Ordinance On Noise From Wind Turbines

Original Language Title: Bekendtgørelse om støj fra vindmøller

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Overview (table of contents)



Chapter 1



Scope and definitions





Chapter 2



Requirements for wind turbines





Chapter 3



Experimental m





Chapter 4



Review, etc.





Chapter 5



Supervision, and notices about the noise measurements





Chapter 6



Complaint and punishment





Chapter 7



Entry into force of the





Annex 1









The full text of the Ordinance on noise from wind turbines

Under section 7 (1) (8). 1 and 2, section 7 a, paragraph 1, section 92 and section 110, paragraph 3, of the law on environmental protection, see. lovbekendtgørelse nr. 879 of 26. June 2010, and section 33, paragraph 1, article 48, paragraph 1, and section 61 (1) of the law on the protection of the marine environment, see. lovbekendtgørelse nr. 929 of 24. September 2009, as amended by section 1 of Act No. 423 of 10. May 2011 be fixed: Chapter 1 scope and definitions article 1. The Ordinance shall apply to the establishment, modification and operation of wind turbines.

§ 2. For the purposes of this order: 1) Small wind turbines: individual wind turbines with a rotor area of 200 m2 or less and with a total height of 25 meters or less, including household m.

2 m: The first Prototype), not mass-produced wind turbine of a new type.

3) Series 0-m: First, smaller production series of a new type of wind turbine.

4) Experimental turbines: Series O-m or wind turbines that are certified or converted for use for prototype testing in accordance with Executive order on the technical authentication scheme for the design, manufacture, erection, maintenance and service of wind turbines.

5) wind farm: a collection of 3 or more wind turbines.

6) Noise impact area around experimental turbines: The largest extent of the area surrounding the experimental m where the total noise from wind turbines is higher than 37 dB (A) 6 m/s and 39 DB(a) at 8 m/s, determined in accordance with the guidelines set out in annex 1.

7) noise sensitive land use: Areas used for or in the local plan or urban statute is zoned for residential, institutional, cottage-camping-or allotment garden purposes, or areas that are zoned in local plan or urban regulations for noise sensitive recreational activity.

8) low-frequency noise: Noise in the frequency range from 10 to 160 Hz. Low frequency noise are characterized by the A-weighted level of noise in 1/3-octave bands from 10 to 160 Hz, calculated indoor using the method set out in annex 1.

Chapter 2 section 3 Requirements for wind turbines. The person who owns a wind turbine, is responsible for the fact that the established, operated and maintained in such a way that the provisions of this Ordinance are complied with.

§ 4. The total noise exposure from wind turbines shall not exceed the following limits: 1) in the most noise loaded point at outdoor living areas up to a maximum of 15 metres from the flat in the open country: a) 44 dB (A) at a wind speed of 8 m/s.

(b)) 42 DB(a) at a wind speed of 6 m/s.

2) in the most congested point in areas of noise for noise sensitive land uses: a) 39 DB(a) at a wind speed of 8 m/s.

b) 37 dB (A) at a wind speed of 6 m/s.

(2). The overall low-frequency noise from wind turbines must be indoor in living quarters in the open country or indoors in areas of noise sensitive land uses do not exceed 20 dB at a wind speed of 8 m/s and 6 m/s.

(3). The limit values set out in paragraphs 1 and 2 shall not apply to the wind turbine owner's living quarters.

§ 5. Noise pollution, see. section 4, paragraphs 1 and 2, shall be determined in accordance with the guidelines set out in annex 1 and is indicated as the equivalent, corrected, the A-weighted noise level of the 1.5 m height at wind speeds adjusted to 10 meters altitude on respectively 6 m/s and 8 m/s at a roughness length on 0.05 m.

§ 6. Measurement of wind turbines the source strength of tone and content of the noise is carried out in accordance with the instructions in annex 1 as "Environmental measurement-external noise", see. Ordinance on the quality requirements for environmental measurements.

(2). Measurements on wind turbines, which are equipped with more generators, add noise broadcast from the wind turbine during operation with the generator, which causes the highest total noise removal, as a basis for sound measurements.

Chapter 3 Test m § 7. Habitation, etc., entered or be provided in existing buildings within a noise impact area around experimental turbines after the time of publication of draft local plan, which expounds the area to erect experimental wind turbines, is irrelevant for the assessment of noise from exploratory m, see. However, paragraph 2.

