Posted on 06/15/2014 3:27:11 PM PDT by PoloSec
A team of storm chasers from Tea, South Dakota, spotted a wind turbine damaged by a lightning strike ear Ruthton, Minnesota. The Tea Storm Chasers gave me permission to post the image here.
The only wind farm I can find in the area is relatively old. The Ruthton Wind Farm went online in 2001. It's operated by Xcel, a large utility.
One thing we do know: Lightning strikes on wind turbines happen frequently. A 2007 journal paper on lightning protection for wind turbines reported that lightning damage is the "the single largest cause of unplanned downtime in wind turbines."
(Excerpt) Read more at theatlantic.com ...
I don’t believe I’ve ever seen one, or a picture of one, with the obvious need: a lightning rod.
Needs viagra
“Lightning strikes on wind turbines happen frequently.”
Naturally, that will not be factored into the publicized cost of wind power.
Lightning’s powerful. I’ve seen some huge oil fires caused by lightning.
Not so easy to design. The arms are huge so a rod up the center was probably there and insufficient.
That plane is going down...
This is more common than you think.
Since the blades are made in two halves are then bonded together it splits the blade like a banana.
I have worked on several dozen lightening failures.
This is a lubrication failure.
Either they did not change the oil often enough or the oil pan gasket failed which is unlikely.
The smoke is from an oil fire.
Agreed.
I’m guessing a lighting rod would have to stick-up pretty high above the blades in order to work. They’re probably more worried about it breaking off and damaging the blades. I think the blades are made out of carbon fiber, so not cheap.
Even a token lightning rod would be easy to spot, though. I’ve seen diagrams of the “cone of protection” furnished by a rod. What rods often do with their sharp pointed tips is attract and drain away the electrical corona leaders that spawn lightning strikes, before a full strike can form. The adage remains true that “if lightning wants to strike you it will.” The paths of lightning can be crazily chaotic. But usually rods will help a situation or at the least redirect most of an actual strike.
Just look at how amazing wind turbines are at cleaning up the environment. In that picture, see how the pollution (going from right to left because of the wind) is just sucked up by the wind turbine on the left. For some reason the one on the right is off line and is not removing pollution. But look at that left one just suck it out of the air, leaving pure air downwind of the turbine!
Wait, the wind is going which way?
The tree huggers fail to also mention what the impact is to local bird populations.
Indeed! Ben Franklin figured out the solution 200+ years ago. Why aren't today's design engineers using it???
Why put the rods in the arms?? Mount'em on the nacelle behind the prop arms. They just have to extend up higher than the prop arm length, which shouldn't be too difficult.
If you run the rod through the nacelle center of rotation around the tower, it is a direct shot straight to ground.
Modern wind turbines do indeed have various types of lightning protection. Because of wind turbine complexity, simple lightning rods aren’t so effective.
Blades have conducting tips and grounding, for example.
Since the blades move in operation, that may make conventional lightning protection strategies more difficult. Lightning often takes several seconds to form before there is what we call a strike. So what has bled off charge from the air where the blade had been, may not have bled it off from the region where the blade is now. I’d still think a tall single rod up the center could help, or maybe tall single rods on towers standing amidst a field of turbines, but I guess the designers don’t agree or have figured it is not worth the cost based on the loss rate of turbines.
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