Wind Turbines : What s New?

Transcription

1 Wind Turbines : What s New? Ray Copes, MD, MSc Public Health Ontario Dalla Lana School of Public Health University of Toronto

2 Disclaimer No organizational position, personal professional assessment

3 Wind Power Potential Benefits Clean technology, non combustion, an answer to climate change and local/regional air pollution, helps meet emissions targets Renewable Economic benefits for communities and residents May present industrial development opportunity

4 Canadian Wind Energy Source:

5 Literature search Open literature last 10 years Databases Search terms Complex literature: biomedical, engineering, social science, policy, acoustics 5

6

7 Potential Health and Safety Risks? Appear modest compared with many other technologies: - Sound and vibration -Shadow flicker -Electromagnetic fields associated with generation and, transmission of electricity -Mechanical failure and ice throw Visual impacts 7

8 Photo: Edenfield, Lancashire, UK

9 Trend of Publications during the Past 10 Years 18 Number of Publications per Year

10 Noise 10

11 Night Noise Guidelines for Europe WHO 2009 Recent review of evidence on health effects Sufficient evidence for biological effects of noise during sleep: increase in heart rate, arousals, sleep stage changes, awakening Sufficient evidence that night noise causes self-reported sleep disturbance, increase in medication use, increase in body movements and insomnia Limited evidence that disturbed sleep causes fatigue, accidents and reduced performance Limited evidence that noise at night causes hormone level changes and clinical conditions such as cardiovascular illness, depression and other mental illness.

12 Thresholds Sufficient evidence EFFECT INDICATOR THRESHOLD (db) EEG awakening L A Max, Inside 35 Motility L A Max, Inside 32 Change in sleep structure L A Max, Inside 35 Wakening L A Max, Inside 42 Increased Ave Motility L night, outside 42 Self rep sleep dist L night, outside 42 Med use L night, outside 40 Env insomnia L night, outside 42

13 Thresholds Limited Evidence EFFECT INDICATOR Est. Threshold (db) Complaints L night, outside 35 Hypertension L night, outside 50 Myocardial Infarction L night, outside 50 Psychic disorders L night, outside 60

14 Summary Below 30 db L night, outside no effects on sleep are observed except for a slight increase in the frequency of body movements during sleep. There is no sufficient evidence that the biological effects observed at the level below 40 db L night, outside are harmful to health. However adverse effects are observed at the level above 40 db such as self-reported sleep disturbance, environmental insomnia and increased use of meds are observed. Therefore 40 db L night, outside is equivalent to the lowest observed adverse effect level for night noise.

15 Guidelines recommended Night noise guideline - L night, outside 40dB Interim Target - L night, outside 55dB

16 Wind farm sound target 40dB in many jurisdictions, although 45 and 35 also used by some. Environmental assessment of rail expansion 58-69dB with barriers homes m from tracks Source: CCOHS

17 Sound produced by wind turbines 17

18 A-weighted one-third-octave-band sound pressure levels at the distance from a single turbine, where the total A-weighted sound pressure level is 35 db Source: Low-frequency noise from large wind turbines, Henrick Moller and Christian Sejer Pederson Section of Acoustics, Adlborg University, Fredrick Bajers Vej 7-B5, DK-9220 Aalbord ), Denmark (2010)

19 Indoor A-weighted one-third-octave-band sound pressure levels at the distance from a single turbine, where the total A-weighted sound pressure level is 35 db; 81 turbine/room combinations. Dashed line is hearing threshold according to ISO (Ref 28) (colours indicate the turbine) Source: Low-frequency noise from large wind turbines, Henrick Moller and Christian Sejer Pederson Section of Acoustics, Adlborg University, Fredrick Bajers Vej 7-B5, DK-9220 Aalbord ), Denmark (2010)

20 Indoor A-weighted one-third-octave-band sound pressure levels at the distance from wind farms, where the total A-weighted outdoor sound pressure level is 44 db; 81 turbine/room combinations Dashed line is hearing threshold according to ISO (Ref 28) (colours indicate the turbine) Source: Low-frequency noise from large wind turbines, Henrick Moller and Christian Sejer Pederson Section of Acoustics, Adlborg University, Fredrick Bajers Vej 7-B5, DK-9220 Aalbord ), Denmark (2010)

21 Health Studies related to wind energy developments Questionnaire, self report only Cross-sectional Informative, but potential for bias Quality of exposure assessment varies: distance, visual impact, sound levels Questions include symptoms, self report of diagnosis, medication use, annoyance, sleep disturbance 21