(2). Habitation, etc., entered or be provided in existing buildings within a noise impact area around experimental turbines at sea after the time of the publication of the EIA are immaterial for the assessment of noise from these.

(3). When windmills desired established or changed outside of an area zoned for experimental turbines on land or outside of an area of the sea where the Danish Energy Agency has authorized the establishment of experimental turbines in the meaning of section 25 of the Act on the promotion of renewable energy, the total noise contributions from experimental wind turbines, which are used to test the turbines ' noise impact area, taken into account for the assessment of If noise limits given in clause 4 (1) and (2) are complied with. The same applies for the purpose of supervision of these wind turbines.

Chapter 4 Review, etc.

§ 8. Anyone who wants to set up a wind turbine or modify it in a way which might result in increased noise removal, must submit a notification to this effect to the Municipal Council. However, this does not apply for the establishment or modification of the wind turbines at sea.

(2). The notification must contain evidence that wind turbines can comply with the noise limits given in clause 4.

(3). Documentation must be provided in the form of: 1) a report of measurements of noise broadcast from one or more copies of the proposed wind turbine type, see. § 6.

2) Card material over the area where the competent authority or notified windmills desired established. Map material must be provided with scale and North arrow and carefully set the placement of wind turbines declared sites, location of existing wind turbines as well as settlements and the distance to here and to other noise sensitive land uses.

3) calculation of noise pollution by the points mentioned in paragraph 4 in accordance with the guidelines in annex 1.

(4). For prototype wind turbines must be the subject of such measurements and calculations in accordance with paragraph 3, no. 1 that the probability can be made that the Windmill will be able to comply with the noise limits.

§ 9. The notification shall be deemed to be filed until the Municipal Council have received all those in section 8 (3) of the said information. Review may not happen when there is the necessary level basis and any fact that permission and EIA permit for the wind turbine, see. notice on the assessment of the effects of certain public and private fixed effect on the environment.

(2). The Municipal Council has not within 4 weeks from the date specified in paragraph 1 objected, the turbine is established or modified, unless other laws to the contrary.

(3). Construction workers may not commence before 4 weeks of expiry of the deadline, unless the local authority before then announces that it will not object to the notification.

(4). In those areas, according to the municipality or local planning is reserved for the erection of several wind turbines or zoned to the wind farm, and where the notification is done sequentially by individual wind turbines, can the local authority to ensure that the total noise contribution from all the wind turbines in these areas comply with the noise limits in section 4, put more stringent requirements for contribution from the individual wind turbine noise than noise limits in section 4.

§ 10. When a wind turbine after creation or modification brought into service, it shall be notified to the local authority, It does not however apply to wind turbines at sea, where the message needs to be given to the environmental protection agency.

(2). Is a declared windmill is not put into operation within two years after the expiry of the period laid down in article 9, paragraph 2, new review with those in section 8, paragraph 3, the specified information shall be submitted to the Municipal Council.

Chapter 5 monitoring and injunctive relief concerning noise measurements section 11. The Municipal Council responsible for supervising compliance with this Decree, without prejudice. However, paragraph 2.

(2). The environmental protection agency oversees compliance with this Ordinance in the case of wind turbines at sea.

§ 12. The Municipal Council may order that the owner of a wind turbine at its own expense, carry out noise measurements and calculations, see. sections 5 and 6, 1) when a pending wind turbine put into operation, 2) in connection with General oversight by law, however, no more than once annually, or 3) in connection with the treatment of neighbor complaints about noise, when the Municipal Council considers this to be necessary.

(2). The Municipal Council may in connection with the monitoring of small wind turbines provide that noise measurements should not be executed as "Environmental measurement-external noise", see. section 6 (1).

(3). Paragraphs 1 and 2 shall not apply to wind turbines at sea.

Chapter 6 Complaint and punishment section 13. Apart from decisions pursuant to section 12 and all decisions related to municipally owned or municipally-run wind turbines may not be appealed to other decisions of the Board of Directors municipal administrative authority.

§ 14. Unless a higher penalty is inflicted upon the rest of the legislation, is punishable by a fine anyone who 1) establishes a windmill or change it in a way that can cause increased noise removal, without notification and proper documentation, see. section 8,


2) commences construction works or sets up a wind turbine, regardless of opposition from the local authority, see. § 9, paragraph 2 or 4, 3) commencing construction works in contravention of section 9 (3), (4)) put a wind turbine in operation in violation of § 10, or 5) fails to comply with an obligation under section 12.

