Resource Documents — latest additions
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: Smith, Michael; Ögren, Mikael; Thorsson, Pontus; Hussain-Alkhateeb, Laith; Pedersen, Eja; Forssén, Jens; Ageborg Morsing, Julia; and Persson Waye, Kerstin
Onshore wind turbines are becoming increasingly widespread globally, with the associated net effect that a greater number of people will be exposed to wind turbine noise (WTN). Sleep disturbance by WTN has been suggested to be of particular importance with regards to a potential impact on human health. Within the Wind Turbine Noise Effects on Sleep (WiTNES) project, we have experimentally investigated the physiological effects of night time WTN on sleep using polysomnography and self-reporting protocols. Fifty participants spent three nights in the sound exposure laboratory. To examine whether habituation or sensitisation occurs among populations with long-term WTN exposure, approximately half of the participants lived within 1km of at least one turbine. The remaining participants were not exposed to WTN at home. The first night served for habituation and one WTN-free night served to measure baseline sleep. Wind turbine noise (LAEq,indoor,night=31.9 dB) was introduced in one night. This exposure night included variations in filtering, corresponding to a window being fully closed or slightly open, and variations in amplitude modulation
Michael Smith, Mikael Ögren, Laith Hussain-Alkhateeb, Julia Ageborg Morsing, Kerstin Persson Waye
Department of Occupational and Environmental Medicine, Institute of Medicine, University of Gothenburg, Sweden
Pontus Thorsson, Jens Forssén
Division of Applied Acoustics, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
Department of Architecture and the Built Environment, Lund University, Sweden
Presented at the 12th ICBEN Congress on Noise as a Public Health Problem, 18–22 June, Zurich
Sleep is vital for adequate health and wellbeing, yet by its very definition is reversible. Such reversibility presents the opportunity for external factors, including noise, to disrupt sleep as the brain awakes the body following environmental intrusion. The link between traffic noise and sleep disruption is well established, yet the effects of noise from wind turbines is comparatively under-examined, although the body of research is growing. There is some evidence for an association between sleep disturbance and wind turbine noise (WTN) levels, but there has also been recent work finding no link between one-year WTN averages and sleep outcomes.
Response to a sound is not wholly dependent on the acoustical characteristics such as level, duration and frequency content. An individual’s tolerance and attitude to a certain sound can moderate their response, and persistent exposure may lead to an increase or a decrease in reaction. In the case of habituation, repeated exposure over time results in an individual reacting less strongly than previously to an exposure of the same amplitude. For example, long-term behavioural adaptation to noise occurs in fish following repeated motorboat noise exposure following an initial increase in hiding. It is unclear however whether behavioural changes such as these in humans may reflect true habituation, involving synaptic plasticity mechanisms such as long-term depression, or if these changes are instead indicative of coping strategies. In the opposite direction to habituation, sensitisation occurs when repeated exposure leads to a stronger response over time. For instance, in the famous example of a dripping tap, the sound may be innocuous at first but can become unbearable after persistent exposure.
Possible habituation or sensitisation to WTN represents a potential explanation for the disparity in findings from research into the effects of WTN on human response. This paper therefore describes a study performed to investigate the physiological impact on sleep from WTN exposure. The Wind Turbine Noise Effects on Sleep (WiTNES) project was performed with the aims of investigating the physiological or psychological impact of WTN on sleep, and whether repeated WTN exposure at home may lead to habituation or sensitisation. …
The results of the models for each outcome, which includes WTN exposure night alone as a predictor, are presented in Table 4. All response items excepting tenseness, perceived sleep depth and social orientation were significantly negatively affected following nights with WTN exposure. Furthermore, the exposed study group differed from the control group in the majority of the response items, rating their sleep as worse even in the absence of WTN exposure. There was a significant effect of sex for sleep depth and WTN causing difficulty falling back asleep, in both instances with men having worse sleep. Effects of noise sensitivity were seen for WTN causing tiredness and both mood items. Regular sleep difficulties was a significant predictor for around half of all outcomes, including difficulty sleeping, one of the three outcomes for which no effect of WTN exposure was seen. No significant effects of age were found for any of the outcomes, and no WTN exposure × group interactions were observed.
Almost all measures of self-reported sleep were negatively impacted following nights with wind turbine noise. The WTN nights lead to increased sleep disturbance, reduced sleep quality, increased tiredness, increased irritation, awakenings, increased difficulty to sleep, sleeping worse than usual, and decreased mood. Subjects dwelling close to wind turbines, and consequently potentially exposed to WTN at home, repeatedly scored their sleep and restoration lower than the reference group following the WTN nights. However, their baseline sleep and restoration scored after the quiet WTN-free night were also generally scored lower than by the reference group. Although efforts were made during recruitment to obtain as similar a study sample from both the exposed and reference groups, a larger proportion of participants in the exposed group reported excessive tiredness at least once a month (58% vs. 20%) or difficulties sleeping at home at least several times a month (61% vs. 41%). Nevertheless, the effect of WTN exposure on sleep remained even after correcting for regular sleep difficulties and tiredness. … Despite the limitations of questionnaires and the study design, the present paper provides evidence that a single night of wind turbine noise at indoor levels of LAEq,8h=31.9 dB negatively impacts self-reported sleep.
Download original document: “Wind Turbine Noise Effects on Sleep: The WiTNES study”
The Indirect Impacts of Wind Farms on Terrestrial Mammals: Insights from the Disturbance and Exclusion Effects on Wolves (Canis lupus)
Author: Ferrão da Costa, Gonçalo; et al.
