fact sheet describes NREL's subcontract with Native American Technologies to develop a new method of metal plate forming to produce wind turbine towers.

  18. RATES

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    RATES Rates Document Library SNR Rates Process Calendar (PDF - 171K) Procedures Informal Process Transmission Action Items List (PDF - 144K) Power Action Item List updated on...

  19. Compact Radio Sources within 30" of Sgr A*: Proper Motions, Stellar Winds and the Accretion Rate onto Sgr A*

    E-Print Network [OSTI]

    Yusef-Zadeh, F; Schödel, R; Wardle, M; Cotton, W; Roberts, D A; Nogueras-Lara, F; Gallego-Cano, E

    2015-01-01T23:59:59.000Z

    Recent broad-band 34 and 44 GHz radio continuum observations of the Galactic center have revealed 41 massive stars identified with near-IR counterparts, as well as 44 proplyd candidates within 30" of Sgr A*. Radio observations obtained in 2011 and 2014 have been used to derive proper motions of eight young stars near Sgr A*. The accuracy of proper motion estimates based on near-IR observations by Lu et al. and Paumard et al. have been investigated by using their proper motions to predict the 2014 epoch positions of near-IR stars and comparing the predicted positions with those of radio counterparts in the 2014 radio observations. Predicted positions from Lu et al. show an rms scatter of 6 mas relative to the radio positions, while those from Paumard et al. show rms residuals of 20 mas, which is mainly due to uncertainties in the IR-based proper motions. Under the assumption of homogeneous ionized winds, we also determine the mass-loss rates of 11 radio stars, finding rates that are on average $\\sim$2 times sm...

  20. EXPERIENCES WITH SONIC WIND SENSORS IN OPERATIONAL CONDITIONS Wiel M.F. Wauben

    E-Print Network [OSTI]

    Wauben, Wiel

    ) uses conventional cup anemometers and wind vanes to measure wind speed and direction. Although the KNMI sonic considered in the previous evaluation. The advanced sensor has the required wind speed range up. An uncertainty of the wind speed of maximally 2 % at all wind directions is required for the wind profile

  1. Wind Resource Assessment in Europe Using Emergy

    E-Print Network [OSTI]

    Paudel, Subodh; Santarelli, Massimo; Martin, Viktoria; Lacarriere, Bruno; Le Corre, Olivier

    2014-01-01T23:59:59.000Z

    to change in upstream and downstream wind speed from 850 kW,1650 kW and 3000 kW wind turbinesseJ/J) Transformity of Wind Turbine (1650kW) Latitude

  2. The Solar Wind Energy Flux

    E-Print Network [OSTI]

    Chat, G Le; Meyer-Vernet, N

    2012-01-01T23:59:59.000Z

    The solar-wind energy flux measured near the ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10%, and that this quantity varies weakly over the solar cycle. In other words the energy flux appears as a global solar constant. We also show that the very high speed solar-wind (VSW > 700 km/s) has the same mean energy flux as the slower wind (VSW < 700 km/s), but with a different histogram. We use this result to deduce a relation between the solar-wind speed and density, which formalizes the anti-correlation between these quantities.

  3. RATES

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Marketing > RATES RATES Current Rates Past Rates 2006 2007 2008 2009 2010 2011 2012 Rates Schedules Power CV-F13 CPP-2 Transmissions CV-T3 CV-NWT5 PACI-T3 COTP-T3 CV-TPT7 CV-UUP1...

  4. Wind Technology Advancements and Impacts on Western Wind Resources (Presentation)

    SciTech Connect (OSTI)

    Robichaud, R.

    2014-09-01T23:59:59.000Z

    Robi Robichaud made this presentation at the Bureau of Land Management West-wide Wind Opportunities and Constraints Mapping (WWOCM) Project public meeting in Denver, Colorado in September 2014. This presentation outlines recent wind technology advancements, evolving turbine technologies, and industry challenges. The presentation includes maps of mean wind speeds at 50-m, 80-m, and 100-m hub heights on BLM lands. Robichaud also presented on the difference in mean wind speeds from 80m to 100m in Wyoming.

  5. Design and Test of a Variable Speed Wind Turbine System Employing a Direct Drive Axial Flux Synchronization Generator: 29 October 2002 - 31 December 2005

    SciTech Connect (OSTI)

    Lipo, T. A.; Tenca, P.

    2006-07-01T23:59:59.000Z

    The goal of this funded research project is the definition, analytical investigation, modeling, and prototype realization of a current-source conversion topology tailored to high-power wind turbines.

  6. Design and Test of DC Voltage Link Conversion System and Brushless Doubly-Fed Induction Generator for Variable-Speed Wind Energy Applications: August 1999--May 2003

    SciTech Connect (OSTI)

    Lipo, T.A.; Panda, D.; Zarko, D.

    2005-11-01T23:59:59.000Z

    This report describes four low-cost alternative power converters for processing the power developed by a doubly fed wound-rotor induction generator for wind energy conversion systems.

  7. Contrasting controls on wildland fires in Southern California during periods with and without Santa Ana winds

    E-Print Network [OSTI]

    Jin, Yufang; Randerson, James T; Faivre, Nicolas; Capps, Scott; Hall, Alex; Goulden, Michael L

    2014-01-01T23:59:59.000Z

    conditions, when strong offshore winds and low humidity leadat locations with high offshore wind speeds [Moritz et al. ,res, driven by sustained offshore extreme winds beginning 20

  8. Synoptic and local influences on boundary layer processes, with an application to California wind power

    E-Print Network [OSTI]

    Mansbach, David K.

    2010-01-01T23:59:59.000Z

    3.4.2 Wind roses . . . . . . . .Figure 5.5: Downscaled wind speed changes and componentin?uences on California’s wind energy resource. Part 1:

  9. Analyzing Effects of Turbulence on Power Generation Using Wind Plant Monitoring Data: Preprint

    SciTech Connect (OSTI)

    Zhang, J.; Chowdhury, S.; Hodge, B. M.

    2014-01-01T23:59:59.000Z

    In this paper, a methodology is developed to analyze how ambient and wake turbulence affects the power generation of a single wind turbine within an array of turbines. Using monitoring data from a wind power plant, we selected two sets of wind and power data for turbines on the edge of the wind plant that resemble (i) an out-of-wake scenario (i.e., when the turbine directly faces incoming winds) and (ii) an in-wake scenario (i.e., when the turbine is under the wake of other turbines). For each set of data, two surrogate models were then developed to represent the turbine power generation (i) as a function of the wind speed; and (ii) as a function of the wind speed and turbulence intensity. Support vector regression was adopted for the development of the surrogate models. Three types of uncertainties in the turbine power generation were also investigated: (i) the uncertainty in power generation with respect to the published/reported power curve, (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) under the same wind conditions, the turbine generates different power between the in-wake and out-of-wake scenarios, (ii) a turbine generally produces more power under the in-wake scenario than under the out-of-wake scenario, (iii) the power generation is sensitive to turbulence intensity even when the wind speed is greater than the turbine rated speed, and (iv) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.

  10. WP2 IEA Wind Task 26:The Past and Future Cost of Wind Energy

    E-Print Network [OSTI]

    Lantz, Eric

    2014-01-01T23:59:59.000Z

    G. ; Zervos, A. (2011). Wind Energy. In IPCC Special ReportSpeed Sites. ” European Wind Energy Association. Marseille,Innovation and the price of wind energy in the US. ” Energy

  11. 2011 Wind Technologies Market Report

    E-Print Network [OSTI]

    Bolinger, Mark

    2013-01-01T23:59:59.000Z

    regulation and frequency response services charge for wind energyRegulation and Frequency Response Service that charges a higher rate for wind energy

  12. International Statistical Review (2012), 80, 1, 223 doi:10.1111/j.1751-5823.2011.00168.x Short-Term Wind Speed Forecasting

    E-Print Network [OSTI]

    Genton, Marc G.

    2012-01-01T23:59:59.000Z

    the overall energy consumption by 20% through improved energy efficiency by 2020; see European Union (EU of Statistics, Texas A&M University, College Station, TX 77843-3143, USA E-mails: xzhu@stat.tamu.edu, genton@stat.tamu.edu Summary The emphasis on renewable energy and concerns about the environment have led to large-scale wind

  13. accretion disk winds: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and can obtain radiatively driven winds accelerated up to the it relativistic speed. For less luminous cases, disk winds are transonic types passing through saddle type...

  14. accretion disk wind: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and can obtain radiatively driven winds accelerated up to the it relativistic speed. For less luminous cases, disk winds are transonic types passing through saddle type...

  15. Conversion Topology for Reducing Failure Rate and Life-Cycle Costs of High-Power Wind Turbines

    E-Print Network [OSTI]

    Lipo, Thomas

    Drive Madison, WI 53706 #12;American Institute of Aeronautics and Astronautics 1 Conversion Topology;American Institute of Aeronautics and Astronautics 2 I. Introduction ARGE multi-megawatt wind turbines

  16. Wind Development on Tribal Lands

    SciTech Connect (OSTI)

    Ken Haukaas; Dale Osborn; Belvin Pete

    2008-01-18T23:59:59.000Z

    Background: The Rosebud Sioux Tribe (RST) is located in south central South Dakota near the Nebraska border. The nearest community of size is Valentine, Nebraska. The RST is a recipient of several Department of Energy grants, written by Distributed Generation Systems, Inc. (Disgen), for the purposes of assessing the feasibility of its wind resource and subsequently to fund the development of the project. Disgen, as the contracting entity to the RST for this project, has completed all the pre-construction activities, with the exception of the power purchase agreement and interconnection agreement, to commence financing and construction of the project. The focus of this financing is to maximize the economic benefits to the RST while achieving commercially reasonable rates of return and fees for the other parties involved. Each of the development activities required and its status is discussed below. Land Resource: The Owl Feather War Bonnet 30 MW Wind Project is located on RST Tribal Trust Land of approximately 680 acres adjacent to the community of St. Francis, South Dakota. The RST Tribal Council has voted on several occasions for the development of this land for wind energy purposes, as has the District of St. Francis. Actual footprint of wind farm will be approx. 50 acres. Wind Resource Assessment: The wind data has been collected from the site since May 1, 2001 and continues to be collected and analyzed. The latest projections indicate a net capacity factor of 42% at a hub height of 80 meters. The data has been collected utilizing an NRG 9300 Data logger System with instrumentation installed at 30, 40 and 65 meters on an existing KINI radio tower. The long-term annual average wind speed at 65-meters above ground level is 18.2 mph (8.1 mps) and 18.7 mph (8.4 mps) at 80-meters agl. The wind resource is excellent and supports project financing.

  17. agb stellar winds: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    variations in the location and appearance of the critical curves where the wind speed equals the slow, Alfven, and fast speed. Larger dead zones cause effective, fairly...

  18. Wind Generation on Winnebago Tribal Lands

    SciTech Connect (OSTI)

    Multiple

    2009-09-30T23:59:59.000Z

    The Winnebago Wind Energy Study evaluated facility-scale, community-scale and commercial-scale wind development on Winnebago Tribal lands in northeastern Nebraska. The Winnebago Tribe of Nebraska has been pursuing wind development in various forms for nearly ten years. Wind monitoring utilizing loaned met towers from NREL took place during two different periods. From April 2001 to April 2002, a 20-meter met tower monitored wind data at the WinnaVegas Casino on the far eastern edge of the Winnebago reservation in Iowa. In late 2006, a 50-meter tower was installed, and subsequently monitored wind data at the WinnaVegas site from late 2006 through late 2008. Significant challenges with the NREL wind monitoring equipment limited the availability of valid data, but based on the available data, average wind speeds between 13.6 – 14.3 miles were indicated, reflecting a 2+/3- wind class. Based on the anticipated cost of energy produced by a WinnaVegas wind turbine, and the utility policies and rates in place at this time, a WinnaVegas wind project did not appear to make economic sense. However, if substantial grant funding were available for energy equipment at the casino site, and if either Woodbury REC backup rates were lower, or NIPCO was willing to pay more for wind power, a WinnaVegas wind project could be feasible. With funding remaining in the DOE-funded project budget,a number of other possible wind project locations on the Winnebago reservation were considered. in early 2009, a NPPD-owned met tower was installed at a site identified in the study pursuant to a verbal agreement with NPPD which provided for power from any ultimately developed project on the Western Winnebago site to be sold to NPPD. Results from the first seven months of wind monitoring at the Western Winnebago site were as expected at just over 7 meters per second at 50-meter tower height, reflecting Class 4 wind speeds, adequate for commercial development. If wind data collected in the remaining months of the twelve-month collection period is consistent with that collected in the first seven months, the Western Winnebago site may present an interesting opportunity for Winnebago. Given the distance to nearby substations, and high cost of interconnection at higher voltage transmission lines, Winnebago would likely need to be part of a larger project in order to reduce power costs to more attractive levels. Another alternative would be to pursue grant funding for a portion of development or equipment costs, which would also help reduce the cost of power produced. The NREL tower from the WinnaVegas site was taken down in late 2008, re-instrumented and installation attempted on the Thunderway site south of the Winnebago community. Based on projected wind speeds, current equipment costs, and the project’s proximity to substations for possible interconnection, a Thunderway community-scale wind project could also be feasible.

  19. Wind motor applications for transportation

    SciTech Connect (OSTI)

    Lysenko, G.P.; Grigoriev, B.V.; Karpin, K.B. [Moscow Aviation Inst. (Russian Federation)

    1996-12-31T23:59:59.000Z

    Motion equation for a vehicle equipped with a wind motor allows, taking into account the drag coefficients, to determine the optimal wind drag velocity in the wind motor`s plane, and hence, obtain all the necessary data for the wind wheel blades geometrical parameters definition. This optimal drag velocity significantly differs from the flow drag velocity which determines the maximum wind motor power. Solution of the motion equation with low drag coefficients indicates that the vehicle speed against the wind may be twice as the wind speed. One of possible transportation wind motor applications is its use on various ships. A ship with such a wind motor may be substantially easier to steer, and if certain devices are available, may proceed in autonomous control mode. Besides, it is capable of moving within narrow fairways. The cruise speed of a sailing boat and wind-motored ship were compared provided that the wind velocity direction changes along a harmonic law with regard to the motion direction. Mean dimensionless speed of the wind-motored ship appears to be by 20--25% higher than that of a sailing boat. There was analyzed a possibility of using the wind motors on planet rovers in Mars or Venus atmospheric conditions. A Mars rover power and motor system has been assessed for the power level of 3 kW.

  20. Methods and apparatus for reducing peak wind turbine loads

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw

    2007-02-13T23:59:59.000Z

    A method for reducing peak loads of wind turbines in a changing wind environment includes measuring or estimating an instantaneous wind speed and direction at the wind turbine and determining a yaw error of the wind turbine relative to the measured instantaneous wind direction. The method further includes comparing the yaw error to a yaw error trigger that has different values at different wind speeds and shutting down the wind turbine when the yaw error exceeds the yaw error trigger corresponding to the measured or estimated instantaneous wind speed.

  1. Wind Resource Assessment of Gujarat (India)

    SciTech Connect (OSTI)

    Draxl, C.; Purkayastha, A.; Parker, Z.

    2014-07-01T23:59:59.000Z

    India is one of the largest wind energy markets in the world. In 1986 Gujarat was the first Indian state to install a wind power project. In February 2013, the installed wind capacity in Gujarat was 3,093 MW. Due to the uncertainty around existing wind energy assessments in India, this analysis uses the Weather Research and Forecasting (WRF) model to simulate the wind at current hub heights for one year to provide more precise estimates of wind resources in Gujarat. The WRF model allows for accurate simulations of winds near the surface and at heights important for wind energy purposes. While previous resource assessments published wind power density, we focus on average wind speeds, which can be converted to wind power densities by the user with methods of their choice. The wind resource estimates in this study show regions with average annual wind speeds of more than 8 m/s.

  2. Dynamic valuation model For wind development in regard to land value, proximity to transmission lines, and capacity factor

    E-Print Network [OSTI]

    Nikandrou, Paul

    2009-01-01T23:59:59.000Z

    Developing a wind farm involves many variables that can make or break the success of a potential wind farm project. Some variables such as wind data (capacity factor, wind rose, wind speed, etc.) are readily available in ...

  3. A doubly-fed permanent magnet generator for wind turbines

    E-Print Network [OSTI]

    Thomas, Andrew J. (Andrew Joseph), 1981-

    2004-01-01T23:59:59.000Z

    Optimum extraction of energy from a wind turbine requires that turbine speed vary with wind speed. Existing solutions to produce constant-frequency electrical output under windspeed variations are undesirable due to ...

