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HomeMy WebLinkAboutDraft AWEA Small Wind Turbine Performance & Safety Standard, January 2009AWEA Standard AWEA 9.1 - 2009 ***DRAFT DOCUMENT*** AWEA Small Wind Turbine Performance and Safety Standard Approved by the AWEA Standards Coordinating Committee as a Draft Document for review by Materially Affected Parties 2009 January 08 a AMERICAN AWEA WIND ENERGY ASSOCIATION American Wind Energy Association 1501 M Street NW, Suite 1000 Washington, DC 20005 Page - | - AMERICAN WIND ENERGY ASSOCIATION STANDARDS Standards promulgated by the American Wind Energy Association (AWEA) conform to the AWEA Standards Development Procedures adopted by the AWEA Board of Directors. The procedures are intended to ensure that AWES standards reflect a consensus to persons substantially affected by the standard. The AWEA Standards Development Procedures are intended to be in compliance with the American National Standards Institute (ANSI) Essential Requirements. Standards developed under the AWEA Standards Development Procedures are intended to be eligible for adoption as American National Standards. AWEA standards may be revised or withdrawn from time to time. Contact AWEA to determine the most recent version of this standard. Published by: American Wind Energy Association 1501 M Street, NW, Suite 1000 Washington, DC 20005 202.383.2500 Copyright © 2009 American Wind Energy Association Attribution: No part of this standard may be reproduced or utilized in any form without proper attribution to the American Wind Energy Association. Credit should be acknowledged as follows: “AWEA Small Wind Turbine Performance and Safety Standard (AWEA Standard 9.1 — 2009) © The American Wind Energy Association.” Disclaimer AWEA Standards are developed through a consensus process of interested parties administered by the American Wind Energy Association. AWEA cannot be held liable for products claiming to be in conformance with this standard. Page - i - FOREWORD and BACKGROUND The Foreword and Background sections are included with this document for information purposes only, and are not part of the AWEA Small Wind Turbine Performance and Safety Standard. Foreword The goal of this standard is to provide meaningful criteria upon which to assess the quality of the engineering that has gone into a small wind turbine meeting this standard, and to provide consumers with performance data that will help them make informed purchasing decisions. The standard is intended to be written to ensure the quality of the product can be assessed while imposing only reasonable costs and difficulty on the manufacturer to comply with the standard. Background The proposed AWEA Small Wind Turbine Performance and Safety Standard that follows is in the final stages of approval by the AWEA Standards Coordinating Committee. AWEA is recognized by the American National Standards Institute (ANSI!) as an accredited standards writing body and the final standard will be an American National Standard. This standard has been developed in a regimented ANSI process for “voluntary consensus standards” which requires participation from a range of representatives for manufacturers, technical experts, public sector agencies, and consumers. The draft that follows has been developed over the last five years in a process that involved over 60 participants, three meetings, 22 hours of conference calls, countless e- mails, a list serve, and five intermediate drafts. It represents hundreds of hours of detailed discussion, debate, compromise, revision, and formal response. The Canadian Wind Energy Association has been actively involved since the beginning and the British Wind Energy Association has now adopted and approved this standard almost word for word. The proposed standard was developed by the AWEA Small Wind Turbine Standard Subcommittee, which is chaired by Mike Bergey of Bergey Windpower Co. Members of the subcommittee have included the following people. Please note that there has been some turnover in the subcommittee, some positions have changed, and not all members were active (though they did receive the drafts and correspondence). Page - ii - Name Affiliation Stakeholder Category Bill Colavecchio Underwriters Laboratory _| Certifying Agency Lex Bartlett Aeromag | Manufacturer David Blittersdorf