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.
Inter-Noise 2014: 43rd International Congress on Noise Control Engineering
Melbourne, Australia, 16-19 November 2014
The noise characteristics of ‘compliant’ wind farms that adversely affect its neighbours
Sarah Large, Mike Stigwood
MAS Environmental, UK
In the UK many wind farms cause complaints of noise despite complying with control limits. Problems relate to reliance on the LA90 index, failure to consider or apply ratings on the context of the sound characteristics and actual human responses due to complex characteristics. In general in the UK low frequency and very low frequency sound effects are either ignored or denied. The complex interrelationship of features within this noise and difficulties in quantifying and qualifying noise impact and inappropriate comparison with other sources of noise renders the effects difficult to investigate or quantify with contradictory outcomes possible using the same data sets. Claim and counterclaim of health and adverse effects complicate the analysis. This paper explores some of the interrelating characteristics of wind farm noise measured and observed in the field that appear to influence complaints made by communities. Cumulative effects occurring in environments normally dominated by natural sounds and both audible and inaudible elements remain alien sounds which are not habituated to. It appears that sensitisation arises. The physical reason for the failure to appropriately identify modulating noise effects and in particular low frequency modulating noise problems are explored.
Initial findings of the UK Cotton Farm Wind Farm long term community noise monitoring project
Mike Stigwood, Duncan Stigwood, Sarah Large
MAS Environmental, UK
This paper provides early results of a long term study of community impact from wind farm noise and uses of the data obtained. A continuously recorded database of noise collected under different meteorological conditions has allowed detailed analysis of particular characteristics such as amplitude modulation and also the reliability of assessment methodologies for predicting and quantifying impact. Surprising outcomes are explored including upwind impact. In 2013 MAS Environmental established a permanent monitoring station to record and publish data online located 600m from the nearest turbine to correlate the impact upon the community and provide an extensive database. This paper maps the evolution of the project. Online data enables a wider study of the effect of meteorological change on noise immission in a flat eastern area of the UK. Anyone can independently observe and listen to the audible elements of the noise that people complain about. This tool aids understanding as well as predicting times of likely adverse impact. The database has enabled testing of proposed controls, particularly in relation to audible amplitude modulation and demonstrated the recent Renewables UK proposed control mechanism fails. Data obtained challenges blade stall research claims as the primary cause of far field AM and wind farm noise prediction methodologies.
Investigating the impacts of wind turbine noise on quality of life in the Australian context: A case study approach
David Mcbride, Daniel Shepherd, Robert Thorne
University of Otago, New Zealand; Auckland University of Technology, New Zealand; Noise Measurement Services, Australia
The WHO considers noise pollution to be of sufficient threat to public health to justify the publication of guidelines on noise effects and mitigation. ‘Community noise’ has largely been studied in the context of transportation and general neighbourhood noise, with exposure to wind turbine noise relatively understudied for historical, methodological, and political reasons. There also appears to be a general uncoupling of wind turbine noise from the other sources, which endows upon it an exclusivity that excuses it from the methods, guidelines, and critique used for other noise sources. This study aimed to advance understanding of wind turbine noise impacts by adopting a case study approach based on detailed information from 25 individuals, Australian adults residing rurally and within 1000-3500m of three or more wind turbines. Participants were selected on the basis of health concerns evidenced through statutory declarations or submissions to hearings. The 25 respondents compeleted a face-to-face survey measuring health-related quality of life (HRQOL) questionnaire as developed by the World Health Organisation (WHO), the ‘WHOQOL-BREF’. The results were compared to normative population data and showed clinically significant reduction in HRQOL.
Outcome of systematic research on wind turbine noise in Japan
Professor Emeritus, The University of Tokyo
In Japan, serious complaints about wind turbine noise have arisen from nearby residents since the commencement of large-scale construction of wind generation plants in about 2000. Regarding this new type of environmental noise problem, scientific knowledge is insufficient and no standard methods for measuring and assessing the noise have been established in Japan. To improve this situation, a research project entitled “Research on the evaluation of human impact of low frequency noise from wind turbine generators” has been conducted over the three years from fiscal year 2010, funded by a grant from the Ministry of the Environment, Japan. This project consisted of three main subjects: (1) physical research on wind turbine noise by field measurement, (2) a social survey on the response of nearby residents, and (3) auditory experiments on the human response to noises containing low frequency components. In this paper, the outcome of the research project is reviewed and standard methods for measuring and assessing the wind turbine noise are discussed.