  4. Impact of Wind Shear and Tower Shadow Effects on Power System with Large Scale Wind Power

    E-Print Network [OSTI]

    Hu, Weihao

    Impact of Wind Shear and Tower Shadow Effects on Power System with Large Scale Wind Power to wind speed variations, the wind shear and the tower shadow effects. The fluctuating power may be ableSILENT/PowerFactory. In this paper, the impacts of wind shear and tower shadow effects on the small signal stability of power systems

  5. Inverse Load Calculation of Wind Turbine Support Structures - A Numerical Verification Using the Comprehensive Simulation Code FAST: Preprint (Revised)

    SciTech Connect (OSTI)

    Pahn, T.; Jonkman, J.; Rolges, R.; Robertson, A.

    2012-11-01T23:59:59.000Z

    Physically measuring the dynamic responses of wind turbine support structures enables the calculation of the applied loads using an inverse procedure. In this process, inverse means deriving the inputs/forces from the outputs/responses. This paper presents results of a numerical verification of such an inverse load calculation. For this verification, the comprehensive simulation code FAST is used. FAST accounts for the coupled dynamics of wind inflow, aerodynamics, elasticity and turbine controls. Simulations are run using a 5-MW onshore wind turbine model with a tubular tower. Both the applied loads due to the instantaneous wind field and the resulting system responses are known from the simulations. Using the system responses as inputs to the inverse calculation, the applied loads are calculated, which in this case are the rotor thrust forces. These forces are compared to the rotor thrust forces known from the FAST simulations. The results of these comparisons are presented to assess the accuracy of the inverse calculation. To study the influences of turbine controls, load cases in normal operation between cut-in and rated wind speed, near rated wind speed and between rated and cut-out wind speed are chosen. The presented study shows that the inverse load calculation is capable of computing very good estimates of the rotor thrust. The accuracy of the inverse calculation does not depend on the control activity of the wind turbine.

  6. Performance of twist-coupled blades on variable speed rotors

    SciTech Connect (OSTI)

    Lobitz, D.W.; Veers, P.S.; Laino, D.J.

    1999-12-07T23:59:59.000Z

    The load mitigation and energy capture characteristics of twist-coupled HAWT blades that are mounted on a variable speed rotor are investigated in this paper. These blades are designed to twist toward feather as they bend with pretwist set to achieve a desirable twist distribution at rated power. For this investigation, the ADAMS-WT software has been modified to include blade models with bending-twist coupling. Using twist-coupled and uncoupled models, the ADAMS software is exercised for steady wind environments to generate C{sub p} curves at a number of operating speeds to compare the efficiencies of the two models. The ADAMS software is also used to generate the response of a twist-coupled variable speed rotor to a spectrum of stochastic wind time series. This spectrum contains time series with two mean wind speeds at two turbulence levels. Power control is achieved by imposing a reactive torque on the low speed shaft proportional to the RPM squared with the coefficient specified so that the rotor operates at peak efficiency in the linear aerodynamic range, and by limiting the maximum RPM to take advantage of the stall controlled nature of the rotor. Fatigue calculations are done for the generated load histories using a range of material exponents that represent materials from welded steel to aluminum to composites, and results are compared with the damage computed for the rotor without twist-coupling. Results indicate that significant reductions in damage are achieved across the spectrum of applied wind loading without any degradation in power production.

  7. Using satellite data for mapping offshore wind resources and wakes

    E-Print Network [OSTI]

    (no wind) Horns Rev Offshore Wind Farm Blaavandshuk Met. mast N #12;Wind Horns Rev Wind speed map from · Wake near large offshore wind farms is quantified in space and time · Software for usersUsing satellite data for mapping offshore wind resources and wakes Charlotte Bay Hasager, Merete

  8. Theoretical X-ray Line Profiles from Colliding Wind Binaries

    E-Print Network [OSTI]

    Henley, D B; Pittard, J M

    2003-01-01T23:59:59.000Z

    We present theoretical X-ray line profiles from a range of model colliding wind systems. In particular, we investigate the effects of varying the stellar mass-loss rates, the wind speeds, and the viewing orientation. We find that a wide range of theoretical line profile shapes is possible, varying with orbital inclination and phase. At or near conjunction, the lines have approximately Gaussian profiles, with small widths (HWHM ~ 0.1 v_infty) and definite blue- or redshifts (depending on whether the star with the weaker wind is in front or behind). When the system is viewed at quadrature, the lines are generally much broader (HWHM ~ v_infty), flat-topped and unshifted. Local absorption can have a major effect on the observed profiles - in systems with mass-loss rates of a few times 10^{-6} Msol/yr the lower energy lines (E wind of the primary. The orbital variation ...

  9. Analysis of the effects of integrating wind turbines into a conventional utility: a case study. Final report

    SciTech Connect (OSTI)

    Goldenblatt, M.K.; Wegley, H.L.; Miller, A.H.

    1982-08-01T23:59:59.000Z

    The impact on a utility incorporating wind turbine generation due to wind speed sampling frequency, wind turbine performance model, and wind speed forecasting accuracy is examined. The utility analyzed in the study was the Los Angeles Department of Water and Power and the wind turbine assumed was the MOD-2. The sensitivity of the economic value of wind turbine generation to wind speed sampling frequency and wind turbine modeling technique is examined as well as the impact of wind forecasting accuracy on utility operation and production costs. Wind speed data from San Gorgonio Pass, California during 1979 are used to estimate wind turbine performance using four different simulation methods. (LEW)

  10. Analysis of the effects of integrating wind turbines into a conventional utility: a case study. Revised final report

    SciTech Connect (OSTI)

    Goldenblatt, M.K.; Wegley, H.L.; Miller, A.H.

    1983-03-01T23:59:59.000Z

    The impact on a utility incorporating wind turbine generation due to wind speed sampling frequency, wind turbine performance model, and wind speed forecasting accuracy is examined. The utility analyzed in this study was the Los Angeles Department of Water and Power, and the wind turbine assumed was the MOD-2. The sensitivity of the economic value of wind turbine generation to wind speed sampling frequency and wind turbine modeling technique is examined as well as the impact of wind forecasting accuracy on utility operation and production costs. Wind speed data from San Gorgonio Pass, California during 1979 are used to estimate wind turbine performance using four different simulation methods. (LEW)

  11. Journal of Wind Engineering and Industrial Aerodynamics 90 (2002) 201221

    E-Print Network [OSTI]

    Pryor, Sara C.

    due largely to lower surface roughness [1]. An additional benefit to offshore location of wind farms characteristics in the near-shore and offshore environment using data from the Danish wind monitoring network. In this relatively high wind speed environment the temporal auto-correlation of wind speeds measured in the offshore

  12. Nonlinear Control of a Wind Turbine Sven Creutz Thomsen

    E-Print Network [OSTI]

    Nonlinear Control of a Wind Turbine Sven Creutz Thomsen Kongens Lyngby 2006 #12; Technical describes analysis of various nonlinear control methods for controlling a wind turbine. High speed wind Modeling and analysis 5 2 Model descriptions 7 2.1 Variable speed wind turbine

  13. Nonlinear Control of a Wind Turbine Sven Creutz Thomsen

    E-Print Network [OSTI]

    Nonlinear Control of a Wind Turbine Sven Creutz Thomsen Kongens Lyngby 2006 #12;Technical describes analysis of various nonlinear control methods for controlling a wind turbine. High speed wind descriptions 7 2.1 Variable speed wind turbine . . . . . . . . . . . . . . . . . . . . . . . . 8 2.2 Constant

  14. Use of synthetic aperture radar for offshore wind resource assessment and wind farm development in the UK 

    E-Print Network [OSTI]

    Cameron, Iain Dickson

    2008-01-01T23:59:59.000Z

    The UK has an abundant offshore wind resource with offshore wind farming set to grow rapidly over the coming years. Optimisation of energy production is of the utmost importance and accurate estimates of wind speed distributions are critical...

  15. The effects of energy storage properties and forecast accuracy on mitigating variability in wind power generation

    E-Print Network [OSTI]

    Jaworsky, Christina A

    2013-01-01T23:59:59.000Z

    Electricity generation from wind power is increasing worldwide. Wind power can offset traditional fossil fuel generators which is beneficial to the environment. However, wind generation is unpredictable. Wind speeds have ...

  16. Floating offshore wind farms : demand planning & logistical challenges of electricity generation

    E-Print Network [OSTI]

    Nnadili, Christopher Dozie, 1978-

    2009-01-01T23:59:59.000Z

    Floating offshore wind farms are likely to become the next paradigm in electricity generation from wind energy mainly because of the near constant high wind speeds in an offshore environment as opposed to the erratic wind ...

  17. New Concepts in Wind Power Forecasting Models

    E-Print Network [OSTI]

    Kemner, Ken

    New Concepts in Wind Power Forecasting Models Vladimiro Miranda, Ricardo Bessa, João Gama, Guenter to the training of mappers such as neural networks to perform wind power prediction as a function of wind characteristics (mainly speed and direction) in wind parks connected to a power grid. Renyi's Entropy is combined

  18. Wind information derived from hot air

    E-Print Network [OSTI]

    Haak, Hein

    Wind information derived from hot air balloon flights for use in short term wind forecasts E Introduction/Motivation Hot air balloons as wind measuring device Setup of nested HIRLAM models Results · Three, The Nertherlands #12;Hot air balloon ·Displacement/time unit = wind speed ·Vertical resolution 30m ·Inertia (500 kg

  19. Wind farm electrical system

    DOE Patents [OSTI]

    Erdman, William L.; Lettenmaier, Terry M.

    2006-07-04T23:59:59.000Z

    An approach to wind farm design using variable speed wind turbines with low pulse number electrical output. The output of multiple wind turbines are aggregated to create a high pulse number electrical output at a point of common coupling with a utility grid network. Power quality at each individual wind turbine falls short of utility standards, but the aggregated output at the point of common coupling is within acceptable tolerances for utility power quality. The approach for aggregating low pulse number electrical output from multiple wind turbines relies upon a pad mounted transformer at each wind turbine that performs phase multiplication on the output of each wind turbine. Phase multiplication converts a modified square wave from the wind turbine into a 6 pulse output. Phase shifting of the 6 pulse output from each wind turbine allows the aggregated output of multiple wind turbines to be a 24 pulse approximation of a sine wave. Additional filtering and VAR control is embedded within the wind farm to take advantage of the wind farm's electrical impedence characteristics to further enhance power quality at the point of common coupling.

  20. ANALYSIS OF THE PERFORMANCE AND COST EFFECTIVENESS OF NINE SMALL WIND ENERGY CONVERSION SYSTEMS FUNDED BY THE DOE SMALL GRANTS PROGRAM

    E-Print Network [OSTI]

    Kay, J.

    2009-01-01T23:59:59.000Z

    relationship between potential wind speed and theoreticalfirm contracts. Potential wind investors face considerable15 with optimism the potential that wind, photovoltaic, and

  1. Doubly Fed Induction Generator in an Offshore Wind Power Plant Operated at Rated V/Hz: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Singh, M.; Gevorgian, V.

    2012-06-01T23:59:59.000Z

    This paper introduces the concept of constant Volt/Hz operation of offshore wind power plants. The deployment of offshore WPPs requires power transmission from the plant to the load center inland. Since this power transmission requires submarine cables, there is a need to use High-Voltage Direct Current transmission, which is economical for transmission distances longer than 50 kilometers. In the concept presented here, the onshore substation is operated at 60 Hz synced with the grid, and the offshore substation is operated at variable frequency and voltage, thus allowing the WPP to be operated at constant Volt/Hz.

  2. Abstract--Wind power generation is growing rapidly. However, maintaining the wind turbine connection to grid is a real

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    by the year 2020 [2]. Wind turbines can operate either with a fixed speed or a variable speed. In the case and then as fluctuations in the electrical power on the grid. The variable-speed turbine operation offers several major acoustical [3]. Among variable speed constant-frequency wind turbines, the doubly fed induction generator

  3. Modelling Tools for Wind Farm Upgrading Hans Georg Beyer*, Bernhard Lange, Hans-Peter Waldl

    E-Print Network [OSTI]

    Heinemann, Detlev

    rows (see Figure 1). They are pitch controlled variable speed turbines with a rated power of 330 kW (WT-Antipolis, France ABSTRACT: Planning of modifications of existing wind farms by adding or replacing turbines makes of the farm to that of individual turbines. Additionally, modelling has to deal with different turbine types

  4. Comparison of model and observations of the wake of a MOD-OA wind turbine

    SciTech Connect (OSTI)

    Doran, J.C.; Packard, K.R.

    1982-10-01T23:59:59.000Z

    A series of wind velocity measurements upwind and downwind of the MOD-OA wind turbine at Clayton, New Mexico, was used to determine some of the characteristics of wakes within approximately two blade diameters of the machine. The magnitudes and shapes of the velocity profiles downwind of the turbine were compared with results obtained from a model. Generally good agreement was obtained at speeds well below the rated speed of the MOD-OA, but the results were not as satisfactory for higher values.

  5. Distributed Wind Energy in Idaho

    SciTech Connect (OSTI)

    Gardner, John; Ferguson, James; Ahmed-Zaid, Said; Johnson, Kathryn; Haynes, Todd; Bennett, Keith

    2009-01-31T23:59:59.000Z

    Project Objective: This project is a research and development program aimed at furthering distributed wind technology. In particular, this project addresses some of the barriers to distributed wind energy utilization in Idaho. Background: At its core, the technological challenge inherent in Wind Energy is the transformation of a highly variable form of energy to one which is compatible with the commercial power grid or another useful application. A major economic barrier to the success of distributed wind technology is the relatively high capital investment (and related long payback periods) associated with wind turbines. This project will carry out fundamental research and technology development to address both the technological and economic barriers. � Active drive train control holds the potential to improve the overall efficiency of a turbine system by allowing variable speed turbine operation while ensuring a tight control of generator shaft speed, thus greatly simplifying power conditioning. � Recent blade aerodynamic advancements have been focused on large, utility-scale wind turbine generators (WTGs) as opposed to smaller WTGs designed for distributed generation. Because of Reynolds Number considerations, blade designs do not scale well. Blades which are aerodynamically optimized for distributed-scale WTGs can potentially reduce the cost of electricity by increasing shaft-torque in a given wind speed. � Grid-connected electric generators typically operate at a fixed speed. If a generator were able to economically operate at multiple speeds, it could potentially convert more of the wind�s energy to electricity, thus reducing the cost of electricity. This research directly supports the stated goal of the Wind and Hydropower Technologies Program for Distributed Wind Energy Technology: By 2007, reduce the cost of electricity from distributed wind systems to 10 to 15 cents/kWh in Class 3 wind resources, the same level that is currently achievable in Class 5 winds.

  6. Minimizing Variation in Outdoor CPV Power Ratings: Preprint

    SciTech Connect (OSTI)

    Muller, M.; Marion, B.; Rodriguez, J.; Kurtz, S.

    2011-07-01T23:59:59.000Z

    The CPV community has agreed to have both indoor and outdoor power ratings at the module level. The indoor rating provides a repeatable measure of module performance as it leaves the factory line while the outdoor rating provides a measure of true performance under real world conditions. The challenge with an outdoor rating is that the spectrum, temperature, wind speed, etc are constantly in flux and therefore the resulting power rating varies from day to day and month to month. This work examines different methodologies for determining the outdoor power rating with the goal of minimizing variation even if data are collected under changing meteorological conditions.

  7. Wind climatology of Schiphol Andrew Stepek, Xueli Wang and Dirk Wolters

    E-Print Network [OSTI]

    Haak, Hein

    Wind climatology of Schiphol Andrew Stepek, Xueli Wang and Dirk Wolters De Bilt, May 2012 #12;2 Contents Summary 2 Introduction 3 Data 3 Hourly wind measurements 3 Yearly averages of wind speed measurements 4 Quality and sources of error 6 Method 7 Trends in wind speed 7 Definition of cross and tail wind

  8. Is the Weibull distribution really suited for wind statistics modeling and wind power evaluation?

    E-Print Network [OSTI]

    Drobinski, Philippe

    2012-01-01T23:59:59.000Z

    Wind speed statistics is generally modeled using the Weibull distribution. This distribution is convenient since it fully characterizes analytically with only two parameters (the shape and scale parameters) the shape of distribution and the different moments of the wind speed (mean, standard deviation, skewness and kurtosis). This distribution is broadly used in the wind energy sector to produce maps of wind energy potential. However, the Weibull distribution is based on empirical rather than physical justification and might display strong limitations for its applications. The philosophy of this article is based on the modeling of the wind components instead of the wind speed itself. This provides more physical insights on the validity domain of the Weibull distribution as a possible relevant model for wind statistics and the quantification of the error made by using such a distribution. We thereby propose alternative expressions of more suited wind speed distribution.

