Library filed under Safety
Britain The Times April 16, 2005 Wind farm fears as blade snaps By Katrina Tweedie A TURBINE at a Scottish wind farm has broken down after one of its blades snapped off. The 10-tonne turbine, one of 31 at the £80 million Crystal Rig wind farm near Dunbar, East Lothian, was destroyed last week when a mechanism to stop it spinning too fast failed. Onlookers reported strong winds and said one of the turbine blades flew off and hurtled into the countryside. The 60ft high steel turbines are designed to withstand wind speeds of up to 60 miles per hour and owners, Fred Olsen Renewables, denied the breakdown was wind related. A spokesman said they were investigating the cause and that there had been little risk to people at the remote wind farm. The turbines from German firm Nordex were installed in August 2004. It will cost an estimated £1.25 million to repair. Anti-wind farm campaigners said the incident confirmed their fears about the danger of blades flying off wind turbines. David Bruce, of the pressure group Scottish Wind Assessment Project, said: “There were high winds so the turbines were ‘feathered’, or locked so they couldn’t spin round. It was lucky nobody was walking below. This is only about the second incidence of this in the UK but it shows this is possible.”
In many parts of the country, wind farms are being installed to alleviate the need to build more electrical generating plants. These wind farms can have a profound effect on your public safety, utility, and governmental microwave systems by chopping and reflecting the microwave beam.
Dr. Terry Matilsky, Associate Professor of physics and astronomy at Rutgers University, addresses ice throws on behalf of the Kingdom Commons Group's opposition to the proposed East Haven Windfarm.
In the beginning of the nineties, ECN and consultants in the Netherlands were approached by local authorities and developers of wind farms with the question: “Is it safe to erect a wind turbine at this location?”
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......
3.8 Health & Safety Affected Environment, Environmental Impacts and Mitigation Measures "A number of comments submitted for the scoping process for the Desert Claim project EIS addressed concerns relating to potential health and safety issues. Specific topics indicated in these comments included certain possible hazards that are uniquely associated with wind turbines, such as blade throw and ice throw; health and safety issues associated with electrical and magnetic fields; more common hazards such as fire; and the incidence and impacts of shadow flicker, another phenomenon specific to wind turbines. Section 3.8 addresses these wide-ranging health and safety topics that have been identified as concerns for the environmental review. "
Catharine Lawton's letter to the attorney representing Addison Wind Energy on the developer's failure to represent accurately a number of the dangers associated with icing of the blades of industrial wind turbines.
Typhoon Maemi struck Miyakojima Island on September 11, 2003 with an average wind speed of 38.4m/s and a maximum gust of 74.1m/s, recorded at Miyakojima meteorological station. All six wind turbines operated by Okinawa Electric Power Company were extensively damaged. Two Micon M750/400kW turbines collapsed by the buckling of the towers and one Enercon E40/500kW turbine turned over due to the destruction of the foundation. The other three experienced broken blades and damaged nacelle covers.
A man walks near a demolished wind turbine in Goldenstedt, nortwestern Germany, Monday Oct. 28, 2002. The 70 meter (230 foot) high turbine fell during the heavy storms that hit Germany.
ADVISORY CIRCULAR: AC 70/7460-1K Obstruction Marking and Lighting-- This change amends the Federal Aviation Administration’s (FAA) standards for marking and lighting structures to promote aviation safety. This change is effective August 1, 2000.....A sponsor proposing any type of construction or alteration of a structure that may affect the National Airspace System (NAS) is required under the provisions of 14 Code of Federal Regulations (14 CFR part 77) to notify the FAA by completing the Notice of Proposed Construction or Alteration form (FAA Form 7460-1). The form should be sent to the FAA Regional Air Traffic Division office having jurisdiction over the area where the planned construction or alteration would be located.
"This paper provides an overview of the issues affecting wind turbine operations in cold weather with a special emphasis given on atmospheric conditions prevailing in the Northeast United States. The first section describes previous and more recent wind energy projects in cold weather areas. In the second section, environmental elements most likely to impact on the operation of wind turbines in cold weather are introduced: low temperatures, icing and snow. It also presents various climatic situations and their specific behavior in cold weather. The third section suggests some solutions to problems identified in the previous section. In addition, this paper suggests ideas of further research on the operation of wind turbines in cold climate. It also identifies organizations interested by similar issues whose cooperation would be beneficial."
"Developers and owners of wind turbines have a duty to ensure the safety of the general public and their own staff. However, there are currently no guidelines for dealing with potential dangers arising from ice thrown off wind turbines. This puts developers, owners, planning authorities and insurers in a difficult position. To rectify this situation, the work presented here has commenced in order to produce an authoritative set of guidelines. Initial work has resulted in the development of a risk assessment methodology which has been used to demonstrate that the risk of being struck by ice thrown from a turbine is diminishingly small at distances greater than approximately 250 m from the turbine in a climate where moderate icing occurs."