Vermont Manufacturer / Consumer David Calley Southwest Windpower Manufacturer Jito Coleman Northern Power Manufacturer David Laino Endurance Manufacturer Robert Preus Abundant Ren. Energy _| Manufacturer Steve Turek Wind Turbine Industries Manufacturer Dr. Craig Hansen Windward Engineering | Technical Expert Robert Poore Global Energy Concepts Technical Expert Ken Starcher Alternate Energy Institute Technical Expert Trudy Forsyth National Renewable Energy Researcher / Technical Laboratory Expert Jim Green National Renewable Energy | Researcher / Technical Laboratory Expert Hal Link National Renewable Energy | Researcher / Technical Laboratory Expert Brian Vick _| USDA/Bushland Technical Expert Brent Summerville Appalachian State Univ. Technical Expert Alex DePillis Wisconsin Energy Office State Energy Office / Consumer Jennifer Harvey NYSERDA State Energy Office Cassandra Kling New Jersey BPU State Energy Office Dora Yen California Energy Comm. State Energy Office Paul Gipe California Consumer Mike Klemen North Dakota | Consumer Heather Rhoads Weaver Washington Consumer / AWEA Mick Sagrillo Wisconsin Consumer Brad Cochran Colorado Interested Party Samit Sharma Canada CanWEA Svend de Bruyn Detronics Canadian Industry Other participants in the development of this proposed standard have included (as they were affiliated at the time of their involvement): Mark Bastasch Ralph Belden, Synergy Power Michael Blair David Blecker, Seventh Generation Sandy Butterfield, NREL Bob Clarke, Ventera Energy Dean Davis, Windward Engineering John Dunlop, AWEA Page - iii - Henry DuPont, Lorax Mike Gray, Gray Engineering Jeffrey Haase, State of Minnesota Tod Hanley, Bergey Windpower Robert Hornung, CanWEA Arlinda Huskey, NREL Dale Jones, Geocorp Dan Juhl, DanMar Steve Kalland, NCSU Peter Konesky, State of Nevada Andy Kruse, Southwest Windpower Jean-Daniel Langlios Amy Legere, Southwest Windpower Malcomb Lodge, Entegrity Wind Charles Newcomb, Entegrity Wind Chuck Maas Dennis Makeperce, E.R.D. Tom Maves, State of Ohio Michael Mayhew Richard Michaud, US-DOE Jacques Michel, E.R.D. Paul Migliore, NREL Lawrence Mott, Earth Turbines Jennifer Oliver, Southwest Windpower Philippe Quinet Doug Selsam, Selsam Engineering David Sharman, Ampair / BVEA Robert Sherwin, Vermont Wind Power Int’! Larry Sherwood, IREC P.V. Slooten Eric Stephens Brian Smith, NREL Jeroen van Dam, NREL / UL David VanLuvanee Jane Weismann, IREC Kyle Wetzel, Consultant Sean Whittaker, CanWEA Page - iv - AWEA Small Wind Turbine Performance and Safety Standard Table of Contents Section Page 1. General Information 1 2. Performance Testing 3 3. Acoustic Sound Testing 6 4. Strength and Safety 6 5. Duration Test L 6. Reporting 7 7. Labeling 8 8. Changes to Certified Products 8 9. References and Appendices 9 Page - v - AWEA Small Wind Turbine Performance and Safety Standard Draft Standard Version 6.1 for adoption by the SCC (Version: 2008 October 13) 1 General Information 1.1. Purpose This standard was created by the small wind turbine industry, scientists, state officials, and consumers to provide consumers with realistic and comparable performance ratings and an assurance the small wind turbine products certified to this standard have been engineered to meet carefully considered standards for safety and operation. The goal of the standard is to provide consumers with a measure of confidence in the quality of small wind turbine products meeting this standard and an improved basis for comparing the performance of competing products. 1.2. Overview 1.2.1. This performance and safety standard provides a method for evaluation of wind turbine systems in terms of safety, reliability, power performance, and acoustic characteristics. This standard for small wind turbines is derived largely from existing international wind turbine standards developed under the auspices of the International Electrotechnical Commission (IEC). Specific departures from the IEC standards are provided to account for technical differences between large and small wind turbines, to streamline their use, and to present their results in a more consumer-friendly manner. 1.2.2 No indirect or secondary standards references are intended. Only standards directly referenced in this standard are embodied. 1.3. Scope 1.3.1 This standard generally applies to small wind turbines for both on-grid and off-grid applications. 