National Library of Energy BETA

Sample records for rated wind speed

  1. LIDAR Wind Speed Measurements of Evolving Wind Fields

    SciTech Connect (OSTI)

    Simley, E.; Pao, L. Y.

    2012-07-01

    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.

  2. File:CV WindSpeed.pdf | Open Energy Information

    Open Energy Info (EERE)

    CV WindSpeed.pdf Jump to: navigation, search File File history File usage Cape Verde-Map Summarizing Average Wind Speed (ms) Size of this preview: 776 600 pixels. Full...

  3. Effectiveness of Changing Wind Turbine Cut-in Speed to Reduce Bat Fatalities at Wind Facilities

    SciTech Connect (OSTI)

    Huso, Manuela M. P.; Hayes, John P.

    2009-04-01

    This report details an experiment on the effectiveness of changing wind turbine cut-in speed on reducing bat fatality from wind turbines at the Casselman Wind Project in Somerset County, Pennsylvania.

  4. Spatial and Temporal Patterns of Global Onshore Wind Speed Distributio...

    Office of Scientific and Technical Information (OSTI)

    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 ...

  5. Dominican Republic - Annual Average Wind Speed at 80 meters

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

    Monte Plata Bonao Elias Pina El Seibo Hato Mayor Higuey Santo Domingo La Romana San Pedro Jimani San Cristobal Azua Neiba Bani Barahona Pedernales Wind Speed ms >10.5 10.0 9.5...

  6. Wind speed power spectrum analysis for Bushland, Texas

    SciTech Connect (OSTI)

    Eggleston, E.D.

    1996-12-31

    Numerous papers and publications on wind turbulence have referenced the wind speed spectrum presented by Isaac Van der Hoven in his article entitled Power Spectrum of Horizontal Wind Speed Spectrum in the Frequency Range from 0.0007 to 900 Cycles per Hour. Van der Hoven used data measured at different heights between 91 and 125 meters above the ground, and represented the high frequency end of the spectrum with data from the peak hour of hurricane Connie. These facts suggest we should question the use of his power spectrum in the wind industry. During the USDA - Agricultural Research Service`s investigation of wind/diesel system power storage, using the appropriate wind speed power spectrum became a significant issue. We developed a power spectrum from 13 years of hourly average data, 1 year of 5 minute average data, and 2 particularly gusty day`s 1 second average data all collected at a height of 10 meters. While the general shape is similar to the Van der Hoven spectrum, few of his peaks were found in the Bushland spectrum. While higher average wind speeds tend to suggest higher amplitudes in the high frequency end of the spectrum, this is not always true. Also, the high frequency end of the spectrum is not accurately described by simple wind statistics such as standard deviation and turbulence intensity. 2 refs., 5 figs., 1 tab.

  7. 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

    2009-01-20

    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.

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

    SciTech Connect (OSTI)

    Robert W. Preus; DOE Project Officer - Keith Bennett

    2008-04-23

    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 Energys (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.

  9. Flutter Speed Predictions for MW-Sized Wind Turbine Blades Don...

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

    Flutter Speed Predictions for MW-Sized Wind Turbine Blades Don W. Lobitz Sandia National ... Leishman, J. G., "Challenges in Modelling the Unsteady Aerodynamics of Wind Turbines," ...

  10. Hi-Q Rotor - Low Wind Speed Technology

    SciTech Connect (OSTI)

    Todd E. Mills; Judy Tatum

    2010-01-11

    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

  11. United States Wind Resource Map: Annual Average Wind Speed at 30 Meters

    Wind Powering America (EERE)

    30 m 21-FEB-2012 2.1.1 Wind Speed m/s >10.5 10.0 9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 < 4.0 Source: Wind resource estimates developed by AWS Truepower, LLC. Web: http://www.awstruepower.com. Map developed by NREL. Spatial resolution of wind resource data: 2.0 km. Projection: Albers Equal Area WGS84. The average wind speeds indicated on this map are model-derived estimates that may not represent the true wind resource at any given location. Small terrain features, vegetation,

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

    Wind Powering America (EERE)

    80 m 01-APR-2011 2.1.1 Wind Speed m/s >10.5 10.0 9.5 9.0 8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 < 4.0 Source: Wind resource estimates developed by AWS Truepower, LLC for windNavigator . Web: http://www.windnavigator.com | http://www.awstruepower.com. Spatial resolution of wind resource data: 2.5 km. Projection: Albers Equal Area WGS84. ¶

  13. File:QuikSCAT - Annual Wind Speed at 10 m.pdf | Open Energy Informatio...

    Open Energy Info (EERE)

    QuikSCAT - Annual Wind Speed at 10 m.pdf Jump to: navigation, search File File history File usage QuikSCAT - Annual Wind Speed at 10 m Size of this preview: 463 599 pixels....

  14. 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.

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

    DOE Patents [OSTI]

    Muljadi, E.

    1998-08-25

    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.

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

    DOE Patents [OSTI]

    Muljadi, Eduard

    1998-01-01

    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.

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

    DOE Patents [OSTI]

    Muljadi, Eduard

    1998-08-25

    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.

  18. Adaptive Pitch Control for Variable Speed Wind Turbines - Energy...

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

    In the early development of wind energy, the majority of wind turbines or wind turbine ... In most cases, wind turbine pitch angles can be adjusted to control the operation of the ...

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

    SciTech Connect (OSTI)

    Mikhail, A.

    2009-01-01

    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.

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

    SciTech Connect (OSTI)

    Genesis Partners LP

    2010-08-01

    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.

  1. 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

    2006-03-01

    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.

  2. 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.

    2005-11-01

    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.

  3. 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.

    2011-10-01

    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

  4. Twin Groves Wind Energy Facility Cut-in Speeds

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Currently, only operational mitigation (stopping turbine blades from spinning) during ... Most studies found at least a 50% reduction in bat fatalities when turbine cut-in speed ...

  5. Variable-Speed Wind Power System with Improved Energy Capture via

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

    Multilevel Conversion - Energy Innovation Portal Wind Energy Wind Energy Electricity Transmission Electricity Transmission Advanced Materials Advanced Materials Find More Like This Return to Search Variable-Speed Wind Power System with Improved Energy Capture via Multilevel Conversion National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary Power converters are used to convert alternating current (AC) electric power from a fixed-frequency and

  6. Haiti - Annual Average Wind Speed at 80 meters

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

    Liberte Hinche 06-JAN-2014 3.5.1 50 0 Port-au-Prince Jacmel Les Cayes Jeremie 50 100 Kilometers DOMINI REPUBL CAN IC The wind resource estimates on this map are from model...

  7. Anemometer Data (Wind Speed, Direction) for Pascua Yaqui, AZ...

    Open Energy Info (EERE)

    from a height of 20 m. The data was originally made available by Wind Powering America, a DOE Office of Energy Efficiency & Renewable Energy (EERE) program. Data and Resources...

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

    SciTech Connect (OSTI)

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

    2012-11-01

    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.

  9. Adaptive pitch control for variable speed wind turbines

    DOE Patents [OSTI]

    Johnson, Kathryn E.; Fingersh, Lee Jay

    2012-05-08

    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.

  10. WIND SPEED AND ATMOSPHERIC STABILITY TRENDS FOR SELECTED UNITED STATES SURFACE STATIONS

    SciTech Connect (OSTI)

    Buckley, R; Allen H. Weber, A

    2006-11-01

    Recently it has been suggested that global warming and a decrease in mean wind speeds over most land masses are related. Decreases in near surface wind speeds have been reported by previous investigators looking at records with time spans of 15 to 30 years. This study focuses on United States (US) surface stations that have little or no location change since the late 1940s or the 1950s--a time range of up to 58 years. Data were selected from 62 stations (24 of which had not changed location) and separated into ten groups for analysis. The group's annual averages of temperature, wind speed, and percentage of Pasquill-Gifford (PG) stability categories were fitted with linear least squares regression lines. The results showed that the temperatures have increased for eight of the ten groups as expected. Wind speeds have decreased for nine of the ten groups. The mean slope of the wind speed trend lines for stations within the coterminous US was -0.77 m s{sup -1} per century. The percentage frequency of occurrence for the neutral (D) PG stability category decreased, while that for the unstable (B) and the stable (F) categories increased in almost all cases except for the group of stations located in Alaska.

  11. Twin Groves Wind Energy Facility Cut-in Speeds

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    SYNTHESIS OF OPERATIONAL MITIGATION STUDIES TO REDUCE BAT FATALITIES AT WIND ENERGY FACILITIES IN NORTH AMERICA Prepared for: The National Renewable Energy Laboratory 15013 Denver West Parkway Golden, CO 80401 Prepared by: Edward B. Arnett 1 , Gregory D. Johnson 2 , Wally P. Erickson 2 , and Cris D. Hein 3 1 Theordore Roosevelt Conservation Partnership 2 Western EcoSystems Technology, Inc. 3 Bat Conservation International March 2013 CITATION Arnett, E. B., G. D. Johnson, W. P. Erickson, and C.

  12. Low Wind Speed Technology Phase II: Integrated Wind Energy/Desalination System; General Electric Global Research

    SciTech Connect (OSTI)

    Not Available

    2006-03-01

    This fact sheet describes a subcontract with General Electric Global Research to explore wind power as a desirable option for integration with desalination technologies.

  13. Influence of wind speed averaging on estimates of dimethylsulfide emission fluxes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chapman, E. G.; Shaw, W. J.; Easter, R. C.; Bian, X.; Ghan, S. J.

    2002-12-03

    The effect of various wind-speed-averaging periods on calculated DMS emission fluxes is quantitatively assessed. Here, a global climate model and an emission flux module were run in stand-alone mode for a full year. Twenty-minute instantaneous surface wind speeds and related variables generated by the climate model were archived, and corresponding 1-hour-, 6-hour-, daily-, and monthly-averaged quantities calculated. These various time-averaged, model-derived quantities were used as inputs in the emission flux module, and DMS emissions were calculated using two expressions for the mass transfer velocity commonly used in atmospheric models. Results indicate that the time period selected for averaging wind speedsmore » can affect the magnitude of calculated DMS emission fluxes. A number of individual marine cells within the global grid show DMS emissions fluxes that are 10-60% higher when emissions are calculated using 20-minute instantaneous model time step winds rather than monthly-averaged wind speeds, and at some locations the differences exceed 200%. Many of these cells are located in the southern hemisphere where anthropogenic sulfur emissions are low and changes in oceanic DMS emissions may significantly affect calculated aerosol concentrations and aerosol radiative forcing.« less

  14. Wind speed response of marine non-precipitating stratocumulus clouds over a diurnal cycle in cloud-system resolving simulations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kazil, Jan; Feingold, Graham; Yamaguchi, Takanobu

    2016-05-12

    Observed and projected trends in large-scale wind speed over the oceans prompt the question: how do marine stratocumulus clouds and their radiative properties respond to changes in large-scale wind speed? Wind speed drives the surface fluxes of sensible heat, moisture, and momentum and thereby acts on cloud liquid water path (LWP) and cloud radiative properties. We present an investigation of the dynamical response of non-precipitating, overcast marine stratocumulus clouds to different wind speeds over the course of a diurnal cycle, all else equal. In cloud-system resolving simulations, we find that higher wind speed leads to faster boundary layer growth and strongermore » entrainment. The dynamical driver is enhanced buoyant production of turbulence kinetic energy (TKE) from latent heat release in cloud updrafts. LWP is enhanced during the night and in the morning at higher wind speed, and more strongly suppressed later in the day. Wind speed hence accentuates the diurnal LWP cycle by expanding the morning–afternoon contrast. The higher LWP at higher wind speed does not, however, enhance cloud top cooling because in clouds with LWP ≳50 gm–2, longwave emissions are insensitive to LWP. This leads to the general conclusion that in sufficiently thick stratocumulus clouds, additional boundary layer growth and entrainment due to a boundary layer moistening arises by stronger production of TKE from latent heat release in cloud updrafts, rather than from enhanced longwave cooling. Here, we find that large-scale wind modulates boundary layer decoupling. At nighttime and at low wind speed during daytime, it enhances decoupling in part by faster boundary layer growth and stronger entrainment and in part because shear from large-scale wind in the sub-cloud layer hinders vertical moisture transport between the surface and cloud base. With increasing wind speed, however, in decoupled daytime conditions, shear-driven circulation due to large-scale wind takes over from

  15. Wind speed response of marine non-precipitating stratocumulus clouds over a diurnal cycle in cloud-system resolving simulations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kazil, Jan; Feingold, Graham; Yamaguchi, Takanobu

    2016-05-12

    Observed and projected trends in large-scale wind speed over the oceans prompt the question: how do marine stratocumulus clouds and their radiative properties respond to changes in large-scale wind speed? Wind speed drives the surface fluxes of sensible heat, moisture, and momentum and thereby acts on cloud liquid water path (LWP) and cloud radiative properties. We present an investigation of the dynamical response of non-precipitating, overcast marine stratocumulus clouds to different wind speeds over the course of a diurnal cycle, all else equal. In cloud-system resolving simulations, we find that higher wind speed leads to faster boundary layer growth and strongermore » entrainment. The dynamical driver is enhanced buoyant production of turbulence kinetic energy (TKE) from latent heat release in cloud updrafts. LWP is enhanced during the night and in the morning at higher wind speed, and more strongly suppressed later in the day. Wind speed hence accentuates the diurnal LWP cycle by expanding the morning–afternoon contrast. The higher LWP at higher wind speed does not, however, enhance cloud top cooling because in clouds with LWP ⪆ 50 g m−2, longwave emissions are insensitive to LWP. This leads to the general conclusion that in sufficiently thick stratocumulus clouds, additional boundary layer growth and entrainment due to a boundary layer moistening arises by stronger production of TKE from latent heat release in cloud updrafts, rather than from enhanced longwave cooling. We find that large-scale wind modulates boundary layer decoupling. At nighttime and at low wind speed during daytime, it enhances decoupling in part by faster boundary layer growth and stronger entrainment and in part because shear from large-scale wind in the sub-cloud layer hinders vertical moisture transport between the surface and cloud base. With increasing wind speed, however, in decoupled daytime conditions, shear-driven circulation due to large-scale wind takes over

  16. Wind speed response of marine non-precipitating stratocumulus clouds over a diurnal cycle in cloud-system resolving simulations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kazil, J.; Feingold, G.; Yamaguchi, T.

