Resource Documents: Noise (563 items)
Documents presented here are not the product of nor are they necessarily endorsed by National Wind Watch. These resource documents are provided to assist anyone wishing to research the issue of industrial wind power and the impacts of its development. The information should be evaluated by each reader to come to their own conclusions about the many areas of debate.
Author: Schäffer, Beat; et al.
[Abstract] Current literature suggests that wind turbine noise is more annoying than transportation noise. To date, however, it is not known which acoustic characteristics of wind turbines alone, i.e., without effect modifiers such as visibility, are associated with annoyance. The objective of this study was therefore to investigate and compare the short-term noise annoyance reactions to wind turbines and road traffic in controlled laboratory listening tests. A set of acoustic scenarios was created which, combined with the factorial design of the listening tests, allowed separating the individual associations of three acoustic characteristics with annoyance, namely, source type (wind turbine, road traffic), A-weighted sound pressure level, and amplitude modulation (without, periodic, random). Sixty participants rated their annoyance to the sounds. At the same A-weighted sound pressure level, wind turbine noise was found to be associated with higher annoyance than road traffic noise, particularly with amplitude modulation. The increased annoyance to amplitude modulation of wind turbines is not related to its periodicity, but seems to depend on the modulation frequency range. The study discloses a direct link of different acoustic characteristics to annoyance, yet the generalizability to long-term exposure in the field still needs to be verified.
Journal of the Acoustical Society of America 2016 May;139(5):2949.
Beat Schäffer, Reto Pieren, Kurt Heutschi
Laboratory for Acoustics/Noise Control, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
Sabine J. Schlittmeier, Ralf Graf, and Jürgen Hellbrück
Work, Environmental, and Health Psychology, Catholic University of Eichstätt-Ingolstadt, Eichstätt, Germany
Noise and NIR Division, Federal Office for the Environment, Bern, Switzerland
Author: Lee, Seunghoon; Kim, Kyutae; Choi, Wooyoung; and Lee, Soogab
A listening test has been performed to investigate the relationship between human annoyance and the amplitude modulation of wind turbine noise. To obtain sound samples for the listening test, sound from a 1.5 MW wind turbine in Korea was recorded. The strength of the amplitude modulation of the sound samples was defined in terms of the modulation depth spectrum, which was approximated by assuming that the sound samples are sinusoidally amplitude-modulated. The stimuli for the listening tests were created by reducing the modulation depth spectrum of the sound samples. A total of 30 participants were involved in the listening tests. The results of the listening tests indicate that the equivalent sound level and the amplitude modulation of wind turbine noise both significantly contribute to noise annoyance.
Noise Control Engineering Journal 59 (1), Jan-Feb 2011
Seunghoon Lee, Kyutae Kim
School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Republic of Korea
Romax Technology Korea, Seochogu, Seoul, Republic of Korea
Institute of Advanced Aerospace Technology, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Republic of Korea
Author: Agnew, Roseanna; Smith, Valerie; and Fowkes, Robert
ABSTRACT: A paucity of data exists with which to assess the effects of wind turbines noise on terrestrial wildlife, despite growing concern about the impact of infrasound from wind farms on human health and well-being. In 2013, we assessed whether the presence of turbines in Great Britain impacted the stress levels of badgers (Meles meles) in nearby setts. Hair cortisol levels were used to determine if the badgers were physiologically stressed. Hair of badgers living >1 km of a wind farm had a 264% higher cortisol level than badgers <10 km from a wind farm. This demonstrates that affected badgers suffer from enhanced hypothalamo-pituitary-adrenal activity and are physiologically stressed. No differences were found between the cortisol levels of badgers living near wind farms operational since 2009 and 2012, indicating that the animals do not become habituated to turbine disturbance. Cortisol levels in the affected badgers did not vary in relation to the distance from turbines within 1 km, wind farm annual power output, or number of turbines. We suggest that the higher cortisol levels in affected badgers is caused by the turbines’ sound and that these high levels may affect badgers’ immune systems, which could result in increased risk of infection and disease in the badger population.