(2). The penalty can rise to imprisonment for up to 2 years if the infringement was committed intentionally or through gross negligence, and if the infringement is 1) caused damage to the environment or caused danger therefore or 2) achieved or intended an economic advantage for the person himself or others, including savings.

(3). That can be imposed on companies, etc. (legal persons) criminal liability in accordance with the provisions of the criminal code 5. Chapter.

Chapter 7 entry into force of section 15. The notice shall enter into force on the 1. January 2012.

(2). § 7 shall apply for the experimental turbines, where the EIA for windmills at sea or the draft local plan, which expounds the area to erect experimental wind turbines, is published on 1 December. January 2012 or later.

(3). Is a wind turbine notified under the existing rules in the 1. January 2012, but not put into operation within two years after the expiry of the opposition period, the Board of Directors municipal new notification shall be submitted to the Municipal Council in accordance with this Ordinance in section 8 (3) of the specified information. It does not apply to wind turbines at sea.

(4). Executive Order No. 1518 of 14. December 2006 about noise from wind turbines is repealed, but shall continue to apply for wind turbines, which are notified or put into operation before the 1. January 2012.

(5). Executive Order No. 304 of 14. May 1991 on noise from wind turbines continues to apply for wind turbines, which are notified or put into operation before 1. January 2007.

The Ministry of the environment, the 15. December 2011 Ida Auken/Claus T. ...



Annex 1 Section 1

1.1. General rules for the measurement of noise broadcast from a wind turbine

Measure the position of the country placed wind turbines

A wind turbine noise removal (sound power level LWA in 1/3-or 1/1 octave band) are measured in different ranges of wind turbine produced electric power at a point in the Lee side of the tower. To be measured at a distance R from the wind turbine's foot, which shall not exceed ± 20% of the distance R0 (see Figure 1), at the same time, the deviation from R0 not exceed ± 30 metres. Distance R0 is the wind turbine hub height (h) plus rotor radius (½ d). For a vertical axle windmill is the distance R0 in place the height to the center of the rotor plus cross-goal of the element rotates about its vertical axis; This is not illustrated.



Figure 1.

During the measurement the microphone must be positioned so that the direction of the wind turbine tower for microphone ± 15 ° from the wind direction.

On the basis of lydmålingerne A-weighted reference Spectra determined by wind speeds of 6 m/s and 8 m/s, respectively.

Microphone attached to ½ wind hood and placed directly on top of a reflective plate on the ground to eliminate wind noise in microphone as far as possible. The plate must not in any context be less than 1 meter. By measuring the noise broadcast at low frequencies can wind give excessive background noise. It can be counteracted by taking advantage of a secondary wind screen which is semicircular, between 40 and 50 cm in diameter or larger, and positioned concentric over microphone and wind hood. Using the secondary wind screen must be corrected for the attenuation of the sound, as the screen causes. The correction to be made in 1/3-octave band.

Measurement of lydspektre and wind speed

The noise from the wind turbine is measured as A-weighted lydspektre per 1/3-octave in a frequency range covering at least 1/3-octave bands from 20 to 10,000 Hz. Measured a number of lydspektre in the periods, which shall be at 10 or 60 seconds, and where, during the same period, recorded both wind turbine produced electrical mean power, the wind speed measured with the wind turbine hub height wind sensor built-in, and also with a wind sensor which shall be drawn up in at least 10 m altitude near the turbine in a place where neither the turbine or objects in the terrain are estimated to affect wind measurements.

When the wind turbine electrical mean power produced is less than 0.95 times its nominal power, the wind speed vh in turbine hub height is calculated from the turbine power curve. Wind speed vref for 10 meters height under reference conditions can then be determined using Equation 1.1.1. At higher produced effect is determined wind speed vh in the turbine hub height instead through the use of built-in wind turbine hub height wind sensor, and wind speed vref is determined using Equation 1.1.1. If the wind turbine power curve, exceptionally, is not known, or when the turbine is stopped because the measured background noise, the wind speed is determined by using the set wind sensor for at least 10 m height. Wind speed vref is determined using equation then 1.1.2.