Special noise character in noise from wind farms
Valeri V. Lenchine, Jonathan Song
SA Environment Protection Authority, Australia
Noise produced by wind farms may exhibit a multitude of different noise characters, ranging from amplitude modulation, tonality and low frequency noise. The presence of the noise characters is able to increase the annoyance factor caused by a noise source significantly. A penalty to the noise levels is applied in accordance with some regulations when a noise character is detected. This paper discusses a noise character that can be described as “rumbling” that was detected during a long term monitoring program which was conducted in an area adjacent to a wind farm. The objective assessment of the data and subjective assessment of relevant audio records were performed to analyze the effect. The frequency spectra of the rumbling events indicate connection of the effect with low frequency noise and one of the low frequency components. The character was detected at low noise levels and might not be audible to a typical listener, however it is possible the character may cause an increased annoyance to people who have a higher sensitivity to the lower frequencies. Environmental conditions were also considered when discussing the occurrence of this noise character. The possible mechanism of the rumbling effect is suggested in the paper. The wind farm manufacturers may have to consider potential for low frequency impact of wind turbines and presence of prominent components at the design stage.
Correlation of amplitude modulation to inflow characteristics
Helge Aa. Madsen, Franck Bertagnolio, Andreas Fischer, Christian Bak
DTU Wind Energy, Technical University of Denmark
Amplitude modulation (AM) of noise from wind turbines and its more extreme version named “other amplitude modulation” OAM have been investigated intensively during the last few years due to the additional annoyance impact this type of noise has compared to broad band noise. In a recent published research by RenewableUK the hypothesis has been that one of the causes of OAM is transient stall on the blade due to non uniform inflow such as shear. Part of the RenewableUK research work was a contribution by DTU on analysis of data from the DANAERO MW experiment from 2009. In the DANAERO experiment a new 38.8m test blade for a 2MW NM80 turbine was manufactured and equipped with a massive instrumentation comprising flush mounted surface microphones, pressure taps and five hole pitot tubes. The correlation of the spectra from the surface microphones and the measured inflow angle (IA) confirmed the strong increase in the noise source for high IA. As only few 10min data sets were measured in the DANAERO project a data set with measured inflow angle from 2003 on the same turbine has been used to explore the statistical properties of AM and OAM based on assumed correlation to IA.
Wind turbine noise measurements – How are results influenced by different methods of deriving wind speed?
Hayes McKenzie Partnership Ltd, United Kingdom
With the increasing number of operational wind farms/turbines, the requirement for noise measurements required to demonstrate compliance with planning conditions is increasing as well. The British ETSU-R-97 noise limits are often set relative to measured or standardised 10 m height wind speeds and therefore the assessment of noise from wind turbines requires simultaneous noise and wind speed/direction measurements. For financial reasons, smaller and single turbine sites are often not equipped with a meteorological mast. If no independent hub height wind measurements are available, wind speed is either taken from nacelle anemometers or derived from power measurements combined with the power curve for the respective wind turbine type. Noise measurements referenced to nacelle anemometer data will be compared with the same measurements but correlated with derived power curve wind speed, and measured wind data from separate met mast or other remote sensing devices. The influence of incorrect filtering of wind data for shadow effects (mast and/or nearby wind turbines) on the noise assessment may be presented, depending on how much time is available. The advantages and disadvantages of the various methods will be discussed.