1.3.2 This standard applies to wind turbines having a rotor swept area of 200 m2 or less. In a horizontal-axis wind turbine this equates to a rotor diameter of ~ 16 m (~ 52 ft) 1.3.3 A turbine system includes the wind turbine itself, the turbine controller, the inverter, if required, wiring and disconnects, and the installation and operation manual(s). 1.3.4 In cases where several variations of a turbine system are available, it is expected that a full evaluation would be performed on one of the most representative arrangements. Other variations, such as different power output forms, need only be evaluated or tested in the ways in which they are different from the base configuration. For example, a wind turbine Page - | - available in both grid-intertie and battery charging versions would need separate performance tests if both versions were to be certified, but would not need a separate safety evaluation in most cases. 1.3.5 Except as noted in Sections 2.1.1, 4.2, 5.2.5, 5.2.6, and 6.1.7.1, towers and foundations are not part of the scope of this standard because it is assumed that conformance of the tower structure to the International Building Code, Uniform Building Code or their local equivalent will be required for a building permit. 1.4 Compliance 1.4.1 Certification to this standard shall be done by an independent certifying agency. Self-certification is not allowed. 1.4.2 It is the intent of this standard to allow test data from manufacturers, subject to review by the certifying agency. 1.4.3. Compliance with this standard for the purposes of advertising or program qualification, or any other purpose, is the responsibility of the manufacturer. 1.5 Definitions 1.5.1 Definitions contained in IEC 61400-121, ed.1 (Performance); IEC 61400- 11 (Acoustic Noise); and IEC 61400-2, Ed. 2 (Design Requirements) are hereby incorporated by reference. 1.5.2 Additional Definitions 1.5.2.1 | AWEA Rated Power: The wind turbine’s power output at 11 m/s (24.6 mph) per the power curve from IEC 16400-121. 1.5.2.2 | AWEA Rated Annual Energy: The calculated total energy that would be produced during a one-year period at an average wind speed of 5 m/s (11.2 mph), assuming a Rayleigh wind speed distribution, 100% availability, and the power curve derived from IEC 16400-121 (sea level normalized). 1.5.2.3. AWEA Rated Sound Level: The sound level that will not be exceeded 95% of the time, assuming an average wind speed of 5 m/s (11.2 mph), a Rayleigh wind speed distribution, 100% availability, and an observer location 60 m (~ 200 ft.) from the rotor center’, calculated from IEC 61400-11 test results, except as modified in Section Ill of this Standard. 1.5.2.4 Cut-in Wind Speed: The lowest wind speed at which a wind ' Appendix A contains guidance on obtaining sound levels for different observer locations and background sound levels. Page - 2 - 1.6 1.7 turbine will begin to have power output”. 1.5.2.5 | Cut-out Wind Speed: The wind speed above which, due to control function, the wind turbine will have no power output. 1.5.2.6 Maximum Power: The maximum one-minute average power output a wind turbine in normal steady-state operation will produce (peak instantaneous power output can be higher). 1.5.2.7. Maximum Voltage: The maximum voltage the wind turbine will produce in operation including open circuit conditions. 1.5.2.8 | Maximum Current(s): The maximum current(s) the wind turbine will produce on each side of the systems control or power conversion electronics. 1.5.2.9 Overspeed Control: The action of a control system, or part of such system, which prevents excessive rotor speed. 1.5.2.10 Power Form: Physical characteristics which describe the form in which power produced by the turbine is made deliverable to the load. 1.5.2.11 Rotor Swept Area: Projected area perpendicular to the wind direction swept by the wind turbine rotor in normal operation (un-furled position). If the rotor is ducted, the area inscribed by the ducting shall be included. 