Resource Documents: Denmark (42 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: Johansson, Mauri
The history of wind turbines in Denmark started back in the 1970’s with very small but gradually bigger wind turbines which were mostly owned by local farmers. The big wind turbines (>1 MW) came in the late 2000’s but at a rather slow pace.
Documents based on the right of access in environmental and other Danish authorities have shown that already in the late 1980’s there were complaints about the noise, but local as well as central authorities generally refused to investigate, and did not involve medical expertise. This happens also today.
Despite these complaints for over 20 years, unfortunately no medically based research has ever been conducted in Denmark, even not as a base for “safe” distances and noise limitations. The only research has been engineer-performed noise measurements and calculations. This ignores the human physiological impact of the wind turbine noise, previously shown in research into the impacts of other noise sources. Engineers are not physicians, and therefore cannot assess the impact on human health. Furthermore, those acoustic engineers closely connected with the wind industry have an obvious yet rarely acknowledged financial conflict of interest.
Unfortunately, the formal Danish statutory orders relating to wind turbine noise pollution have been exported internationally, together with the turbines. This is even more problematic now, because of the increasing size of the wind turbines.
With the giant wind turbines (>1 MW) the relative amount of low-frequency noise, which is very intrusive and easily spreads far away, is increasing. This has been shown in independent research at Aalborg University by Acoustics Professor Henrik Moeller. Comments recently from Australian Emeritus Professor Colin Hansen have indicated that the same intrusive health and sleep damaging wind turbine noise is occurring in Australia at the Waterloo wind development (37 Danish Vestas V90 3-MW wind turbines), under certain meteorological conditions, at distances out to 10 km.
Unfortunately in Denmark there has been no systematic registration of complaints, or follow up for the people whose health and sleep have been affected by the noise. No information about risks for illness has ever been sent to GP’s or the hospital system. So in fact in Denmark we have no idea of the real numbers, and most farmers are uneasy to speak up about their health/illness problems. Speaking up also risks falling house and land prices or may even totally prohibit their sale.
There is no doubt, however, that the number of complaints of sleep and health problems from Danish residents is increasing. A few residents have had relevant medical examinations and among those who have, the causality of their symptoms from wind turbine noise has been confirmed on an individual, clinical level in a small number of cases.
Epidemiological research is totally lacking, and studies over longer time periods, too.
When the Danish statutory order for low-frequency noise was renewed during 2011, after considerable pressure from the public, a senior civil servant from the Environment Authority responsible for noise pollution regulation had a meeting with wind turbine industry officials in March 2011, where it was privately mutually agreed that the new order would NOT result in greater safety distances or higher requirements for protection from the low-frequency noise than the existing inadequate statutory order. This is exactly what subsequently happened, and resulted in strong protests from the Danish acousticians  and physicians  familiar with the reported health and sleep problems. The responsible authorities have continued to ignore those protests.
The CEO of Vestas, Ditlev Engel, in June 2011 sent a letter  to the then Minister of Environment to reinforce that no changes to the existing state of affairs could be acceptable, because of the risk to Danish exports and Danish jobs. The motivations of Vestas and others involved in the wind industry are therefore made very clear. Their stated corporate values do not match their actions.
The ongoing denials by Vestas of health and sleep problems including their latest global “Act on Facts” campaign launched recently in Australia  to be rolled out globally, are further evidence of their true intentions to maximize profits and grow their company and their business, at the direct expense of the health of citizens around the world.
There are no independent epidemiological studies that show that their product (wind turbines) is safe and does not cause the sleep deprivation and adverse health effects reported by the neighbours.
On the contrary, there are a growing number of peer-reviewed published studies that show there is considerable human distress, sleep deprivation and consequent impaired health and quality of life when wind turbines are installed as neighbours. A number of these studies were conducted in Sweden on smaller wind turbines almost 10 years ago  confirming that this problem is not new. Nor are the reported sleep and health problems caused by “scaremongering” or “the nocebo effect” in English speaking countries, as some public health advocates for the wind industry such as Professor Simon Chapman, a sociologist from Sydney University in Australia, are apparently alleging.
So please, do not continue to misinform the public outside of Denmark about the true situation for the increasing number of Danish citizens whose health and sleep is badly affected by low-frequency noise from wind turbines. The language barrier between English and Danish will not hide the truth.
These health and sleep problems are identical to those being reported around the world by wind turbine neighbours, and also by others affected by other sources of industrial low-frequency noise.
The ongoing denial of FACTS about the existence of serious sleep and health problems in wind turbine neighbours is unforgivable. So too is the refusal by authorities to properly measure the noise inside people’s homes, and the refusal to conduct the multidisciplinary medical research.
The comment made by retired Danish High Court judge Peter Roerdam in the Copenhagen Post on 16th November, 2012  that wind power is “an industry which has thoroughly corrupted the political system” is all too true, in my experience, and comes at the direct expense of the health of Danish people.