    2015-10-21

    Observed and projected trends in large scale wind speed over the oceans prompt the question: how might marine stratocumulus clouds and their radiative properties respond to future changes in large scale wind speed? Wind speed drives the surface fluxes of sensible heat, moisture, and momentum, and thereby acts on cloud liquid water path (LWP) and cloud radiative properties. We present an investigation of the dynamical response of non-precipitating, overcast marine stratocumulus clouds to different wind speeds, all else equal. In cloud-system resolving simulations, we find that higher wind speed leads to faster boundary layer growth and stronger entrainment. The dynamicalmoredriver is enhanced buoyant production of turbulence kinetic energy (TKE) from latent heat release in cloud updrafts. LWP is enhanced during the night and in the morning at higher wind speed, and more strongly suppressed later in the day. Wind speed hence accentuates the diurnal LWP cycle by expanding the morning afternoon contrast. The higher LWP at higher wind speed does not, however, enhance cloud top cooling because in clouds with LWP ⪆ 50 g m?2, long wave emissions are very insensitive to LWP. This leads to the more general conclusion that in sufficiently thick stratocumulus clouds, additional boundary layer growth and entrainment due to a boundary layer moistening arises by stronger production of TKE from latent heat release in cloud updrafts, rather than from enhanced longwave cooling. We find furthermore that large scale wind modulates boundary layer decoupling. At nighttime and at low wind speed during daytime, it enhances decoupling in part by faster boundary layer growth and stronger entrainment, and in part because circulation driven by shear from large scale wind in the sub-cloud layer hinders vertical moisture transport between the surface and cloud base. With increasing wind speed, however, in decoupled daytime conditions, shear-driven circulation due to large scale

  17. 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.

    2011-01-03

    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.

  18. Frequency Regulation and Oscillation Damping Contributions of Variable-Speed Wind Generators in the U.S. Eastern Interconnection (EI)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Liu, Yong; Gracia, Jose R,; King, Jr, Thomas J.; Liu, Yilu

    2014-05-16

    The U.S. Eastern Interconnection (EI) is one of the largest electric power grids in the world and is expected to have difficulties in dealing with frequency regulation and oscillation damping issues caused by the increasing wind power. On the other side, variable-speed wind generators can actively engage in frequency regulation or oscillation damping with supplementary control loops. This paper creates a 5% wind power penetration simulation scenario based on the 16 000-bus EI system dynamic model and developed the user-defined wind electrical control model in PSS (R) E that incorporates additional frequency regulation and oscillation damping control loops. We evaluatedmore » the potential contributions of variable-speed wind generations to the EI system frequency regulation and oscillation damping, and simulation results demonstrate that current and future penetrations of wind power are promising in the EI system frequency regulation and oscillation damping.« less

  19. Frequency Regulation and Oscillation Damping Contributions of Variable-Speed Wind Generators in the U.S. Eastern Interconnection (EI)

    SciTech Connect (OSTI)

    Liu, Yong; Gracia, Jose R,; King, Jr, Thomas J.; Liu, Yilu

    2014-05-16

    The U.S. Eastern Interconnection (EI) is one of the largest electric power grids in the world and is expected to have difficulties in dealing with frequency regulation and oscillation damping issues caused by the increasing wind power. On the other side, variable-speed wind generators can actively engage in frequency regulation or oscillation damping with supplementary control loops. This paper creates a 5% wind power penetration simulation scenario based on the 16 000-bus EI system dynamic model and developed the user-defined wind electrical control model in PSS (R) E that incorporates additional frequency regulation and oscillation damping control loops. We evaluated the potential contributions of variable-speed wind generations to the EI system frequency regulation and oscillation damping, and simulation results demonstrate that current and future penetrations of wind power are promising in the EI system frequency regulation and oscillation damping.

  20. Utility-scale variable-speed wind turbines using a doubly-fed generator with a soft-switching power converter

    SciTech Connect (OSTI)

    Weigand, C.H.; Lauw, H.K.; Marckx, D.A.

    1996-12-31

    Utility-scale wind turbines operating at variable RPM have been studied for a considerable period of time. Whereas the increase in energy output originally has been considered the principal benefit of variable-speed operation, the ability to tightly control the drive-train torque by electronic means is becoming another very important cost factor, especially for turbine ratings above 500 kilowatts. This cost benefit becomes even more significant as optimum turbine ratings today are approaching (and surpassing) 1 Megawatt. Having identified the benefits for the turbine, the designer is confronted with the task of finding the most cost-effective variable-speed generation system which allows him to make use of the benefits, yet does not introduce well-known electrical problems associated with state-of-the-art variable-speed generator controls, such as drastically reduced generator winding life, excessive harmonics on the utility, and poor utility power factor. This paper will indicate that for high-power (> 500 kW), utility-scale wind turbines a doubly-fed generator system in connection with a soft-switching resonant power converter is the least-cost variable-speed generation system offering all of the desired benefits, yet avoids the introduction of the potential electrical problems stated above. 3 refs., 3 figs., 1 tab.

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

    SciTech Connect (OSTI)

    Clark, E.L.

    1994-07-01

    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.

  2. 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.

    2014-10-01

    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.

  3. Wind Issues in Solar Thermal Performance Ratings: Preprint

    SciTech Connect (OSTI)

    Burch, J.; Casey, R.

    2009-04-01

    We suggest that wind bias against unglazed solar water heaters be mitigated by using a calibrated collector model to derive a wind correction to the measured efficiency curve.

  4. Prediction and analysis of infra and low-frequency noise of upwind horizontal axis wind turbine using statistical wind speed model

    SciTech Connect (OSTI)

    Lee, Gwang-Se; Cheong, Cheolung

    2014-12-15

    Despite increasing concern about low-frequency noise of modern large horizontal-axis wind turbines (HAWTs), few studies have focused on its origin or its prediction methods. In this paper, infra- and low-frequency (the ILF) wind turbine noise are closely examined and an efficient method is developed for its prediction. Although most previous studies have assumed that the ILF noise consists primarily of blade passing frequency (BPF) noise components, these tonal noise components are seldom identified in the measured noise spectrum, except for the case of downwind wind turbines. In reality, since modern HAWTs are very large, during rotation, a single blade of the turbine experiences inflow with variation in wind speed in time as well as in space, breaking periodic perturbations of the BPF. Consequently, this transforms acoustic contributions at the BPF harmonics into broadband noise components. In this study, the ILF noise of wind turbines is predicted by combining Lowson’s acoustic analogy with the stochastic wind model, which is employed to reproduce realistic wind speed conditions. In order to predict the effects of these wind conditions on pressure variation on the blade surface, unsteadiness in the incident wind speed is incorporated into the XFOIL code by varying incident flow velocities on each blade section, which depend on the azimuthal locations of the rotating blade. The calculated surface pressure distribution is subsequently used to predict acoustic pressure at an observing location by using Lowson’s analogy. These predictions are compared with measured data, which ensures that the present method can reproduce the broadband characteristics of the measured low-frequency noise spectrum. Further investigations are carried out to characterize the IFL noise in terms of pressure loading on blade surface, narrow-band noise spectrum and noise maps around the turbine.

  5. Solar wind stream interaction: Electron temperature and heat flux rise in the low-speed stream

    SciTech Connect (OSTI)

    Alexander, P.; Duhau, S. )

    1990-11-01

    The strong compression produced in two-stream interaction regions in the solar wind is a local source of heating. The study of the distribution of that energy between heat and internal energy provides valuable information about transport processes. In the present work, the electron heat flux and temperature rise in the compression produced within the low-speed portion of the interaction region is predicted using a new heat conduction law valid for collisionless plasmas with isotropic electron temperature, introduced recently by one of the authors. Equations are found for the electron heat flux and temperature rise as functions of two parameters, one related to the strength of the compression and the other one to the heat flux at the boundaries of the region under study. These equations lead to agreement between theory and experiment.

  6. IEA Wind Task 34 (WREN) Quarterly Webinar #3: Understanding Avian Collision Rate Modeling

    Broader source: Energy.gov [DOE]

    Wind farms can impact birds through collisions. Collision rate models have been developed to estimate the perceived risk to birds and the potential number of collisions within proposed wind farms....

  7. Low Wind Speed Technology Phase II: Offshore Floating Wind Turbine Concepts: Fully Coupled Dynamic Response Simulations; Massachusetts Institute of Technology

    SciTech Connect (OSTI)

    Not Available

    2006-03-01

    This fact sheet describes a subcontract with Massachusetts Institute of Technology to study dynamic response simulations to evaluate floating platform concepts for offshore wind turbines.

  8. Variable-Speed Wind Power Plant Operating With Reserve Power Capability: Preprint

    SciTech Connect (OSTI)

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

    2013-10-01

    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. Wind turbine generators with this capability can support the frequency stability of the grid. To provide governorresponse, wind turbines should be able to generate less power than the available wind power and hold the rest in reserves, ready to be accessed as needed. In this paper, we explore several ways to control wind turbine output to enable reserve-holding capability. The focus of this paper is on doubly-fed induction generator (also known as Type 3) and full-converter (also known as Type 4) windturbines.

  9. Technology Improvement Opportunities for Low Wind Speed Turbines and Implications for Cost of Energy Reduction

    SciTech Connect (OSTI)

    None

    2008-02-01

    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.

  10. MHK ISDB/Sensors/Wind Speed Sensor 2740 | Open Energy Information

    Open Energy Info (EERE)

    Velocity Planar Measurement (Current), 3D Velocity Volumetric Measurement (Current), Density (Ice), Direction (Ice), Speed (Ice), Thickness (Ice), Pressure (Tidal), Sea Surface...

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

    SciTech Connect (OSTI)

    Ligotke, M.W.

    1993-02-01

    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.

  12. Application of Ensemble Sensitivity Analysis to Observation Targeting for Short-term Wind Speed Forecasting

    SciTech Connect (OSTI)

    Zack, J; Natenberg, E; Young, S; Manobianco, J; Kamath, C

    2010-02-21

    The operators of electrical grids, sometimes referred to as Balancing Authorities (BA), typically make critical decisions on how to most reliably and economically balance electrical load and generation in time frames ranging from a few minutes to six hours ahead. At higher levels of wind power generation, there is an increasing need to improve the accuracy of 0- to 6-hour ahead wind power forecasts. Forecasts on this time scale have typically been strongly dependent on short-term trends indicated by the time series of power production and meteorological data from a wind farm. Additional input information is often available from the output of Numerical Weather Prediction (NWP) models and occasionally from off-site meteorological towers in the region surrounding the wind generation facility. A widely proposed approach to improve short-term forecasts is the deployment of off-site meteorological towers at locations upstream from the wind generation facility in order to sense approaching wind perturbations. While conceptually appealing, it turns out that, in practice, it is often very difficult to derive significant benefit in forecast performance from this approach. The difficulty is rooted in the fact that the type, scale, and amplitude of the processes controlling wind variability at a site change from day to day if not from hour to hour. Thus, a location that provides some useful forecast information for one time may not be a useful predictor a few hours later. Indeed, some processes that cause significant changes in wind power production operate predominantly in the vertical direction and thus cannot be monitored by employing a network of sensors at off-site locations. Hence, it is very challenging to determine the type of sensors and deployment locations to get the most benefit for a specific short-term forecast application. Two tools recently developed in the meteorological research community have the potential to help determine the locations and parameters to

  13. NREL: Wind Research - Offshore Wind Resource Characterization

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

    Wind Resource Characterization Map of the United States, showing the wind potential of offshore areas across the country. Enlarge image US offshore wind speed estimates at 90-m ...

  14. 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

    2005-05-31

    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.

  15. Wind Simulation

    Energy Science and Technology Software Center (OSTI)

    2008-12-31

    The Software consists of a spreadsheet written in Microsoft Excel that provides an hourly simulation of a wind energy system, which includes a calculation of wind turbine output as a power-curve fit of wind speed.

