Documents filed under Shadow Flicker
The Polish National Institute of Public Health has filed this opinion regarding the construction of industrial wind energy facilities in close proximity to residential areas.
This lawsuit filed against Consumers Energy Company, owner of the Lake Winds Energy Park consisting of fifty-six Vestas V100 1.8 megawatt turbines with a total installed capacity of 100.8 megawatts. An excerpt of the complaint is provided below. The full complaint can be accessed by clicking on the links at the bottom of this page.
There is no worldwide agreement on appropriate wind turbine setback distances from homes and limited awareness of wind turbine setbacks in other countries. This report attempts to identify and clarify existing governmental requirements and recommendations regarding wind turbine setbacks from residences. The introduction of the report is provided below. The full report can be accessed by clicking the link(s) on this page.
This suit was filed against the Village of Libertyville (IL) and DPR Investments LLC shortly after a business-scale wind turbine was erected and became operational within 600 feet of residential properties. The Entegrity 50 kilowatt, 120-foot turbine is owned by DPR Investments doing business as Aldridge Electric Company. Complaints of noise, shadow flicker and blade flicker were heard right after the turbine started turning. On July 24, 2009, the Court issued a compromise ruling stating that the turbine was affecting neighboring residents and restricted the turbine hours of operation to weekdays from 9 a.m. to 3 p.m. (see: http://www.windaction.org/news/22373 )
In late February 2009 the Minnesota Department of Health (MDH) received a request from the Office of Energy Security (OES) in the Minnesota Department of Commerce, for a “white paper” evaluating possible health effects associated with low frequency vibrations and sound arising from large wind energy conversion systems (LWECS). MDH agreed to evaluate health impacts from wind turbine noise and low frequency vibrations. In discussion with OES, MDH also proposed to examine experiences and policies of other states and countries. Below are the Introduction and Conclusions of the white paper released in May 2009. The full report can be accessed by clicking on the link at the bottom of this page.
Wind turbines are known to produce shadow flicker by interruption of sunlight by the turbine blades. Known parameters of the seizure provoking effect of flicker, i.e., contrast, frequency, mark-space ratio, retinal area stimulated and percentage of visual cortex involved were applied to wind turbine features. The proportion of patients affected by viewing wind turbines expressed as distance in multiples of the hub height of the turbine showed that seizure risk does not decrease significantly until the distance exceeds 100 times the hub height. Since risk does not diminish with viewing distance, flash frequency is therefore the critical factor and should be kept to a maximum of three per second, i.e., sixty revolutions per minute for a three-bladed turbine. On wind farms the shadows cast by one turbine on another should not be viewable by the public if the cumulative flash rate exceeds three per second. Turbine blades should not be reflective.
Large scale shadow flicker is a phenomenon, not experienced by people on an “industrial scale”, with football field-sized shadows moving across their home or through their local views. This report prepared by physicist Rick Bolton examines the problems with the shadow flicker modeling at a proposed site in New York State. A portion of the report is provided below. The full report can be accessed by clicking the link on this page.