  9. MSU-Wind Applications Center: Wind Resource Worksheet Theoretical Power Calculation

    E-Print Network [OSTI]

    Dyer, Bill

    MSU-Wind Applications Center: Wind Resource Worksheet Theoretical Power Calculation Equations: A= swept area = air density v= velocity R= universal gas constant Steps: 1. Measure wind speed from fan. = ___________/(________*________)= _________kg/m3 5. Theoretical Power a. Low Setting Theoretical Wind Power i. Power= ½*______*______*______*.59

  10. PSO (FU 2101) Ensemble-forecasts for wind power

    E-Print Network [OSTI]

    PSO (FU 2101) Ensemble-forecasts for wind power Wind Power Ensemble Forecasting Using Wind Speed the problems of (i) transforming the meteorological ensembles to wind power ensembles and, (ii) correcting) data. However, quite often the actual wind power production is outside the range of ensemble forecast

  11. Active control system for high speed windmills

    DOE Patents [OSTI]

    Avery, D.E.

    1988-01-12T23:59:59.000Z

    A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed. 4 figs.

  12. Active control system for high speed windmills

    DOE Patents [OSTI]

    Avery, Don E. (45-437 Akimala St., Honolulu, HI 96744)

    1988-01-01T23:59:59.000Z

    A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed.

  13. Wind Fields over the Great Lakes Measured by the SeaWinds Scatterometer on the QuikSCAT Satellite

    E-Print Network [OSTI]

    Wind Fields over the Great Lakes Measured by the SeaWinds Scatterometer on the QuikSCAT Satellite for wind retrieval over the Great Lakes on a daily basis. We use data acquired by the SeaWinds Scatterometer on the QuikSCAT (QSCAT) satellite launched in June 1999 to derive wind speeds and directions over

  14. Wind Energy Permitting Standards (North Carolina)

    Broader source: Energy.gov [DOE]

    North Carolina has statewide permitting requirements for wind energy facilities. Any wind turbine or collection of wind turbines located within a half mile of each other with a collective rated...

  15. Numeric-modeling sensitivity analysis of the performance of wind turbine arrays

    SciTech Connect (OSTI)

    Lissaman, P.B.S.; Gyatt, G.W.; Zalay, A.D.

    1982-06-01T23:59:59.000Z

    An evaluation of the numerical model created by Lissaman for predicting the performance of wind turbine arrays has been made. Model predictions of the wake parameters have been compared with both full-scale and wind tunnel measurements. Only limited, full-scale data were available, while wind tunnel studies showed difficulties in representing real meteorological conditions. Nevertheless, several modifications and additions have been made to the model using both theoretical and empirical techniques and the new model shows good correlation with experiment. The larger wake growth rate and shorter near wake length predicted by the new model lead to reduced interference effects on downstream turbines and hence greater array efficiencies. The array model has also been re-examined and now incorporates the ability to show the effects of real meteorological conditions such as variations in wind speed and unsteady winds. The resulting computer code has been run to show the sensitivity of array performance to meteorological, machine, and array parameters. Ambient turbulence and windwise spacing are shown to dominate, while hub height ratio is seen to be relatively unimportant. Finally, a detailed analysis of the Goodnoe Hills wind farm in Washington has been made to show how power output can be expected to vary with ambient turbulence, wind speed, and wind direction.

  16. Collegiate Wind Competition Turbines go Blade-to-Blade in Wind...

    Energy Savers [EERE]

    by university teams, these wind turbines will compete in areas such as performance, power control, and safety ratings. Prototypes of the wind turbines will be tested in a...

  17. Observed and CAM3 GCM Sea Surface Wind

    E-Print Network [OSTI]

    Zender, Charles

    Observed and CAM3 GCM Sea Surface Wind Speed Distributions: Characterization, Comparison, and Bias climatological surface wind speed probability density functions (PDFs) estimated from observations and use them to evaluate, for the first time, contemporaneous wind PDFs predicted by a GCM. The ob- servations include NASA

  18. Wind velocity measurements using a pulsed LIDAR system: first results

    E-Print Network [OSTI]

    Peinke, Joachim

    . A laser beam of 1.54 µm wavelength takes measurements of the wind speed in beamwise direction. To obtain the three-dimensinal wind vector, the beam is inclined by 30 from vertical direction and measurements 12345 t [s] vh[m/s] Figure 2. Segment of measured time series of the horizontal wind speed magnitude vh

  19. Analyzing the Effects of Temporal Wind Patterns on the Value of Wind-Generated Electricity at Different Sites in California and the Northwest

    E-Print Network [OSTI]

    Fripp, Matthias; Wiser, Ryan

    2006-01-01T23:59:59.000Z

    7 2.2.3 Wind Farm Production1. Rated Capacity of Wind Farms for which Monthly Productionpower from potential wind farm locations in California and

  20. Analysis of Wind Power Generation of Texas

    E-Print Network [OSTI]

    Liu, Z.; Haberl, J.; Subbarao, K.; Baltazar, J. C.

    from Jul 2002 to Jan 2003 Degradation Analysis - On average, no degradation observed for nine wind farms analyzed over 4-year period. Application of Method 1 to New Site- Sweetwater I Wind Farm ? Energy Systems Laboratory, Texas A&M University Page 3...&M University Page 10 Weather Data: NOAA- ABI 1999 and 2005 Hourly Wind Speed NOAA -ABI Hourly Wind Speed -1999 0 10 20 30 40 Jan-99 Feb-99 M ar-99 Apr-99 M ay-99 Jun-99 Jul-99 Aug-99 Sep-99 Oct-99 Nov-99 Dec-99 W in d Spe ed [m ph ] NOAA -ABI Hourly Wind...

  1. Offshore wind resource assessment through satellite images

    E-Print Network [OSTI]

    1 Slide no. 4 Offshore wind resource assessment through satellite images Charlotte Bay Hasager images for offshore wind ressource assessment in lieu of in-situ mast observations #12;4 Slide no Hasager, Dellwik, Nielsen and Furevik, 2004, Validation of ERS-2 SAR offshore wind-speed maps in the North

  2. UNIVERSITY of CALIFORNIA INVESTIGATION OF HOW ANGLE OF ATTACK AFFECTS ROTOR SPEED

    E-Print Network [OSTI]

    Belanger, David P.

    -pitch blades is tested in UCSC's wind tunnel. The turbine is used to test how varying the blade angle affects the turbine's rotational speed at different wind speeds. The data are used to determine how the blade angle 27 Appendix A Wind Turbine Data 29 Appendix B Converting Blade Pitch to Needle Angle 33 Appendix C

  3. WIND ENERGY Wind Energ. (2014)

    E-Print Network [OSTI]

    Peinke, Joachim

    2014-01-01T23:59:59.000Z

    loads from the wind inflow through rotor aerodynamics, drive train and power electronics is stillWIND ENERGY Wind Energ. (2014) Published online in Wiley Online Library (wileyonlinelibrary wind inflow conditions M. R. Luhur, J. Peinke, J. Schneemann and M. Wächter ForWind-Center for Wind

  4. High Wind Penetration Impact on U.S. Wind Manufacturing Capacity and Critical Resources

    SciTech Connect (OSTI)

    Laxson, A.; Hand, M. M.; Blair, N.

    2006-10-01T23:59:59.000Z

    This study used two different models to analyze a number of alternative scenarios of annual wind power capacity expansion to better understand the impacts of high levels of wind generated electricity production on wind energy manufacturing and installation rates.

  5. OPERATIONAL TEST OF SONIC WIND SENSORS AT KNMI Wiel M.F. Wauben

    E-Print Network [OSTI]

    Wauben, Wiel

    of transfer functions for wind direction, - speed and - gust that account for the change from one sensor vanes to measure wind speed and direction. Although the KNMI cup and vane meet WMO requirements into account by a wind direction and - speed dependent correction that is applied in the sensor software

  6. Dust Detection by the Wave Instrument on STEREO: Nanoparticles Picked up by the Solar Wind?

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    2007, Basics of the Solar Wind, Cambridge University Press,Picked up by the Solar Wind? N. Meyer-Vernet · M. Maksimovicof magnitude of the solar wind speed. Nanoparticles, which

  7. Ris-R-1182(EN) Equalizing Effects of the Wind Energy

    E-Print Network [OSTI]

    Risø-R-1182(EN) Equalizing Effects of the Wind Energy Production in Northern Europe Determined from in time were used. The methodology to get a common wind energy production from reanalysis wind speeds

  8. Coastal Ohio Wind Project for Reduced Barriers to Deployment of Offshore Wind Energy

    SciTech Connect (OSTI)

    Gorsevski, Peter; Afjeh, Abdollah; Jamali, Mohsin; Carroll, Michael

    2014-04-09T23:59:59.000Z

    The Coastal Ohio Wind Project was created to establish the viability of wind turbines on the coastal and offshore regions of Northern Ohio. The project’s main goal was to improve operational unit strategies used for environmental impact assessment of offshore turbines on lake wildlife by optimizing and fusing data from the multi-instrument surveillance system and providing an engineering analysis of potential design/operational alternatives for offshore wind turbines. The project also developed a general economic model for offshore WTG deployment to quantify potential revenue losses due to wind turbine shutdown related to ice and avian issues. In a previous phase of this project (Award Number: DE-FG36-06GO86096), we developed a surveillance system that was used to collect different parameters such as passage rates, flight paths, flight directions, and flight altitudes of nocturnal migrating species, movements of birds and bats, and bird calls for assessing patterns and peak passage rates during migration. To derive such parameters we used thermal IR imaging cameras, acoustic recorders, and marine radar Furuno (XANK250), which was coupled with a XIR3000B digitizing card from Russell Technologies and open source radR processing software. The integration yielded a development of different computational techniques and methods, which we further developed and optimized as a combined surveillance system. To accomplish this task we implemented marine radar calibration, optimization of processing parameters, and fusion of the multi-sensor data in order to make inferences about the potential avian targets. The main goal of the data fusion from the multi-sensor environment was aimed at reduction of uncertainties while providing acceptable confidence levels with detailed information about the migration patterns. Another component comprised of an assessment of wind resources in a near lake environment and an investigation of the effectiveness of ice coating materials to mitigate adverse effects of ice formation on wind turbine structures. Firstly, a Zephir LiDAR system was acquired and installed at Woodlands School in Huron, Ohio, which is located near Lake Erie. Wind resource data were obtained at ten measurement heights, 200m, 150m, 100m, 80m, 60m, 40m, 38m, 30m, 20m, and 10m. The Woodlands School’s wind turbine anemometer also measured the wind speed at the hub height. These data were collected for approximately one year. The hub anemometer data correlated well with the LiDAR wind speed measurements at the same height. The data also showed that on several days different power levels were recorded by the turbine at the same wind speed as indicated by the hub anemometer. The corresponding LiDAR data showed that this difference can be attributed to variability in the wind over the turbine rotor swept area, which the hub anemometer could not detect. The observation suggests that single point hub wind velocity measurements are inadequate to accurately estimate the power generated by a turbine at all times since the hub wind speed is not a good indicator of the wind speed over the turbine rotor swept area when winds are changing rapidly. To assess the effectiveness of ice coatings to mitigate the impact of ice on turbine structures, a closed-loop icing research tunnel (IRT) was designed and constructed. By controlling the temperature, air speed, water content and liquid droplet size, the tunnel enabled consistent and repeatable ice accretion under a variety of conditions with temperatures between approximately 0°C and -20°C and wind speeds up to 40 miles per hour in the tunnel’s test section. The tunnel’s cooling unit maintained the tunnel temperature within ±0.2°C. The coatings evaluated in the study were Boyd Coatings Research Company’s CRC6040R3, MicroPhase Coatings Inc.’s PhaseBreak TP, ESL and Flex coatings. Similar overall performance was observed in all coatings tested in that water droplets form on the test articles beginning at the stagnation region and spreading in the downstream direction in time. When compari

  9. Robust model based control method for wind energy production A. Pintea 1

    E-Print Network [OSTI]

    Boyer, Edmond

    - linear form on the wind speed, the rotation speed of the turbine and the pitch angle of the blades based control algorithm for a horizontal wind turbine is proposed. In a model-based control approach system. Keywords: Wind power, robustness, IMC, stability, turbine, pitch control. 1. INTRODUCTION Wind

  10. Pitfalls of modeling wind power using Markov chains

    E-Print Network [OSTI]

    Kirtley, James L., Jr.

    An increased penetration of wind turbines have given rise to a need for wind speed/power models that generate realistic synthetic data. Such data, for example, might be used in simulations to size energy storage or spinning ...

  11. air gap windings: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    produced vs NOAA wind data. Issue: too much scatter. Hourly Turbine Power vs. Wind Speed (On-site) 0 10 20 30... Haberl, J.; Yazdani, B.; Culp, C. 40 AIR-SEA INTERACTIONS FROM...

  12. Wind Power Plant Prediction by Using Neural Networks: Preprint

    SciTech Connect (OSTI)

    Liu, Z.; Gao, W.; Wan, Y. H.; Muljadi, E.

    2012-08-01T23:59:59.000Z

    This paper introduces a method of short-term wind power prediction for a wind power plant by training neural networks based on historical data of wind speed and wind direction. The model proposed is shown to achieve a high accuracy with respect to the measured data.

  13. Wind resource assessment with a mesoscale non-hydrostatic model

    E-Print Network [OSTI]

    Boyer, Edmond

    Wind resource assessment with a mesoscale non- hydrostatic model Vincent Guénard, Center for Energy is developed for assessing the wind resource and its uncertainty. The work focuses on an existing wind farm mast measurements. The wind speed and turbulence fields are discussed. It is shown that the k

  14. Dynamic Simulation of DFIG Wind Turbines on FPGA Boards

    E-Print Network [OSTI]

    Zambreno, Joseph A.

    Dynamic Simulation of DFIG Wind Turbines on FPGA Boards Hao Chen, Student Member, IEEE, Song Sun is a friction coefficient. The wind turbine model is based on the relation between the upstream wind speed V w + 1 where p is the air density; Rw is the wind turbine radius; cp (A, (3) is the performance

  15. Ris National Laboratory Satellite SAR applied in offshore wind

    E-Print Network [OSTI]

    Risø National Laboratory Satellite SAR applied in offshore wind ressource mapping: possibilities is to quantify the regional offshore wind climate for wind energy application based on satellite SAR ·Study of 85SAR(m/s) Hasager, Dellwik, Nielsen and Furevik, 2004, Validation of ERS-2 SAR offshore wind-speed maps

  16. RisR1238(EN) Extreme Winds over Denmark

    E-Print Network [OSTI]

    Risø­R­1238(EN) Extreme Winds over Denmark from the NCEP/NCAR Reanalysis Helmut P. Frank Wind Energy Department Risø National Laboratory Roskilde, Denmark E-mail: helmut.frank@risoe.dk Risø National Laboratory, Roskilde, Denmark May 2001 #12;Abstract An extreme wind analysis of wind speed calculated

  17. South Carolina Opens Nation's Largest Wind Drivetrain Testing...

    Broader source: Energy.gov (indexed) [DOE]

    the facility will help test and validate new turbines, particularly for offshore wind-helping to speed deployment of next generation energy technology, reduce costs for...

  18. South Carolina Opens Nation's Largest Wind Drivetrain Testing...

    Broader source: Energy.gov (indexed) [DOE]

    The facility will help test and validate new turbines, particularly for offshore wind- helping to speed deployment of next generation energy technology, reduce costs for...

  19. average wind shear: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    by uncompensated voids. Maria Mattsson; Teppo Mattsson 2010-07-17 7 Probabilistic Wind Speed Forecasting using Ensembles and Bayesian Model Averaging Mathematics Websites Summary:...

  20. Sensitivity Analysis of Offshore Wind Cost of Energy (Poster)

    SciTech Connect (OSTI)

    Dykes, K.; Ning, A.; Graf, P.; Scott, G.; Damiami, R.; Hand, M.; Meadows, R.; Musial, W.; Moriarty, P.; Veers, P.