  16. Wind Measurements from Arc Scans with Doppler Wind Lidar

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, H.; Barthelmie, R. J.; Clifton, Andy; Pryor, S. C.

    2015-11-25

    When defining optimal scanning geometries for scanning lidars for wind energy applications, we found that it is still an active field of research. Our paper evaluates uncertainties associated with arc scan geometries and presents recommendations regarding optimal configurations in the atmospheric boundary layer. The analysis is based on arc scan data from a Doppler wind lidar with one elevation angle and seven azimuth angles spanning 30° and focuses on an estimation of 10-min mean wind speed and direction. When flow is horizontally uniform, this approach can provide accurate wind measurements required for wind resource assessments in part because of itsmore » high resampling rate. Retrieved wind velocities at a single range gate exhibit good correlation to data from a sonic anemometer on a nearby meteorological tower, and vertical profiles of horizontal wind speed, though derived from range gates located on a conical surface, match those measured by mast-mounted cup anemometers. Uncertainties in the retrieved wind velocity are related to high turbulent wind fluctuation and an inhomogeneous horizontal wind field. Moreover, the radial velocity variance is found to be a robust measure of the uncertainty of the retrieved wind speed because of its relationship to turbulence properties. It is further shown that the standard error of wind speed estimates can be minimized by increasing the azimuthal range beyond 30° and using five to seven azimuth angles.« less

  17. Wind Measurements from Arc Scans with Doppler Wind Lidar

    SciTech Connect (OSTI)

    Wang, H.; Barthelmie, R. J.; Clifton, Andy; Pryor, S. C.

    2015-11-25

    When defining optimal scanning geometries for scanning lidars for wind energy applications, we found that it is still an active field of research. Our paper evaluates uncertainties associated with arc scan geometries and presents recommendations regarding optimal configurations in the atmospheric boundary layer. The analysis is based on arc scan data from a Doppler wind lidar with one elevation angle and seven azimuth angles spanning 30° and focuses on an estimation of 10-min mean wind speed and direction. When flow is horizontally uniform, this approach can provide accurate wind measurements required for wind resource assessments in part because of its high resampling rate. Retrieved wind velocities at a single range gate exhibit good correlation to data from a sonic anemometer on a nearby meteorological tower, and vertical profiles of horizontal wind speed, though derived from range gates located on a conical surface, match those measured by mast-mounted cup anemometers. Uncertainties in the retrieved wind velocity are related to high turbulent wind fluctuation and an inhomogeneous horizontal wind field. Moreover, the radial velocity variance is found to be a robust measure of the uncertainty of the retrieved wind speed because of its relationship to turbulence properties. It is further shown that the standard error of wind speed estimates can be minimized by increasing the azimuthal range beyond 30° and using five to seven azimuth angles.

  18. Simulation of winds as seen by a rotating vertical axis wind turbine blade

    SciTech Connect (OSTI)

    George, R.L.

    1984-02-01

    The objective of this report is to provide turbulent wind analyses relevant to the design and testing of Vertical Axis Wind Turbines (VAWT). A technique was developed for utilizing high-speed turbulence wind data from a line of seven anemometers at a single level to simulate the wind seen by a rotating VAWT blade. Twelve data cases, representing a range of wind speeds and stability classes, were selected from the large volume of data available from the Clayton, New Mexico, Vertical Plane Array (VPA) project. Simulations were run of the rotationally sampled wind speed relative to the earth, as well as the tangential and radial wind speeds, which are relative to the rotating wind turbine blade. Spectral analysis is used to compare and assess wind simulations from the different wind regimes, as well as from alternate wind measurement techniques. The variance in the wind speed at frequencies at or above the blade rotation rate is computed for all cases, and is used to quantitatively compare the VAWT simulations with Horizontal Axis Wind Turbine (HAWT) simulations. Qualitative comparisons are also made with direct wind measurements from a VAWT blade.

  19. 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

    2014-08-01

    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.

  20. Wind Spires as an Alternative Energy Source

    SciTech Connect (OSTI)

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

    2012-10-30

    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).

  1. 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

    2007-07-31

    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.

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

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw; Pierce, Kirk Gee

    2006-10-17

    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. File:Calabarzon Speed 100m | Open Energy Information

    Open Energy Info (EERE)

    Calabarzon - Republic of the Philippines Wind Speed at 100 meters Sources National Renewable Energy Laboratory Authors Billy Roberts Related Technologies Wind, Wind 100m...

  4. Soil erosion rates from mixed soil and gravel surfaces in a wind tunnel

    SciTech Connect (OSTI)

    Ligotke, M.W.; Klopfer, D.C.

    1990-08-01

    Protective barriers have been identified as integral components of plans to isolate defense waste on the Hanford Site. The use of natural materials to construct protective barriers over waste site is being considered. Design requirements for protective barriers include preventing exposure of buried waste, and restricting penetration or percolation of surface waters through the waste zone. Studies were initiated to evaluate the effects of wind erosion on candidate protective barrier surfaces. A wind tunnel was used to provide controlled erosive stresses and to investigate the erosive effects of wind forces on proposed surface layers for protective barriers. Mixed soil and gravel surfaces were prepared and tested for resistance to wind erosion at the Pacific Northwest Laboratory Aerosol Wind Tunnel Research Facility. These tests were performed to investigate surface deflation caused by suspension of soil from various surface layer configurations and to provide a comparison of the relative resistance of the different surfaces to wind erosion. Planning, testing, and analyzing phases of this wind erosion project were coordinated with other tasks supporting the development of protective barriers. These tasks include climate-change predictions, field studies and modeling efforts. This report provides results of measurements of deflation caused by wind forces over level surfaces. Section 2.0 reviews surface layer characteristics and previous relevant studies on wind erosion, describes effects of erosion, and discusses wind tunnel modeling. Materials and methods of the wind tunnel tests are discussed in Section 3.0. Results and discussion are presented in Section 4.0, and conclusions and recommendations Section 5.0. 53 refs., 29 figs., 7 tabs.

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

    SciTech Connect (OSTI)

    Clifton, A.

    2012-12-01

    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.

  6. Preliminary analysis of the audible noise of constant-speed, horizontal-axis wind-turbine generators

    SciTech Connect (OSTI)

    Keast, D. N.; Potter, R. C.

    1980-07-01

    An analytical procedure has been developed for calculating certain aerodynamic sound levels produced by large, horizontal-axis wind-turbine generators (WTG's) such as the DOE/NASA Mods-0, -0A, -1, and -2. This preliminary procedure is based upon very limited field data from the Mod-0. It postulates a noise component due to the (constant) rotation of the blades of the WTG, plus a wake-noise component that increases with the square of the power produced by the WTG. Mechanical sound from machinery, and low-frequency impulsive sounds produced by blade interaction with the wake of the support tower are not considered.

  7. Wind Gallery | Department of Energy

    Office of Environmental Management (EM)

    Supports the structure of the turbine. Because wind speed increases with height, taller ... Measures wind direction and communicates with the yaw drive to orient the turbine properly ...

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

    SciTech Connect (OSTI)

    Bluestein, H.B. . School of Meteorology); Unruh, W.P. )

    1991-01-01

    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.

  9. Wind/Hybrid Electricity Applications

    SciTech Connect (OSTI)

    McDaniel, Lori

    2001-03-31

    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.

  10. Eastern Wind Integration Data Set | Grid Modernization | NREL

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

    Wind power plant locations were determined using a proprietary AWS Truepower wind speed ... The wind speed and power output time series for each wind power plant were computed by ...

  11. 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.

  12. 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.

    2008-02-01

    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.

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

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    new turbines, particularly for offshore wind-helping to speed deployment of next ... conduct research on stronger, more durable wind drivetrains for land-based wind farms. ...

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

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    new turbines, particularly for offshore wind - helping to speed deployment of next ... conduct research on stronger, more durable wind drivetrains for land-based wind farms. ...

  15. Key Activities in Wind Energy | Department of Energy

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

    help communities weigh the benefits and costs of wind energy, understand the deployment ... to electricity supply and demand, wind forecasting, and wind speed variability Develop ...

  16. Wind turbine

    DOE Patents [OSTI]

    Cheney, Jr., Marvin C.

    1982-01-01

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

  17. Distributed Wind Diffusion Model Overview (Presentation)

    SciTech Connect (OSTI)

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

    2014-07-01

    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.

  18. NREL-International Wind Resource Maps | Open Energy Information

    Open Energy Info (EERE)

    Shenyang 50m Wind Power China Tianjin 50m Wind Power China Yinchuan 50m Wind Power East China Map Reference Eastern Visayas Philippines Wind Speed 100m-01 NREL-30m-US-Wind...

  19. Wind energy conversion system

    DOE Patents [OSTI]

    Longrigg, Paul

    1987-01-01

    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.

  20. ARM - Wind Chill Calculations

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

    CalculatorsWind Chill Calculations Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Wind Chill Calculations Wind Chill is the apparent temperature felt on the exposed human body owing to the combination of temperature and wind speed. From 1945 to 2001, Wind Chill was calculated by the Siple

  1. 2014 Wind Technologies Market Report

    SciTech Connect (OSTI)

    Wiser, R.; Bolinger, M.

    2015-08-01

    According to the 2014 Wind Technologies Market Report, total installed wind power capacity in the United States grew at a rate of eight percent in 2014, bringing the United States total installed capacity to nearly 66 gigawatts (GW), which ranks second in the world and meets 4.9 percent of U.S. end-use electricity demand in an average year. In total, 4,854 MW of new wind energy capacity were installed in the United States in 2014. The 2014 Wind Technologies Market Report also finds that wind energy prices are at an all-time low and are competitive with wholesale power prices and traditional power sources across many areas of the United States. Additionally, a new trend identified by the 2014 Wind Technologies Market Report shows utility-scale turbines with larger rotors designed for lower wind speeds have been increasingly deployed across the country in 2014. The findings also suggest that the success of the U.S. wind industry has had a ripple effect on the American economy, supporting 73,000 jobs related to development, siting, manufacturing, transportation, and other industries.

  2. Nebraska wind resource assessment first year results

    SciTech Connect (OSTI)

    Hurley, P.J.F.; Vilhauer, R.; Stooksbury, D.

    1996-12-31

    This paper presents the preliminary results from a wind resource assessment program in Nebraska sponsored by the Nebraska Power Association. During the first year the measured annual wind speed at 40 meters ranged from 6.5 - 7.5 m/s (14.6 - 16.8 mph) at eight stations across the state. The site selection process is discussed as well as an overview of the site characteristics at the monitoring locations. Results from the first year monitoring period including data recovery rate, directionality, average wind speeds, wind shear, and turbulence intensity are presented. Results from the eight sites are qualitatively compared with other midwest and west coast locations. 5 figs., 2 tabs.

  3. Dissipation of turbulence in the wake of a wind turbine

    SciTech Connect (OSTI)

    Lundquist, J. K.; Bariteau, L.

    2014-11-06

    The wake of a wind turbine is characterized by increased turbulence and decreased wind speed. Turbines are generally deployed in large groups in wind farms, and so the behaviour of an individual wake as it merges with other wakes and propagates downwind is critical in assessing wind-farm power production. This evolution depends on the rate of turbulence dissipation in the wind-turbine wake, which has not been previously quantified in field-scale measurements. In situ measurements of winds and turbulence dissipation from the wake region of a multi-MW turbine were collected using a tethered lifting system (TLS) carrying a payload of high-rate turbulence probes. Ambient flow measurements were provided from sonic anemometers on a meteorological tower located near the turbine. Good agreement between the tower measurements and the TLS measurements was established for a case without a wind-turbine wake. When an operating wind turbine is located between the tower and the TLS so that the wake propagates to the TLS, the TLS measures dissipation rates one to two orders of magnitude higher in the wake than outside of the wake. These data, collected between two and three rotor diameters D downwind of the turbine, document the significant enhancement of turbulent kinetic energy dissipation rate within the wind-turbine wake. These wake measurements suggest that it may be useful to pursue modelling approaches that account for enhanced dissipation. Furthermore. comparisons of wake and non-wake dissipation rates to mean wind speed, wind-speed variance, and turbulence intensity are presented to facilitate the inclusion of these measurements in wake modelling schemes.

  4. An Exploration of Wind Energy & Wind Turbines

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    This unit, which includes both a pre and post test on wind power engages students by allowing them to explore connections between wind energy and other forms of energy. Students learn about and examine the overall design of a wind turbine and then move forward with an assessment of the energy output as factors involving wind speed, direction and blade design are altered. Students are directed to work in teams to design, test and analyze components of a wind turbine such as blade length, blade shape, height of turbine, etc Student worksheets are included to facilitate the design and analysis process. Learning Goals: Below are the learning targets for the wind energy unit.

  5. WINDExchange: Where Is Wind Power?

    Wind Powering America (EERE)

    Where Is Wind Power? WINDExchange offers maps to help you visualize the wind resource at a local level and to show how much wind power has been installed in the United States. How much wind power is on my land? Go to the wind resource maps. Go to the wind resource maps. Go to the wind resource maps. If you want to know how much wind power is in a particular area, these wind resource maps can give you a visual indication of the average wind speeds to a local level such as a neighborhood. These

  6. Your wind driven generator

    SciTech Connect (OSTI)

    Wolff, B.