1.5.2.12 Turbulence Intensity: The standard deviation of 1-second wind speed data divided by the mean of 1-second wind speed data averaged over a period of 1-minute. Units 1.6.1 The primary units shall be SI (metric). The inclusion of secondary units in the English system is recommended [e.g., 10 m/s (22.4 mph)]. Test Turbine and Electronics 1.7.1. Tested wind turbines and their associated electronics shall conform to the specific requirements of the governing IEC wind generator standard for each test, but incorporating any amendments contained in this standard. Performance Testing Wind turbine performance shall be tested and documented in a test report per the latest edition of IEC 61400-121, but incorporating the additional guidance provided in this section. 2.1.1. In Section 2.1, Wind Turbine Generator System: When characterizing performance, the wind turbine generator system shall include the following components, as appropriate: the turbine; turbine tower; turbine controller, ? As determined per Section 2.1.6 Page - 3 - 2d 2.1.3 2.1.4 leo 2.1.6 Zalel 2.1.8 2.1.9 regulator, or inverter; wiring between the turbine and the load; transformer; and dump load. Power shall be measured at the connection to the load such that the losses in the complete wind turbine system are included. Battery banks are not considered to be part of the wind turbine system for battery-charging wind turbines, but they are considered to be part of the system for grid-connected wind turbines that incorporate a battery bank. Also in Section 2.1, Wind Turbine Generator System: The wind turbine shall be connected to an electrical load that is representative of the load for which the turbine is designed. Also in Section 2.1, Wind Turbine Generator System: The wind turbine shall be installed using the manufacturer's specified mounting system. If a wind turbine is not supplied with a specific mounting system, the generator should be mounted at a hub height of at least 10 meters. The total wire run length, measured from the base of the tower, must be at least 8 rotor diameters and the wiring is to be sized per the manufacturer's installation instructions. The cut-in wind speed is the first wind speed bin in the averaged power curve that is positive. Also in Section 2.1, Wind Turbine Generator System: The voltage regulator in a battery-charging system shall be capable of maintaining voltage at the connection of the turbine to the batteries within 10% of 2.1 volts per cell for lead acid batteries over the full range of power output of the turbine. The 1-minute average of the load voltage must be within 5% of 2.1 volts per cell for lead acid batteries to be included in the usable data set. In Section 2.2.1, Distance of meteorological mast: If it is more practical to mount the anemometer on a long boom that is connected to the turbine tower, a separate meteorological mast is not required. To minimize the potential for the wake from the anemometer, the wind vane and their mounting hardware to influence flow into a small rotor, all such components shall be located at least 3 meters away from any part of the rotor. In addition, the anemometer mounting should be configured to minimize its cross-sectional area above the level that is 1.5 rotor diameters below hub height. In Section 3.1, Electric power: Turbine output power shall be measured at the connection to the load. 2.1.10 In Section 3: In addition to electric power, voltage at the connection to the load shall be measured to ensure compliance with the requirements listed below. 2.1.11 In Section 3.4, Air density: The air temperature sensor and the air pressure sensor shall be mounted such that they are at least 1.5 rotor diameters below hub height even if such mounting results in a location Page - 4 - less than 10 m above ground level. 2.1.12 In Section 3.6, Wind turbine generator status: Monitoring of small wind turbine status is required only when the turbine controller provides an indication of turbine faults. 2.1.13 In Section 4.3, Data collection: Preprocessed data shall be of 1-minute duration. In Section 4.4, Data reduction: Select data sets shall be based on 1-minute periods. 2.1.14 In Section 4.6, Database: The database shall be considered complete when it has met the following criteria: 2.1.14.1 Each wind speed bin between 1 m/s below cut-in and 14 m/s shall contain a minimum of 10 minutes of sampled data. 2.1.14.2 The total database contains at least 60 hours of data with the small wind turbine operating within the wind speed range. 