Using wind farm noise auralisations for effective community consultation
Frank Butera, Kym Burgemeister, Kai Fisher, David Mounter
Arup, Melbourne, Australia, and Singapore; Hydro Tasmania, Hobart, Australia
Two of the most common questions that wind farm developers face during community consultation are ‘what will the wind farm look like’ and ‘what noise will it make?’ A lot of work has been undertaken recently to develop ‘visualisations’ or ‘photomontages’ to answer the first question. However, there has not been an equivalent tool available to enable local communities to understand what a wind farm actually sounds like. Arup and Hydro Tasmania have jointly developed a tool that will accurately and effectively communicate what a wind farm sounds like under different wind conditions and from a range of distances and orientations. This auralisation tool provides a practical and affordable means for the industry to effectively communicate what a wind farm will sound like to the community. This paper looks at how auralisation techniques used in other sectors (such as transport and aviation) have been adapted for the renewable wind energy sector and serve as a valuable tool for increasing transparency, minimising risk and building trust within local communities early in the wind farm development process. It shows how a comprehensive field measurement program at Studland Bay Wind Farm, Tasmania has enabled a wind turbine sound library to be developed for future use in wind farm acoustic models and how calibrated auralisations can be presented at community settings.
The relevance of the precautionary principle to wind farm noise planning
Noise Measurement Services Pty Ltd, Australia
Wind farms consist of clusters of industrial wind turbines which, when placed in rural areas, are associated with intrusive and unwanted sound. Wind turbine noise has characteristics sufficiently different from other, more extensively studied, noise sources to suggest that standard industrial noise standards are not appropriate for measurement and assessment purposes. A seven year study is reported and, although limited in population size, it is clear that there are definite adverse health effects related to wind farm noise. Time-aggregated noise metrics have limited utility in assessing individual human health and well-being, and a cluster of metrics are needed to describe and estimate potential effects on individuals and communities. Sleep deprivation is a widely reported occurrence by people in the vicinity of a wind farm. At this time, however, the quantity and quality of research are insufficient to effectively describe the relationship between wind turbine noise and health, and until such time that a definitive relationship is obtained, legislation should apply the precautionary principle and conservative criteria when assessing proposed wind farm developments.
Wind turbine sound – metric and guidelines
Conny Larsson, Olof Öhlund
Uppsala University, Sweden
The meteorological conditions vary over the globe but also change over the day and the year and vary a lot depending on the terrain for a certain location. The meteorological parameters govern both the wind turbine emission sound levels and the sound propagation conditions and therefore gives rise to different sound immission levels. Long-time measurements of meteorological effects on sound propagation from wind turbines over forest areas have been performed at two sites in Sweden for more than two years. One site is located in the southern part with flat terrain and the other site is located in the northern part of Sweden with more hilly terrain. The aim of the project is to improve the knowledge of sound propagation from wind turbines and especially over varying terrain and weather conditions. Control measurements of wind turbine immission sound levels will be needed to see that they fulfill the noise regulations. It is therefore of most importance to be able to make representative measurements. Discussions about under what meteorological conditions the immission measurements have to be carried out, the sound metric and the impact of the guidelines are presented in this paper.
An investigation of different secondary noise wind screen designs for wind turbine noise applications
Colin Novak, Anders Sjöström, Helen Ule, Delphine Bard, Göran Sandberg
University of Windsor, Canada; Lund University, Sweden; Akoustik Engineering Limited, Canada
The use of diaphragm type microphones with the typical foam windscreen ball for outdoor noise measurement applications are mostly restricted to wind speeds below 4 to 6 m/s. This is due to the extra noise induced into the microphone, particularly at low and infrasonic frequencies, as a result of the wind excitation on the diaphragm. For wind turbine noise measurement applications, it is often necessary to measure the turbine noise under the typical operating conditions with wind speeds up to 12 m/s. This introduces a problem in the measurement system, as the normal microphone setup and windscreen are not adequate at these elevated wind speeds. Secondary windscreens, such as for example that prescribed by IEC 64100-11, “Acoustic noise measurement techniques” imparts their own problems including ridged body motion of the windscreen structure due to turbulence. Also, ground plane secondary windscreen measures the noise at ground level, instead of at ear level. This study investigates the use of several secondary windscreens with microphones capable of measuring at infrasonic frequencies for measuring wind turbine noise at elevated wind speeds. The result was that no windscreen provided a full solution to the problem. Specific recommendations for additional windscreen design and investigation are included.