    1984-01-01

    Wind energy pioneer Benjamin Lee Wolff offers practical guidance on all aspects of setting up and operating a wind machine. Potential builders will learn how to: determine if wind energy is suitable for a specific application; choose an appropriate machine; assess the financial costs and benefits of wind energy; obtain necessary permits; sell power to local utilities; and interpret a generator's specifications. Coverage includes legislation, regulations, siting, and operation. While describing wind energy characteristics, Wolff explores the relationships among wind speed, rotor diameter, and electrical power capacity. He shows how the power of wind energy can be tapped at the lowest cost.

  7. Field Testing of LIDAR-Assisted Feedforward Control Algorithms for Improved Speed Control and Fatigue Load Reduction on a 600-kW Wind Turbine: Preprint

    SciTech Connect (OSTI)

    Kumar, Avishek A.; Bossanyi, Ervin A.; Scholbrock, Andrew K.; Fleming, Paul; Boquet, Mathieu; Krishnamurthy, Raghu

    2015-12-14

    A severe challenge in controlling wind turbines is ensuring controller performance in the presence of a stochastic and unknown wind field, relying on the response of the turbine to generate control actions. Recent technologies such as LIDAR, allow sensing of the wind field before it reaches the rotor. In this work a field-testing campaign to test LIDAR Assisted Control (LAC) has been undertaken on a 600-kW turbine using a fixed, five-beam LIDAR system. The campaign compared the performance of a baseline controller to four LACs with progressively lower levels of feedback using 35 hours of collected data.

  8. Eastern Wind Integration and Transmission Study: Executive Summary...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... the weather of historical years and generate a four-dimensional gridded wind-speed data set. A wind speed time series data set can be extracted and converted to wind power output. ...

  9. Dissipation of turbulence in the wake of a wind turbine

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lundquist, J. K.; Bariteau, L.

    2014-11-06

    The wake of a wind turbine is characterized by increased turbulence and decreased wind speed. Turbines are generally deployed in large groups in wind farms, and so the behaviour of an individual wake as it merges with other wakes and propagates downwind is critical in assessing wind-farm power production. This evolution depends on the rate of turbulence dissipation in the wind-turbine wake, which has not been previously quantified in field-scale measurements. In situ measurements of winds and turbulence dissipation from the wake region of a multi-MW turbine were collected using a tethered lifting system (TLS) carrying a payload of high-ratemore » turbulence probes. Ambient flow measurements were provided from sonic anemometers on a meteorological tower located near the turbine. Good agreement between the tower measurements and the TLS measurements was established for a case without a wind-turbine wake. When an operating wind turbine is located between the tower and the TLS so that the wake propagates to the TLS, the TLS measures dissipation rates one to two orders of magnitude higher in the wake than outside of the wake. These data, collected between two and three rotor diameters D downwind of the turbine, document the significant enhancement of turbulent kinetic energy dissipation rate within the wind-turbine wake. These wake measurements suggest that it may be useful to pursue modelling approaches that account for enhanced dissipation. Furthermore. comparisons of wake and non-wake dissipation rates to mean wind speed, wind-speed variance, and turbulence intensity are presented to facilitate the inclusion of these measurements in wake modelling schemes.« less

  10. Coastal Ohio Wind Project

    SciTech Connect (OSTI)

    Gorsevski, Peter; Afjeh, Abdollah; Jamali, Mohsin; Bingman, Verner

    2014-04-04

    to collect additional monitoring parameters such as passage rates, flight paths, flight directions, and flight altitudes of nocturnal migrating species. Our work focused on the design and development of custom built marine radar that used t-bar and parabolic dish antennas. The marine radar used in the project was Furuno (XANK250) which was coupled with a XIR3000B digitizing card from Russell Technologies for collection of the radar data. The radar data was processed by open source radR processing software using different computational techniques and methods. Additional data from thermal IR imaging cameras were collected to detect heat emitted from objects and provide information on movements of birds and bats, data which we used for different animal flight behavior analysis. Lastly, the data from the acoustic recorders were used to provide the number of bird calls for assessing patterns and peak passage rates during migration. The development of the geospatial database included collection of different data sources that are used to support offshore wind turbine development. Many different data sets were collected and organized using initial version of web-based repository software tools that can accommodate distribution of rectified pertinent data sets such as the lake depth, lake bottom engineering parameters, extent of ice, navigation pathways, wind speed, important bird habitats, fish efforts and other layers that are relevant for supporting robust offshore wind turbine developments. Additional geospatial products developed during the project included few different prototypes for offshore wind farm suitability which can involve different stakeholders and participants for solving complex planning problems and building consensus. Some of the prototypes include spatial decision support system (SDSS) for collaborative decision making, a web-based Participatory Geographic Information System (PGIS) framework for evaluating importance of different decision alternatives

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

    SciTech Connect (OSTI)

    Robichaud, R.

    2014-09-01

    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.

  12. See the Wind

    Office of Energy Efficiency and Renewable Energy (EERE)

    The goal of this activity is to help students see the difference in the speed and smoothness of the wind at different altitudes above the earth. This is important for wind engineers as they seek to place their wind turbines in the fastest and smoothest winds possible. It is also a major reason that wind turbines are getting larger and higher in the sky, and is why we are starting to see wind turbines in the plains and out in the ocean near the coast. Teacher background and assessment sheets are provided.

  13. NREL: Wind Research - NREL's WIND Toolkit Provides the Data Needed...

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

    by the numerical model. Barometric pressure, wind speed and direction (at 100 m above ground level), relative humidity, temperature, and air density data are available via an...

  14. The Effect of Steady Winds on Radon-222 Entry from soil into houses

    SciTech Connect (OSTI)

    Riley, W.J.; Gadgil, A.J.; Bonnefous, Y.C.; Nazaroff, W.W.

    1994-10-01

    Wind affects the radon-222 entry rate from soil into buildings and the resulting indoor concentrations. To investigate this phenomenon, we employ a previously tested three-dimensional numerical model of soil-gas Bow around houses, a commercial computational fluid dynamics code, an established model for determining ventilation rates in the presence of wind, and new wind tunnel results for the ground-surface pressure field caused by wind. These tools and data, applied under steady-state conditions to a prototypical residential building, allow us (1) to determine the complex soil-gas flow patterns that result from the presence of wind-generated ground-surface pressures, (2) to evaluate the effect of these flows on the radon concentration in the soil, and (3) to calculate the effect of wind on the radon entry rate and indoor concentration. For a broad range of soil permeabilities, two wind speeds, and two wind directions, we quantify the"flushing" effect of wind on the radon in the soil surrounding a house, and the consequent sharp decrease in radon entry rates. Experimental measurements of the time-dependent radon concentration in soil gas beneath houses confirm the existence of wind-induced flushing. Comparisons are made to modeling predictions obtained while ignoring the effect of the wind-generated ground-surface pressures. These investigations lead to the conclusion that wind-generated ground-surface pressures play a significant role in determining radon entry rates into residential buildings. [References: 26

  15. Doppler Lidar Wind Value-Added Product (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Wind Value-Added Product Citation Details In-Document Search Title: Doppler Lidar Wind Value-Added Product Wind speed and direction, together with pressure, temperature, and ...

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

    SciTech Connect (OSTI)

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

    2014-01-01

    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.

  17. Results from utility wind resource assessment programs in Nebraska, Colorado, and Arizona

    SciTech Connect (OSTI)

    Drapeau, C.L.

    1997-12-31

    Global Energy Concepts (GEC) has been retained by utilities in Colorado, Nebraska, and Arizona to site, install, and operate 21 wind monitoring stations as part of the Utility Wind Resource Assessment Program (U*WRAP). Preliminary results indicate wind speed averages at 40 meters (132 ft) of 6.5 - 7.4 m/s (14.5-16.5 mph) in Nebraska and 7.6 - 8.9 m/s (17.0-19.9 mph) in Colorado. The Arizona stations are not yet operational. This paper presents the history and current status of the 21 monitoring stations as well as preliminary data results. Information on wind speeds, wind direction, turbulence intensity, wind shear, frequency distribution, and data recovery rates are provided.

  18. Analysis of Precipitation (Rain and Snow) Levels and Straight-line Wind Speeds in Support of the 10-year Natural Phenomena Hazards Review for Los Alamos National Laboratory

    SciTech Connect (OSTI)

    Kelly, Elizabeth J.; Dewart, Jean Marie; Deola, Regina

    2015-12-10

    This report provides site-specific return level analyses for rain, snow, and straight-line wind extreme events. These analyses are in support of the 10-year review plan for the assessment of meteorological natural phenomena hazards at Los Alamos National Laboratory (LANL). These analyses follow guidance from Department of Energy, DOE Standard, Natural Phenomena Hazards Analysis and Design Criteria for DOE Facilities (DOE-STD-1020-2012), Nuclear Regulatory Commission Standard Review Plan (NUREG-0800, 2007) and ANSI/ ANS-2.3-2011, Estimating Tornado, Hurricane, and Extreme Straight-Line Wind Characteristics at Nuclear Facility Sites. LANL precipitation and snow level data have been collected since 1910, although not all years are complete. In this report the results from the more recent data (1990–2014) are compared to those of past analyses and a 2004 National Oceanographic and Atmospheric Administration report. Given the many differences in the data sets used in these different analyses, the lack of statistically significant differences in return level estimates increases confidence in the data and in the modeling and analysis approach.

  19. Assessment of Offshore Wind Energy Resources for the United States

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... 50 nm of shore. ...... 69 Table B15. New Hampshire offshore wind resource by wind speed interval, water depth and distance from shore ...

  20. Wind Turbine Blade Design | GE Global Research

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

    Resource Assessment and Characterization Wind Resource Assessment and Characterization A crucial factor in the development, siting, and operation of a wind farm is the ability to assess and characterize available wind resources. The Wind Program supports efforts to accurately define, measure, and forecast the nation's land-based and offshore wind resources. More accurate prediction and measurement of wind speed and direction allow wind farms to supply clean, renewable power to businesses and

  1. Wind Development on Tribal Lands

    SciTech Connect (OSTI)

    Ken Haukaas; Dale Osborn; Belvin Pete

    2008-01-18

    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.

  2. Renaissance for wind power

    SciTech Connect (OSTI)

    Flavin, C.

    1981-10-01

    Wind research and development during the 1970s and recent studies showing wind to be a feasible source of both electrical and mechanical power are behind the rapid expansion of wind energy. Improved technology should make wind energy economical in most countries having sufficient wind and appropriate needs. A form of solar energy, winds form a large pattern of global air circulation because the earth's rotation causes differences in pressure and oceans cause differences in temperature. New development in the ancient art of windmill making date to the 1973 oil embargo, but wind availability must be determined at local sites to determine feasibility. Whether design features of the new technology and the concept of large wind farms will be incorporated in national energy policies will depend on changing attitudes, acceptance by utilities, and the speed with which new information is developed and disseminated. 44 references, 6 figures. (DCK)

  3. Wind Turbine Blade Design

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    Blade engineering and design is one of the most complicated and important aspects of modern wind turbine technology. Engineers strive to design blades that extract as much energy from the wind as possible throughout a range of wind speeds and gusts, yet are still durable, quiet and cheap. A variety of ideas for building turbines and teacher handouts are included in this document and at the Web site.

  4. ARM - Measurement - Horizontal wind

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

    govMeasurementsHorizontal wind ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Horizontal wind The horizontal wind in terms of either speed and direction, or the zonal (u) and meridional (v) components. Categories Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a

  5. Wind Generation on Winnebago Tribal Lands

    SciTech Connect (OSTI)

    Multiple

    2009-09-30

    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

  6. Methods and apparatus for reducing peak wind turbine loads

    DOE Patents [OSTI]

    Moroz, Emilian Mieczyslaw

    2007-02-13

    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.

  7. Wind Resource Assessment of Gujarat (India)

    SciTech Connect (OSTI)

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

    2014-07-01

    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.

  8. THIRD MOMENTS AND THE ROLE OF ANISOTROPY FROM VELOCITY SHEAR IN THE SOLAR WIND

    SciTech Connect (OSTI)

    Stawarz, Joshua E.; Vasquez, Bernard J.; Smith, Charles W.; Forman, Miriam A.; Klewicki, Joseph E-mail: Bernie.Vasquez@unh.edu E-mail: Miriam.Forman@sunysb.edu

    2011-07-20

    We have extended the recent analyses of magnetohydrodynamic third moments as they relate to the turbulent energy cascade in the solar wind to consider the effects of large-scale shear flows. Moments from a large set of Advanced Composition Explorer data have been taken, and chosen data intervals are characterized by the rate of change in the solar wind speed. Mean dissipation rates are obtained in accordance with the predictions of homogeneous shear-driven turbulence. Agreement with predictions is best made for rarefaction intervals where the solar wind speed is decreasing with time. For decreasing speed intervals, we find that the dissipation rates increase with increasing shear magnitude and that the shear-induced fluctuation anisotropy is consistent with a relatively small amount.

