Why did a Scottish wind turbine explode in high winds?

[phantom power]

Not again

This striking image of a wind turbine in Ardrossan, North Ayrshire, Scotland as it exploded in high winds has made headline news. The turbine was destroyed yesterday as the region was battered by winds of up to 260km/h when a ferocious Atlantic storm powered into northern parts of the UK. But what caused the explosion?

An amateur video shows the turbine head spinning on its axis and one turbine blade apparently losing its carbon composite skin before the fire starts.

It's not yet clear what happened, but attention is likely to focus on the turbine's ability to shut itself down in high wind. A wind turbine normally shuts down when winds reach 55 mph - but something clearly went awry in Ardrossan, perhaps causing excess current in the generator windings, which may have led to the fire.

The shutdown is normally performed by 'feathering' the turbine blades so they do not turn. "In general the turbine blades will pitch out in high winds, keeping the turbines in idle mode," confirms a spokesman for the turbine's manufacturer, Vestas of Aarhus, Denmark.

Another source of the problem may be a fault in the turbine's gearbox, which ensures the rotor speed is adjusted so that the generator provides electricity that matches what is required by the grid it is feeding.

http://www.newscientist.com/blogs/onepercent/2011/12/why-did-a-wind-turbine-self-co.html

[DainBramaged]

1. Shit happens....

[dipsydoodle]

2. If you root around

I think you may find that the gearboxes are the weakest point in those.

[jpak]

3. millions dead

to coin a phrase

:evilgrin:

[phantom power]

13. I was going to title the post "Scotland has a wind power event"

:hi:

[Motown_Johnny]

4. because exploding in low winds would have been embarrassing

gearbox seems like a reasonable explanation to me

[OKIsItJustMe]

5. I notice it’s facing in the opposite direction (relative to its companions)

I wonder if that is significant.

[Tesha]

6. How much electromagnetic radiation was released? For how many centuries...

...will people have to avoid the site? How many trillions
of Pounds will the remediation cost?

Tesha

[WingDinger]

7. The video shows that the wind tries to spin the head around, SOOOOOOOOO

If I were to design these, I would put the prop on the backside, and use the wind to keep it pointed into it. Then, it wouldnt need a gearbox to do so.

Also, I would make it a tripod stand.

[Bob Wallace]

10. Been done...

It's much more efficient to actively adjust turbine direction than to do it passively with a vane.

With lidar (radar that can see the wind coming) turbines are able to align themselves before the wind switches. And gears keep turbines firmly pointed toward the wind rather than oscillating and spilling wind.

The gearboxes that cause problems are not the gears that orient the turbine, they are the gears used to change the shaft speed between blades and generator. Lots of rapidly spinning gears and lubrication systems can fail causing gears to heat.

Some turbines are now being built without gearboxes, mostly for offshore use. Not having a gearbox means less maintenance work which is more expensive at sea.

[OKIsItJustMe]

12. Well, the base doesn’t seem to have broken

It appears your tripod may not be necessary.

[WingDinger]

20. The amount of engineering, to make it a single sexy mast, and the materials needed,

are part of the equation of when wind is justified.

[HelenWheels]

8. Made in China???? nt

[Bob Wallace]

11. Vestas turbines...

Danish company.

Turbines at this site made in a Argyll, Scotland factory.

[FBaggins]

9. Hurricane-force winds will do that to lots of manmade objects

That's just the nature of the beast.

The impressive thing is that the other units appear to have survived.

[phantom power]

14. it would not be hard for me to imagine this exchange:

"Should we design these wind turbines for a category V hurricane?"

"What on earth for, you gormless git?"

[FBaggins]

15. Sounds like a reasonable conversation - depending on the location.

If it costs 25% more to build one that can take a Cat5 than one that has a 10% chance of failure... and only one in 100 will even see such a storm... it doesn't make sense to overbuild them. Better to just insure them.

[Bob Wallace]

16. I'd be surprised...

if these turbines were "under-built". Right now the turbine market is not enormous and I doubt that there is much variation in models available. It's more likely a 'one size fits all'.

Companies are just starting to come out with turbines designed for locations with lower wind speeds.

[FBaggins]

17. Actually, they aren't "one size fits all"

"Survival speed" is a standard design factor for turbines. They range from right around a Cat1 storm to right around where this storm reportedly reached (essentially a Cat5).

The most common is around Cat3 strength, so these units were pretty well built.

[kristopher]

18. Class I, II, and III

Vast majority are class II, class I are for harsh severe climates and class III are for low wind speed applications.

[Bob Wallace]

19. OK, I'm surprised...

And corrected.

Thanks.

[nostalgicaboutmyfutr]

21. Oh, my god......

the humanity of all that spilt wind across the Scottish landscape!!!

How can they ever recover from this environmental catastrophe......