On the basis of all measurements with the turbine is operating with produced mean power less than 0.95 times the rated power, established the connection between the wind speed, which is read from the turbine power curve and converted to vref, and respectively the wind speed measured with the wind turbine hub height wind gauge built and converted to vref, and wind speed, measured with the set for at least 10 m height wind sensor and converted to vref , in the following way. For each measurement period of 10 or 60 seconds is determined the relationship between the wind speed, which is read from the turbine power curve and the two measured wind speeds separately, and finally determined the mean of all conditions for each of the two wind gauges. These average values have to be multiplied on readings from respectively. wind turbine hub height wind sensor, built when the mean power produced is more than 0.95 times the nominal power, and on the reading from the anemometer for at least 10 m height, when the turbine is stopped and measured background noise. Thus carried out an in situ calibration of turbine built-in anemometer and of the anemometer. Because of the wind turbine power curve is used to establish the correlation between the produced effect and wind speed, a copy of the power curve included in the report if the source strength measurements.

Using a midlingsperiode of 10 seconds must be measured at least 30 Spectra by means of electrical effects, similar to the wind speed vref for 10 meters height under reference conditions is situated in the range 5.5 m/s ≤ vref ≤ 6.5 m/s and at least 30 Spectra where vref equivalent is located in the range of 7.5 m/s ≤ vref ≤ 8.5 m/s. By a midlingsperiode in 60 seconds can measured proportionally fewer spectra in each of the two intervals. Of the above-mentioned Spectra must be at least 12 of the Spectra (at a midlingsperiode in 10 seconds) lie in the following four ranges for vref:

5.5 m/s ≤ vref < 6.0 m/s

6.0 m/s ≤ vref ≤ 6.5 m/s

7.5 m/s ≤ vref < 8.0 m/s

m/s ≤ vref ≤ 8.0 8.5 m/s

The A-weighted reference spectrum by respectively 6 m/s and 8 m/s for each 1/3-octave bands (or 1/1 octave band) then determined as the mean value of the measured energy spectra for vref located in the said intervals around 6 m/s and 8 m/s, respectively.



Equation 1.1.1. Correction of wind speed measured in wind turbine hub height to 10 m height.

If the wind speed is measured in height z, is the relationship between vref and vz given by equation 1.1.2.



Equation 1.1.2. Correction of wind speed measured with established anemometer height z to 10 m height.











Terrain type









Roughness z0 [meter]









Water, snow, sand





0.0001







Open flat landscape, bare ground, trimmed lawns





0.01







Agricultural land with vegetation





0.05







Villa quarter, smaller cities, areas with dense, high stand





0.3











Table 1.1: Roughness of different terrain types of correction for background noise, the determination of the sound power level

With the Windmill stopped measured background noise as a corresponding number of lydspektre and at the same intervals of wind speeds as above stated. Wind speed is measured using an established anemometer for at least 10 m elevation, and wind speed vref is calculated using Equation 1.1.2.

Energy mean value of the measured background noise spectra at 6 m/s and 8 m/s, respectively, and used for correction of turbine reference spectrum, where the sound pressure levels LA, ref in each 1/3-octave bands (or 1/1 octave band) in the reference spectrum shall be corrected in accordance with equation 1.1.3. If not the sound pressure level in the reference spectrum is at least 3 dB higher than the sound pressure level of the background noise, to correction for background noise should be limited to 3 dB.


The total level LAeq by the midlede background noise must be at least 6 dB lower than the total level LAeq of wind noise. This is not the case, a new measurement is carried out when the background noise is lower. In connection with the control of noise pollution may be used, where the difference between the total noise measurements and background noise is less than 6 dB if the calculated noise level after a correction for background noise on 1.3-dB is not higher than the limit values.



Equation 1.1.3. Correction for background noise

Turbine sound power level LWA, ref in 1/3-octave bands (or 1/1 octave band) exists then with equation 1.1.4.



Equation 1.1.4. Wind turbine sound power level

The procedure described is in general accordance with IEC 61400-11, and measurements carried out in accordance with the standard can be used as a basis for determination of the LWA, ref.

1.2. determination of the sound pressure level LpA

At one point, URf.eks. by nearest neighbor, may the wind turbine A-weighted sound pressure level in 1/3-octave bands (or 1/1 octave band) in 1.5 m height is determined by equation 1.2.1.