    2012-10-01T23:59:59.000Z

    No matter the source, offshore wind energy plant cost estimates are significantly higher than for land-based projects. For instance, a National Renewable Energy Laboratory (NREL) review on the 2010 cost of wind energy found baseline cost estimates for onshore wind energy systems to be 71 dollars per megawatt-hour ($/MWh), versus 225 $/MWh for offshore systems. There are many ways that innovation can be used to reduce the high costs of offshore wind energy. However, the use of such innovation impacts the cost of energy because of the highly coupled nature of the system. For example, the deployment of multimegawatt turbines can reduce the number of turbines, thereby reducing the operation and maintenance (O&M) costs associated with vessel acquisition and use. On the other hand, larger turbines may require more specialized vessels and infrastructure to perform the same operations, which could result in higher costs. To better understand the full impact of a design decision on offshore wind energy system performance and cost, a system analysis approach is needed. In 2011-2012, NREL began development of a wind energy systems engineering software tool to support offshore wind energy system analysis. The tool combines engineering and cost models to represent an entire offshore wind energy plant and to perform system cost sensitivity analysis and optimization. Initial results were collected by applying the tool to conduct a sensitivity analysis on a baseline offshore wind energy system using 5-MW and 6-MW NREL reference turbines. Results included information on rotor diameter, hub height, power rating, and maximum allowable tip speeds.

  1. Effects of Temporal Wind Patterns on the Value of Wind-Generated Electricity in California and the Northwest

    E-Print Network [OSTI]

    Wiser, Ryan H

    2008-01-01T23:59:59.000Z

    value of re- newable electricity; and customer surveys ofCalifornia or Northwestern electricity demand. This may bebetween wind speed and electricity demand," Solar Energy,

  2. Line formation in the inner winds of classical T Tauri stars: testing the conical wind solution

    E-Print Network [OSTI]

    Kurosawa, Ryuichi

    2012-01-01T23:59:59.000Z

    We present the emission line profile models of hydrogen and helium based on the results from axisymmetric magnetohydrodynamics (MHD) simulations of the wind formed near the disk-magnetosphere boundary of classical T Tauri stars (CTTSs). We extend the previous outflow models of `the conical wind' by Romanova et al. to include a well defined magnetospheric accretion funnel flow which is essential for modelling the optical and near-infrared hydrogen and helium lines of CTTSs. Our MHD model shows outflows in conical shape with a half opening angle about 35 degrees. The flow properties such as the maximum outflow speed in the conical wind, maximum inflow speed in the accretion funnel, mass-accretion and mass-loss rates are comparable to those found in a typical CTTS. The density, velocity and temperature from the MHD simulations are used in a separate radiative transfer model to predict the line profiles and test the consistency of the MHD models with observations. The line profiles are computed with various combi...

  3. Review of Wind Energy Forecasting Methods for Modeling Ramping Events

    SciTech Connect (OSTI)

    Wharton, S; Lundquist, J K; Marjanovic, N; Williams, J L; Rhodes, M; Chow, T K; Maxwell, R

    2011-03-28T23:59:59.000Z

    Tall onshore wind turbines, with hub heights between 80 m and 100 m, can extract large amounts of energy from the atmosphere since they generally encounter higher wind speeds, but they face challenges given the complexity of boundary layer flows. This complexity of the lowest layers of the atmosphere, where wind turbines reside, has made conventional modeling efforts less than ideal. To meet the nation's goal of increasing wind power into the U.S. electrical grid, the accuracy of wind power forecasts must be improved. In this report, the Lawrence Livermore National Laboratory, in collaboration with the University of Colorado at Boulder, University of California at Berkeley, and Colorado School of Mines, evaluates innovative approaches to forecasting sudden changes in wind speed or 'ramping events' at an onshore, multimegawatt wind farm. The forecast simulations are compared to observations of wind speed and direction from tall meteorological towers and a remote-sensing Sound Detection and Ranging (SODAR) instrument. Ramping events, i.e., sudden increases or decreases in wind speed and hence, power generated by a turbine, are especially problematic for wind farm operators. Sudden changes in wind speed or direction can lead to large power generation differences across a wind farm and are very difficult to predict with current forecasting tools. Here, we quantify the ability of three models, mesoscale WRF, WRF-LES, and PF.WRF, which vary in sophistication and required user expertise, to predict three ramping events at a North American wind farm.

  4. Commonwealth Wind Commercial Wind Program

    Broader source: Energy.gov [DOE]

    Through the Commonwealth Wind Incentive Program – Commercial Wind Initiative the Massachusetts Clean Energy Center (MassCEC) offers site assessment grants of services, feasibility study grants, a...

  5. Co-existence of whistler waves with kinetic Alfven wave turbulence for the high-beta solar wind plasma

    SciTech Connect (OSTI)

    Mithaiwala, Manish; Crabtree, Chris; Ganguli, Gurudas [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375-5346 (United States); Rudakov, Leonid [Icarus Research Inc., P.O. Box 30780, Bethesda, Maryland 20824-0780 (United States)

    2012-10-15T23:59:59.000Z

    It is shown that the dispersion relation for whistler waves is identical for a high or low beta plasma. Furthermore, in the high-beta solar wind plasma, whistler waves meet the Landau resonance with electrons for velocities less than the thermal speed, and consequently, the electric force is small compared to the mirror force. As whistlers propagate through the inhomogeneous solar wind, the perpendicular wave number increases through refraction, increasing the Landau damping rate. However, the whistlers can survive because the background kinetic Alfven wave (KAW) turbulence creates a plateau by quasilinear (QL) diffusion in the solar wind electron distribution at small velocities. It is found that for whistler energy density of only {approx}10{sup -3} that of the kinetic Alfven waves, the quasilinear diffusion rate due to whistlers is comparable to KAW. Thus, very small amplitude whistler turbulence can have a significant consequence on the evolution of the solar wind electron distribution function.

  6. The dominant X-ray wind in massive star binaries

    E-Print Network [OSTI]

    J. M. Pittard; I. R. Stevens

    2002-04-15T23:59:59.000Z

    We investigate which shocked wind is responsible for the majority of the X-ray emission in colliding wind binaries, an issue where there is some confusion in the literature, and which we show is more complicated than has been assumed. We find that where both winds rapidly cool (typically close binaries), the ratio of the wind speeds is often more important than the momentum ratio, because it controls the energy flux ratio, and the faster wind is generally the dominant emitter. When both winds are largely adiabatic (typically long-period binaries), the slower and denser wind will cool faster and the stronger wind generally dominates the X-ray luminosity.

  7. air speed indicators: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A; Rozelot, J P; 10.10880004-637X727144 2011-01-01 6 High speed air pneumatic wind shield wiping design MIT - DSpace Summary: In this creative design process a number of...

  8. Abstract--This paper addresses the problem of controlling wind energy conversion systems (WECS) which involve

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Abstract-- This paper addresses the problem of controlling wind energy conversion systems (WECS-inverter. The goal of control is to maximize wind energy extraction and this needs letting the wind turbine rotor wind energy extraction) only for one wind speed value depending on the considered value of turbine

  9. Prediction, operations, and condition monitoring in wind energy Andrew Kusiak a,*, Zijun Zhang b

    E-Print Network [OSTI]

    Kusiak, Andrew

    Review Prediction, operations, and condition monitoring in wind energy Andrew Kusiak a,*, Zijun 2013 Available online 23 August 2013 Keywords: Wind energy Wind speed prediction Wind turbine control Condition monitoring and fault detection a b s t r a c t Recent developments in wind energy research

  10. Systems Performance Analyses of Alaska Wind-Diesel Projects; Kotzebue, Alaska (Fact Sheet)

    SciTech Connect (OSTI)

    Baring-Gould, I.

    2009-04-01T23:59:59.000Z

    This fact sheet summarizes a systems performance analysis of the wind-diesel project in Kotzebue, Alaska. Data provided for this project include wind turbine output, average wind speed, average net capacity factor, and optimal net capacity factor based on Alaska Energy Authority wind data, estimated fuel savings, and wind system availability.

  11. Impact of DFIG wind turbines on transient stability of power systems a review

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    Impact of DFIG wind turbines on transient stability of power systems ­ a review Authors Na Abstract of wind farms are using variable speed wind turbines equipped with doubly-fed induction generators (DFIG) due to their advantages over other wind turbine generators. Therefore, the analysis of wind power

  12. Time-domain Fatigue Response and Reliability Analysis of Offshore Wind Turbines with

    E-Print Network [OSTI]

    Nørvåg, Kjetil

    Time-domain Fatigue Response and Reliability Analysis of Offshore Wind Turbines with Emphasis of offshore wind turbines Defense: 09.12.2012 2012 - : Structural Engineer in Det Norske Veritas (DNV) 2007 and higher wind speed, and less visual disturbance and noise for offshore wind energy. Offshore wind

  13. Application of the AC Commutator Machine in Wind Energy Conversion Systems

    E-Print Network [OSTI]

    El-Jamous, Sami Georges

    1981-01-01T23:59:59.000Z

    OF C~ Page ABSTRACT DEDICATION iV LIST OF TABLES LIST OF FIGURES A SURVEY OF THE LITJRATURE Constant Speed Constant Frequency Systems (CSCF) Variable Speed Constant Frequency Systems (VSCF) BASIC THEORY OF WIND TURBINES Classification...] 57 59 61 21. Power, P snd torque, T /rotational speed curves for P P different wind speeds [1] 63 22. Torque-speed curves of the turbine for different wind speeds V 23. Torque-speed curves with shunt ACCG 24. Connection of the shunt ACCG...

  14. WIND ENERGY Wind Energ. (2014)

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    in the near wake. In conclusion, WiTTS performs satisfactorily in the rotor region of wind turbine wakes under neutral stability. Copyright © 2014 John Wiley & Sons, Ltd. KEYWORDS wind turbine wake; wake model; self in wind farms along several rows and columns. Because wind turbines generate wakes that propagate downwind

  15. Subhourly wind forecasting techniques for wind turbine operations

    SciTech Connect (OSTI)

    Wegley, H.L.; Kosorok, M.R.; Formica, W.J.

    1984-08-01T23:59:59.000Z

    Three models for making automated forecasts of subhourly wind and wind power fluctuations were examined to determine the models' appropriateness, accuracy, and reliability in wind forecasting for wind turbine operation. Such automated forecasts appear to have value not only in wind turbine control and operating strategies, but also in improving individual wind turbine control and operating strategies, but also in improving individual wind turbine operating strategies (such as determining when to attempt startup). A simple persistence model, an autoregressive model, and a generalized equivalent Markhov (GEM) model were developed and tested using spring season data from the WKY television tower located near Oklahoma City, Oklahoma. The three models represent a pure measurement approach, a pure statistical method and a statistical-dynamical model, respectively. Forecasting models of wind speed means and measures of deviations about the mean were developed and tested for all three forecasting techniques for the 45-meter level and for the 10-, 30- and 60-minute time intervals. The results of this exploratory study indicate that a persistence-based approach, using onsite measurements, will probably be superior in the 10-minute time frame. The GEM model appears to have the most potential in 30-minute and longer time frames, particularly when forecasting wind speed fluctuations. However, several improvements to the GEM model are suggested. In comparison to the other models, the autoregressive model performed poorly at all time frames; but, it is recommended that this model be upgraded to an autoregressive moving average (ARMA or ARIMA) model. The primary constraint in adapting the forecasting models to the production of wind turbine cluster power output forecasts is the lack of either actual data, or suitable models, for simulating wind turbine cluster performance.

  16. The solar wind in the outer heliosphere

    E-Print Network [OSTI]

    Richardson, John D.

    The solar wind evolves as it moves outward due to interactions with both itself and with the circum-heliospheric interstellar medium. The speed is, on average, constant out to 30 AU, then starts a slow decrease due to the ...

  17. Wind extremes in the North Sea Basin under climate change: An ensemble study of 12 CMIP5 GCMs

    E-Print Network [OSTI]

    Haak, Hein

    Wind extremes in the North Sea Basin under climate change: An ensemble study of 12 CMIP5 GCMs R. C levels and waves are generated by low atmospheric pressure and severe wind speeds during storm events. As a result of the geometry of the North Sea, not only the maximum wind speed is relevant, but also wind

  18. Forest impact estimated with NOAA AVHRR and Landsat TM data related to an empirical hurricane wind-field distribution

    E-Print Network [OSTI]

    Hodgson, Michael E.

    with Hurricane Andrew in 1992. The wind-field model projected that the highest wind speeds were in the southernForest impact estimated with NOAA AVHRR and Landsat TM data related to an empirical hurricane wind to relate forest type and hurricane-impact distribution with wind speed and duration to explain

  19. WindTurbineGenerator Introduction of the Renewable Micro-Grid Test-Bed

    E-Print Network [OSTI]

    Johnson, Eric E.

    Simulator Wind Turbine: PMSM, 3kW, 8.3A Wind Generator: PMSM, 3kW, 8.3A 3 AC/DC Converter & DC/AC Inverter Wind Turbine: Torque or Speed Control Wind Generator: PQ Control Cubicle #4: Energy Storage Generator #1 3kW, 8.3A Wind Turbine #1 3kW, 8.3A Wind Turbine #2 3kW Wind Generator #2 3kW RS232

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

    SciTech Connect (OSTI)

    Huskey, A.

    2011-11-01T23:59:59.000Z

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

  1. Understanding Inertial and Frequency Response of Wind Power Plants: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Gevorgian, V.; Singh, M.; Santoso, S.

    2012-07-01T23:59:59.000Z

    The objective of this paper is to analyze and quantify the inertia and frequency responses of wind power plants with different wind turbine technologies (particularly those of fixed speed, variable slip with rotor-resistance controls, and variable speed with vector controls).

  2. Hurricane Wind Field Estimation from SeaWinds at Ultra High Resolution

    E-Print Network [OSTI]

    Long, David G.

    Hurricane Wind Field Estimation from SeaWinds at Ultra High Resolution Brent A. Williams and David) are inherently noisier than the standard 25km products and the high rain rates often associated with hurricanes. This paper develops a new procedure for hurricane wind field estimation from the SeaWinds instrument at ultra

  3. Network Wind Power Over the Pacific Northwest. Progress Report, October 1979-September 1980.

    SciTech Connect (OSTI)

    Baker, Robert W.; Hewson, E. Wendell

    1980-10-01T23:59:59.000Z

    The research in FY80 is composed of six primary tasks. These tasks include data collection and analysis, wind flow studies around an operational wind turbine generator (WTG), kite anemometer calibration, wind flow analysis and prediction, the Klickitat County small wind energy conversion system (SWECS) program, and network wind power analysis. The data collection and analysis task consists of four sections, three of which deal with wind flow site surveys and the fourth with collecting and analyzing wind data from existing data stations. This report also includes an appendix which contains mean monthly wind speed data summaries, wind spectrum summaries, time series analysis plots, and high wind summaries.

  4. Rotationally sampled wind characteristics and correlations with MOD-OA wind turbine response

    SciTech Connect (OSTI)

    George, R.L.; Connell, J.R.

    1984-09-01T23:59:59.000Z

    This report presents results of a comprehensive wind and wind turbine measurement program: the Clayton, New Mexico, vertical plane array/MOD-OA project. In this experiment, the turbulent wind was measured for a large array of fixed anemometers located two blade diameters upwind of a 200-kW horizontal-axis wind turbine (HAWT). Simultaneously, key wind turbine response parameters were also measured. The first of two major objectives of this experiment was to determine the turbulent wind, rotationally sampled to emulate the motion of the wind turbine blade, for the range of different wind speeds and stability classes actually experienced by the wind turbine. The second major objective was to correlate this rotationally sampled wind with the wind turbine blade stress and power, in order to assess the usefulness of the wind measurements for wind turbine loads testing a prediction. Time series of rotationally sampled winds and wind turbine blade bending moments and power were converted to frequency spectra using Fourier transform techniques. These spectra were used as the basis for both qualitative and quantitative comparisons among the various cases. A quantitative comparison between the rotationally sampled wind input and blade bending response was made, using the Fourier spectra to estimate the blade transfer function. These transfer functions were then used to calculate an approximate damping coefficient for the MOD-OA fiberglass blade.

  5. Wind Farm

    Office of Energy Efficiency and Renewable Energy (EERE)

    The wind farm in Greensburg, Kansas, was completed in spring 2010, and consists of ten 1.25 megawatt (MW) wind turbines that supply enough electricity to power every house, business, and municipal...