  9. Poster Thur Eve 36: Implementation of constant dose rate and gantry speed arc therapy(CDR-CAS-IMAT) for thoracic esophageal carcinoma on Varian 23EX

    SciTech Connect (OSTI)

    Zhang, Ruohui; Fan, Xiaomei; Bai, Wenwen; Han, Chun

    2014-08-15

    Objective: The purpose of this study is to propose an alternative planning approach for VMAT using constant dose rate and gantry speed arc therapy(CDR-CAS-IMAT) implementation on conventional Linac Varian 23EX and used IMRT as a benchmark to evaluate the performance. Methods and materials: Eighteen patients with thoracic esophageal carcinoma who were previously treated with IMRT on Varian 23EX were retrospectively planned for CDR-CAS-IMAT plans. Dose prescription was set to 60 Gy to PTVs in 30 fractions. The planning objectives for PTVs and OAR were corresponding with the IMRT plans. Dose to the PTVs and OAR were compared to IMRT with respect to plan quality, MU, treatment time and delivery accuracy. Results: CDR-CAS-IMAT plans led to equivalent or superior plan quality as compared to IMRT, PTV's CI relative increased 16.2%, while small deviations were observed on minimum dose for PTV. Volumes in the cord receiving 40Gy were increased from 3.6% with IMRT to 7.0%. Treatment times were reduced significantly with CDR-CAS-IMAT(mean 85.7s vs. 232.1s, p < .05), however, MU increased by a factor of 1.3 and lung V10/5/3.5/aver were relative increase 6.7%,12%,17.9%,4.2%, respectively. And increased the E-P low dose area volume decreased the hight dose area. There were no significant difference in Delta4 measurements results between both planning techniques. Conclusion: CDR-CAS-IMAT plans can be implemented smoothly and quickly into a busy cancer center, which improved PTV CI and reduces treatment time but increased the MU and low dose irradiated area. An evaluation of weight loss must be performed during treatment for CDR-CAS-IMAT patients.

  10. 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.

    2012-06-01

    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.

  11. Wind farm electrical system

    DOE Patents [OSTI]

    Erdman, William L.; Lettenmaier, Terry M.

    2006-07-04

    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.

  12. Naval Station Newport Wind Resource Assessment. A Study Prepared...

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

    ... wind speeds, energy production for a generic 1.5 MW wind turbine, and capacity factor. ... resource at the selected sites at NAVSTA Newport is sufficient for a wind turbine project. ...

  13. Atmosphere to Electrons: Enabling the Wind Plant of Tomorrow

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... measures wind speed and wind direction offshore at turbine hub-height and across the blade span. ... In simulations of existing wind farms, increases in energy capture of 3% have ...

  14. SWERA/Wind Resource Information | Open Energy Information

    Open Energy Info (EERE)

    wind resources are depicted as average wind speed (meters per second) or wind power density (watts per square meter) at a specified height above the ground (nominally 50 m)....

  15. Scale Models and Wind Turbines

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    As wind turbines and wind farms become larger to take advantage of the economies of scale and increased wind speeds at higher altitudes, their impact in the locales where they are sited becomes more dramatic. One place this is especially contentious is in the offshore environment of the Northeast. This lesson explores scale models and the issues surrounding models and their accuracy when developing a large wind farm. Worksheets are included.

  16. Cherokee Nation Enterprises - Wind Development

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Businesses Tribal Energy Program 2008 November 18, 2008 HEROKEE C N E R G ATION NERGY by ENEWABLE ENERATION Wind Farm Project Location Wind Speeds Measured for 4 Years at Chilocco. . . Class III Commercial Wind! ROI in less than 6 years $672+ Million Net Income for 25 yrs. ONLY if we own 100% Precise Project Management *Vendor Reliability *Knowledgeable Personnel *Timetables and Schedule Mgmt. Risk Management Risk Management Risk Management Investment vs. Expenses (Revenue for 2007) GAMING WIND

  17. 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.

    1982-08-01

    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)

  18. 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.

    1983-03-01

    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)

  19. West Winds Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Winds Wind Farm Jump to: navigation, search Name West Winds Wind Farm Facility West Winds Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner...

  20. 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.

    2012-11-01

    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.

  1. Wind turbine performance under icing conditions

    SciTech Connect (OSTI)

    Jasinski, W.J.; Noe, S.C.; Selig, M.S.; Bragg, M.B.

    1998-02-01

    The effects of rime ice on horizontal axis wind turbine performance were estimated. For typical supercooled fog conditions found in cold northern regions, four rime ice accretions on the S809 wind turbine airfoil were predicted using the NASA LEWICE code. The resulting airfoil/ice profile combinations were wind tunnel tested to obtain the lift, drag, and pitching moment characteristics over the Reynolds number range 1--2 {times} 10{sup 6}. These data were used in the PROPID wind turbine performance prediction code to predict the effects of rime ice on a 450-kW rated-power, 28.7-m diameter turbine operated under both stall-regulated and variable-speed/variable-pitch modes. Performance losses on the order of 20% were observed for the variable-speed/variable-pitch rotor. For the stall-regulated rotor, however, a relatively small rime ice profile yielded significantly larger performance losses. For a larger 0.08c-long rime ice protrusion, however, the rated peak power was exceeded by 16% because at high angles the rime ice shape acted like a leading edge flap, thereby increasing the airfoil C{sub l,max} and delaying stall.

  2. Featured Publications from the Bats and Wind Energy Cooperative |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Featured Publications from the Bats and Wind Energy Cooperative Featured Publications from the Bats and Wind Energy Cooperative Since its formation in 2003, the Bats and Wind Energy Cooperative (BWEC) has been engaged in numerous research activities funded by DOE's National Renewable Energy Laboratory, including studies assessing the impact of altering the cut-in-speed of wind turbines (the minimum wind speed at which wind turbines begin producing power), and the use of

  3. United States Wind Energy Growth and Policy Framework: Preprint

    SciTech Connect (OSTI)

    Calvert, S. D.; Hock, S. M.

    2001-07-01

    Wind is the fastest growing source for electricity in the United States. During 2001, U.S. wind power plant installations are expected to increase by 1,850 megawatts (MW), resulting in a total installed capacity of about 4,400 MW. The market expansion is supported by a variety of Federal and state incentives in the form of production tax credits, renewable energy production incentives, renewable energy portfolio standards, and others. New mechanisms include green power offerings, green tags, and government power purchases. Deregulation of the electric power industry is continuing. In some cases this is allowing higher electricity rates that may increase the rate of wind plant development. Power shortages, natural gas price increases, and enforcement of clean air laws are increasingly important wind market drivers in some regions. Continuing research and technology development has reduced wind energy costs dramatically to less than $0.04/kWh for large projects at sites with ave rage wind speeds higher than 7.0 m/s, making wind the least-cost option in some power markets. The recently published National Energy Policy contains recommendations to increase wind energy development and improve the power transmission system.

  4. Distributed Wind Energy in Idaho

    SciTech Connect (OSTI)

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

    2009-01-31

    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

  5. Wind farm array wake losses

    SciTech Connect (OSTI)

    Baker, R.W.; McCarthy, E.F.

    1997-12-31

    A wind turbine wake study was conducted in the summer of 1987 at an Altamont Pass wind electric generating facility. The wind speed deficits, turbulence, and power deficits from an array consisting of several rows of wind turbines is discussed. A total of nine different test configurations were evaluated for a downwind spacing ranging from 7 rotor diameters (RD) to 34 RD and a cross wind spacing of 1.3 RD and 2.7 RD. Wake power deficits of 15% were measured at 16 RD and power losses of a few percent were even measurable at 27 RD for the closer cross wind spacing. For several rows of turbines separated by 7-9 RD the wake zones overlapped and formed compound wakes with higher velocity deficits. The wind speed and direction turbulence in the wake was much higher than the ambient turbulence. The results from this study are compared to the findings from other similar field measurements.

  6. Wind Integration

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

    Wind Generation - ScheduledActual Balancing Reserves - Deployed Near Real-time Wind Animation Wind Projects under Review Growth Forecast Fact Sheets Working together to address...

  7. Active control system for high speed windmills

    SciTech Connect (OSTI)

    Avery, D.E.

    1988-01-12

    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.

  8. Active control system for high speed windmills

    SciTech Connect (OSTI)

    Avery, Don E.

    1988-01-01

    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.

  9. Optimum propeller wind turbines

    SciTech Connect (OSTI)

    Sanderson, R.J.; Archer, R.D.

    1983-11-01

    The Prandtl-Betz-Theodorsen theory of heavily loaded airscrews has been adapted to the design of propeller windmills which are to be optimized for maximum power coefficient. It is shown that the simpler, light-loading, constant-area wake assumption can generate significantly different ''optimum'' performance and geometry, and that it is therefore not appropriate to the design of propeller wind turbines when operating in their normal range of high-tip-speed-to-wind-speed ratio. Design curves for optimum power coefficient are presented and an example of the design of a typical two-blade optimum rotor is given.

  10. Prairie Winds Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Wind Farm Jump to: navigation, search Name Prairie Winds Wind Farm Facility Prairie Winds Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner...

  11. Wind Resource Assessment and Characterization | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Resource Assessment and Characterization Wind Resource Assessment and Characterization A crucial factor in the development, siting, and operation of a wind farm is the ability to assess and characterize available wind resources. The Wind Program supports efforts to accurately define, measure, and forecast the nation's land-based and offshore wind resources. More accurate prediction and measurement of wind speed and direction allow wind farms to supply clean, renewable power to businesses and

  12. Damage measurements on the NWTC direct-drive, variable-speed test bed

    SciTech Connect (OSTI)

    Sutherland, H.J.; Carlin, P.W.

    1998-12-31

    The NWTC (National Wind Technology Center) Variable-Speed Test Bed turbine is a three-bladed, 10-meter, downwind machine that can be run in either fixed-speed or variable-speed mode. In the variable-speed mode, the generator torque is regulated, using a discrete-stepped load bank to maximize the turbine`s power coefficient. At rated power, a second control loop that uses blade pitch to maintain rotor speed essentially as before, i.e., using the load bank to maintain either generator power or (optionally) generator torque. In this paper, the authors will use this turbine to study the effect of variable-speed operation on blade damage. Using time-series data obtained from blade flap and edge strain gauges, the load spectrum for the turbine is developed using rainflow counting techniques. Miner`s rule is then used to determine the damage rates for variable-speed and fixed-speed operation. The results illustrate that the controller algorithm used with this turbine introduces relatively large load cycles into the blade that significantly reduce its service lifetime, while power production is only marginally increased.

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

    SciTech Connect (OSTI)

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

    1982-06-01

    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.

  14. Doppler Lidar Wind Value-Added Product

    SciTech Connect (OSTI)

    Newsom, R. K.; Sivaraman, C.; Shippert, T. R.; Riihimaki, L. D.

    2015-07-01

    Wind speed and direction, together with pressure, temperature, and relative humidity, are the most fundamental atmospheric state parameters. Accurate measurement of these parameters is crucial for numerical weather prediction. Vertically resolved wind measurements in the atmospheric boundary layer are particularly important for modeling pollutant and aerosol transport. Raw data from a scanning coherent Doppler lidar system can be processed to generate accurate height-resolved measurements of wind speed and direction in the atmospheric boundary layer.

  15. Offshore Wind Potential Tables

    Wind Powering America (EERE)

    Offshore wind resource by state and wind speed interval within 50 nm of shore. Wind Speed at 90 m (m/s) 7.0 - 7.5 7.5 - 8.0 8.0 - 8.5 8.5 - 9.0 9.0 - 9.5 9.5 - 10.0 >10.0 Total >7.0 State Area km 2 (MW) Area km 2 (MW) Area km 2 (MW) Area km 2 (MW) Area km 2 (MW) Area km 2 (MW) Area km 2 (MW) Area km 2 (MW) California 11,439 (57,195) 24,864 (124,318) 23,059 (115,296) 22,852 (114,258) 13,185 (65,924) 15,231 (76,153) 6,926 (34,629) 117,555 (587,773) Connecticut 530 (2,652) 702 (3,508) 40

  16. Offshore Wind

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

    ... HomeStationary PowerEnergy Conversion EfficiencyWind EnergyOffshore Wind Offshore Wind Tara Camacho-Lopez 2016-0... March 2014, Barcelona, Spain, PO 225. Griffith, D.T., and ...

  17. wind energy

    National Nuclear Security Administration (NNSA)

    5%2A en Pantex to Become Wind Energy Research Center http:nnsa.energy.govfieldofficesnponpopressreleasespantex-become-wind-energy-research-center

  18. Wind News

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

    ... laboratory mission technologies and ... By admin| ... participating in the Wind Turbine Radar Interference ... Association AWEA WindPower 2015 event in Orlando, Florida. ...

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

    SciTech Connect (OSTI)

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

    2006-10-01

    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.

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

    SciTech Connect (OSTI)

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

    2012-08-01

    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.

  1. Articles about Wind Program Analysis | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Cause the Majority of Wind Turbine Gearbox Failures In the past, the wind energy ... three major components: a single-stage gearbox, a medium-speed permanent-magnet ...

