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With tens of thousands in operation across the world, wind turbines have demonstrated an excellent safety track record. Primary safety issues of concern are the icing of the blades and resulting shedding of the ice and the potential impact of a blade throw.
Ice Shedding
Under certain conditions in climates such as those found in New England, ice can accumulate on wind turbine blades. The release of that ice from moving turbine blades is possible. (The potential is clearly highest at mountain-top sites, remote from most observers in the harshest of weather.) A wind installation typically addresses such possibilities by employing adequate setbacks between each turbine and any nearby residences to avoid risk. Severe ice buildup will lead to automatic turbine shut down until the condition improves. Modern turbines can be equipped with cold weather packages, which make them adaptable to temperatures as low as -40 Celsius, reducing the risk of ice accumulation. These packages include special coatings on the blades to eliminate the adherence of ice, thermostat-controlled resistive element forced air heaters strategically placed to heat instruments and operating components during cold weather conditions to prevent the formation and adherence of ice, and low-temperature lubricants. No studies have been conducted in the United States concerning ice shedding from wind turbine blades. The 1998 European study, "Assessment of Safety Risks Arising from Wind Turbine Icing" (PDF 57 KB) Download Adobe Reader by European Commission, DGXII, and the UK Department of Trade and Industry examines the issue as well as the study "Risk Analysis of Ice Throw From Wind Turbines" (PDF 297 KB) Download Adobe Reader presented in April 2003 at BOREAS conference in Finland.
Blade Throws
Modern wind turbines are reliable, safe, state-of-the-art power plants with hundreds of thousands of hours of operating experience. Commercial turbines are equipped with sensors and are mechanically robust such that blade throws are virtually non-existent.
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