2.1.14.3 The database shall include 10 minutes of data for all wind speeds at least 5 m/s beyond the lowest wind speed at which power is within 95% of Maximum Power (or when sustained output is attained). 2.1.15 In Section 5.1, Data normalization: For turbines with passive power control such as furling or blade fluttering, the power curve shall be normalized using Equation 5 (wind speed adjustment), Equation 6 (power adjustment), or an alternate method. Documentation must be provided to justify the use of an alternate method. 2.1.16 In Section 5.3, Annual energy production (AEP): In cases where the small wind turbine does not shut down in high winds, AEP measured and AEP projected shall be calculated as though cut-out wind speed were the highest, filled wind speed bin or 25 m/s, whichever is greater. 2.1.17 In Section 6, Reporting format: In addition to the information listed in clause 6, the description of the wind turbine and the test set-up shall include: 2.1.17.1 wiring sizes, conductor material, types, lengths and connectors used to connect the wind turbine to the load; 2.1.17.2 measured resistance of wiring between the inverter and the load or between the turbine and the load if no inverter is used; 2.1.17.3 voltage setting(s) for any over or under-voltage protection devices that are part of the small wind turbine generator system; 2.1.17.4 nominal battery bank voltage (e.g., 12, 24, 48 volts); 2.1.17.5 battery bank size (i.e., amp-hour capacity), battery type and age; and 2.1.17.6 description including make, model, and specifications of the voltage regulation device used to maintain the battery bank Page - 5 - 2.2 voltage within specified limits. The Performance Test Report shall include the turbulence intensity for each data set (Sequential, unbroken, time series) so that the reviewers can pass judgment on the appropriateness of the test site. 3 Acoustic Sound Testing 3.1 Wind turbine sound levels shall be measured and reported in accordance with the latest edition of IEC 61400-11 2002-12, but incorporating the additional guidance provided in this section. 3.1.1. The averaging period shall be 10 second instead of 1 minute. 3.1.2 Measuring wind speed directly instead of deriving wind speed through power is the preferred method. 3.1.3. The method of bins shall be used to determine the sound pressure levels at integer wind speeds. 3.1.4 It shall be attempted to cover an as wide a wind speed range as possible, as long as the wind screen remains effective. 3.1.5 A description shall be provided of any obvious changes in sound at high wind speeds where overspeed protection becomes active (like furling, pitching or fluttering). 3.1.6 A tonality analysis is not required, but the presence of prominent tones shall be observed and reported. 4 Strength and Safety 4.1 4.2 4.3 Except as noted below, mechanical strength of the turbine system shall be assessed using either the simple equations in Section 7.4 of IEC61400-2 ed2 in combination with the safety factors in Section 7.8, or the aeroelastic modeling methods in the IEC standard. Evaluation of, as a minimum, the blade root, main shaft and the yaw axis (for horizontal axis wind turbines) shall be performed using the outcome of these equations. A quick check of the rest of the structure for obvious flaws or hazards shall be done and if judged needed, additional analysis may be required. Variable speed wind turbines are generally known to avoid harmful dynamic interactions with towers. Single/dual speed wind turbines are generally known to have potentially harmful dynamic interactions with their towers. Therefore, in the case of single/dual speed wind turbines, such as those using either one or two induction generators, the wind turbine and tower(s) must be shown to avoid potentially harmful dynamic interactions. A variable speed wind turbine with dynamic interactions, arising for example from control functions, must also show that potentially harmful interactions are likewise avoided. Other safety aspects of the turbine system shall be evaluated including: Page - 6 - 4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 procedures to be used to operate the turbine; provisions to prevent dangerous operation in high wind; methods available to slow or stop the turbine in an emergency or for maintenance; adequacy of maintenance and component replacement provisions; and susceptibility to harmful reduction of control function at the lowest claimed operating ambient temperature. 