  2. Final Report on the Creation of the Wind Integration National...

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

    ... was not considered, since DOE is investigating offshore floating platforms. ... speed for a cell with a single turbine to a 5% reduction in wind speed for a cell with 8 turbines ...

  3. 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.

    2012-10-01

    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.

  4. Wind farm production cost: Optimum turbine size and farm capacity in the actual market

    SciTech Connect (OSTI)

    Laali, A.R.; Meyer, J.L.; Bellot, C.; Louche, A.

    1996-12-31

    Several studies are undertaken in R&D Division of EDF in collaboration with ERASME association in order to have a good knowledge of the wind energy production costs. These studies are performed in the framework of a wind energy monitoring project and concern the influence of a few parameters like wind farm capacity, turbine size and wind speed on production costs, through an analysis of the actual market trend. Some 50 manufacturers and 140 different kind of wind turbines are considered for this study. The minimum production cost is situated at 800/900 kW wind turbine rated power. This point will probably move to more important powers in the future. This study is valid only for average conditions and some special parameters like particular climate conditions or lack of infrastructure for a special site the could modify the results shown on the curves. The variety of wind turbines (rated power as a function of rotor diameter, height and specific rated power) in the actual market is analyzed. A brief analysis of the market trend is also performed. 7 refs., 7 figs.

  5. 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

    2011-03-28

    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.

  6. How Does a Wind Turbine Work? | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Does a Wind Turbine Work? How Does a Wind Turbine Work? How does a wind turbine work? Previous Next Wind turbines operate on a simple principle. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity. Click NEXT to learn more. Blades Rotor Low Speed Shaft Gear Box High Speed Shaft Generator Anemometer Controller Pitch System Brake Wind Vane Yaw Drive Yaw Motor Tower Nacelle

  7. How a Wind Turbine Works | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    a Wind Turbine Works How a Wind Turbine Works June 20, 2014 - 9:09am Addthis How does a wind turbine work? Previous Next Wind turbines operate on a simple principle. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity. Click NEXT to learn more. Blades Rotor Low Speed Shaft Gear Box High Speed Shaft Generator Anemometer Controller Pitch System Brake Wind Vane Yaw Drive Yaw Motor

  8. 20% Wind Energy by 2030 - Chapter 2: Wind Turbine Technology Summary Slides

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2: Wind Turbine Technology Summary Slides Anatomy of a 1.5-MW wind turbine Nacelle enclosing: * Low-speed shaft * Gearbox * Generator, 1.5 MW * Electrical controls * Blade pitch controls Rotor Hub Tower, 80 m Minivan Rotor blades: * Shown feathered * Length, 37-m Larger and taller turbines are needed to capture optimal wind resources Wind power is competitive with wholesale prices Source: Wiser and Bolinger, 2009 Note: Wholesale price range reflects flat block of power across 23 pricing

  9. Evaluation of WRF predicted near hub-height winds and ramp events over a Pacific Northwest site with complex terrain

    SciTech Connect (OSTI)

    Yang, Qing; Berg, Larry K.; Pekour, Mikhail S.; Fast, Jerome D.; Newsom, Rob K.; Stoelinga, Mark; Finley, Cathy

    2013-08-16

    The WRF model version 3.3 is used to simulate near hub-height winds and power ramps utilizing three commonly used planetary boundary-layer (PBL) schemes: Mellor-Yamada-Janji? (MYJ), University of Washington (UW), and Yonsei University (YSU). The predicted winds have small mean biases compared with observations. Power ramps and step changes (changes within an hour) consistently show that the UW scheme performed better in predicting up ramps under stable conditions with higher prediction accuracy and capture rates. Both YSU and UW scheme show good performance predicting up- and down- ramps under unstable conditions with YSU being slightly better for ramp durations longer than an hour. MYJ is the most successful simulating down-ramps under stable conditions. The high wind speed and large shear associated with low-level jets are frequently associated with power ramps, and the biases in predicted low-level jet explain some of the shown differences in ramp predictions among different PBL schemes. Low-level jets were observed as low as ~200 m in altitude over the Columbia Basin Wind Energy Study (CBWES) site, located in an area of complex terrain. The shear, low-level peak wind speeds, as well as the height of maximum wind speed are not well predicted. Model simulations with 3 PBL schemes show the largest variability among them under stable conditions.

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

    SciTech Connect (OSTI)

    Baring-Gould, I.

    2009-04-01

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

    SciTech Connect (OSTI)

    Baring-Gould, I.

    2009-04-01

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

  12. Cisco Wind Energy Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Cisco Wind Energy Wind Farm Jump to: navigation, search Name Cisco Wind Energy Wind Farm Facility Cisco Wind Energy Sector Wind energy Facility Type Commercial Scale Wind Facility...

  13. Wind Easements

    Broader source: Energy.gov [DOE]

    The statutes authorizing the creation of wind easements include several provisions to protect property owners. For example, a wind easement may not make the property owner liable for any property...

  14. Wind Farm

    Broader source: Energy.gov [DOE]

    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...

  15. Wind Power

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

    Wind Power As the accompanying map of New Mexico shows, the best wind power generation potential near WIPP is along the Delaware Mountain ridge line of the southern Guadalupe Mountains, about 50-60 miles southwest. The numeric grid values indicate wind potential, with a range from 1 (poor) to 7 (superb). Just inside Texas in the southern Guadalupe Mountains, the Delaware Mountain Wind Power Facility in Culbertson County, Texas currently generates over 30 MW, and could be expanded to a 250 MW

  16. Statistical and Spectral Analysis of Wind Characteristics Relevant to Wind Energy Assessment Using Tower Measurements in Complex Terrain

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Belu, Radian; Koracin, Darko

    2013-01-01

    The main objective of the study was to investigate spatial and temporal characteristics of the wind speed and direction in complex terrain that are relevant to wind energy assessment and development, as well as to wind energy system operation, management, and grid integration. Wind data from five tall meteorological towers located in Western Nevada, USA, operated from August 2003 to March 2008, used in the analysis. The multiannual average wind speeds did not show significant increased trend with increasing elevation, while the turbulence intensity slowly decreased with an increase were the average wind speed. The wind speed and direction weremore » modeled using the Weibull and the von Mises distribution functions. The correlations show a strong coherence between the wind speed and direction with slowly decreasing amplitude of the multiday periodicity with increasing lag periods. The spectral analysis shows significant annual periodicity with similar characteristics at all locations. The relatively high correlations between the towers and small range of the computed turbulence intensity indicate that wind variability is dominated by the regional synoptic processes. Knowledge and information about daily, seasonal, and annual wind periodicities are very important for wind energy resource assessment, wind power plant operation, management, and grid integration.« less

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

    SciTech Connect (OSTI)

    Huskey, A.

    2011-11-01

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

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

    SciTech Connect (OSTI)

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

    2012-07-01

    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).

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

    SciTech Connect (OSTI)

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

    1984-09-01

    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.

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

    SciTech Connect (OSTI)

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

    2014-04-09

    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

  1. Hurricane Katrina Wind Investigation Report

    SciTech Connect (OSTI)

    Desjarlais, A. O.

    2007-08-15

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

    SciTech Connect (OSTI)

    Baker, Robert W.; Hewson, E. Wendell

    1980-10-01

    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.

  3. Guide to Using the WIND Toolkit Validation Code

    SciTech Connect (OSTI)

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

    2014-12-01

    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.

  4. Wind Workshop

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

    Department of Energy Wind Turbine Manufacturing Transforms with Three-Dimensional Printing Wind Turbine Manufacturing Transforms with Three-Dimensional Printing May 19, 2016 - 12:57pm Addthis From medical devices to airplane components, three-dimensional (3-D) printing (also called additive manufacturing) is transforming the manufacturing industry. Now, research that supports the Energy Department's Atmosphere to Electrons (A2e) initiative is applying 3-D-printing processes to create wind

  5. Wind News

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

    Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & ...

  6. Wind Energy

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

    Stationary Power/Energy Conversion Efficiency/Wind Energy Wind Energy Tara Camacho-Lopez 2016-08-30T20:56:10+00:00 Increasing the viability of wind energy technology by applying research to improve wind turbine performance and reliability http://windworkshops.sandia.gov/ Rotor Innovation Advancing rotor technology such that they capture more energy, more reliably, with relatively lower system loads-all at a lower end cost. SWiFT Facility & Testing Improving the performance and reducing the

  7. Wind Power Forecasting Data

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

    Operations Call 2012 Retrospective Reports 2012 Retrospective Reports 2011 Smart Grid Wind Integration Wind Integration Initiatives Wind Power Forecasting Wind Projects Email...

  8. NREL: Wind Research - Wind Career Map Shows Wind Industry Career...

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

    Wind Career Map Shows Wind Industry Career Opportunities, Paths A screenshot of the wind career map showing the various points on a chart that show different careers in the wind...

  9. Vehicle speed control device

    SciTech Connect (OSTI)

    Thornton-Trump, W.E.

    1987-03-10

    An apparatus is described for automatically limiting the speed of a vehicle powered by an internal combustion engine having a spark ignition system with an ignition coil, comprising: sensor means for generating a speed signal directly representative of the speed of the vehicle comprising a series of speed signal pulses having a pulse repetition frequency proportional to the speed of the vehicle; control means for converting speed signal pulses into a DC voltage proportional to the vehicle speed; means for comparing the DC voltage to a predetermined DC voltage having substantially zero AC components representative of a predetermined maximum speed and for generating a difference signal in response thereto; and means for generating a pulse-width modulated control signal responsive to the difference signal; power means responsive to the control signal for intermittently interrupting the ignition system.

  10. Stetson Wind Expansion Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Stetson Wind Expansion Wind Farm Jump to: navigation, search Name Stetson Wind Expansion Wind Farm Facility Stetson Wind Expansion Sector Wind energy Facility Type Commercial Scale...

  11. State Fair Wind Energy Education Center Wind Farm | Open Energy...

    Open Energy Info (EERE)

    Fair Wind Energy Education Center Wind Farm Jump to: navigation, search Name State Fair Wind Energy Education Center Wind Farm Facility Wind Energy Education Center Sector Wind...

  12. Wind Power Partners '94 Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    4 Wind Farm Jump to: navigation, search Name Wind Power Partners '94 Wind Farm Facility Wind Power Partners '94 Sector Wind energy Facility Type Commercial Scale Wind Facility...

  13. Wethersfield Wind Power Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Wethersfield Wind Power Wind Farm Jump to: navigation, search Name Wethersfield Wind Power Wind Farm Facility Wethersfield Wind Power Sector Wind energy Facility Type Commercial...

  14. Portsmouth Abbey School Wind Turbine Wind Farm | Open Energy...

    Open Energy Info (EERE)

    Abbey School Wind Turbine Wind Farm Jump to: navigation, search Name Portsmouth Abbey School Wind Turbine Wind Farm Facility Portsmouth Abbey School Wind Turbine Sector Wind energy...

  15. Harbec Plastic Wind Turbine Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Harbec Plastic Wind Turbine Wind Farm Jump to: navigation, search Name Harbec Plastic Wind Turbine Wind Farm Facility Harbec Plastic Wind Turbine Sector Wind energy Facility Type...

  16. Trailing edge devices to improve performance and increase lifetime of wind-electric water pumping systems

    SciTech Connect (OSTI)

    Vick, B.D.; Clark, R.N.

    1996-12-31

    Trailing edge flaps were applied to the blades of a 10 kW wind turbine used for water pumping to try to improve the performance and decrease the structural fatigue on the wind turbine. Most small wind turbines (10 kW and below) use furling (rotor turns out of wind similar to a mechanical windmill) to protect the wind turbine from overspeed during high winds. Some small wind turbines, however, do not furl soon enough to keep the wind turbine from being off line part of the time in moderately high wind speeds (10 - 16 m/s). As a result, the load is disconnected and no water is pumped at moderately high wind speeds. When the turbine is offline, the frequency increases rapidly often causing excessive vibration of the wind turbine and tower components. The furling wind speed could possibly be decreased by increasing the offset between the tower centerline and the rotor centerline, but would be a major and potentially expensive retrofit. Trailing edge flaps (TEF) were used as a quick inexpensive method to try to reduce the furling wind speed and increase the on time by reducing the rotor RPM. One TEF configuration improved the water pumping performance at moderately high wind speeds, but degraded the pumping performance at low wind speeds which resulted in little change in daily water volume. The other TEF configuration differed very little from the no flap configuration. Both TEF configurations however, reduced the rotor RPM in high wind conditions. The TEF, did not reduce the rotor RPM by lowering the furling wind speed as hoped, but apparently did so by increasing the drag which also reduced the volume of water pumped at the lower wind speeds. 6 refs., 9 figs.

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

    SciTech Connect (OSTI)

    van Dam, J.; Jager, D.

    2010-02-01

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

  18. NREL Controllable Grid Interface for Testing MW-Scale Wind Turbine Generators (Poster)

    SciTech Connect (OSTI)

    McDade, M.; Gevorgian, V.; Wallen, R.; Erdman, W.