It is clear the institutional political corruption, and the lack of professional ethics on the part of wind industry acousticians and public health researchers, who ignore or deny the existence of the sleep and health problems and the consequent serious long-term damage to health, is not limited to Denmark.
Mauri Johansson, MD, MHH
Specialist in Community and Occupational Medicine
Denmark, 6th July 2013
11. https://www.wind-watch.org/documents/tag/nocebo/?titles=on, for critiques of the “nocebo” research from Australia and New Zealand, which purports to provide support the scaremongering hypothesis. Notably the peer-reviewed published research by Danish Acoustician Professor Moeller above (ref #2) on the effect of the increased size of the wind turbines on increased low-frequency noise is ignored by Professor Chapman.
Download original document: “Open Letter: Big wind turbines, health and disease – a Danish perspective”
Author: Teilmann, Jonas; and Carstensen, Jacob
Offshore wind farms constitute a new and fast growing industry all over the world. This study investigates the long term impact on harbour porpoises, Phocoena phocoena, for more than 10 years (2001–12) from the first large scale offshore wind farm in the world, Nysted Offshore Wind Farm, in the Danish western Baltic Sea (72 × 2.3 MW turbines). The wind farm was brought into full operation in December 2003. At six stations, acoustic porpoise detectors (T-PODs) were placed inside the wind farm area and at a reference area 10 km to the east, to monitor porpoise echolocation activity as a proxy of porpoise presence. A modified statistical BACI design was applied to detect changes in porpoise presence before, during and after construction of the wind farm. The results show that the echolocation activity has significantly declined inside Nysted Offshore Wind Farm since the baseline in 2001–2 and has not fully recovered yet. The echolocation activity inside the wind farm has been gradually increasing (from 11% to 29% of the baseline level) since the construction of the wind farm, possibly due to habituation of the porpoises to the wind farm or enrichment of the environment due to reduced fishing and to artificial reef effects.
Environmental Research Letters, 2012, Vol. 7, No. 4, 045101
Author: Renewable Energy Foundation
1. Onshore wind turbines represent a relatively mature technology, which ought to have achieved a satisfactory level of reliability in operation as plants age. Unfortunately, detailed analysis of the relationship between age and performance gives a rather different picture for both the United Kingdom and Denmark with a significant decline in the average load factor of onshore wind farms adjusted for wind availability as they get older. An even more dramatic decline is observed for offshore wind farms in Denmark, but this may be a reflection of the immaturity of the technology.
2. The study has used data on the monthly output of wind farms in the UK and Denmark reported under regulatory arrangements and schemes for subsidising renewable energy. Normalised age-performance curves have been estimated using standard statistical techniques which allow for differences between sites and over time in wind resources and other factors.
3. The normalised load factor for UK onshore wind farms declines from a peak of about 24% at age 1 to 15% at age 10 and 11% at age 15. The decline in the normalised load factor for Danish onshore wind farms is slower but still significant with a fall from a peak of 22% to 18% at age 15. On the other hand for offshore wind farms in Denmark the normalised load factor falls from 39% at age 0 to 15% at age 10. The reasons for the observed declines in normalised load factors can not be fully assessed using the data available but outages due to mechanical breakdowns appear to be a contributory factor.
4. Analysis of site-specific performance reveals that the average normalised load factor of new UK onshore wind farms at age 1 (the peak year of operation) declined significantly from 2000 to 2011. In addition, larger wind farms have systematically worse performance than smaller wind farms. Adjusted for age and wind availability the overall performance of wind farms in the UK has deteriorated markedly since the beginning of the century.
5. These findings have important implications for policy towards wind generation in the UK. First, they suggest that the subsidy regime is extremely generous if investment in new wind farms is profitable despite the decline in performance due to age and over time. Second, meeting the UK Government’s targets for wind generation will require a much higher level of wind capacity – and, thus, capital investment – than current projections imply. Third, the structure of contracts offered to wind generators under the proposed reform of the electricity market should be modified since few wind farms will operate for more than 12–15 years.
Download original document: “Analysis of Wind Farm Performance in UK and Denmark”
Denmark data files (zip)
UK data files (zip)
Author: Danish Society for Occupational and Environmental Medicine
DASAM [the Danish Society for Occupational and Environmental Medicine] has with interest read the proposal for a new executive order on noise from wind turbines. DASAM welcomes that low frequency noise from wind turbines are now being subjected to the same limits as low frequency noise from other industries during the night.
DASAM believes however, that the executive order not sufficiently protects against health risks due to noise and therefore recommends:
- The noise limits should be lowered from 39dB (A) to 35 dB (A).
- A health based assessment on the effects of introducing up to 1000 wind turbines in Denmark should be performed.