Noise and low frequency noise from wind turbines
Grontmij, Department of Acoustics, Acoustica, Denmark
Noise is a key issue when planning wind farms. The presentation will look into details in noise from wind turbines, noise measurements, noise assessment, including the Danish noise limits for low frequency wind turbine noise, and noise propagation. Development of noise and low frequency noise with the size of the turbines will be discussed. Questions like how far does low frequency noise propagate will be addressed.
Author: Dai, Kaoshan; Bergot, Anthony; Liang, Chao; Xoang, Wei-Ning; and Huang, Zhenhua
Recognized as one of the most mature renewable energy technologies, wind energy has been developing rapidly in recent years. Many countries have shown interest in utilizing wind power, but they are concerned about the environmental impacts of the wind farms. The continuous growth of the wind energy industry in many parts of the world, especially in some developing countries and ecologically vulnerable regions, necessitates a comprehensive understanding of wind farm induced environmental impacts. The environmental issues caused by wind farms were reviewed in this paper by summarizing existing studies. Available mitigation measures to minimize these adverse environmental impacts were discussed in this document. The intention of this paper is to provide state-of-the-art knowledge about environmental issues associated with wind energy development as well as strategies to mitigate environmental impacts to wind energy planners and developers.
Renewable Energy 75 (2015) 911–921
Wind energy induced environmental issues:
Effects on birds
Effects on bats
Effects on marine species
Deforestation and soil erosion
Reception of radio waves and weather radar
Mitigation of wind energy environmental risks:
Limiting the effects on birds and bats
Reducing influence on marine environment and climate
Mitigating visual impact
Reducing electromagnetic interference
Author: Vermonters for a Clean Environment
1. Wind is a mature industry – it’s time for it to stand on its own. The Joint Committee on Taxation reports that between 1992 and 2015 , the cumulative cost of the PTC, without extension, will be approximately $17 billion with the bulk of this claimed by wind resources constructed since 2006. These costs are in addition to the anticipated $22.6 billion in direct cash outlays under the Section 1603 grant program now expired. Yet, after decades of government support of multiple kinds, the wind industry remains economically unviable.
2. The wind-sector slow-down is not tied to the end of the PTC. The wind industry insists it’s at risk of a slow-down without the PTC and jobs will be lost. But this view ignores crucial factors driving development in the United States. Demand for wind has eroded, in part, due to states meeting their renewable mandates. Lower natural gas prices have further reduced wind’s attractiveness as a ‘fuel saver’. Faced with these market conditions, wind developers are tabling projects. The Energy Information Administration  now forecasts flat growth in the wind sector for this decade regardless of what happens with the PTC.
3. Wind energy is costly, and government efforts to offset the cost distort the markets. Wholesale power contract prices for onshore wind are roughly two- to three- times the price of more reliable generation, making wind one of the most expensive power sources in the U.S. even after the PTC is factored in. The PTC offsets the high price of wind energy, giving the false impression that wind is competitive with other resources, but at 2.3¢/kWh, the subsidy’s pre-tax value (3.5¢/kWh) equals, or exceeds the wholesale price of power in much of the country. The size of the subsidy relative to wholesale prices is distorting competitive wholesale energy markets and harming the financial integrity of other, more reliable generation .
4. The industry’s job-creation claim is based on one-sided, simplistic modeling. The wind industry insists the PTC enables American jobs but ignores potential jobs that would be created given alternative spending of federal funds. Further, industry job forecasts fail to report on the more important net job creation. In states like Vermont, government models have shown that above- market energy costs tied to renewables reduce any positive employment impacts of renewable energy capital investment . This is without taking into account additional costs associated with wind-related transmission build-out and grid integration costs associated with wind energy’s intermittency.
 M. Sherlock Testimony, April 2012. http://science.house.gov/sites/republicans.science.house.gov/files/documents/hearings/HHRG-112-SY21-WState-MSherlock-20120419.pdf
 Energy Information Administration. EIA Reference case for wind energy, June 2012. http://www.eia.gov/oiaf/aeo/tablebrowser/#release=AEO2012&subject=0-AEO2012&table=16-AEO2012®ion=0-0&cases=ref2012-d020112c
 Northbridge Group, Negative Electricity Prices and the Production Tax Credit. September 2012. http://www.nbgroup.com/publications/Negative_Electricity_Prices_and_the_Production_Tax_Credit.pdf
 Vermont Department of Public Service, The Economic Impacts of Vermont Feed in Tariffs. December 2009. http://publicservice.vermont.gov/planning/DPS%20White%20Paper%20Feed%20in%20Tariff.pdf
Author: Residents of Ohio
Sorry, this post has been removed, to be published later.