  6. Theoretical X-ray Line Profiles from Colliding Wind Binaries

    E-Print Network [OSTI]

    D. B. Henley; I. R. Stevens; J. M. Pittard

    2003-06-23T23:59:59.000Z

    We present theoretical X-ray line profiles from a range of model colliding wind systems. In particular, we investigate the effects of varying the stellar mass-loss rates, the wind speeds, and the viewing orientation. We find that a wide range of theoretical line profile shapes is possible, varying with orbital inclination and phase. At or near conjunction, the lines have approximately Gaussian profiles, with small widths (HWHM ~ 0.1 v_\\infty) and definite blue- or redshifts (depending on whether the star with the weaker wind is in front or behind). When the system is viewed at quadrature, the lines are generally much broader (HWHM ~ v_\\infty), flat-topped and unshifted. Local absorption can have a major effect on the observed profiles - in systems with mass-loss rates of a few times 10^{-6} Msol/yr the lower energy lines (E wind of the primary. The orbital variation of the line widths and shifts is reduced in a low inclination binary. The extreme case is a binary with i = 0 degrees, for which we would expect no line profile variation.

  7. Wind Energy

    Broader source: Energy.gov [DOE]

    Presentation covers wind energy at the Federal Utility Partnership Working Group (FUPWG) meeting, held on November 18-19, 2009.

  8. Ris-R-Report Grid fault and design-basis for wind turbines -

    E-Print Network [OSTI]

    of the new grid connection requirements for the fatigue and ultimate structural loads of wind turbines analysis for fatigue and ultimate structural loads, respectively, have been performed and compared for two variable speed wind turbines to produce power at wind speeds higher than 25m/s and up to 50m/s without

  9. Ris-R-Report Verification test for three WindCubeTM

    E-Print Network [OSTI]

    sensors mounted at a meteorological mast. Results are presented for three tested units ­ in detail the evaluation of measured mean wind speeds, wind directions and wind speed standard deviations. The data.6 Specifications of reference sensors 10 2.7 Time synchronization 10 3 Procedure of testing (verification test

  10. Quantifying Errors Associated with Satellite Sampling of Offshore Wind S.C. Pryor1,2

    E-Print Network [OSTI]

    1 Quantifying Errors Associated with Satellite Sampling of Offshore Wind Speeds S.C. Pryor1,2 , R, Bloomington, IN47405, USA. Tel: 1-812-855-5155. Fax: 1-812-855-1661 Email: spryor@indiana.edu 2 Dept. of Wind an attractive proposition for measuring wind speeds over the oceans because in principle they also offer

  11. Discrepancies in the Prediction of Solar Wind using Potential Field Source Surface Model: An

    E-Print Network [OSTI]

    Zhao, Xuepu

    Discrepancies in the Prediction of Solar Wind using Potential Field Source Surface Model. This inverse relation has been made use of in the prediction of solar wind speed at 1 AU using a potential between the magnetic flux tube expansion factor (FTE) at the source surface and the solar wind speed

  12. Soft-stall control versus furling control for small wind turbine power regulation

    SciTech Connect (OSTI)

    Muljadi, E.; Forsyth, T.; Butterfield, C.P.

    1998-07-01T23:59:59.000Z

    Many small wind turbines are designed to furl (turn) in high winds to regulate power and provide overspeed protection. Furling control results in poor energy capture at high wind speeds. This paper proposes an alternative control strategy for small wind turbines -- the soft-stall control method. The furling and soft-stall control strategies are compared using steady state analysis and dynamic simulation analysis. The soft-stall method is found to offer several advantages: increased energy production at high wind speeds, energy production which tracks the maximum power coefficient at low to medium wind speeds, reducing furling noise, and reduced thrust.

  13. Soft-Stall Control versus Furling Control for Small Wind Turbine Power Regulation

    SciTech Connect (OSTI)

    Muljadi, E.; Forsyth, T.; Butterfield, C. P.

    1998-07-01T23:59:59.000Z

    Many small wind turbines are designed to furl (turn) in high winds to regulate power and provide overspeed protection. Furling control results in poor energy capture at high wind speeds. This paper proposes an alternative control strategy for small wind turbines -- the soft-stall method. The furling and soft-stall control strategies are compared using steady state analysis and dynamic simulation analysis. The soft-stall method is found to offer several advantages: increased energy production at high wind speeds, energy production which tracks the maximum power coefficient at low to medium wind speeds, reduced furling noise, and reduced thrust.

  14. Guide to Using the WIND Toolkit Validation Code

    SciTech Connect (OSTI)

    Lieberman-Cribbin, W.; Draxl, C.; Clifton, A.

    2014-12-01T23:59:59.000Z

    In response to the U.S. Department of Energy's goal of using 20% wind energy by 2030, the Wind Integration National Dataset (WIND) Toolkit was created to provide information on wind speed, wind direction, temperature, surface air pressure, and air density on more than 126,000 locations across the United States from 2007 to 2013. The numerical weather prediction model output, gridded at 2-km and at a 5-minute resolution, was further converted to detail the wind power production time series of existing and potential wind facility sites. For users of the dataset it is important that the information presented in the WIND Toolkit is accurate and that errors are known, as then corrective steps can be taken. Therefore, we provide validation code written in R that will be made public to provide users with tools to validate data of their own locations. Validation is based on statistical analyses of wind speed, using error metrics such as bias, root-mean-square error, centered root-mean-square error, mean absolute error, and percent error. Plots of diurnal cycles, annual cycles, wind roses, histograms of wind speed, and quantile-quantile plots are created to visualize how well observational data compares to model data. Ideally, validation will confirm beneficial locations to utilize wind energy and encourage regional wind integration studies using the WIND Toolkit.

  15. Hurricane Katrina Wind Investigation Report

    SciTech Connect (OSTI)

    Desjarlais, A. O.

    2007-08-15T23:59:59.000Z

    This investigation of roof damage caused by Hurricane Katrina is a joint effort of the Roofing Industry Committee on Weather Issues, Inc. (RICOWI) and the Oak Ridge National Laboratory/U.S. Department of Energy (ORNL/DOE). The Wind Investigation Program (WIP) was initiated in 1996. Hurricane damage that met the criteria of a major windstorm event did not materialize until Hurricanes Charley and Ivan occurred in August 2004. Hurricane Katrina presented a third opportunity for a wind damage investigation in August 29, 2005. The major objectives of the WIP are as follows: (1) to investigate the field performance of roofing assemblies after major wind events; (2) to factually describe roofing assembly performance and modes of failure; and (3) to formally report results of the investigations and damage modes for substantial wind speeds The goal of the WIP is to perform unbiased, detailed investigations by credible personnel from the roofing industry, the insurance industry, and academia. Data from these investigations will, it is hoped, lead to overall improvement in roofing products, systems, roofing application, and durability and a reduction in losses, which may lead to lower overall costs to the public. This report documents the results of an extensive and well-planned investigative effort. The following program changes were implemented as a result of the lessons learned during the Hurricane Charley and Ivan investigations: (1) A logistics team was deployed to damage areas immediately following landfall; (2) Aerial surveillance--imperative to target wind damage areas--was conducted; (3) Investigation teams were in place within 8 days; (4) Teams collected more detailed data; and (5) Teams took improved photographs and completed more detailed photo logs. Participating associations reviewed the results and lessons learned from the previous investigations and many have taken the following actions: (1) Moved forward with recommendations for new installation procedures; (2) Updated and improved application guidelines and manuals from associations and manufacturers; (3) Launched certified product installer programs; and (4) Submitted building code changes to improve product installation. Estimated wind speeds at the damage locations came from simulated hurricane models prepared by Applied Research Associates of Raleigh, North Carolina. A dynamic hurricane wind field model was calibrated to actual wind speeds measured at 12 inland and offshore stations. The maximum estimated peak gust wind speeds in Katrina were in the 120-130 mph range. Hurricane Katrina made landfall near Grand Isle, Louisiana, and traveled almost due north across the city of New Orleans. Hurricane winds hammered the coastline from Houma, Louisiana, to Pensacola, Florida. The severe flooding problems in New Orleans made it almost impossible for the investigating teams to function inside the city. Thus the WIP investigations were all conducted in areas east of the city. The six teams covered the coastal areas from Bay Saint Louis, Mississippi, on the west to Pascagoula, Mississippi, on the east. Six teams involving a total of 25 persons documented damage to both low slope and steep slope roofing systems. The teams collected specific information on each building examined, including type of structure (use or occupancy), wall construction, roof type, roof slope, building dimensions, roof deck, insulation, construction, and method of roof attachment. In addition, the teams noted terrain exposure and the estimated wind speeds at the building site from the Katrina wind speed map. With each team member assigned a specific duty, they described the damage in detail and illustrated important features with numerous color photos. Where possible, the points of damage initiation were identified and damage propagation described. Because the wind speeds in Katrina at landfall, where the investigations took place, were less than code-specified design speeds, one would expect roof damage to be minimal. One team speculated that damage to all roofs in the area they examined was les

  16. Maximum power tracking control scheme for wind generator systems

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2008-10-10T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  17. Maximum power tracking control scheme for wind generator systems

    E-Print Network [OSTI]

    Mena, Hugo Eduardo

    2009-05-15T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  18. Wind Power Resource Assessment in Ohio and Puerto Rico

    E-Print Network [OSTI]

    Womeldorf, Carole

    Wind Power Resource Assessment in Ohio and Puerto Rico: A Motivational and Educational Tool Juan University, Athens, Ohio Abstract This paper presents an educational guide and example of a wind resource calculations. New data representing wind speed and direction for locations in Ohio and Puerto Rico

  19. Ecosystem feedbacks arising from wind transport in drylands: Results

    E-Print Network [OSTI]

    Ecosystem feedbacks arising from wind transport in drylands: Results from field experiments fire frequency Woody mortality Introduction of exotic grasses Is cover dominated by annuals or short intensity precipitation Low wind speeds Low P/PE High variability High intensity precipitation High wind

  20. The Solar Wind, CMEs and the Origins of Heliospheric Activity

    E-Print Network [OSTI]

    release o Coronal holes o Source of high-speed solar wind #12;peter.gallagher@tcd.ie #12;#12;peter Parker => Parker Spiral: r - r0 = -(v/ )( - 0) o Winding angle: o Inclined at ~45º at 1 AU and ~90º by 10The Solar Wind, CMEs and the Origins of Heliospheric Activity Peter T. Gallagher School of Physics

  1. ForestGALES A PC-based wind risk model

    E-Print Network [OSTI]

    be needed to uproot or break the tree? 3.1 What wind speed would create the force required to damageForestGALES A PC-based wind risk model for British Forests User's Guide Version 2.0 June 2004 Barry by strong winds in Britain 1.1 Historical context ­ Previous predictive windthrow model 1.1 What does Forest

  2. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena, Hugo Eduardo

    2009-05-15T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  3. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2008-10-10T23:59:59.000Z

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  4. IMPLEMENTATION OF WIND TURBINE CONTROLLERS W.E.Leithead

    E-Print Network [OSTI]

    Duffy, Ken

    IMPLEMENTATION OF WIND TURBINE CONTROLLERS D.J.Leith W.E.Leithead Department of Electronic-speed wind turbines are considered, namely, (1) accommodation of the strongly nonlinear rotor aerodynamics derived and extended to cater for all wind turbine configurations. A rigorous stability analysis

  5. Control of Wind Turbines for Power Regulation and

    E-Print Network [OSTI]

    Control of Wind Turbines for Power Regulation and Load Reduction Juan Jose Garcia Quirante Kongens regulation and load reduction and their ensemble in a variable-speed wind turbine. The power regulation aspects of mathematical modelling of wind turbines, and especially the control methods suited for power

  6. Taming Hurricanes With Arrays of Offshore Wind Turbines

    E-Print Network [OSTI]

    Firestone, Jeremy

    Taming Hurricanes With Arrays of Offshore Wind Turbines Mark Z. Jacobson Cristina Archer, Willet) or 50 m/s (destruction) speed. Can Walls of Offshore Wind Turbines Dissipate Hurricanes? #12;Katrina Kempton Wind Energy Symposium University of Delaware February 27, 2013 145 mph; Jeff Schmaltz, NASA GSFC

  7. Floating Offshore Wind Technology Generating Resources Advisory Committee

    E-Print Network [OSTI]

    Floating Offshore Wind Technology Jeff King Generating Resources Advisory Committee May 28, 2014 1 to site) Potential interconnection to future offshore PNWCA intertie 4 #12;5 Ave wind speed >= 10 m. (2010) Large-scale Offshore Wind Power in the United States National Renewable Energy Laboratory. (2012

  8. Optimizing small wind turbine performance in battery charging applications

    SciTech Connect (OSTI)

    Drouilhet, S; Muljadi, E; Holz, R [National Renewable Energy Lab., Golden, CO (United States). Wind Technology Div.; Gevorgian, V [State Engineering Univ. of Armenia, Yerevan (Armenia)

    1995-05-01T23:59:59.000Z

    Many small wind turbine generators (10 kW or less) consist of a variable speed rotor driving a permanent magnet synchronous generator (alternator). One application of such wind turbines is battery charging, in which the generator is connected through a rectifier to a battery bank. The wind turbine electrical interface is essentially the same whether the turbine is part of a remote power supply for telecommunications, a standalone residential power system, or a hybrid village power system, in short, any system in which the wind generator output is rectified and fed into a DC bus. Field experience with such applications has shown that both the peak power output and the total energy capture of the wind turbine often fall short of expectations based on rotor size and generator rating. In this paper, the authors present a simple analytical model of the typical wind generator battery charging system that allows one to calculate actual power curves if the generator and rotor properties are known. The model clearly illustrates how the load characteristics affect the generator output. In the second part of this paper, the authors present four approaches to maximizing energy capture from wind turbines in battery charging applications. The first of these is to determine the optimal battery bank voltage for a given WTG. The second consists of adding capacitors in series with the generator. The third approach is to place an optimizing DC/DC voltage converter between the rectifier and the battery bank. The fourth is a combination of the series capacitors and the optimizing voltage controller. They also discuss both the limitations and the potential performance gain associated with each of the four configurations.

  9. Performance of a stand-alone wind-electric ice maker for remote villages

    SciTech Connect (OSTI)

    Davis, H.C. [National Renewable Energy Lab., Golden, CO (United States); Brandemuehl, M.J. [University of Colorado, Boulder, CO (United States). Joint Center for Energy Management; Bergey, M.L.S. [Bergey Windpower Co., Norman, OK (United States)

    1995-01-01T23:59:59.000Z

    Two ice makers in the 1.1 metric tons per 24 hours (1.2 tons per day) size range were tested to determine their performance when directly coupled to a variable-frequency wind turbine generator. Initial tests were conducted using a dynamometer to simulate to wind to evaluate whether previously determined potential problems were significant and to define basic performance parameters. Field testing in Norman, Oklahoma, was completed to determine the performance of one of the ice makers under real wind conditions. As expected, the ice makers produced more ice at a higher speed than rated, and less ice at a lower speed. Due to the large start-up torque requirement of reciprocating compressors, the ice making system experienced a large start-up current and corresponding voltage drop which required a larger wind turbine that expected to provide the necessary current and voltage. Performance curves for ice production and power consumption are presented. A spreadsheet model was constructed to predict ice production at a user-defined site given the wind conditions for that location. Future work should include long-term performance tests and research on reducing the large start-up currents the system experiences when first coming on line.

  10. Estimating long-term mean winds from short-term wind data

    SciTech Connect (OSTI)

    Barchet, W.R.; Davis, W.E.

    1983-08-01T23:59:59.000Z

    The estimation of long-term mean winds from short-term data is especially important in the area of wind energy. It is desirable to obtain reliable estimates of the long-term wind speed from as short a period of on-site measurements as possible. This study examined seven different methods of estimating the long-term average wind speed and compared the performance of these techniques. Three linear, three weather pattern, and one eigenvector methods were compared for measurement periods ranging from 3 months to 36 months. Average errors, both relative and absolute, and the rms errors in the techniques were determined. The best technique for less than 12 months of measurement was the eigenvector method using weekly mean wind speeds. However, this method was only slightly better than the linear adjusted method. When 12 or more months of data were used, the difference in errors between techniques was found to be slight.

  11. Effectiveness of speed trailers on low-speed urban roadways

    E-Print Network [OSTI]

    Perrillo, Kerry Victoria

    1997-01-01T23:59:59.000Z

    Efforts are being made to use speed management methods to match operating speeds to posted speeds and to reduce the variability in vehicle speeds. The effectiveness of many different methods of speed management has not been documented. This thesis...