4.4 A Safety and Function Test shall be performed in accordance with Section 9.6 of IEC61400-2 ed2. 5 Duration Test 5.1. To establish a minimum threshold of reliability, a duration test shall be performed in accordance with the IEC 61400-2 ed.2 Section 9.4. 5.2. Changes and additional clarifications to this standard include: S201 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6 The test shall continue for 2500 hours of power production. The test must include at least 25 hours in wind speeds of 15 m/s (33.6 mph) and above. Downtime and availability shall be reported and an availability of 90% is required. Minor repairs are allowed, but must be reported. If any major component such as blades, main shaft, generator, tower, controller, or inverter is replaced during the test, the test must be restarted. The turbine and tower shall be observed for any tower dynamics problems during the duration test and the test report shall include a statement of the presence or absence of any observable problems 6 Reporting and Certification 6.1 The test report shall include the following information: 6.1.1 6.1.2 6.1.3 6.1.4 6.1.5 Summary Report, containing a power curve, an Annual Energy Production curve, and the measured sound pressure levels (Section 9.4 of IEC 61400-11 ed.2). The report is intended to be publicly available once approved by the certifying agency. Performance Test Report Acoustic Test Report The AWEA Rated Annual Energy The AWEA Rated Sound Level Page - 7 - 6.1.6 The AWEA Rated Power, at 11 m/s (24.6 mph) 6.1.7 Wind Turbine Strength and Safety Report 6.1.8 The tower top design loads shall be reported 6.1.9 Duration Test Report 6.2 The manufacturers of certified wind turbines must abide by the labeling requirements of the certifying agency. 7 Labeling 7.4 7.2 7.3 74 The AWEA Rated Annual Energy (AWEA RAE) shall be stated in any label, product literature or advertising in which product specifications are provided. 7.1.1. The AWEA RAE shall be rounded to no more than 3 significant figures. The manufacturer shall state the AWEA Rated Power if a rated power is specified. The manufacturer shall state the AWEA Estimated Sound Level if a sound level is specified. Other performance data recommended to be stated in specifications about the turbine are: 7.4.1 Cut-in Wind Speed 7.4.2 Cut-out Wind Speed 7.4.3, Maximum Power 7.4.4 Maximum Voltage 7.4.5 Maximum Current(s) 7.4.6 Overspeed Control 7.4.7 Power Form 8 Changes to Certified Products 8.1 It is anticipated that certified wind turbines will occasionally be changed to provide one form of improvement or another. In some cases such changes will require review by the certifying agency and possible changes to the certified product parameters. The following guidance is provided concerning when product changes will require certifying agency review: 8.1.1. Any changes to a certified wind turbine that will have the cumulative effect of reducing AWEA Rated Power or AWEA Rated Annual Energy by more than 10%, or that will raise the AWEA Rated Sound Level by more than 1 Page - 8 - 8.2 8.3 dBA will require retesting and recertification by the certifying agency. Only those characteristics of the wind turbine affected by the design change(s) would be reviewed again. 8.1.2 Any changes to a certified wind turbine that could reduce the strength and safety margins by 10%, or increase operating voltages or currents by 10%, will require resubmission of the Wind Turbine Strength and Safety Report and recertification by the certifying agency. 8.1.3 Any changes to a certified wind turbine that could materially affect the results of the Duration Test will require retesting, submission of a new Duration Test Report, and recertification by the certifying agency. For the first two years after turbine certification the manufacturer is required to notify the certifying agency of all changes to the product, including hardware and software. The certifying agency will determine whether the need for retesting and additional review under the guidelines provided in Section 8.1. The use of Engineering Change Orders or their equivalent is recommended. 9 References and Appendices 9.1 References 9.1.1 Evaluation Protocol for Small Wind Systems, Rev. 3. NREL internal document. 