Beware of Falling Wind Turbine Blades !

(Note: Luckily no one was killed, as these blades are as big as the wing span of a 747 and can turn at speeds of 160 KPH or more. And if the blades hit the tower, they self destruct and can scatter over a large distance. A setback of 550 metres won't be enough for anyone living next to a self destructing wind turbine. See examples on Youtube.)


http://www.kcrg.com/news/local/North-Dakota-Wind-Farm-Operating-Again-After-Blades-Fall-From-Tower-118425929.html

BISMARCK, N.D. (AP) — A wind energy project in north-central North Dakota has resumed generating power, a spokeswoman said Monday, a week after the rotor and three giant blades on one of its towers plummeted to the ground.


The wind farm has 71 turbines perched atop steel towers just north of Rugby, about 150 miles northeast of Bismarck, and is capable of generating up to 149 megawatts of electricity. It was inspected after the March 14 accident and judged to be safe to resume operation, said Jan Johnson, a spokeswoman for Iberdrola Renewables Inc. in Portland, Ore.

Johnson said an investigation into the cause of the accident has not been completed. In a letter to North Dakota's Public Service Commission, Sarah Emery, an Iberdrola senior permitting manager, said the tower suffered a "rotor assembly failure."

No one was injured. The Public Service Commission, which approved the wind project's site plan, expects to be briefed at its meeting Thursday about the accident, Commissioner Brian Kalk said.

The wind turbine's manufacturer, Suzlon Wind Energy Corp., described the mishap as "an isolated incident."
"Suzlon has complete confidence in the safe operation of our fleet of 7,600 wind turbines worldwide," the company's statement said.

Iberdrola's parent company is based in Valencia, Spain. Suzlon Wind Energy Corp. is a unit of Suzlon Energy Ltd., based in India.

North Dakota had more than 1,400 megawatts of wind generating capacity at the end of last year, which ranked it ninth among states, according to the American Wind Energy Association, a trade group. The association says North Dakota has enough wind energy to power 430,000 homes.

The Iberdrola wind farm sells its energy to Missouri River Energy Services, based in Sioux Falls, S.D., which supplies electricity to 60 municipal utilities in North Dakota, South Dakota, Minnesota and Iowa.

Missouri River's North Dakota members include the cities of Cavalier, Hillsboro, Lakota, Northwood, Riverdale and Valley City.