22 Outcomes Consistent reports of annoyance, sleep disturbance Variety of symptoms, less consistency Relationship to sound levels, but important modifiers 22

23 Percentage of population highly disturbed by noise during sleep in the Netherlands: survey results for 1998 and 2003 Source: Night Noise Guidelines for Europe, WHO Europe (2009)

24 Factors that may influence annoyance from WT Sound level measured, modeled, distance as surrogate Benefit - Personal, Community Visual impact vertical visual angle, terrain (hilly v. flat) Use of property for restorative purposes Pre-existing sound levels Individual characteristics noise sensitivity, affect Central v. local decision making Views on wind energy Individual landowner v. community decision making 24

25 Response to wind turbine noise outdoors or indoors, proportion of respondents (n=708) according to -db(a) sound level intervals, and 95% confidence intervals (95%CI) Source: Night Response to noise from modern wind farms in the Netherlands, E. Pedersen, F. van den Berg, R. Bakker, J. Bouma (2009)

26 Comparison between respondents who benefited economically and those who did not Proportion of respondents in each sound emission interval who noticed sound from wind turbines outside their dwelling (left column) or were annoyed by it (right column) Source: Night Response to noise from modern wind farms in the Netherlands, E. Pedersen, F. van den Berg, R. Bakker, J. Bouma (2009)

27 Comparison between respondents who could see at least one wind turbine from their dwelling and those who could not Proportion of respondents in each sound emission interval who noticed sound from wind turbines outside their dwelling (left column) or were annoyed by it (right column) Source: Night Response to noise from modern wind farms in the Netherlands, E. Pedersen, F. van den Berg, R. Bakker, J. Bouma (2009)

28 Comparison between respondents living in built-up areas, rural areas with a main road, and rural areas without a main road Proportion of respondents in each sound emission interval who noticed sound from wind turbines outside their dwelling (left column) or were annoyed by it (right column) *=p<0.05, ** =p <0.01, *** = p< (Mann-Whitney U-test), a =built-up vs rural with main road, b =rural with main road vs rural without main road, and c =built-up vs rural without main road Source: Night Response to noise from modern wind farms in the Netherlands, E. Pedersen, F. van den Berg, R. Bakker, J. Bouma (2009)

29 Health Survey - Wind vigilance for Ontario communities Self reporting survey 98 report health affected, 26 did not (2011 update report symptoms) Recorded reports of headaches, palpitations, excessive tiredness, stress, anxiety, tinnitus, hearing problems, sleep disturbance, migraine, depression, other Allowed people to record their experiences, example follows

30 What do neighbours say? I can no longer sleep at all in the summer with my window open because the noise drives me nuts. I can also hear it sometimes when the windows are closed. The scenic landscape has been ruined both day and night. I have had people over and we would be sitting outside at night and they would tell me that those red lights would drive them crazy. It would be hard for me to say what is worse; the noise or the lights.

31 Visual Impacts Complicated Perhaps underappreciated as a factor contributing to annoyance, complaints and possibly other outcomes Terrain and other siting factors may help mitigate New computerized methods may help visualize better prior to construction 31

32 Are Wind Energy Developments Unique? Do they share feature with other local land use issues? What kinds of facilities generate complaints to public health? 32

33 12 Principal Outrage Components from Sandman, 1991 Safe Voluntary Natural Familiar Not memorable Not dreaded Chronic Knowable Individually controlled Fair Morally irrelevant Trustworthy sources Responsive process Risky Coerced Industrial Exotic Memorable Dreaded Catastrophic Unknowable Controlled by others Unfair Morally relevant Untrustworthy sources Unresponsive process

34 Can findings be used to reduce annoyance and conflict over wind turbine siting? Parallels with other development, land use controversies Locus of decision-making Distribution of benefits, negative impacts Attention to visual impacts terrain, 3D modeling Sound characteristics night noise, frequency? Pre-existing (background) sound levels Is controversy/conflict likely wane or increase over time? 34

35 Conclusions Community noise is an underappreciated public health issue Sound levels are one of the impacts of wind energy Visual impacts and other factors also play a role in acceptability at the local level Perils of Particularism Everyone wants the lights to stay on No zero impact way to generate power Need to consider noise and other impacts in context Don t forget equity 35

36 Acknowledgements Amira Aker Susanne Bell 36