9.1.2 IEC 61400-121 Ed. 1, Wind Turbines — Part 121: Power performance measurement of grid connected wind turbines. 9.1.3 IEC 61400-11, Second Edition 2002-12, Wind turbine generator systems - Part 11: Acoustic noise measurement techniques. 9.1.4 IEC 61400-2, Ed. 2, Wind turbine generator systems — Part 2: Design requirements of small wind systems. Page - 9 - Appendix A Sound Levels for Different Observer Locations and Background Sound Levels The AWEA Rated Sound Level is calculated at a distance of 60 meters from the rotor hub and excludes any contribution of background sound. As the distance from the turbine increases, the background sound becomes more dominant in determining the overall sound level (turbine plus background). Background sound levels depend greatly on the location and presence of roads, trees, and other sound sources. Typical background sound levels range from 35dBA (quiet) to 50dB(A) (urban setting) Equation 1 can be used to calculate the contribution of the turbine to the overall sound level using the AWEA Rated Sound Level. Equation 2 can be used to add the turbine sound level to the background sound level to obtain the overall sound level. turbine sound level = L gycc +10 log(47607) — 10 log(4zk? ) (1) Where: Lawea is the SWW Rated Sound Level [dBA]. R is the observer distance from the turbine rotor center [m] turbine level background level overall sound level =10log(10 " +10 ” ) (2) Table 1 Overall Sound Levels at Different Locations for a AWEA Rated Sound Level of 40 dBA Distance Lawea: 40dBA from rotor background noise level (dBA): | center [m] | 30 35 40 45 50 10. | 556 | 556 | 557 | 559 | 566 20 496 | 497 | 500 | 509 | 528 30 46.1 | 464 | 47.0 | 486 | 51.5 40 43.7 | 44.1 | 451 | 47.3 | 509 50 41.9 | 424 | 439 | 466 | 506 60 404 | 41.2 | 430 | 462 | 504 70 39.2 | 402 | 424 | 459 | 503 80 38.2 | 394 | 419 | 45.7 | 502 100 36.6 | 383 | 413 | 45.5 | 502 150 34.1 | 368 | 406 | 45.2 | 50.1 200 32.8 | 361 | 40.4 | 451 | 50.0 Table 2 Overall Sound Levels at Different Locations for a AWEA Rated Sound Level of 45 dBA Distance Lawea: 45dBA from rotor background noise level (dBA): center [m] | 30 35 40 45 50 10 60.6 60.6 60.6 60.7 60.9 20 54.6 54.6 54.7 55.0 55.9 30 §1.1 51.1 51.4 52.0 53.6 40 48.6 48.7 49.1 50.1 52.3 50 46.7 46.9 47.4 48.9 51.6 60 45.1 45.4 46.2 48.0 51.2 70 43.8 44.2 45.2 47.4 50.9 Page - | - for a AWEA Rated Sound Level of 50 dBA for a AWEA Rated Sound Level of 55 dBA 80 42.7 43.2 44.4 46.9 50.7 100 40.9 41.6 43.3 46.3 50.5 150 37.8 39.1 41.8 45.6 50.2 200 35.9 37.8 41.1 45.4 50.1 Table 3 Overall Sound Levels at Different Locations Distance Lawea: 50dBA from rotor background noise level (dBA): center [m] | 30 35 40 45 50 10 65.6 65.6 65.6 65.6 65.7 20 59.5 59.6 59.6 59.7 60.0 30 56.0 56.1 56.1 56.4 57.0 40 53.5 53.6 53.7 54.1 55.1 50 51.6 51.7 $1.9 52.4 53.9 60 50.0 50.1 50.4 $1.2 53.0 70 48.7 48.8 49.2 50.2 52.4 80 47.6 47.7 48.2 49.4 51.9 100 45.7 45.9 46.6 48.3 51.3 150 42.3 42.8 44.1 46.8 50.6 200 40.0 40.9 42.8 46.1 50.4 Table 4 Overall Sound Levels at Different Locations Distance Lawea: SSdBA from rotor background noise level (dBA): center [m] |~30 35 40 45 50 10 70.6 70.6 70.6 70.6 70.6 20 64.5 64.5 64.6 64.6 64.7 30 61.0 61.0 61.1 61.1 61.4 40 58.5 58.5 58.6 58.7 59.1 50 56.6 56.6 56.7 56.9 57.4 60 55.0 55.0 55.1 55.4 56.2 70 53.7 53.7 53.8 54.2 55.2 80 52.5 52.6 52.7 53.2 54.4 100 50.6 50.7 50.9 51.6 53.3 150 47.1 47.3 47.8 49.1 51.8 200 44.7 45.0 45.9 47.8 51.1 Page - 2 - Overall Sound level (dBA] oO 20 40 60 80 100 120 140 160 180 200 Distance from rotor center [m] Figure 1. Sound levels as a function of distance and background noise levels for AWEA rated sound level of 40dB(A) 65 a a Overall Sound level [dBA] 8 - a 35 0 20 40 60 80 100 120 140 160 180 200 Distance from rotor center [m} Figure 2 Sound levels as a function of distance and background noise levels for AWEA rated sound level of 45dB(A) Page - 3 - Overall Sound level (dBA) 0 20 40 60 80 100 120 140 160 180 200 Distance from rotor center [m] Figure 3 Sound levels as a function of distance and background noise levels for AWEA rated sound level of 50dB(A) 75 70 & g & Overall Sound level [dBA] g 45 oO 20 40 60 80 100 120 140 160 180 200 Distance from rotor center [m] Figure 4 Sound levels as a function of distance and background noise levels for AWEA rated sound level of 55dB(A) Page - 4-