  12. Effects of increasing tip velocity on wind turbine rotor design.

    SciTech Connect (OSTI)

    Resor, Brian Ray; Maniaci, David Charles; Berg, Jonathan Charles; Richards, Phillip William

    2014-05-01T23:59:59.000Z

    A reduction in cost of energy from wind is anticipated when maximum allowable tip velocity is allowed to increase. Rotor torque decreases as tip velocity increases and rotor size and power rating are held constant. Reduction in rotor torque yields a lighter weight gearbox, a decrease in the turbine cost, and an increase in the capacity for the turbine to deliver cost competitive electricity. The high speed rotor incurs costs attributable to rotor aero-acoustics and system loads. The increased loads of high speed rotors drive the sizing and cost of other components in the system. Rotor, drivetrain, and tower designs at 80 m/s maximum tip velocity and 100 m/s maximum tip velocity are created to quantify these effects. Component costs, annualized energy production, and cost of energy are computed for each design to quantify the change in overall cost of energy resulting from the increase in turbine tip velocity. High fidelity physics based models rather than cost and scaling models are used to perform the work. Results provide a quantitative assessment of anticipated costs and benefits for high speed rotors. Finally, important lessons regarding full system optimization of wind turbines are documented.

  13. 756 IEEE TRANSACTIONS ON SUSTAINABLE ENERGY, VOL. 4, NO. 3, JULY 2013 Minimization of Wind Farm Operational

    E-Print Network [OSTI]

    Kusiak, Andrew

    756 IEEE TRANSACTIONS ON SUSTAINABLE ENERGY, VOL. 4, NO. 3, JULY 2013 Minimization of Wind Farm, and Guanglin Xu Abstract--Scheduling a wind farm in the presence of uncertain wind speed conditions the operational status and control settings of a wind turbine. The cost of operating a wind farm according

  14. Abstract--This paper proposes a stochastic wind power model based on an autoregressive integrated moving average (ARIMA)

    E-Print Network [OSTI]

    Bak-Jensen, Birgitte

    of one year from the Nysted offshore wind farm in Denmark. The proposed limited-ARIMA (LARIMA) model be applied to planning of future wind farms in the power system. However, both approaches entail wind speed measurements and an accurate wind farm model, which is usually unavailable. The accurate wind farm model

  15. PowerJet Wind Turbine Project

    SciTech Connect (OSTI)

    Bartlett, Raymond J

    2008-11-30T23:59:59.000Z

    PROJECT OBJECTIVE The PowerJet wind turbine overcomes problems characteristic of the small wind turbines that are on the market today by providing reliable output at a wide range of wind speeds, durability, silent operation at all wind speeds, and bird-safe operation. Prime Energy�s objective for this project was to design and integrate a generator with an electrical controller and mechanical controls to maximize the generation of electricity by its wind turbine. The scope of this project was to design, construct and test a mechanical back plate to control rotational speed in high winds, and an electronic controller to maximize power output and to assist the base plate in controlling rotational speed in high winds. The test model will continue to operate beyond the time frame of the project, with the ultimate goal of manufacturing and marketing the PowerJet worldwide. Increased Understanding of Electronic & Mechanical Controls Integrated With Electricity Generator The PowerJet back plate begins to open as wind speed exceeds 13.5 mps. The pressure inside the turbine and the turbine rotational speed are held constant. Once the back plate has fully opened at approximately 29 mps, the controller begins pulsing back to the generator to limit the rotational speed of the turbine. At a wind speed in excess of 29 mps, the controller shorts the generator and brings the turbine to a complete stop. As the wind speed subsides, the controller releases the turbine and it resumes producing electricity. Data collection and instrumentation problems prevented identification of the exact speeds at which these events occur. However, the turbine, controller and generator survived winds in excess of 36 mps, confirming that the two over-speed controls accomplished their purpose. Technical Effectiveness & Economic Feasibility Maximum Electrical Output The output of electricity is maximized by the integration of an electronic controller and mechanical over-speed controls designed and tested during the course of this project. The output exceeds that of the PowerJet�s 3-bladed counterparts (see Appendix). Durability All components of the PowerJet turbine assembly�including the electronic and mechanical controls designed, manufactured and field tested during the course of this project�proved to be durable through severe weather conditions, with constant operation and no interruption in energy production. Low Cost Materials for the turbine, generator, tower, charge controllers and ancillary parts are available at reasonable prices. Fabrication of these parts is also readily available worldwide. The cost of assembling and installing the turbine is reduced because it has fewer parts and requires less labor to manufacture and assemble, making it competitively priced compared with turbines of similar output manufactured in the U.S. and Europe. The electronic controller is the unique part to be included in the turbine package. The controllers can be manufactured in reasonably-sized production runs to keep the cost below $250 each. The data logger and 24 sensors are for research only and will be unnecessary for the commercial product. Benefit To Public The PowerJet wind-electric system is designed for distributed wind generation in 3 and 4 class winds. This wind turbine meets DOE�s requirements for a quiet, durable, bird-safe turbine that eventually can be deployed as a grid-connected generator in urban and suburban settings. Results As described more fully below and illustrated in the Appendices, the goals and objectives outlined in 2060 SOPO were fully met. Electronic and mechanical controls were successfully designed, manufactured and integrated with the generator. The turbine, tower, controllers and generators operated without incident throughout the test period, surviving severe winter and summer weather conditions such as extreme temperatures, ice and sustained high winds. The electronic controls were contained in weather-proof electrical boxes and the elec

  16. Minimizing Variation in Outdoor CPV Power Ratings (Presentation)

    SciTech Connect (OSTI)

    Muller, M.

    2011-04-01T23:59:59.000Z

    Presented at the 7th International Conference on Concentrating Photovoltaic Systems (CPV-7), 4-6 April 2011, Las Vegas, Nevada. The CPV community has agreed to have both indoor and outdoor power ratings at the module level. The indoor rating provides a repeatable measure of module performance as it leaves the factory line while the outdoor rating provides a measure of true performance under real world conditions. The challenge with an outdoor rating is that the spectrum, temperature, wind speed, etc are constantly in flux and therefore the resulting power rating varies from day to day and month to month. This work examines different methodologies for determining the outdoor power rating with the goal of minimizing variation even if data are collected under changing meteorological conditions.

  17. Sandia National Laboratories: Wind

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Wind Grid System Planning for Wind: Wind Generator Modeling On June 11, 2014, in Wind generation continues to dominate the interconnection queues and the need for generic,...

  18. Analysis of wind power for battery charging

    SciTech Connect (OSTI)

    Muljadi, E.; Drouilhet, S.; Holz, R. [National Renewable Energy Lab., Golden, CO (United States); Gevorgian, V. [University of Armenia, Yerevan (Armenia). State Engineering

    1995-11-01T23:59:59.000Z

    One type of wind-powered battery charging will be explored in this paper. It consists of a wind turbine driving a permanent magnet alternator and operates at variable speed. The alternator is connected to a battery bank via a rectifier. The characteristic of the system depends on the wind turbine, the alternator, and the system configuration. If the electrical load does not match the wind turbine, the performance of the system will be degraded. By matching the electrical load to the wind turbine, the system can be improved significantly. This paper analyzes the properties of the system components. The effects of parameter variation and the system configuration on the system performance are investigated. Two basic methods of shaping the torque-speed characteristic of the generator are presented. The uncompensated as well as the compensated systems will be discussed. Control strategies to improve the system performance will be explored. Finally, a summary of the paper will be presented in the last section.

  19. Effect of Wind Intermittency on the Electric Grid: Mitigating the Risk of Energy Deficits

    E-Print Network [OSTI]

    George, Sam O; Nguyen, Scott V

    2010-01-01T23:59:59.000Z

    Successful implementation of California's Renewable Portfolio Standard (RPS) mandating 33 percent renewable energy generation by 2020 requires inclusion of a robust strategy to mitigate increased risk of energy deficits (blackouts) due to short time-scale (sub 1 hour) intermittencies in renewable energy sources. Of these RPS sources, wind energy has the fastest growth rate--over 25% year-over-year. If these growth trends continue, wind energy could make up 15 percent of California's energy portfolio by 2016 (wRPS15). However, the hour-to-hour variations in wind energy (speed) will create large hourly energy deficits that require installation of other, more predictable, compensation generation capacity and infrastructure. Compensating for the energy deficits of wRPS15 could potentially cost tens of billions in additional dollar-expenditure for fossil and / or nuclear generation capacity. There is a real possibility that carbon dioxide and other greenhouse gas (GHG) emission reductions will miss the California ...

  20. Sandia National Laboratories: increasing average wind turbine...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wind turbine power rating Latest Version of the Composite Materials Database Available for Download On December 3, 2014, in Energy, Materials Science, News, News & Events,...

  1. Definition of a 5-MW Reference Wind Turbine for Offshore System Development

    SciTech Connect (OSTI)

    Jonkman, J.; Butterfield, S.; Musial, W.; Scott, G.

    2009-02-01T23:59:59.000Z

    This report describes a three-bladed, upwind, variable-speed, variable blade-pitch-to-feather-controlled multimegawatt wind turbine model developed by NREL to support concept studies aimed at assessing offshore wind technology.

  2. Stochastic Real-Time Scheduling of Wind-thermal Generation Units ...

    E-Print Network [OSTI]

    2014-11-11T23:59:59.000Z

    time t (MW) wps,t. Percent of wind farm capacity available at scenario s and time t .... speeds at foreseen onshore and offshore wind farms locations is proposed.

  3. Influence of large scale oscillations on upwelling-favorable coastal wind off central Chile

    E-Print Network [OSTI]

    Rahn, David A.

    2012-10-16T23:59:59.000Z

    Along the central coast of Chile is typically equatorward, upwelling-favorable wind associated with the southeast Pacific anticyclone. A coastal low-level jet often develops, and its wind speed is mostly controlled by the meridional pressure...

  4. TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW

    E-Print Network [OSTI]

    Isenberg, Philip A.

    Previous models of solar wind heating by interstellar pickup proton-driven turbulence have assumed that the wind speed is a constant in heliocentric radial position. However, the same pickup process, which is taken to ...

  5. Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

    Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine-Frequency Control (LFC) is gradually shifted to Variable Speed Wind Turbines (VSWTs). In order to equip VSWT

  6. Quantifying the system balancing cost when wind energy is incorporated into electricity generation system 

    E-Print Network [OSTI]

    Issaeva, Natalia

    2009-01-01T23:59:59.000Z

    Incorporation of wind energy into the electricity generation system requires a detailed analysis of wind speed in order to minimize system balancing cost and avoid a significant mismatch between supply and demand. Power ...

  7. 1 Introduction The development of wind energy use has led to

    E-Print Network [OSTI]

    Heinemann, Detlev

    1 Introduction The development of wind energy use has led to a noticeable contribution in of electricity by wind energy acts as a negative load leading to an increase in fluctuations of net load patterns conventional reserves have to be kept ready to replace the wind energy share in case of decreasing wind speeds

  8. Lidars in Wind Energy Jakob Mann, Ferhat Bingl, Torben Mikkelsen, Ioannis Antoniou, Mike

    E-Print Network [OSTI]

    Lidars in Wind Energy Jakob Mann, Ferhat Bingöl, Torben Mikkelsen, Ioannis Antoniou, Mike Courtney, Gunner Larsen, Ebba Dellwik Juan Jose Trujillo* and Hans E. Jørgensen Wind Energy Department Risø of the presentation · Introduction to wind energy · Accurate profiles of the mean wind speed · Wakes behind turbines

  9. Calibrated Probabilistic Forecasting at the Stateline Wind Energy Center: The Regime-Switching

    E-Print Network [OSTI]

    Genton, Marc G.

    Calibrated Probabilistic Forecasting at the Stateline Wind Energy Center: The Regime at a wind energy site and fits a conditional predictive model for each regime. Geographically dispersed was applied to 2-hour-ahead forecasts of hourly average wind speed near the Stateline wind energy center

  10. A Unified Framework for Reliability Assessment of Wind Energy Conversion Systems

    E-Print Network [OSTI]

    Liberzon, Daniel

    1 A Unified Framework for Reliability Assessment of Wind Energy Conversion Systems Sebastian S a framework for assessing wind energy conversion systems (WECS) reliability in the face of external based on wind energy are: the impact of wind speed variability on system reliability [1]; WECS' reaction

  11. American Wind Energy Association, Denver, May 2005 Uncertainties in Results of Measure-Correlate-Predict Analyses

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    American Wind Energy Association, Denver, May 2005 Uncertainties in Results of Measure-correlate-predict (MCP) algorithms are used to predict the wind resource at target sites for wind power development. MCP methods model the relationship between wind data (speed and direction) measured at the target site

  12. PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL

    E-Print Network [OSTI]

    Duffy, Ken

    PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL D.J.Leith W Power regulation of horizontal-axis grid-connected up-wind constant-speed pitch-regulated wind turbines ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL D.J.Leith W.E.Leithead Department

  13. Seed dispersal by wind: towards a conceptual framework of seed abscission and its contribution to

    E-Print Network [OSTI]

    Katul, Gabriel

    above some threshold wind speed and (ii) depends on the drag force generated by the wind. 2. We revisitSeed dispersal by wind: towards a conceptual framework of seed abscission and its contribution determines many aspects of seed dispersal by wind. While there is yet no complete mechanistic framework

  14. Session: Poster Session + Poster Award + Scientific Award + Excellent young wind doctor award (PO.206) Track: Technical

    E-Print Network [OSTI]

    Session: Poster Session + Poster Award + Scientific Award + Excellent young wind doctor award (PO.206) Track: Technical INVESTIGATION OF THE MEASUREMENT OF THE WIND SPEED STANDARD DEVIATION USING) Siemens wind power The LiDAR seems to be an effective alternative to met masts measurements of wind

  15. Amplitude modulation of wind turbine noise

    E-Print Network [OSTI]

    Makarewicz, Rufin

    2013-01-01T23:59:59.000Z

    Due to swish and thump amplitude modulation, the noise of wind turbines cause more annoyance than other environmental noise of the same average level. The wind shear accounts for the thump modulation (van den Berg effect). Making use of the wind speed measurements at the hub height, as well as at the top and the bottom of the rotor disc (Fig.1), the non-standard wind profile is applied. It causes variations in the A-weighted sound pressure level, LpA. The difference between the maximum and minimum of LpA characterizes thump modulation (Fig.2).

  16. Sandia Wind Turbine Loads Database

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Sandia Wind Turbine Loads Database is divided into six files, each corresponding to approximately 16 years of simulation. The files are text files with data in columnar format. The 424MB zipped file containing six data files can be downloaded by the public. The files simulate 10-minute maximum loads for the NREL 5MW wind turbine. The details of the loads simulations can be found in the paper: “Decades of Wind Turbine Loads Simulations”, M. Barone, J. Paquette, B. Resor, and L. Manuel, AIAA2012-1288 (3.69MB PDF). Note that the site-average wind speed is 10 m/s (class I-B), not the 8.5 m/s reported in the paper.

  17. Previous Wind Power Announcements (generation/wind)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah ProjectPRE-AWARDenergyEnergytransmission-rates Sign In About |Wind

  18. Wind energy resource atlas. Volume 3. Great Lakes Region

    SciTech Connect (OSTI)

    Paton, D.L.; Bass, A.; Smith, D.G.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01T23:59:59.000Z

    The Great Lakes Region atlas assimilates six collections of wind resource data, one for the region and one for each of the five states that compose the Great Lakes region: Illinois, Indiana, Michigan, Ohio, Wisconsin. At the state level, features of the climate, topography, and wind resource are discussed in greater detail than in the regional discussion and the data locations on which the assessment is based are mapped. Variations over several time scales in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and of hourly average wind speed for each season. Other graphs present speed, direction, and duration frequencies of the wind at these locations.

  19. Wind energy resource atlas: Volume 6. The Southeast region

    SciTech Connect (OSTI)

    Zabransky, J.; Vilardo, J.M.; Schakenbach, J.T.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-01-01T23:59:59.000Z

    The Southeast atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the Southeast region (Alabama, Florida, Georgia, Mississippi, and South Carolina). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and the data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and hourly average wind speed for each season. Other graphs present speed, direction and duration frequencies of the wind at these locations.

  20. Wind energy resource atlas. Volume 2. The North Central Region

    SciTech Connect (OSTI)

    Freeman, D.L.; Hadley, D.L.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01T23:59:59.000Z

    The North Central atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the North Central region (Iowa, Minnesota, Nebraska, North Dakota, and South Dakota). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and that data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and international wind speed and power, and hourly average wind speed for each season. Other graphs present speed direction and duration frequencies of the wind at these locations.