The undersigned residents of Ohio communities affected or threatened with industrial wind development wish to bring to your attention the untenable situation we face due to the failure of the Ohio Power Siting Board (“OPSB”) to protect the public interest. We assert that the OPSB has not adopted rules that adequately and faithfully implement the requirements of siting statutes. Moreover, it has acted in ways that contribute to public confusion resulting in the loss of due process. The actions and omissions of the OPSB have abridged our fundamental constitutional right to be protected and secure in the possession of our property. We call for legal reforms to curb the errors and failures in the Board’s administration of the wind power siting program over the past six years.
For example, the OPSB was supposed to complete a mandatory five-year review of its rules through a proceeding it initiated in July 2012; to this end it issued orders adopting new rules in Case No. 12-1981-GE-BRO. Throughout that rulemaking proceeding, OPSB invited the input of utilities, wind developers, parties who recently filed applications, and their attorneys. However, the Board never notified or solicited the input of members of the public who intervened in OPSB matters. The Board did not even notify intervenors who were extensively involved in the development of the Board’s original wind power siting rules in 2008-09. Furthermore, the Board never filed notice of the proposed or final rules in the Register of Ohio, presumably because the OPSB and PUCO are exempt from the notice-and-comment rulemaking requirements of R.C. Chapter 119. In sum, while the Board’s recent rulemaking was open to utilities, wind developers, other regulated entities, and their attorneys, the process was entirely “under the radar” as far as the public was concerned.
Furthermore, under Ohio law, agencies such as the OPSB must file newly adopted rules with the Joint Committee on Agency Rule Review (“JCARR”) so that the rules can be evaluated by the General Assembly based on specified legal criteria. Yet, although the OPSB adopted its new set of rules on February 18, 2014, the OPSB has not filed its newly adopted wind power siting rules with JCARR and is thereby denying the public an opportunity to address the mismatch between the OPSB’s rules and the requirements specified by the Ohio General Assembly.
Time and again OPSB’s hearing process has proven hostile to public participation. Before approving a power siting certificate, the Board must hold both a “public hearing” at which any interested party may be heard and an “evidentiary hearing” at which only the applicant, Board Staff, and approved intervenors may participate. But the Board representatives conducting public hearings refuse to answer questions about the project and refer members of the public back to the wind developer for responses to their questions. In evidentiary hearings, the Board routinely imposes a discriminatory double standard by requiring intervenors (usually members of the public) to submit live expert witness testimony while allowing developers to submit reams of documentary information as “evidence” without expert support. The Board delegates the oversight and conduct of both hearings to an Administrative Law Judge employed by the PUCO, who then prepares the written decision and certificate for the Board’s approval (usually at a single meeting with minimal discussion). No Board member participates in the hearings, which calls into question the depth of the Board members’ understanding of the issues they are called on to decide.
From the perspective of local property owners, who strongly object to the placement of wind farms near their homes and property, we must spend our time and our own money to do the job that the OPSB should be doing for the public and yet we feel we are being undercut by the OPSB at every turn. The net result of OPSB actions works to effectively deprive us of any meaningful opportunity to be heard. At the same time, the OPSB is issuing, over the strong objections of local property owners and local government officials, more certificates authorizing the construction of new industrial wind facilities that intend to violate the minimum setback requirements in current law. In other cases, the OPSB is allowing certificated wind farms to evade the General Assembly’s new setback requirements by improperly extending the life of those certificates before the effective date of the setback requirements.