Equation 1.2.1. Calculation of sound pressure level in 1/3-octave bands (or 1 (1-octave bands)

The calculations are carried out for 1/3-octave bands 50 Hz-10,000 Hz or 1/1 octave bands 63 Hz-8000 Hz.











Octave band center frequency in Hz









63









125









250









500









1000









2000









4000









8000









αa in dB/km





0.11





0.38





1.02





2.0





3.6





8.8





29.0





104.5











Table 1.2: Air absorption coefficients per 1/1-octave at a relative humidity of 80% and an air temperature of 10 ° C



1/3-octave center frequency in Hz









50









63









80









100









125









160









200









250









315









αa in dB/km





0.07





0.11





0.17





0.26





0.38





0.55





0.77





1.02





1.3





















1/3-octave center frequency in Hz









400









500









630









800









1000









1250









1600









2000









αa in dB/km





1.6





2.0





2.4





2.9





3.6





4.6





6.3





8.8





















1/3-octave center frequency in Hz









2500









3150









4000









5000









6300









8000









10000









αa in dB/km





12.6





18.8





29.0





43.7





67.2





105





157











Table 1.3: Air absorption coefficients per 1/3-octave at a relative humidity of 80% and an air temperature of 10 ° C It can be chosen to attribute a safety margin, so that in the calculations used higher numbers for source power LWA, ref, than it appears from the measuring report. The total A-weighted sound pressure level LpA, tot in point exists then by summing the sound pressure levels LpA, in each 1/3-octave bands (or 1/1 octave band), see. equation Equation 1.2.2 1.2.2. Total sound pressure level

Ubestemtheden on the calculated sound pressure level LpA, tot, using this approach are ± 2 dB.

1.3. determination of tones and noise load Lr

In order to be able to determine the noise load Lr in a given point to be abating content of clearly audible tones shall be assessed.


The assessment shall be carried out at the most noise loaded housing by objective measurement in accordance with the guidelines in Chapter 7 of the environmental protection agency's guidance on the measurement of environmental noise, no. 6/1984. Using the method must, however, it is assumed that the tones are stationary, so that both the level of the tones and the level of the masking noise shall be determined by calculating an average value of a number of Spectra, which corresponds to a time of the analysis of at least 1 minute, and frequency analyses must be carried out by A-weighted spectra.

The noise measurement shall be carried out in a representative point near the nearest dwelling, 1.5 m above the terrain and selected in such a way that wind noise gets the least possible impact on the measurement results.

There must be a tailwind ± 45 ° from the turbine toward the measure, and the wind speed measured 10 metres above the ground must be between 6 and 8 m/s. There must be measured in a time interval during which the tone is most evident.

In this context there is no requirement for temperature gradient or cloud cover.

If a frequency analysis of turbine noise, measured close to the turbine, as described in the procedures for the measurement of the A-weighted sound power level, shows that there does not seem to be clearly audible tones near the Windmill, there will be no tones in noise at habitation, and a separate analysis thereof is not necessary.

By a treatment of a notification tone content can be determined from a measurement of the tail-wind side of a similar wind turbine at a distance corresponding to the current distance to neighboring point.

Contains the noise clearly audible tones shall be determined as specified in equation Lr 1.3.1.



Equation 1.3.1. Determination of clearly audible tones

1.4. determination of low frequency noise from wind turbines

The level of low-frequency noise, URf.eks. in the nearest housing is determined by equation 1.4.1.



Equation 1.4.1. Calculation of low frequency noise from wind turbines in 1/3-octave bands 1/3-octave center frequency in Hz









10









12.5









16









20









25









31.5









40









∆ LgLF: terrain correction, country located windmill (dB)





6.0





6.0





5.8





5.6





5.4





5.2





5.0







∆ LgLF: terrain correction, offshore turbine (dB)





6.0





6.0





6.0





6.0





6.0





5.9





5.9







∆ Lσ: sound insulation (level differential) (dB)





4.9





5.9





4.6





6.6





8.4





10.8





11.4







αa in dB/km





0.0





0.0





0.0





0.0





0.02





0.03





0.05





















1/3-octave center frequency in Hz









50









63









80









100









125









160









∆ LgLF: terrain correction, country located windmill (dB)





4.7





4.3





3.7





3.0





1.8





0.0







∆ LgLF: terrain correction, offshore turbine (dB)





5.8





5.7





5.5





5.2





4.7





4.0







∆ Lσ: sound insulation (level differential) (dB)





