Noise
Modern wind turbines produce significantly less noise than older designs. Turbine designers work to minimise noise, as noise reflects lost energy and output. Noise levels at nearby residences may be managed through the siting of turbines, the approvals process for wind farms, and operational management of the wind farm.
Renewable UK, a wind energy trade organization, has said that the noise measured 305 metres (1,000 ft) from a wind farm is less than that from normal road traffic or in an office;[90] some physicians and acoustic engineers have reported problems from wind turbine noise, including sleep deprivation, headaches, dizziness, anxiety, and vertigo.
In a 2009 report about “Rural Wind Farms”, a Standing Committee of the Parliament of New South Wales, Australia, recommended a minimum setback of two kilometres between wind turbines and neighbouring houses (which can be waived by the affected neighbour) as a precautionary approach.[111] In July 2010, Australia’s National Health and Medical Research Council reported that “there is no published scientific evidence to support adverse effects of wind turbines on health”.
A 2008 guest editorial in Environmental Health Perspectives published by the National Institute of Environmental Health Sciences, the U.S. National Institutes of Health, stated: “Even seemingly clean sources of energy can have implications on human health. Wind energy will undoubtedly create noise, which increases stress, which in turn increases the risk of cardiovascular disease and cancer.”
The Japanese Environment Ministry will begin a “major study into the influence of sounds of wind turbines on people’s health” in April 2010, because “people living near wind power facilities are increasingly complaining of health problems”. They plan a four-year examination of all 1,517 wind turbines in the country.
A 2007 report by the U.S. National Research Council noted that noise produced by wind turbines is generally not a major concern for humans beyond a half-mile or so. Low-frequency vibration and its effects on humans are not well understood and sensitivity to such vibration resulting from wind-turbine noise is highly variable among humans. There are opposing views on this subject, and more research needs to be done on the effects of low-frequency noise on humans.
Research by Stefan Oerlemans for the University of Twente and the Dutch National Aerospace Laboratory suggests that noise from existing wind turbines may be reducible by up to half by adding “saw teeth” to the trailing edges of the blades, although research is not complete. That said, the infrasound beside modern wind turbines is well below that experienced 75 meters from beaches, and surf has very similar characteristics to wind turbine noise; if there were a problem with infrasound and wind turbines, tens of millions of seaside dwellers would be experiencing significant health difficulties.[
2009 review
A 2009 expert panel review, described as being the most comprehensive to date, delved into the possible adverse health effects of those living close to wind turbines. Their report findings concluded that wind turbines do not directly make people ill.
The 85-page study was sponsored by the Canadian Wind Energy Association and American Wind Energy Association. The academic and medical experts who conducted the study stated that they reached their conclusions independent of their sponsors. "We were not told to find anything," said panel expert David Colby, a public health officer in Chatham-Kent and a Professor of Medicine at theUniversity of Western Ontario. "It was completely open ended."
The study did allow that some people could experience stress or irritation caused by the swishing sounds wind turbines produce. "A small minority of those exposed report annoyance and stress associated with noise perception..." [however] “Annoyance is not a disease.” The study group pointed out that similar irritations are produced by local and highway vehicles, as well as from industrial operations and aircraft.
The report found, amongst other things, that:
• “Wind Turbine Syndrome” symptoms are the same as those seen in the general population due to stresses of daily life. They include headaches, insomnia, anxiety, dizziness, etc…
• low frequency and very low-frequency “infrasound” produced by wind turbines are the same as those produced by vehicular trafficand home appliances, even by the beating of people’s hearts. Such ‘infrasounds’ are not special and convey no risk factors;
• Colby stated that evidence of harm was so minuscule that the wind associations were unable to initiate other independent collinear studies by government agencies. It was not surprising that their requests met with complete blanks on the need to examine the issues further;[6]
• one study member noted: “You can’t control the amount of cars going by and wind turbine noise is generally quieter than highway noise”
• the power of suggestion, as conveyed by news media coverage of perceived ‘wind-turbine sickness’, might have triggered “anticipatory fear” in those close to turbine installations.[6]
The study panel members included: Robert Dobie, a doctor and clinical professor at the University of Texas, Geoff Leventhall, a noise vibration and acoustics expert in the United Kingdom, Bo Sondergaard, with Danish Electronics Light and Acoustics, Michael Seilo, a professor of audiology at Western Washington University, and Robert McCunney, a biological engineering scientist at theMassachusetts Institute of Technology. McCunney contested statements that infrasounds from wind turbines could create vibrationscausing ill health: “It doesn’t really have much credence, at least based on the literature out there” he stated
2011 review
In 2011, the British Acoustics Bulletin published what is now the 10th independent review of the evidence on wind farms causing annoyance and ill health in people. And for the 10th time it has emphasised that “annoyance has far more to do with social and psychological factors in those complaining than any direct effect from sound or inaudible infrasound emanating from wind turbines”.
Two factors repeatedly came up. “The first is being able to see wind turbines, which increases annoyance particularly in those who dislike or fear them. The second factor is whether people derive income from hosting turbines, which miraculously appears to be a highly effective antidote to feelings of annoyance and symptoms”(Source: Wikipedia)
Dr.A.Jagadeesh Nellore(AP),India
Wind Energy Expert
E-mail: anumakonda.jagadeesh@gmail.com.

Despite generating clean, green and renewable energy, the residential wind turbines are considered to be noisy by many people. So the manufacturers must concentrate on developing less-noisy wind turbines to encourage more users to generate and use energy that is clean, green and renewable.