    2013-04-01

    In order to understand the behavior of wind turbines experiencing grid disturbances, it is necessary to perform a series of tests and accurate transient simulation studies. The latest edition of the IEC 61400-21 standard describes methods for such tests that include low voltage ride-through (LVRT), active power set-point control, ramp rate limitations, and reactive power capability tests. The IEC methods are being widely adopted on both national and international levels by wind turbine manufacturers, certification authorities, and utilities. On-site testing of wind turbines might be expensive and time consuming since it requires both test equipment transportation and personnel presence in sometimes remote locations for significant periods of time because such tests need to be conducted at certain wind speed and grid conditions. Changes in turbine control software or design modifications may require redoing of all tests. Significant cost and test-time reduction can be achieved if these tests are conducted in controlled laboratory environments that replicate grid disturbances and simulation of wind turbine interactions with power systems. Such testing capability does not exist in the United States today. An initiative by NREL to design and construct a 7-MVA grid simulator to operate with the existing 2.5 MW and new upcoming 5-MW dynamometer facilities will fulfill this role and bring many potential benefits to the U.S. wind industry with the ultimate goal of reducing wind energy integration costs.

  19. NREL: Wind Research - Offshore Wind Research

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

    NREL's Offshore Wind Testing Capabilities 35 years of wind turbine testing experience ... Testing Applying 35 years of wind turbine testing expertise, NREL has developed ...

  20. NREL: Wind Research - Small Wind Turbine Development

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

    Small Wind Turbine Development A photo of Southwest Windpower's Skystream wind turbine in front of a home. PIX14936 Southwest Windpower's Skystream wind turbine. A photo of the ...

  1. Danielson Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Danielson Wind Facility Danielson Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Developer Juhl Wind...

  2. Kawailoa Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Kawailoa Wind Facility Kawailoa Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner First Wind...

  3. Palouse Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Palouse Wind Facility Palouse Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner First Wind...

  4. Harbor Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Harbor Wind Facility Harbor Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Harbor Wind LLC...

  5. Kahuku Wind | Open Energy Information

    Open Energy Info (EERE)

    Kahuku Wind Jump to: navigation, search Name Kahuku Wind Facility Kahuku Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner First Wind...

  6. Wiota Wind | Open Energy Information

    Open Energy Info (EERE)

    Wiota Wind Jump to: navigation, search Name Wiota Wind Facility Wiota Wind Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Wiota Wind Energy LLC...

  7. Bravo Wind | Open Energy Information

    Open Energy Info (EERE)

    Bravo Wind Jump to: navigation, search Name Bravo Wind Facility Bravo Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status Proposed Developer Bravo Wind LLC...

  8. Auwahi Wind | Open Energy Information

    Open Energy Info (EERE)

    Auwahi Wind Jump to: navigation, search Name Auwahi Wind Facility Auwahi Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner BP Wind Energy...

  9. Traer Wind | Open Energy Information

    Open Energy Info (EERE)

    Traer Wind Jump to: navigation, search Name Traer Wind Facility Traer Wind Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Norsemen Wind Energy LLC...

  10. Sheffield Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Sheffield Wind Facility Sheffield Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner First Wind...

  11. Rollins Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Rollins Wind Facility Rollins Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner First Wind...

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

    SciTech Connect (OSTI)

    Davis, H.C.; Brandemuehl, M.J.; Bergey, M.L.S.

    1995-01-01

    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.

  13. High Resolution Atmospheric Modeling for Wind Energy Applications

    SciTech Connect (OSTI)

    Simpson, M; Bulaevskaya, V; Glascoe, L; Singer, M

    2010-03-18

    The ability of the WRF atmospheric model to forecast wind speed over the Nysted wind park was investigated as a function of time. It was found that in the time period we considered (August 1-19, 2008), the model is able to predict wind speeds reasonably accurately for 48 hours ahead, but that its forecast skill deteriorates rapidly after 48 hours. In addition, a preliminary analysis was carried out to investigate the impact of vertical grid resolution on the forecast skill. Our preliminary finding is that increasing vertical grid resolution does not have a significant impact on the forecast skill of the WRF model over Nysted wind park during the period we considered. Additional simulations during this period, as well as during other time periods, will be run in order to validate the results presented here. Wind speed is a difficult parameter to forecast due the interaction of large and small length scale forcing. To accurately forecast the wind speed at a given location, the model must correctly forecast the movement and strength of synoptic systems, as well as the local influence of topography / land use on the wind speed. For example, small deviations in the forecast track or strength of a large-scale low pressure system can result in significant forecast errors for local wind speeds. The purpose of this study is to provide a preliminary baseline of a high-resolution limited area model forecast performance against observations from the Nysted wind park. Validating the numerical weather prediction model performance for past forecasts will give a reasonable measure of expected forecast skill over the Nysted wind park. Also, since the Nysted Wind Park is over water and some distance from the influence of terrain, the impact of high vertical grid spacing for wind speed forecast skill will also be investigated.

  14. 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.

  15. 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.

  16. 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

    2014-05-01

    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.

  17. Wyoming Wind Power Project (generation/wind)

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

    Wind Power > Generation Hydro Power Wind Power Monthly GSP BPA White Book Dry Year Tools Firstgov Wyoming Wind Power Project (Foote Creek Rim I and II) Thumbnail image of wind...

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

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy South Carolina Opens Nation's Largest Wind Drivetrain Testing Facility South Carolina Opens Nation's Largest Wind Drivetrain Testing Facility November 27, 2013 - 12:00am Addthis The Energy Department and Clemson University officials on November 21 dedicated the nation's largest wind energy testing facility in North Charleston, South Carolina. The facility will help test and validate new turbines, particularly for offshore wind- €helping to speed deployment of next

  19. NREL Readies New Wind Turbine Drivetrain for Commercialization | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Readies New Wind Turbine Drivetrain for Commercialization NREL Readies New Wind Turbine Drivetrain for Commercialization May 18, 2015 - 3:52pm Addthis Illustration of a wind turbine drivetrain with a transparent case that shows the internal gears. In February, engineers at the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) assembled the innovative, medium-speed, medium-voltage wind turbine drivetrain that was the result of a study funded by DOE's

  20. 2011 DOE Funded Offshore Wind Project Updates | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2011 DOE Funded Offshore Wind Project Updates 2011 DOE Funded Offshore Wind Project Updates September 12, 2014 - 10:52am Addthis For the past few years, much of the U.S. Department of Energy's (DOE's) Wind Program research and development efforts have been focused on accelerating the development and deployment of offshore wind energy technology. In 2011, DOE awarded $43 million to 41 projects across 20 states to speed technical innovations, lower costs, and shorten the timeline for deploying

  1. LLNL Predicts Wind Power with Greater Accuracy | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    LLNL Predicts Wind Power with Greater Accuracy LLNL Predicts Wind Power with Greater Accuracy May 18, 2015 - 5:05pm Addthis A multicolored scatter plot that curves from left to right, bottom to top to show the wind power capacity factor and wind speed meters per second. The colors relate atmospheric stability conditions to reported power-output observations with black, dark blue, and lighter blue representing stable conditions; light blue, green and light green representing neutral conditions;

  2. Offshore Wind Power USA

    Broader source: Energy.gov [DOE]

    The Offshore Wind Power USA conference provides the latest offshore wind market updates and forecasts.

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

    SciTech Connect (OSTI)

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

    2009-02-01

    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.

  4. Wind Energy

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

    Wind Energy The DTU SpinnerLidar installed in the nacelle of the SWiFT facility A1 turbine Permalink Gallery First Wake Data Captured During Wake Steering Experiment at the SWiFT Facility News, Renewable Energy, SWIFT, Wind Energy, Wind News First Wake Data Captured During Wake Steering Experiment at the SWiFT Facility Researchers at Sandia National Laboratories and the National Renewable Energy Laboratory (NREL) have met a major project milestone as part of the Department of Energy Atmosphere

  5. 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.

    1981-03-01

    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.

  6. 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.

    1981-02-01

    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.

  7. WINDExchange: Selling Wind Power

    Wind Powering America (EERE)

    Market Sectors Printable Version Bookmark and Share Utility-Scale Wind Distributed Wind Motivations for Buying Wind Power Buying Wind Power Selling Wind Power Selling Wind Power Owners of wind turbines interconnected directly to the transmission or distribution grid, or that produce more power than the host consumes, can sell wind power as well as other generation attributes. Wind-Generated Electricity Electricity generated by wind turbines can be used to cover on-site energy needs

  8. Analysis of a teetered, variable-speed rotor: final report

    SciTech Connect (OSTI)

    Weber, T.L.; Wilson, R.E.; Walker, S.N. . Dept. of Mechanical Engineering)

    1991-06-01

    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.

  9. THE TURBULENT CASCADE AND PROTON HEATING IN THE SOLAR WIND DURING SOLAR MINIMUM

    SciTech Connect (OSTI)

    Coburn, Jesse T.; Smith, Charles W.; Vasquez, Bernard J.; Stawarz, Joshua E.; Forman, Miriam A. E-mail: Charles.Smith@unh.edu E-mail: Joshua.Stawarz@Colorado.edu

    2012-08-01

    The recently protracted solar minimum provided years of interplanetary data that were largely absent in any association with observed large-scale transient behavior on the Sun. With large-scale shear at 1 AU generally isolated to corotating interaction regions, it is reasonable to ask whether the solar wind is significantly turbulent at this time. We perform a series of third-moment analyses using data from the Advanced Composition Explorer. We show that the solar wind at 1 AU is just as turbulent as at any other time in the solar cycle. Specifically, the turbulent cascade of energy scales in the same manner proportional to the product of wind speed and temperature. Energy cascade rates during solar minimum average a factor of 2-4 higher than during solar maximum, but we contend that this is likely the result of having a different admixture of high-latitude sources.

  10. Feasibility of utilizing wind energy in Thailand

    SciTech Connect (OSTI)

    Jamkrajang, M.

    1984-01-01

    The purpose of this study was to ascertain the feasibility of utilizing wind energy to meet part of the energy demands related to pumping water and to generating electricity for the rural households in Thailand. The data for this study were divided into three different areas: (1) wind speed data, (2) the wind machine performance data, and (3) the rural energy demand data. The wind machine were divided into two categories of water-pumping windmills and electricity-generating wind machines. Three types of water pumping windmills and one type of electricity-generating wind machine were matched with the wind condition in Thailand. They were the multi-blade rotor, the sailwing rotor model (WE 002), the slow-speed sailwing rotor, and the Aerowatt model (1100 FP5G) respectively. It was concluded that, in Thailand: (1) the multiblade rotor and the sail-wing rotor (WE 002) windmill is suitable for pumping water for domestic use at 43 specified locations; (2) the slow-speed sailwing rotor windmill is suitable for pumping water for small irrigation at 32 specified locations; and (3) the Aerowatt model (1100 GP5G) is suitable for generating electricity for household use at 29 specified locations.

  11. Wind Turbine Wake-Redirection Control at the Fishermen's Atlantic City Windfarm: Preprint

    SciTech Connect (OSTI)

    Churchfield, M.; Fleming, P.; Bulder, B.; White, S.

    2015-05-06

    In this paper, we will present our work towards designing a control strategy to mitigate wind turbine wake effects by redirecting the wakes, specifically applied to the Fishermen’s Atlantic City Windfarm (FACW), proposed for deployment off the shore of Atlantic City, New Jersey. As wind turbines extract energy from the air, they create low-speed wakes that extend behind them. Full wake recovery Full wake recovery to the undisturbed wind speed takes a significant distance. In a wind energy plant the wakes of upstream turbines may travel downstream to the next row of turbines, effectively subjecting them to lower wind speeds, meaning these waked turbines will produce less power.

  12. 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.

    2010-05-01

    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.

  13. The Inside of a Wind Turbine | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The Inside of a Wind Turbine The Inside of a Wind Turbine 1 of 17 Tower: 2 of 17 Tower: Made from tubular steel (shown here), concrete, or steel lattice. Supports the structure of the turbine. Because wind speed increases with height, taller towers enable turbines to capture more energy and generate more electricity. Generator: 3 of 17 Generator: Produces 60-cycle AC electricity; it is usually an off-the-shelf induction generator. High-speed shaft: 4 of 17 High-speed shaft: Drives the generator.

  14. Main Coast Winds - Final Scientific Report

    SciTech Connect (OSTI)

    Jason Huckaby; Harley Lee

    2006-03-15

    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.

  15. Milford Wind Corridor Phase I (Clipper) Wind Farm | Open Energy...

    Open Energy Info (EERE)

    Clipper) Wind Farm Jump to: navigation, search Name Milford Wind Corridor Phase I (Clipper) Wind Farm Facility Milford Wind Corridor Phase I (Clipper) Sector Wind energy Facility...

  16. A digital video camera for application of particle image velocimetry in high-speed flows

    SciTech Connect (OSTI)

    Willert, C.; Stasicki, B.; Raffel, M.; Kompenhans, J.