Contrary to the statutory requirements enacted by the General Assembly, the OPSB is complicit in and protective of unfair and unreasonable wind industry practices. Examples include:
- Permitting legal notice of public hearings to appear at times when the public is least likely to see them;
- Scheduling public hearings at times the public is least able to attend;
- Allowing wind companies to conduct required pubic information meetings without specifying the location of proposed wind turbines;
- Allowing wind companies to meet the Board’s public notification requirements using maps that lack necessary detail, such as roads or parcel boundaries, to enable landowners to assess the potential impact on their properties;
- Enabling wind companies to negotiate unfair and one–sided contracts that obligate the signer to waive impacts they often do not understand; that burden the entirety of a property for up to 45 years; that are negotiated using a divide and conquer strategy ; that include no right of rescission; and that include onerous and overbroad confidentiality clauses. Oftentimes, the property owner is elderly and may not be in a position to understand or negotiate in his or her best interest.
- Failing to establish clear and enforceable standards for audible noise and instead allowing the use of vague “design goals” that fail to consider worst-case impacts;
- Failure to establish any standards at all for inaudible low frequency noise emissions;
- Refusing to consider a report from a Wisconsin power siting proceeding that cited new scientific findings regarding low frequency noise from wind turbines and concluded that there is now enough evidence to classify low-frequency noise and infrasound from wind turbines as “a serious issue, possibly affecting the future of the wind industry.”
- Failing to require that setback waivers be obtained from all adjacent property owners as required by law;
- Failing to require wind developers to specifically articulate the alleged benefits accruing to the described project area and, instead, accepting alleged benefit claims that pertain to unrelated and distant communities even though the impact/burden of the project is borne by the local property owners;
- Failing to accord due weight to local governments who object to applications on the basis of harms to the community’s economic health and welfare or cultural identity;
- Failing to adopt rules for siting industrial wind turbines near public and private recreational areas, including Indian Lake as well as numerous golf courses and equestrian facilities;
- Extending certificate expiration dates without following the statutory requirements for amendment of certificates, such as the requirements for investigation by the OPSB staff and for public hearing to consider substantive changes in the assumptions underlying the original certificate (chief among these changes is the dramatic increase in blade length which increases vibration and low frequency emissions as well as recent medical studies concerning related health effects);
- Failing to consider cumulative impacts in areas where multiple projects are sited;
- Failing to require developers to establish a complaint resolution protocol acceptable to the community prior to issuing a certificate; and
- Blaming insufficient funding/lack of resources to fully carry out their duties.
As the Ohio Supreme Court has stated, “It is axiomatic that the federal and Ohio constitutions forbid the state to take private property for the sole benefit of a private individual.” Norwood v. Horney (2006), 110 Ohio St.3d 353, 365. Yet that is exactly what the Power Siting Board has repeatedly permitted to occur. The constitutionally protected property rights of Ohioans are being harmed in favor of industrial wind development. These massive industrial power plants are being imposed in rural residential communities by private for-profit developers. The developments are structured as limited liability
companies owned more often than not by foreign private equity firms. These massive industrial power plants are not public utilities and are not empowered with the right of eminent domain but through the faulty administration of the law by the Ohio Power Siting Board that is effectively the result. Ohio’s administration of wind power development is unregulated under the guise of regulation.
We request that you halt further consideration of any active industrial wind power siting case until lawful rules are established, eliminate the exemption from rulemaking due process currently afforded to the Ohio Power Siting Board under Revised Code Chapter 119, and require that any application for certificate amendment or extension be subjected to the due process of meaningful public notice, a full investigation, and a fair hearing. If the State of Ohio is unable to administer a fair regulatory program that protects her citizens, siting decisions must be returned to local zoning and control.
Should you have any questions or require additional information, please contact Julie Johnson at juliejohnson/ctcn.net or call 614-284-6151. Thank you for your consideration.
Signed by Residents of Ohio [Whose Names and Addresses Were Attached Hereto]
November 11, 2014
TO: Governor John Kasich
State of Ohio
Riffe Center, 30th Floor
77 South High Street
Columbus, OH 43215-6117
Lt. Governor Mary Taylor
Senator Keith Faber, President, Ohio Senate
Speaker William Batchelder, Ohio House of Representatives
Senator William Seitz, Chairman, Senate Public Utilities Committee, Ohio Senate
Rep. Peter Stautberg, Chairman, House Public Utilities Committee
Chairman Tom Johnson, Public Utilities Commission of Ohio