  1. Wind energy resource atlas. Volume 7. The south central region

    SciTech Connect (OSTI)

    Edwards, R.L.; Graves, L.F.; Sprankle, A.C.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-03-01T23:59:59.000Z

    This atlas of the south central region combines seven collections of wind resource data: one for the region, and one for each of the six states (Arkansas, Kansas, Louisiana, Missouri, Oklahoma, and Texas). At the state level, features of the climate, topography, and wind resource are discussed in greater detail than that provided in the regional discussion, and the data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and interannual wind speed and power, and hourly average wind speed for each season. Other graphs present speed, direction, and duration frequencies of the wind at these locations.

  2. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems /

    E-Print Network [OSTI]

    Ghaffari, Azad

    2013-01-01T23:59:59.000Z

    solar irradiance, and wind speed. Maximum Power Point Tracking (Tracking Since PV and WECS power level are defined by the environmental param- eters like solar

  3. Synoptic and local influences on boundary layer processes, with an application to California wind power

    E-Print Network [OSTI]

    Mansbach, David K.

    2010-01-01T23:59:59.000Z

    of observed summertime mesoscale pressure gradient and ??observed wind speeds and mesoscale SLP di?erences at pointsand modi?cation of mesoscale circulations. Monthly Weather

  4. Preliminary design and viability consideration of external, shroud-based stators in wind turbine generators

    E-Print Network [OSTI]

    Shoemaker-Trejo, Nathaniel (Nathaniel Joseph)

    2012-01-01T23:59:59.000Z

    Horizontal-axis wind turbine designs often included gearboxes or large direct-drive generators to compensate for the low peripheral speeds of the turbine hub. To take advantage of high blade tip speeds, an alternative ...

  5. Aeroacoustic Testing of Wind Turbine Airfoils: February 20, 2004 - February 19, 2008

    SciTech Connect (OSTI)

    Devenport, W.; Burdisso, R. A.; Camargo, H.; Crede, E.; Remillieux, M.; Rasnick, M.; Van Seeters, P.

    2010-05-01T23:59:59.000Z

    The U.S. Department of Energy (DOE), working through its National Renewable Energy Laboratory (NREL), is engaged in a comprehensive research effort to improve the understanding of wind turbine aeroacoustics. The motivation for this effort is the desire to exploit the large expanse of low wind speed sites that tend to be close to U.S. load centers. Quiet wind turbines are an inducement to widespread deployment, so the goal of NREL's aeroacoustic research is to develop tools that the U.S. wind industry can use in developing and deploying highly efficient, quiet wind turbines at low wind speed sites. NREL's National Wind Technology Center (NWTC) is implementing a multifaceted approach that includes wind tunnel tests, field tests, and theoretical analyses in direct support of low wind speed turbine development by its industry partners. NWTC researchers are working hand in hand with engineers in industry to ensure that research findings are available to support ongoing design decisions.

  6. Operational risk of a wind farm energy production by Extreme Value Theory and Copulas

    E-Print Network [OSTI]

    D'Amico, Guglielmo; Prattico, Flavio

    2014-01-01T23:59:59.000Z

    In this paper we use risk management techniques to evaluate the potential effects of those operational risks that affect the energy production of a wind farm. We concentrate our attention on three major risk factors: wind speed uncertainty, wind turbine reliability and interactions of wind turbines due mainly to their placement. As a first contribution, we show that the Weibull distribution, commonly used to fit recorded wind speed data, underestimates rare events. Therefore, in order to achieve a better estimation of the tail of the wind speed distribution, we advance a Generalized Pareto distribution. The wind turbines reliability is considered by modeling the failures events as a compound Poisson process. Finally, the use of Copula able us to consider the correlation between wind turbines that compose the wind farm. Once this procedure is set up, we show a sensitivity analysis and we also compare the results from the proposed procedure with those obtained by ignoring the aforementioned risk factors.

  7. Offshore Wind Power USA

    Broader source: Energy.gov [DOE]

    The Offshore Wind Power USA conference provides the latest offshore wind market updates and forecasts.

  8. Discrepancies in the prediction of solar wind using potential field source surface model: An investigation of possible sources

    E-Print Network [OSTI]

    California at Berkeley, University of

    Discrepancies in the prediction of solar wind using potential field source surface model expansion factor (FTE) at the source surface and the solar wind speed (SWS) observed at Earth, which has been made use of in the prediction of solar wind speed near the Earth with reasonable accuracy. However

  9. Analysis of a teetered, variable-speed rotor: final report

    SciTech Connect (OSTI)

    Weber, T.L.; Wilson, R.E.; Walker, S.N. (Oregon State Univ., Corvallis, OR (USA). Dept. of Mechanical Engineering) [Oregon State Univ., Corvallis, OR (USA). Dept. of Mechanical Engineering

    1991-06-01T23:59:59.000Z

    A computer model of a horizontal axis wind turbine (HOOT) with four structural degrees of freedom has been derived and verified. The four degrees of freedom include flapwise motion of the blades, teeter motion, and variable rotor speed. Options for the variable rotor speed include synchronous, induction, and constant-tip speed generator models with either start, stop, or normal operations. Verification is made by comparison with analytical solutions and mean and cyclic ESI-80 data. The Veers full-field turbulence model is used as a wind input for a synchronous and induction generator test case during normal operation. As a result of the comparison, it is concluded that the computer model can be used to predict accurately mean and cyclic loads with a turbulent wind input. 47 refs., 19 figs.

  10. Wind Energy Leasing Handbook

    E-Print Network [OSTI]

    Balasundaram, Balabhaskar "Baski"

    Wind Energy Leasing Handbook Wind Energy Leasing Handbook E-1033 Oklahoma Cooperative Extension?..................................................................................................................... 31 What do wind developers consider in locating wind energy projects?............................................................................................ 37 How do companies and individuals invest in wind energy projects?....................................................................

  11. Wind: wind speed and wind power density GIS data at 10m and 50m...

    Open Energy Info (EERE)

    tionalrenewableenergylaboratorynrel National Renewable Energy Laboratory (NREL) There is no description for this organization Social Google+ Twitter Facebook License odc-pddl...

  12. Wind: wind speed and wind power density maps at 10m and 50m above...

    Open Energy Info (EERE)

    the U.S. Department of Energy ("DOE"). The user is granted the right, without any fee or cost, to use, copy, modify, alter, enhance and distribute this data for any purpose...

  13. Main Coast Winds - Final Scientific Report

    SciTech Connect (OSTI)

    Jason Huckaby; Harley Lee

    2006-03-15T23:59:59.000Z

    The Maine Coast Wind Project was developed to investigate the cost-effectiveness of small, distributed wind systems on coastal sites in Maine. The restructuring of Maine's electric grid to support net metering allowed for the installation of small wind installations across the state (up to 100kW). The study performed adds insight to the difficulties of developing cost-effective distributed systems in coastal environments. The technical hurdles encountered with the chosen wind turbine, combined with the lower than expected wind speeds, did not provide a cost-effective return to make a distributed wind program economically feasible. While the turbine was accepted within the community, the low availability has been a negative.

  14. Advanced Coal Wind Hybrid: Economic Analysis

    E-Print Network [OSTI]

    Phadke, Amol

    2008-01-01T23:59:59.000Z

    2008) find estimates of capital cost of wind projectsHowever, our estimates of costs (e.g. , capital costs) ofin capital costs. 26 Heat Rate Heat rate estimates for the

  15. Winding Trail 

    E-Print Network [OSTI]

    Unknown

    2011-09-05T23:59:59.000Z

    During the past decade, the demand for clean renewable energy continues to rise drastically in Europe, the US, and other countries. Wind energy in the ocean can possibly be one of those future renewable clean energy sources as long...

  16. Influence of the airflow speed along transmission lines on the DC corona discharge loss, using finite element approach

    SciTech Connect (OSTI)

    Shemshadi, A.; Akbari, A. [Electric Department, K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of); Niayesh, K. [Electric Engineering Department, Tehran University, Tehran (Iran, Islamic Republic of)

    2012-07-15T23:59:59.000Z

    Corona discharge is of great interest from the physical point of view and due to its numerous practical applications in industry and especially one of the most important sources of loss in the high voltage transmission lines. This paper provides guidelines for the amount of electric loss caused by corona phenomenon occurred around a DC high voltage wire placed between two flat plates and influence of wind speed rate on the amount of corona loss using COMSOL Multiphysics. So electric potential distribution patterns and charge density diffusion around the wire are studied in this article.

  17. Wind Energy Benefits, Wind Powering America (WPA) (Fact Sheet...

    Broader source: Energy.gov (indexed) [DOE]

    Energy Benefits, Wind Powering America (WPA) (Fact Sheet), Wind And Water Power Program (WWPP) Wind Energy Benefits, Wind Powering America (WPA) (Fact Sheet), Wind And Water Power...

  18. Meteorological aspects of siting large wind turbines

    SciTech Connect (OSTI)

    Hiester, T.R.; Pennell, W.T.

    1981-01-01T23:59:59.000Z

    This report, which focuses on the meteorological aspects of siting large wind turbines (turbines with a rated output exceeding 100 kW), has four main goals. The first is to outline the elements of a siting strategy that will identify the most favorable wind energy sites in a region and that will provide sufficient wind data to make responsible economic evaluations of the site wind resource possible. The second is to critique and summarize siting techniques that were studied in the Department of Energy (DOE) Wind Energy Program. The third goal is to educate utility technical personnel, engineering consultants, and meteorological consultants (who may have not yet undertaken wind energy consulting) on meteorological phenomena relevant to wind turbine siting in order to enhance dialogues between these groups. The fourth goal is to minimize the chances of failure of early siting programs due to insufficient understanding of wind behavior.

  19. Experimental Investigation of Wind-Forced Drop Stability

    E-Print Network [OSTI]

    Schmucker, Jason

    2012-10-19T23:59:59.000Z

    aluminum (RA = 3.26 micrometers) floor of a tiltable wind tunnel and brought to critical conditions, when the drop begins to run downstream. Various combinations of drop size, inclination angle, and flow speed were employed. A measurement technique capable...

  20. american large wind: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    layer of the flow, waves whose phase velocity is equal to the horizontal wind speed have negligible energy. This indicates a nonlocal transfer of their energy to the mean...

  1. Characteristics of Wind Turbines Under Normal and Fault Conditions: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C. P.; Parsons, B.; Ellis, A.

    2007-02-01T23:59:59.000Z

    This paper investigates the characteristics of a variable-speed wind turbine connected to a stiff or weak grid under normal and fault conditions and the role of reactive power compensation.

  2. Model Predictive Control of a Wind Aleksander Gosk

    E-Print Network [OSTI]

    -3192 #12;Summary In the era of growing interest in limiting CO2 emission and our dependence on fossil fuels are aiming for maximizing the produced electric power for some range of wind speeds and keeping it constant

  3. Passive aeroelastic tailoring of wind turbine blades : a numerical analysis

    E-Print Network [OSTI]

    Deilmann, Christian

    2009-01-01T23:59:59.000Z

    This research aims to have an impact towards a sustainable energy supply. In wind power generation losses occur at tip speed ratios which the rotor was not designed for. Since the ideal blade shape changes nonlinearly with ...

  4. Time changes in gradient and observed winds

    E-Print Network [OSTI]

    Carlson, Ronald Dale

    1972-01-01T23:59:59.000Z

    - cal purposes, represents the changes in the components of the gradient wind speed, as calculated from Eqs. (9) and (10). Equations (9) and (10) were solved by the use of finite dif- ference methods. Due to the long incremental time steps, 3 to 12... hours, the changes in the components of the gradient wind speed obtained numerically from Eqs. (9) and (10) may differ slightly from the changes observed due to the numerical techniques employed. How- ever, the patterns obtained by the two methods...

  5. NREL Develops New Controls that Proactively Adapt to the Wind (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-11-01T23:59:59.000Z

    Until now, wind turbine controls that reduce the impacts of wind gusts and turbulence were always reactive-responding to the wind rather than anticipating it. But with today's laser-based sensors that measure wind speed ahead of the turbine, researchers at the National Renewable Energy Laboratory (NREL) and their industry partners are developing more intelligent controls. The world's first field tests of these controls are currently underway at the National Wind Technology Center (NWTC) at NREL, with plans for future commercialization.

  6. NREL Develops New Controls that Proactively Adapt to the Wind (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-10-01T23:59:59.000Z

    Until now, wind turbine controls that reduce the impacts of wind gusts and turbulence were always reactive -- responding to the wind rather than anticipating it. But with today's laser-based sensors that measure wind speed ahead of the turbine, researchers at the National Renewable Energy Laboratory (NREL) and their industry partners are developing more intelligent controls. The world's first field tests of these controls are currently underway at the National Wind Technology Center (NWTC) at NREL, with plans for future commercialization.

  7. Content Provider Speeds Application

    E-Print Network [OSTI]

    Fisher, Kathleen

    protocols like SMPP for SMS and MM7 for MMS are industry standards, carriers typically layer their own APIs.0 standards," says Rose, "and we thought that would help speed development." The AT&T API Platform includesContent Provider Speeds Application Development AT&T API Platform cuts development time and costs

  8. Variability of wind power near Oklahoma City and implications for siting of wind turbines

    SciTech Connect (OSTI)

    Kessler, E.; Eyster, R.

    1987-09-01T23:59:59.000Z

    Data from five sites near Oklahoma City were examined to assess wind power availability. Wind turbines of identical manufacture were operated at three of the sites, one of which was also equipped with anemometers on a 100-ft tower. Comprehensive anemometric data were available from the other two sites. The study indicates that the average wind speed varies substantially over Oklahoma's rolling plains, which have often been nominally regarded as flat for purposes of wind power generation. Average wind differences may be as much as 5 mph at 20 ft above ground level, and 7 mph at 100 ft above ground level for elevation differences of about 200 ft above mean sea level, even in the absence of substantial features of local terrain. Local altitude above mean sea level seems to be as influential as the shape of local terrain in determining the average wind speed. The wind turbine used at a meteorologically instrumented site in the study produced the power expected from it for the wind regime in which it was situated. The observed variations of local wind imply variations in annual kWh of as much as a factor of four between identical turbines located at similar heights above ground level in shallow valleys and on hilltops or elevated extended flat areas. 17 refs., 39 figs., 11 tabs.

  9. The Roles of Reconnected Flux and Overlying Fields in CME Speeds

    E-Print Network [OSTI]

    Deng, Minda

    2015-01-01T23:59:59.000Z

    The standard model of eruptive, two-ribbon flares involves reconnection of over- lying magnetic fields beneath a rising ejection. Numerous observers have reported evidence linking this reconnection, indicated by photospheric flux swept out by flare ribbons, to coronal mass ejection (CME) acceleration. This acceleration might be caused by reconnected fields that wrap around the ejection producing an increased outward hoop force. Other observations have linked stronger over- lying fields, measured by the power-law index of the fitted decay rate of field strength overlying eruption sites, to slower CME speeds. This might be caused by greater downward magnetic tension in stronger overlying fields. So overlying fields might both help and hinder the acceleration of CMEs: reconnection that converts overlying fields into flux winding about the ejection might help, but unreconnected overlying fields might hurt. Here, we investigate the roles of both ribbon fluxes and the decay rates of overlying fields in a set of 16 ...

  10. On the Patterns of Wind-Power Input to the Ocean Circulation

    E-Print Network [OSTI]

    Roquet, Fabien

    Pathways of wind-power input into the ocean general circulation are analyzed using Ekman theory. Direct rates of wind work can be calculated through the wind stress acting on the surface geostrophic flow. However, because ...

  11. Energy 101: Wind Turbines

    ScienceCinema (OSTI)

    None

    2013-05-29T23:59:59.000Z

    See how wind turbines generate clean electricity from the power of the wind. Highlighted are the various parts and mechanisms of a modern wind turbine.

  12. Energy 101: Wind Turbines

    SciTech Connect (OSTI)

    None

    2011-01-01T23:59:59.000Z

    See how wind turbines generate clean electricity from the power of the wind. Highlighted are the various parts and mechanisms of a modern wind turbine.

  13. Wind Tunnel Aerodynamic Tests of Six Airfoils for Use on Small Wind Turbines; Period of Performance: October 31, 2002--January 31, 2003

    SciTech Connect (OSTI)

    Selig, M. S.; McGranahan, B. D.

    2004-10-01T23:59:59.000Z

    Wind Tunnel Aerodynamic Tests of Six Airfoils for Use on Small Wind Turbinesrepresents the fourth installment in a series of volumes documenting the ongoing work of th University of Illinois at Urbana-Champaign Low-Speed Airfoil Tests Program. This particular volume deals with airfoils that are candidates for use on small wind turbines, which operate at low Reynolds numbers.