    1995-12-31

    A high-speed digital camera based on video technology for application of particle image velocimetry in wind tunnels is described. The camera contains two independently triggerable interline CCD sensors which are mounted on two faces of a cube beam splitter permitting the use of a single lens. Each of the sensors has a minimal exposure time of 0.8 {micro}s with a trigger response time of less than 1 {micro}s. The asynchronous reset capability permits the camera to trigger directly off a pulsed laser with a repetition rate differing from the standard 25 Hz CCIR video frame rate. Captured images are digitized within and stored in RAM the camera which can be read through the parallel port of a computer. The camera is software configurable with the settings being non-volatile. Technical aspects such as sensor alignment and calibration through software are described. Close-up PIV measurements on a free jet illustrate that, in the future, the camera can be successfully utilized at imaging high-speed flows over a small field of view covering several cm{sup 2}, such as the flow between turbine blades. Further, the electronic shutter permits its use in luminous environments such as illuminated laboratories, wind tunnels or flames.

  17. Variability of interconnected wind plants: correlation length and its dependence on variability time scale

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    St. Martin, Clara M.; Lundquist, Julie K.; Handschy, Mark A.

    2015-04-02

    The variability in wind-generated electricity complicates the integration of this electricity into the electrical grid. This challenge steepens as the percentage of renewably-generated electricity on the grid grows, but variability can be reduced by exploiting geographic diversity: correlations between wind farms decrease as the separation between wind farms increases. However, how far is far enough to reduce variability? Grid management requires balancing production on various timescales, and so consideration of correlations reflective of those timescales can guide the appropriate spatial scales of geographic diversity grid integration. To answer 'how far is far enough,' we investigate the universal behavior of geographic diversity by exploring wind-speed correlations using three extensive datasets spanning continents, durations and time resolution. First, one year of five-minute wind power generation data from 29 wind farms span 1270 km across Southeastern Australia (Australian Energy Market Operator). Second, 45 years of hourly 10 m wind-speeds from 117 stations span 5000 km across Canada (National Climate Data Archive of Environment Canada). Finally, four years of five-minute wind-speeds from 14 meteorological towers span 350 km of the Northwestern US (Bonneville Power Administration). After removing diurnal cycles and seasonal trends from all datasets, we investigate dependence of correlation length on time scale by digitally high-pass filtering the data on 0.25–2000 h timescales and calculating correlations between sites for each high-pass filter cut-off. Correlations fall to zero with increasing station separation distance, but the characteristic correlation length varies with the high-pass filter applied: the higher the cut-off frequency, the smaller the station separation required to achieve de-correlation. Remarkable similarities between these three datasets reveal behavior that, if universal, could be particularly useful for grid management. For high

  18. Variability of interconnected wind plants: correlation length and its dependence on variability time scale

    SciTech Connect (OSTI)

    St. Martin, Clara M.; Lundquist, Julie K.; Handschy, Mark A.

    2015-04-02

    The variability in wind-generated electricity complicates the integration of this electricity into the electrical grid. This challenge steepens as the percentage of renewably-generated electricity on the grid grows, but variability can be reduced by exploiting geographic diversity: correlations between wind farms decrease as the separation between wind farms increases. However, how far is far enough to reduce variability? Grid management requires balancing production on various timescales, and so consideration of correlations reflective of those timescales can guide the appropriate spatial scales of geographic diversity grid integration. To answer 'how far is far enough,' we investigate the universal behavior of geographic diversity by exploring wind-speed correlations using three extensive datasets spanning continents, durations and time resolution. First, one year of five-minute wind power generation data from 29 wind farms span 1270 km across Southeastern Australia (Australian Energy Market Operator). Second, 45 years of hourly 10 m wind-speeds from 117 stations span 5000 km across Canada (National Climate Data Archive of Environment Canada). Finally, four years of five-minute wind-speeds from 14 meteorological towers span 350 km of the Northwestern US (Bonneville Power Administration). After removing diurnal cycles and seasonal trends from all datasets, we investigate dependence of correlation length on time scale by digitally high-pass filtering the data on 0.25–2000 h timescales and calculating correlations between sites for each high-pass filter cut-off. Correlations fall to zero with increasing station separation distance, but the characteristic correlation length varies with the high-pass filter applied: the higher the cut-off frequency, the smaller the station separation required to achieve de-correlation. Remarkable similarities between these three datasets reveal behavior that, if universal, could be particularly useful for grid management. For high

  19. Wind Power Curve Modeling in Simple and Complex Terrain

    SciTech Connect (OSTI)

    Bulaevskaya, V.; Wharton, S.; Irons, Z.; Qualley, G.

    2015-02-09

    Our previous work on wind power curve modeling using statistical models focused on a location with a moderately complex terrain in the Altamont Pass region in northern California (CA). The work described here is the follow-up to that work, but at a location with a simple terrain in northern Oklahoma (OK). The goal of the present analysis was to determine the gain in predictive ability afforded by adding information beyond the hub-height wind speed, such as wind speeds at other heights, as well as other atmospheric variables, to the power prediction model at this new location and compare the results to those obtained at the CA site in the previous study. While we reach some of the same conclusions at both sites, many results reported for the CA site do not hold at the OK site. In particular, using the entire vertical profile of wind speeds improves the accuracy of wind power prediction relative to using the hub-height wind speed alone at both sites. However, in contrast to the CA site, the rotor equivalent wind speed (REWS) performs almost as well as the entire profile at the OK site. Another difference is that at the CA site, adding wind veer as a predictor significantly improved the power prediction accuracy. The same was true for that site when air density was added to the model separately instead of using the standard air density adjustment. At the OK site, these additional variables result in no significant benefit for the prediction accuracy.

  20. JD Wind 6 Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    JD Wind 6 Wind Farm Jump to: navigation, search Name JD Wind 6 Wind Farm Facility JD Wind 6 Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner...

  1. JD Wind 7 Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    JD Wind 7 Wind Farm Jump to: navigation, search Name JD Wind 7 Wind Farm Facility JD Wind 7 Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner...

  2. Metro Wind LLC Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    Wind LLC Wind Farm Jump to: navigation, search Name Metro Wind LLC Wind Farm Facility Metro Wind LLC Sector Wind energy Facility Type Commercial Scale Wind Facility Status In...

  3. Michigan Wind II Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    II Wind Farm Jump to: navigation, search Name Michigan Wind II Wind Farm Facility Michigan Wind II Wind Farm Sector Wind energy Facility Type Commercial Scale Wind Facility Status...

  4. Garnet Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Garnet Wind Facility Garnet Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Azusa Light & Water...

  5. Lime Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Lime Wind Facility Lime Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Joseph Millworks Inc...

  6. Fairhaven Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Fairhaven Wind Facility Fairhaven Wind Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Solaya Energy Palmer...

  7. Scituate Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Scituate Wind Facility Scituate Wind Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Solaya Energy ...

  8. Pacific Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Pacific Wind Facility Pacific Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner enXco Developer...

  9. Galactic Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Galactic Wind Facility Galactic Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Epic Systems...

  10. Rockland Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Rockland Wind Facility Rockland Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Developer Ridgeline...

  11. Greenfield Wind | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name Greenfield Wind Facility Greenfield Wind Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Greenfield Wind Power...

  12. Willmar Wind | Open Energy Information

    Open Energy Info (EERE)

    Wind Jump to: navigation, search Name Willmar Wind Facility Willmar Wind Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Willmar...

  13. NREL: Innovation Impact - Wind

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

    Wind Energy Menu Home Home Solar Solar Wind Wind Analysis Analysis Bioenergy Bioenergy Buildings Buildings Transportation Transportation Manufacturing Manufacturing Energy Systems ...

  14. Energy 101: Wind Turbines

    ScienceCinema (OSTI)

    None

    2013-05-29

    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.

  15. Wind Program News

    SciTech Connect (OSTI)

    2012-01-06

    Stay current on the news about the wind side of the Wind and Water Power Program and important wind energy events around the U.S.

  16. Meteorological aspects of siting large wind turbines

    SciTech Connect (OSTI)

    Hiester, T.R.; Pennell, W.T.

    1981-01-01

    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.

  17. NREL: Wind Research - Site Wind Resource Characteristics

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

    Site Wind Resource Characteristics A graphic showing the location of National Wind Technology Center and its wind power class 2. Click on the image to view a larger version. ...

  18. A wind accretion model for HLX-1

    SciTech Connect (OSTI)

    Miller, M. Coleman; Farrell, Sean A.; Maccarone, Thomas J.

    2014-06-20

    The brightest ultraluminous X-ray source currently known, HLX-1, has been observed to undergo five outburst cycles. The periodicity of these outbursts, and their high inferred maximum accretion rates of ?few 10{sup 4} M {sub ?} yr{sup 1}, naturally suggest Roche lobe overflow at the pericenter of an eccentric orbit. It is, however, difficult for the Roche lobe overflow model to explain the apparent trend of decreasing decay times over the different outbursts while the integrated luminosity also drops. Thus, if the trend is real rather than simply being a reflection of the complex physics of accretion disks, a different scenario may be necessary. We present a speculative model in which, within the last decade, a high-mass giant star had most of its envelope tidally stripped by the ?10{sup 45} M {sub ?} black hole in HLX-1, and the remaining core plus low-mass hydrogen envelope now feeds the hole with a strong wind. This model can explain the short decay time of the disk, and could explain the fast decrease in decay time if the wind speed changes with time. A key prediction of this model is that there will be excess line absorption due to the wind; our analysis does in fact find a flux deficit in the ?0.9-1.1 keV range that is consistent with predictions, albeit at low significance. If this idea is correct, we also expect that within years to dacades the bound material from the original disruption will return and will make HLX-1 a persistently bright source.

  19. Speed control with end cushion for high speed air cylinder

    DOE Patents [OSTI]

    Stevens, Wayne W.; Solbrig, Charles W.

    1991-01-01

    A high speed air cylinder in which the longitudinal movement of the piston within the air cylinder tube is controlled by pressurizing the air cylinder tube on the accelerating side of the piston and releasing pressure at a controlled rate on the decelerating side of the piston. The invention also includes a method for determining the pressure required on both the accelerating and decelerating sides of the piston to move the piston with a given load through a predetermined distance at the desired velocity, bringing the piston to rest safely without piston bounce at the end of its complete stroke.

  20. High-Speed Photography

    SciTech Connect (OSTI)

    Paisley, D.L.; Schelev, M.Y.

    1998-08-01

    The applications of high-speed photography to a diverse set of subjects including inertial confinement fusion, laser surgical procedures, communications, automotive airbags, lightning etc. are briefly discussed. (AIP) {copyright} {ital 1998 Society of Photo-Optical Instrumentation Engineers.}

  1. NREL Develops New Controls that Proactively Adapt to the Wind (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-11-01

    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.

  2. NREL Develops New Controls that Proactively Adapt to the Wind (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-10-01

    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.

  3. NREL: Wind Research - Offshore Wind Turbine Research

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

    Offshore Wind Turbine Research Photo of a European offshore wind farm. Photo by Siemens For more than eight years, NREL has worked with the U.S. Department of Energy (DOE) to become an international leader in offshore wind energy research. NREL's offshore wind turbine research capabilities focus on critical areas that reflect the long-term needs of the industry and DOE. National Wind Technology Center (NWTC) researchers are perpetually exploring new wind and water power concepts, materials, and

  4. Full Hybrid: Low Speed

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    highlighted Cruising button Passing button Braking button Stopped button LOW SPEED For initial acceleration and slow-speed driving, as well as reverse, the electric motor uses electricity from the battery to power the vehicle. If the battery needs to be recharged, the generator starts the engine and converts energy from the engine into electricity, which is stored in the battery. stage graphic: vertical blue rule Main stage: See through car with battery, engine, generator, power split device,

  5. High-speed

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

    speed three-wave polarimeter-interferometer diagnostic for Madison symmetric torus B. H. Deng, D. L. Brower, and W. X. Ding Electrical Engineering Department, University of California, Los Angeles, California 90095 M. D. Wyman, B. E. Chapman, and J. S. Sarff Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 ͑Received 5 May 2006; presented on 10 May 2006; accepted 11 June 2006; published online 27 September 2006͒ A high-speed three-wave polarimeter-interferometer

  6. Wind | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Science & Innovation Energy Sources Renewable Energy Wind Wind Wind The United States is home to one of the largest and fastest growing wind markets in the world. To stay ...

  7. NREL: Wind Research - Wind Energy Videos

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

    Wind Energy Videos The National Wind Technology Center (NWTC) is pleased to offer video presentations of its world-class capabilities, facilities, research areas, and personnel. As ...

  8. NREL: Wind Research - Wind Resource Assessment

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

    Wind Resource Assessment A map of the United States is color-coded to indicate the high winds at 80 meters. This map shows the wind resource at 80 meters for both land-based and offshore wind resources in the United States. Correct estimation of the energy available in the wind can make or break the economics of wind plant development. Wind mapping and validation techniques developed at the National Wind Technology Center (NWTC) along with collaborations with U.S. companies have produced

  9. Wind Integration National Dataset (WIND) Toolkit

    Broader source: Energy.gov [DOE]

    For utility companies, grid operators and other stakeholders interested in wind energy integration, collecting large quantities of high quality data on wind energy resources is vitally important....

  10. Power Performance Test Report for the SWIFT Wind Turbine

    SciTech Connect (OSTI)

    Mendoza, I.; Hur, J.

    2012-12-01

    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.