Based on current knowledge about the relationship between noise from wind turbines and effects on humans, and the raised critic on the quality of the proposed noise measurements, for example from researchers from Aalborg University, we are concerned whether the proposed noise limit values for wind turbines will sufficiently protect the Danish citizens against annoyance of living close to wind turbines.
A number of original papers and several reviews show that between 10% and 40% of citizens living close to wind turbines feel annoyed or extremely annoyed by the noise, and it is shown that the number of annoyed people rises sharply when the noise exceeds 35 dB [1-7]. Generally, it has not been possible to distinguish between nuisances from noise and low frequency noise respectively. Some of the studies also suggest that living near a wind turbine affect sleep quality and the most recent review concluded that “Wind turbine noise is causing noise annoyance and possible also sleep disturbance, which means that one cannot completely rule out effects on the cardiovascular system after prolonged exposure to wind turbine noise, despite moderate levels of exposure” .
Some case studies describe vibroacoustic disease and wind turbine syndrome in persons living close to wind turbines, but these findings have not been confirmed by more systematic studies.
The current noise limits that are unchanged in the new revised proposal is 44 dB(A) at 8 m/s (open land) and 39 dB(A) at 8 m/s (noise sensitive land use). Actually, the noise load can be considerably higher, due to 1) no enhanced noise limits in the night, even though it is well documented, that the noise reduction can be lowered 3-15 dB at night [8,9] and 2) that the noise level can increase at higher wind speeds.
As something new, an indoor noise limit value of 20 dB for low-frequency noise is proposed, but it is accepted, that the noise limit value will be exceeded in 33% of households living close to wind turbines. Basically DASAM finds this approach unacceptable. The Environmental Protection Agency’s calculation of the insulation capability of houses against low frequency noise – including the acceptance of the large number of exceedings – and the controversial use of measurement variability in the control measurements for noise has been strongly criticized by international experts in noise and acoustic . In the proposed executive order the noise insulation numbers are increased compared to earlier, resulting in calculated indoor levels of low frequency noise below 20 dB, despite the fact that the real levels are well above 20 dB. We refer to  and to the statement on the executive order from Aalborg University for further details.
We estimate that with the current noise limit values for wind turbines, an unacceptable proportion of citizens in the vicinity of wind turbines will be annoyed or strongly annoyed by the noise. In the suggested noise limit values it has not been taken into consideration that susceptible subjects due to e.g. pre-existing disease can be more sensitive to noise compared to the general population .
No studies so far have investigated the magnitude of the problem in Denmark, but based on studies from mainly Sweden and Holland DASAM recommends that the noise limit value is decreased from the current 39 dB (A) so in the future no more than 35 dB is allowed at residences at a wind speed of 8 m/s. It is also recommended to use 35 dB as the noise limit value in noise sensitive land use – today it is covered by the 44 dB noise limit value. By doing this the Danish noise limit values will become comparable to the Swedish  and the New Zeelandic  noise limit values. Based on present knowledge, this means that less than 10% of citizens living close to wind turbines will be annoyed by the noise.
DASAM finds it relevant that a health-based assessment is made of the effects of introducing as planned up to 1000 wind turbines in Denmark. DASAM can propose a person capable of performing the task, including suggestions on how effects of wind turbines may be monitored and estimated in the future.
Chairman, Danish Society for Occupational and Environmental Medicine
Associate Professor, MD, specialist in occupational medicine
Department of Public Health, Section for Environmental and Occupational Medicine
Aarhus University, Denmark
Tlf: +45 8617 8022 / +45 2899 2499
- Sammenhæng mellem vindmøllestøj og helbredseffekter. DELTA, marts 2011
- Infrasound and low frequency noise from wind turbines: exposure and health effects; Environ. Res. Lett. 6 (2011) 035103 (6pp)
- Health aspects associated with wind turbine noise – results from three field studies. Noise Control Eng J 59(1) 2011
- Perception and annoyance due to wind turbine noise—a dose–response relationship; J. Acoust. Soc. Am. 116 (6), December 2004
- Wind turbine noise, annoyance and self-reported health and well-being in different living environments; Occup Environ Med 2007;64:480–486
- Response to noise from modern wind farms in The Netherlands; J. Acoust. Soc. Am. 126 2, August 2009
- Evaluating the impact of wind turbine noise on health-related quality of life; Noise & Health, Sept-Oct 2011; 13:54,333-9)
- Effects of the wind profile at night on wind turbine sound; Journal of Sound and Vibration; doi:10.1016/j.jsv.2003.09.050
- Schneider, C.P. Accuracy of Model Predictions and the Effects of Atmospheric Stability on Wind Turbine Noise at the Maple Ridge Wind Power Facility, Lowville NY.2007
- Henrik Møller, Christian Sejer Pedersen, Steffen Pedersen, ”Miljøstyrelsens mystiske beregninger”, Kronik, Berlingske, 15. juni 2011
- New Zealand Standard. Acoustics – Wind farm noise DZ 6808. REPORT DRAFT