Shadow Flicker

Shadow flicker is caused by the sun rising or setting behind the rotating blades of a turbine. The shadow created by the rotating blades can cause alternating light and dark shadows to be cast on roads or nearby premises, including the windows of residences, resulting in distraction and annoyance to the residents. A related phenomenon, strobe effect, is caused by the chopping of sunlight behind moving blades, similar to the effect of the setting sun behind trees when driving along a roadway in the winter. Both of these phenomena are factors in the visual impact of a wind turbine project, and some argue that they are a threat to health and safety. They could also be considered a nuisance to nearby property owners.

Ice throw is a concern related to the fact that any object at the end of the rotating blades is traveling at a high rate of speed. In the case of a 60 meter turbine (about 200’ diameter), rotating at 20 RPM, the tip of the blade is traveling at just over 140 mph. If the turbine diameter increases to 80 meters, the tip speed increases to just over 187 mph. There are reports of ice having accumulated at the tip of the turbine and upon breaking loose, traveling significant distance......

A Landscape Classification System report, maps and GIS files is now available as an aide to "environmentally responsible siting of utility-scale wind projects in Virgina." The report and associated materials was a collaborative product of Dan Boone, Judy Dunscomb, Rick Webb and Christina Wulf, who worked on this project on behalf of The Nature Conservancy, Virginia Society of Ornithology and Virginia Forest Watch.

Rick Webb and Dan Boone have created a website - www.VAwind.org - to disseminate this report and related information. They "are guided by the Precautionary Principal, wherein if we have reasonable suspicion of harm, accompanied by scientific uncertainty, then we all have a duty to take action to prevent harm." They "remain hopeful that the wind industry will embrace the principle of precaution and stand as a role-model for other industries by taking strong and proactive steps to prevent environmental harm" and "intend to continue work on the Landscape Classification System and to promote effective assessment of environmental issues related to wind energy development."

Eric Rosenbloom's list of the current industrial-scale wind projects targeted for Vermont. Note the huge leap in size from the existing Searsburg facility that we are all urged to go see and love and consequently love as well the new very much larger facilities being planned.

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 )

Although Texas leads the nation in wind development, you may be surprised to learn that Texas law concerning the wind is basically non-existent. Similarly, there is little to no statutory regulation of the industry. So far, wind farms have been located in remote rural settings; however, as wind turbine technology advances and the land and wind speed necessary for the efficient development of wind energy decreases (and becomes even more profitable), it will not be long before the fight over wind finds itself deeply entrenched in Texas courts. ...While water law and the law governing the rights of wild animals may help resolve the issue of wind ownership, the question remains as to whether the right to develop the wind is a right that is severable from the land. In looking for guidance, the state courts may choose to rely on an area of the law with which they are quite familiar: oil and gas law. It is well established in Texas that the mineral estate (i.e., oil, gas and other minerals) may be conveyed and reserved apart from the surface. Texas courts have also held that certain substances which are historically considered part of the surface estate (such as near surface lignite and gravel, as examples) may be severed from the surface estate.

Environmental groups and residents of Nevada have filed a complaint in U.S. District Court of Nevada challenging the Department of the Interior's permit granting Duke Energy permission to construct an 87-turbine wind energy facility east of Searchlight on 19,000 acres of Bureau of Land Management land. Excerpts of the complaint are provided below. The plaintiffs argue that Former Interior Secretary Ken Salazar acted in a manner that was arbitrary, capricious, an abuse of discretion and contrary to law. The full complaint can be accessed by clicking on the link(s) at the bottom of this page.