The sounds of the night wind turbines reduce REM sleep, this being the only fixed devices sleep disturbance due to wind turbines. This effect is short term and does not depend on the length of stay in terms of noise. However, subjective feelings the morning after waking up under the turbines was negative at the majority of study participants. Article published in Oxford University Press.
Wind power generators is a key element of alternative energy, the transition to which is planned in most of the developed world. But, since they have begun to establish from nearby residents began to receive noise complaints. So, before you make a decision on further expansion of wind turbines, it is necessary to assess the seriousness of the negative impact of their sounds on people and nature.
Michael Smith (Michael Smith) from the University of Gothenburg and his colleagues decided in the laboratory to study the influence of the sound wind blades on human sleep. To do this, they selected a group of 50 volunteers, of whom 24 were living near the turbines, and 26 without them. Participants aged 36 to 70 years had serious health problems, was not working the night shift, did not practice meditation and similar practices.
All subjects spent three nights in the Soundproofed room, where the ceiling was a speaker installed, through which one night was lost to the sounds of wind turbines, including voice through the closed window. Generators can rotate at a different frequency, and for the experiment was chosen as the one which is associated with the most complaints: thirteen revolutions per minute. People were assigned a standard set of equipment used for the scientific study of dreams: withdrawals of electroencephalogram, electrocardiogram, oculogram, was measured the electrical resistance, and also took a saliva test for cortisol — a hormone associated with stress.
As a result, contrary to assumptions, it was found that long-term residence near wind turbines does not have any long-term effect on sleep and the night people from two different groups did not differ among themselves nor with the included sounds or off. The devices also did not record any significant differences between sleep under the noise of the turbines and without it, except for one thing: with sounds by subjects from the period REM sleep was reduced on average by eleven minutes. Despite the fact that REM sleep is critical to health, we cannot say that it reduce for a few minutes causes immediate harm to the body. The authors note that such is the impact of other sources of similar noise, e.g., trains or cars.
Meanwhile, people’s opinions differed from the readings. Many study participants from both groups after a night under the noise of wind turbines argued that worse sleep, not feeling rested, and that it was hard to sleep back after a night waking. It doesn’t provide direct physiological harm from wind turbines, but chronic subjective dissatisfaction with sleep who also refers to potentially hazardous factors. The authors conclude that further research is necessary to conduct with a large number of people for a long time.
In connection with the growth of living standards, scientists began to pay close attention to the dream. For example, they found that he promotes optimism and a hot tub, and overall healthy sleep protects from cardiovascular disease.