13.0





16.6





19.7





21.2





20.2





21.2







αa in dB/km





0.07





0.11





0.17





0.26





0.38





0.55











Table 1.4: Terrain correction for low-frequency noise of wind turbines located respectively. on land and at sea, all fully soundproofed (level differential), and atmospheric absorption coefficients per 1/3-octave at a relative humidity of 80% and an air temperature of 10 ° C

Terrain correction for offshore wind turbines are valid for the calculation of the low-frequency noise in a building near the coast. Noise must be calculated in a building, seen in the direction of the wind turbines is more than 200 m inland from the coast, is used instead of terrain correction for land placed wind turbines. For buildings that lie between 0 and 200 m from the shore, interpolated linearly between the two values for the terrain correction.

The total sound pressure level of the low frequency noise LpALF, tot in the dwelling is available then by summing the sound pressure levels LpALF, in in each 1/3-octave bands, see. equation Equation 1.4.2 1.4.2. Total sound pressure level

Ubestemtheden on the calculated sound pressure level LpALF, tot, using this approach are ± 2 dB.

Section 2

Special rules

2.1 determination of noise from wind farms

At a wind farm for the purposes of this Ordinance a collection of three or more identical wind turbines, regardless of whether these are placed on land or as offshore wind turbines.


The sound power level LWA, ref in 1/3-octave bands or 1/1 octave bands are determined by measurements at least three randomly selected wind turbines of the same type. For the other wind turbines used energy mean value of the three (or more) measured sound power levels.

The anemometer must, if it is placed in the side of one of the other tail-wind turbines have a distance to this wind turbine, which is at least ten times the wind turbine rotor diameter (d), see Figure 1.

The sound pressure level in 1/3-octave bands 1/1 octave band or at a point is found by summing individual noise contributions from wind turbines, calculated according to the equation 1.2.1, as indicated in equation 2.1 Equation 2.1. Total sound pressure level from more wind turbines

The same formula is used when the contribution from a new wind turbine should be added to the sound pressure level of existing wind turbines near the concerned housing produces.

The total A-weighted sound pressure level LpA, tot in point exists then by equation 1.2.2.

2.2 the measurement of noise removal from offshore wind turbines

A. the microphone mounted on a reflective plate on the ship

In relation to measurements of land-based wind turbines change the method of measurement, so that the reflective plate, as the microphone must be placed on, is placed on the roof of the wheelhouse on the measuring vessel or on any other similar large flat with free term from microphone placement to the turbine. Taken or surface must not in any context be less than 4 meters.

In addition, applies the instructions in Chapter 1, section 1.

B. the microphone mounted next to the ship

If the microphone cannot be placed as mentioned under point. (A), the microphone is placed 3-5 meters above sea level, free from reflective surfaces and the like and 1-2 meters out over the edge of the measuring ship with sight to the turbine. Microphone attached to a wind hood and microphone axis must point in the direction towards the wind turbine hubs.

The noise from the wind turbine is measured as A-weighted spectra in a number of periods according to the same guidelines as set out in section 1 of the country placed wind turbines, taking at the same time, the registration of the wind turbine produced the effect, the wind speed at hub height, measured with built-in anemometer, wind turbine and wind speed vz for a minimum of 10 m above sea level with the anemometer on the same vessel as the microphone. Due to low ruhedsværdi Marsh is vz = vref.

Is the background noise of strong can its impact be reduced by increasing the microphone height to 5 meters and reduce the measuring distance.

Turbine sound power level LWA, ref in 1/3-octave bands (or 1/1 octave bands) are hereinafter referred to as indicated in equation 2.2.



Equation 2.2. The sound power level of an offshore wind turbine

By measuring the noise pollution from wind farms at sea applies the instructions above on the measurement of noise from wind farms.

2.3 measurement of noise removal from small wind turbines

For small wind turbines, including household m, is determined the source strength after the principles of the method, as specified in 1.1 with option for the following deviation: • during the measurement microphone must be positioned so that the direction of the wind turbine tower for microphone ± 45 ° from the wind direction.

Small wind turbines usually have no opportunity for direct readout of the produced effect in short time intervals, and therefore determined the correlation between wind turbine noise and wind speed from measurements with an anemometer, which shall be drawn up in at least 10 m altitude near the turbine in a place where neither the turbine or objects in the terrain are estimated to affect wind measurements.