Due to the technical and functional characteristics of wind turbines, impact assessment studies have focused mainly on flying vertebrates. Nevertheless, evidence from the little available knowledge indicates potential impacts on large terrestrial mammals resulting from habitat fragmentation and increasing human disturbance. Over the last 15 years, more than 900 wind turbines were built inside the range of the Portuguese wolf. Due to the endangered status of this large carnivore in Portugal, several monitoring plans were conducted, resulting in a reasonable amount of information being collected on the effects of wind farms on wolves. We reviewed the methodological approaches, compiled major findings and summarised the mitigation/compensation measures used in Portuguese wind farms. The overall outcomes show increasing human disturbance in wind farm areas, resulting in lower wolf reproduction rates during construction and the first years of operation, as well as shifts in denning site locations of more than 2.5 km away from the wind farm. These findings are of major concern in humanised landscapes, where suitable wolf breeding habitats are reduced. As precautionary measure, new wind farm projects should be restricted in areas that are closer than 2 km from known wolf denning locations.
Gonçalo Ferrão da Costa
Bioinsight, Odivelas, Portugal
Grupo Lobo, Department of Animal Biology and CE3C—Centre for Ecology, Evolution and Environmental Changes, Faculty of Sciences, University of Lisbon, Portugal
CIBIO/InBIO—Research Center in Biodiversity and Genetic Resources, University of Porto, Vairão, Portugal
In: Mascarenhas M., Marques A., Ramalho R., Santos D., Bernardino J., Fonseca C. (eds) Biodiversity and Wind Farms in Portugal. Springer Cham, 2018; chapter 5, pp 111–134
Author: Hammerson, Geoffrey; et al.
Conservationists are increasingly concerned about North American bats due to the arrival and spread of the White-nose Syndrome (WNS) disease and mortality associated with wind turbine strikes. To place these novel threats in context for a group of mammals that provides important ecosystem services, we performed the first comprehensive conservation status assessment focusing exclusively on the 45 species occurring in North America north of Mexico. Although most North American bats have large range sizes and large populations, as of 2015, 18–31% of the species were at risk (categorized as having vulnerable, imperiled, or critically imperiled NatureServe conservation statuses) and therefore among the most imperiled terrestrial vertebrates on the continent [emphasis added]. Species richness is greatest in the Southwest, but at-risk species were more concentrated in the East, and northern faunas had the highest proportion of at-risk species. Most ecological traits considered, including those characterizing body size, roosting habits, migratory behavior, range size, home range size, population density, and tendency to hibernate, were not strongly associated with conservation status. However, nectarivorous bats tended to be more at risk. The conservation status of bats improved from 1985 to 2000 as human disturbances to roosting sites were reduced, but then declined sharply (7%) by 2015 due principally to threats from WNS and wind energy. Although uncertainty about threats from pollution and climate change remain, past experience shows that when threats are clearly identified and management actions taken, populations can recover.
G.A. Hammerson, NatureServe, Port Townsend, Washington
M. Kling, Dept. of Integrative Biology, University of California, Berkeley, California
M. Harkness, NatureServe, Boulder, Colorado
M. Ormes, NatureServe, c/o Biology Department, University of Massachusetts, Boston, Massachusetts
B.E. Young, NatureServe, Escazu, Costa Rica
Biological Conservation, Volume 212, Part A, August 2017, Pages 144-152
Download original document: “Strong geographic and temporal patterns in conservation status of North American bats”
A balanced solution to the cumulative threat of industrialized wind farm development on cinereous vultures (Aegypius monachus) in south-eastern Europe
Author: Vasilakis, Dimitris; Whitfield, D. Philip; and Kati, Vassiliki
Wind farm development can combat climate change but may also threaten bird populations’ persistence through collision with wind turbine blades if such development is improperly planned strategically and cumulatively. Such improper planning may often occur. Numerous wind farms are planned in a region hosting the only cinereous vulture population in south-eastern Europe. We combined range use modelling and a Collision Risk Model (CRM) to predict the cumulative collision mortality for cinereous vulture under all operating and proposed wind farms. Four different vulture avoidance rates were considered in the CRM. Cumulative collision mortality was expected to be eight to ten times greater in the future (proposed and operating wind farms) than currently (operating wind farms), equivalent to 44% of the current population (103 individuals) if all proposals are authorized (2744 MW). Even under the most optimistic scenario whereby authorized proposals will not collectively exceed the national target for wind harnessing in the study area (960 MW), cumulative collision mortality would still be high (17% of current population) and likely lead to population extinction. [emphasis added] Under any wind farm proposal scenario, over 92% of expected deaths would occur in the core area of the population, further implying inadequate spatial planning and implementation of relevant European legislation with scant regard for governmental obligations to protect key species. On the basis of a sensitivity map we derive a spatially explicit solution that could meet the national target of wind harnessing with a minimum conservation cost of less than 1% population loss providing that the population mortality (5.2%) caused by the operating wind farms in the core area would be totally mitigated. Under other scenarios, the vulture population would probably be at serious risk of extinction. Our ‘win-win’ approach is appropriate to other potential conflicts where wind farms may cumulatively threaten wildlife populations.
Dimitris P. Vasilakis
Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Aitoloakarnania, Greece; Directorate of Evros Region Forestry Service, Decentralized Administration of Macedonia-Thrace, Alexadroupolis, Evros, Greece
D. Philip Whitfield
Natural Research, Brathens Business Park, Banchory, Aberdeenshire, United Kingdom
Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Aitoloakarnania, Greece
PLoS One; Published February 23, 2017