  14. Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn is converted

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn is converted to electricity. Since wind speeds vary from month to month and second to second, the amount of electricity wind can make varies constantly. Sometimes a wind turbine will make no power at all

  15. 1112 IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 25, NO. 4, DECEMBER 2010 Short-Horizon Prediction of Wind Power

    E-Print Network [OSTI]

    Kusiak, Andrew

    (wind energy in particular) has grown sig- nificantly in the last years. As a relatively new industry, wind energy must address numerous questions, including providing accurate short-term prediction of wind of the generated power [1]. Long-term wind speed and power prediction is of interest to management of energy

  16. Statistical Methods for Quantifying the Effect of the El NioSouthern Oscillation on Wind Power in the

    E-Print Network [OSTI]

    Katz, Richard

    Statistical Methods for Quantifying the Effect of the El Niño­Southern Oscillation on Wind Power­Southern Oscillation on Wind Power in the Northern Great Plains of the United States Bret R. Harper1, Richard W. Katz2 of the United States. In order to determine if ENSO has similar impacts on wind speed and wind power, we applied

  17. Wind power and Wind power and

    E-Print Network [OSTI]

    Wind power and the CDM #12; Wind power and the CDM Emerging practices in developing wind power 2005 Jyoti P. Painuly, Niels-Erik Clausen, Jørgen Fenhann, Sami Kamel and Romeo Pacudan #12; WIND POWER AND THE CDM Emerging practices in developing wind power projects for the Clean Development Mechanism Energy

  18. Use of Slip Ring Induction Generator for Wind Power Generation

    E-Print Network [OSTI]

    K Y Patil; D S Chavan

    Wind energy is now firmly established as a mature technology for electricity generation. There are different types of generators that can be used for wind energy generation, among which Slip ring Induction generator proves to be more advantageous. To analyse application of Slip ring Induction generator for wind power generation, an experimental model is developed and results are studied. As power generation from natural sources is the need today and variable speed wind energy is ample in amount in India, it is necessary to study more beneficial options for wind energy generating techniques. From this need a model is developed by using Slip ring Induction generator which is a type of Asynchronous generator.

  19. Power Performance Test Report for the SWIFT Wind Turbine

    SciTech Connect (OSTI)

    Mendoza, I.; Hur, J.

    2012-12-01T23:59:59.000Z

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

  20. animal high-speed microct: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    occur. Although current ... SooHoo, Kimberly E 2008-01-01 45 High speed air pneumatic wind shield wiping design MIT - DSpace Summary: In this creative design process a number of...

  1. aisi m2 high-speed: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    occur. Although current ... SooHoo, Kimberly E 2008-01-01 44 High speed air pneumatic wind shield wiping design MIT - DSpace Summary: In this creative design process a number of...

  2. Optimization of wind turbine energy and power factor with an evolutionary computation algorithm

    E-Print Network [OSTI]

    Kusiak, Andrew

    -controllable variables of a 1.5 MW wind turbine. An evolutionary strategy algorithm solves the data-derived optimization-linear approach to control a variable-speed turbine to maximize power in the presence of generator torque for variable-speed wind turbines. Munteanu et al. [11] applied a linear-quadratic stochastic approach to solve

  3. Wind Energy Resource Assessment of the Caribbean and Central America

    SciTech Connect (OSTI)

    DL Elliott; CI Aspliden; GL Gower; CG Holladay, MN Schwartz

    1987-04-01T23:59:59.000Z

    A wind energy resource assessment of the Caribbean and Central America has identified many areas with good to outstanding wind resource potential for wind turbine applications. Annual average wind resource maps and summary tables have been developed for 35 island/country areas throughout the Caribbean and Central America region. The wind resource maps highlight the locations of major resource areas and provide estimates of the wind energy resource potential for typical well-exposed sites in these areas. The average energy in the wind flowing in the layer near the ground is expressed as a wind power class: the greater the average wind energy, the higher the wind power class. The summary tables that are included with each of the 35 island/country wind energy maps provide information on the frequency distribution of the wind speeds (expressed as estimates of the Weibull shape factor, k) and seasonal variations in the wind resource for the major wind resource areas identified on the maps. A new wind power class legend has been developed for relating the wind power classes to values of mean wind power density, mean wind speed, and Weibull k. Guidelines are presented on how to adjust these values to various heights above ground for different roughness and terrain characteristics. Information evaluated in preparing the assessment included existing meteorological data from airports and other weather stations, and from ships and buoys in offshore and coastal areas. In addition, new data from recent measurement sites established for wind energy siting studies were obtained for a few areas of the Caribbean. Other types of information evaluated in the assessment were climatological data and maps on winds aloft, surface pressure, air flow, and topography. The various data were screened and evaluated for their usefulness in preparing the wind resource assessment. Much of the surface data from airports and other land-based weather stations were determined to be from sheltered sites and were thus not very useful in assessing the wind resource at locations that are well exposed to the winds. Ship data were determined to be the most useful for estimating the large-scale wind flow and assessing the spatial distribution of the wind resource throughout the region. Techniques were developed for analyzing and correcting ship wind data and extrapolating these data to coastal and inland areas by considering terrain influences on the large-scale wind flow. In areas where extrapolation of ship wind data was not entirely feasible, such as interior areas of Central America, other techniques were developed for estimating the wind flow and distribution of the wind resource. Through the application of the various innovative techniques developed for assessing the wind resource throughout the Caribbean and Central America region, many areas with potentially good to outstanding wind resource were identified that had not been previously recognized. In areas where existing site data were available from exposed locations, the measured wind resource was compared with the estimated wind resource that was derived using the assessment techniques. In most cases, there was good agreement between the measured wind resource and the estimated wind resource. This assessment project supported activities being pursued by the U.S. Committee for Renewable Energy Commerce and Trade (CORECT), the U.S. government's interagency program to assist in overseas marketing and promote renewable energy exports. An overall goal of the program is to improve U.S. competitiveness in the world renewable energy market. The Caribbean and Central America assessment, which is the first of several possible follow-on international wind energy resource assessments, provides valuable information needed by the U.S. wind energy industry to identify suitable wind resource areas and concentrate their efforts on these areas.

  4. Variable diameter wind turbine rotor blades

    DOE Patents [OSTI]

    Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.

    2005-12-06T23:59:59.000Z

    A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.

  5. Wind Power

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhat is abig world of tinyWind Industry SoarsWind

  6. Ris-R-1118(EN) Power Control for Wind Tur-

    E-Print Network [OSTI]

    storage or with an AC/DC converter and battery storage. The AC/DC converter can either be an "add-on" type.3 Wind turbine and wind speed model 24 8.4 Storage models 25 Pumped storage model 25 Battery storage, use of different storage types, development of a framework for comparing different options and tools

  7. Economic assessment of small-scale electricity generation from wind

    E-Print Network [OSTI]

    McAllister, Kristen Dawn

    2007-09-17T23:59:59.000Z

    10 kW wind turbine on a 30m tower was installed and five different scenarios were calculated for both locations. Wind speeds for both locations were collected and analyzed to find the closest fitting distribution to incorporate the appropriate risk...

  8. 66 APRIL | 2010 The FuTure oF Wind Turbine

    E-Print Network [OSTI]

    Kusiak, Andrew

    in the form of large-scale wind farms, wind energy cooperatives, wind turbines owned by indi- vidual investors66 APRIL | 2010 The FuTure oF Wind Turbine diagnosTics Wind energy is undergoing expansion, and multinational exploration of remote sites and offshore locations. Despite the in- creasing rated capacity

  9. Response of a vessel to waves at zero ship speed

    E-Print Network [OSTI]

    Response of a vessel to waves at zero ship speed: preliminary full scale experiments By: Kim Klaka of experiment were conducted ­ free roll decay tests and irregular wave tests. An inclining test was also with and without the mainsail hoisted, in very light winds. The irregular wave tests were conducted again in very

  10. National Wind Technology Center (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-12-01T23:59:59.000Z

    This overview fact sheet is one in a series of information fact sheets for the National Wind Technology Center (NWTC). Wind energy is one of the fastest growing electricity generation sources in the world. NREL's National Wind Technology Center (NWTC), the nation's premier wind energy technology research facility, fosters innovative wind energy technologies in land-based and offshore wind through its research and testing facilities and extends these capabilities to marine hydrokinetic water power. Research and testing conducted at the NWTC offers specialized facilities and personnel and provides technical support critical to the development of advanced wind energy systems. From the base of a system's tower to the tips of its blades, NREL researchers work side-by-side with wind industry partners to increase system reliability and reduce wind energy costs. The NWTC's centrally located research and test facilities at the foot of the Colorado Rockies experience diverse and robust wind patterns ideal for testing. The NWTC tests wind turbine components, complete wind energy systems and prototypes from 400 watts to multiple megawatts in power rating.

  11. Final Technical Report Power through Policy: "Best Practices" for Cost-Effective Distributed Wind

    SciTech Connect (OSTI)

    Rhoads-Weaver, Heather; Gagne, Matthew; Sahl, Kurt; Orrell, Alice; Banks, Jennifer

    2012-02-28T23:59:59.000Z

    Power through Policy: 'Best Practices' for Cost-Effective Distributed Wind is a U.S. Department of Energy (DOE)-funded project to identify distributed wind technology policy best practices and to help policymakers, utilities, advocates, and consumers examine their effectiveness using a pro forma model. Incorporating a customized feed from the Database of State Incentives for Renewables and Efficiency (DSIRE), the Web-based Distributed Wind Policy Comparison Tool (Policy Tool) is designed to assist state, local, and utility officials in understanding the financial impacts of different policy options to help reduce the cost of distributed wind technologies. The project's final products include the Distributed Wind Policy Comparison Tool, found at www.windpolicytool.org, and its accompanying documentation: Distributed Wind Policy Comparison Tool Guidebook: User Instructions, Assumptions, and Case Studies. With only two initial user inputs required, the Policy Tool allows users to adjust and test a wide range of policy-related variables through a user-friendly dashboard interface with slider bars. The Policy Tool is populated with a variety of financial variables, including turbine costs, electricity rates, policies, and financial incentives; economic variables including discount and escalation rates; as well as technical variables that impact electricity production, such as turbine power curves and wind speed. The Policy Tool allows users to change many of the variables, including the policies, to gauge the expected impacts that various policy combinations could have on the cost of energy (COE), net present value (NPV), internal rate of return (IRR), and the simple payback of distributed wind projects ranging in size from 2.4 kilowatts (kW) to 100 kW. The project conducted case studies to demonstrate how the Policy Tool can provide insights into 'what if' scenarios and also allow the current status of incentives to be examined or defended when necessary. The ranking of distributed wind state policy and economic environments summarized in the attached report, based on the Policy Tool's default COE results, highlights favorable market opportunities for distributed wind growth as well as market conditions ripe for improvement. Best practices for distributed wind state policies are identified through an evaluation of their effect on improving the bottom line of project investments. The case studies and state rankings were based on incentives, power curves, and turbine pricing as of 2010, and may not match the current results from the Policy Tool. The Policy Tool can be used to evaluate the ways that a variety of federal and state policies and incentives impact the economics of distributed wind (and subsequently its expected market growth). It also allows policymakers to determine the impact of policy options, addressing market challenges identified in the U.S. DOE's '20% Wind Energy by 2030' report and helping to meet COE targets. In providing a simple and easy-to-use policy comparison tool that estimates financial performance, the Policy Tool and guidebook are expected to enhance market expansion by the small wind industry by increasing and refining the understanding of distributed wind costs, policy best practices, and key market opportunities in all 50 states. This comprehensive overview and customized software to quickly calculate and compare policy scenarios represent a fundamental step in allowing policymakers to see how their decisions impact the bottom line for distributed wind consumers, while estimating the relative advantages of different options available in their policy toolboxes. Interested stakeholders have suggested numerous ways to enhance and expand the initial effort to develop an even more user-friendly Policy Tool and guidebook, including the enhancement and expansion of the current tool, and conducting further analysis. The report and the project's Guidebook include further details on possible next steps. NREL Report No. BK-5500-53127; DOE/GO-102011-3453.

  12. Balancing of high speed, flexible rotating shafts across critical speeds

    E-Print Network [OSTI]

    White, Gary Paul

    1977-01-01T23:59:59.000Z

    this is equivalent to eliminating certain sen- sors. Once the influence coefficient matrix is square, the solution procedure is exactly that of the single speed case. The computed balance weights should now null the rotor vibration at the sensor ports which were... critical speed, The Sin- gle Speed and the Exact Point-Speed techniques were determined to be relatively ineffective over this speed range; however, the Least Squares procedure yields a dramatic decrease in rotor vibration over the entire speed range...

  13. On the Fatigue Analysis of Wind Turbines

    SciTech Connect (OSTI)

    Sutherland, Herbert J.

    1999-06-01T23:59:59.000Z

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

  14. Verification of hourly forecasts of wind turbine power output

    SciTech Connect (OSTI)

    Wegley, H.L.

    1984-08-01T23:59:59.000Z

    A verification of hourly average wind speed forecasts in terms of hourly average power output of a MOD-2 was performed for four sites. Site-specific probabilistic transformation models were developed to transform the forecast and observed hourly average speeds to the percent probability of exceedance of an hourly average power output. (This transformation model also appears to have value in predicting annual energy production for use in wind energy feasibility studies.) The transformed forecasts were verified in a deterministic sense (i.e., as continuous values) and in a probabilistic sense (based upon the probability of power output falling in a specified category). Since the smoothing effects of time averaging are very pronounced, the 90% probability of exceedance was built into the transformation models. Semiobjective and objective (model output statistics) forecasts were made compared for the four sites. The verification results indicate that the correct category can be forecast an average of 75% of the time over a 24-hour period. Accuracy generally decreases with projection time out to approx. 18 hours and then may increase due to the fairly regular diurnal wind patterns that occur at many sites. The ability to forecast the correct power output category increases with increasing power output because occurrences of high hourly average power output (near rated) are relatively rare and are generally not forecast. The semiobjective forecasts proved superior to model output statistics in forecasting high values of power output and in the shorter time frames (1 to 6 hours). However, model output statistics were slightly more accurate at other power output levels and times. Noticeable differences were observed between deterministic and probabilistic (categorical) forecast verification results.

  15. Methods and apparatus for twist bend coupled (TCB) wind turbine blades

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw; LeMieux, David Lawrence; Pierce, Kirk Gee

    2006-10-10T23:59:59.000Z

    A method for controlling a wind turbine having twist bend coupled rotor blades on a rotor mechanically coupled to a generator includes determining a speed of a rotor blade tip of the wind turbine, measuring a current twist distribution and current blade loading, and adjusting a torque of a generator to change the speed of the rotor blade tip to thereby increase an energy capture power coefficient of the wind turbine.

  16. Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms

    E-Print Network [OSTI]

    Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms is not used to supply baseload electric power today. Interconnecting wind farms through the transmission grid farms are interconnected in an array, wind speed correlation among sites decreases and so does

  17. Vibration Analysis of a Vertical Axis Wind Turbine Blade , S.Tullis 2

    E-Print Network [OSTI]

    Tullis, Stephen

    Vibration Analysis of a Vertical Axis Wind Turbine Blade K. Mc Laren 1 , S.Tullis 2 and S.Ziada 3 1 vibration source of a small-scale vertical axis wind turbine currently undergoing field-testing. The turbine at a blade-tip speed ratio (the ratio of the blade rotational velocity to the ambient wind velocity) of 1

  18. Powering Up With Space-Time Wind Forecasting Amanda S. HERING and Marc G. GENTON

    E-Print Network [OSTI]

    Genton, Marc G.

    Powering Up With Space-Time Wind Forecasting Amanda S. HERING and Marc G. GENTON The technology to harvest electricity from wind energy is now advanced enough to make entire cities powered by it a reality be more realistically assessed with a loss measure that depends upon the power curve relating wind speed

  19. Developing a Practical Wind Tunnel Test Engineering Course for Undergraduate Aerospace Engineering Students

    E-Print Network [OSTI]

    Recla, Benjamin Jeremiah

    2013-04-19T23:59:59.000Z

    This thesis describes the development and assessment of an undergraduate wind tunnel test engineering course utilizing the 7ft by 10ft Oran W. Nicks Low Speed Wind Tunnel (LSWT). Only 5 other universities in the United States have a wind tunnel...

  20. Advanced Signal Processing Techniques for Fault Detection and Diagnosis in a Wind Turbine

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    rotor bars and bearing damages. Index Terms--Wind turbines, motor current signature analy- sis, time factors, such as wind speed and acoustic noise, wind parks are being mainly constructed offshore. Studies. Different methods of fault detection exist. These include monitoring of the acoustic vibration, internal