Roseanna C. N. Agnew, Valerie J. Smith, and Robert C. Fowkes
Royal Veterinary College, Royal College Street, London, UK
Zoological Society of London, Regent’s Park, London, UK
Scottish Oceans Institute, University of St. Andrews, St Andrews, Fife, UK
Journal of Wildlife Diseases, 52(3), 2016
Author: National Institute of Hygiene, National Institute of Public Health, Poland
The National Institute of Public Health–National Institute of Hygiene is of the opinion that wind farms situated too close to buildings intended for permanent human occupation may have a negative impact on the comfort of living and health of the people living in their proximity.
The human health risk factors that the Institute has taken into consideration in its position are as follows:
- the emitted noise level and its dependence on the technical specifications of turbines, wind speed as well as the landform and land use around the wind farm,
- aerodynamic noise level including infrasound emissions and low-frequency noise components,
- the nature of the noise emitted, taking into account its modulation/impulsive/tonal characteristics and the possibility of interference of waves emitted from multiple turbines,
- the risk of ice being flung from rotors,
- the risk of turbine failure with a rotor blade or its part falling,
- the shadow flicker effect,
- the electromagnetic radiation level (in the immediate vicinity of turbines),
- the probability of sleep disruptions and noise propagation at night,
- the level of nuisance and probability of stress and depression symptoms occurring (in consequence of long exposure), related both to noise emissions and to non-acceptance of the noise source.
In the Institute’s opinion, the laws and regulations currently in force in Poland (regarding risk factors which, in practice, include only the noise level) are not only inadequate to facilities such as wind turbines, but they also fail to guarantee a sufficient degree of public health protection. The methodology currently used for environmental impact assessment of wind farms (including human health) is not applicable to wind speeds exceeding 5 m/s. In addition, it does not take into account the full frequency range (in particular, low frequency) and the nuisance level.
In the Institute’s view , owing to the current lack of a comprehensive regulatory framework governing the assessment of health risks related to the operation of wind farms in Poland, an urgent need arises to develop and implement a comprehensive methodology according to which the sufficient distance of wind turbines from human habitation would be determined. The methodology should take into account all the above-mentioned potential risk factors, and its result should reflect the least favourable situation. In addition to landform and land use characteristics, the methodology should also take into consideration the category, type, height and number of turbines at a specific farm, and the location of other wind farms in the vicinity. Similar legislative arrangements aimed to provide for multi-criteria assessment, based on complex numerical algorithms, are currently used in the world.
The Institute is aware of the fact that owing to the diversity of factors and the complicated nature of such an algorithm, its development within a short time period may prove very difficult. Therefore, what seems to be an effective and simpler solution is the prescription of a minimum distance of wind turbines from buildings intended for permanent human occupation. Distance criteria are also a common standard-setting arrangement. Having regard to the above, until a comprehensive methodology is developed for the assessment of the impact of industrial wind farms on human health, the Institute recommends 2 km as the minimum distance of wind farms from buildings. The recommended value results from a critical assessment of research results published in reviewed scientific periodicals with regard to all potential risk factors for average distance usually specified within the fo0llowing limits:
- 5-0.7 km, often obtained as a result of calculations, where the noise level (dBA) meets the currently acceptable values (without taking into account adjustments for the impulse/tonal/modulation features of the nose emitted),
- 5-3.0 km, resulting from the noise level, taking into account modulation, low frequencies and infrasound levels,
- 5-1.4 km, related to the risk of turbine failure with a broken rotor blade or its part falling (depending on the size of the piece and its flight profile, rotor speed and turbine type),
- 5-0.8 km, where there is a risk of ice being flung from rotors (depending on the shape and mass of ice, rotor speed and turbine type),
- 0-1.6 km, taking into account the noise nuisance level (between 4% and 35% of the population at 30-45 dBA) for people living in the vicinity of wind farms,
- the distance of 1.4-2.5 km, related to the probability of sleep disruptions (on average, between 4% and 5% of the population at 30-45 dBA),
- 2.0 km, related to the occurrence of potential psychological effects resulting from substantial landscape changes (based on the case where the wind turbine is a dominant landscape feature and the rotor movement is clearly visible and noticeable to people from any location),
- 2-2.1 km, for the shadow flicker effect (for the average wind turbine height in Poland, including the rotor, of 120 to 210 m).
In its opinions, the Institute has also taken into account the recommended distances of wind farms from buildings, as specified by experts, scientists, as well as central and local government bodies around the world (usually 1.0-5.0 km).