Wind Turbine De-Icing.

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Wind Turbine De-Icing.

#1 Post by barkingmad » Mon Dec 02, 2019 2:17 pm

December UK and freezing fog with a breeze is forecast for 03/12.

Does anyone know how the wind turbine ‘wings’ cope with icing conditions or do the assemblies have imbalance detectors which would cause auto-shutdown if vibes are excessive due asymmetric icing or structural failure?

I’ve also noticed strakes and winglets on these blades as I struggle past them on my ancient bike atop a local hill. (Idiot!)

Doubtless they accrete ice in freezing fog/low cloud conditions with breeze and then there may be some mechanical shedding of ice, a danger which has presumably been assessed as negligible to passing road users or farm workers.

Also rather strange that above certain wind velocities they have to be shut down. I would have thought that some element of partial “feathering”, full feathering being evident on most of them when they’re stationary, would prevent too much energy being absorbed by the generators and exceeding the specified output rating. I have wondered if it’s an orographic turbulence factor which might cause damage to the rotating assembly. :-\

Yes, I know, I really must get out more, but that’s where the query first swam into my idle brain as the CO2 built in the leg muscles! !

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Re: Wind Turbine De-Icing.

#2 Post by ribrash » Mon Dec 02, 2019 3:17 pm

My friends son works on the wind farms out in Liverpool Bay.They have teams of technicians who are dropped off each day to carry out maintainance etc. My mates son is part of an absailing team that checks the blades for damage,particularly lightening strikes.
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Re: Wind Turbine De-Icing.

#3 Post by Pontius Navigator » Mon Dec 02, 2019 8:54 pm

I have certainly heard of ice being flung off. Despite the length of each blade I don't think they throw very far.

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Re: Wind Turbine De-Icing.

#4 Post by Pontius Navigator » Mon Dec 02, 2019 8:58 pm

Answers here;

https://www.windpowerengineering.com/cr ... ne-blades/

Seems ice can get thrown a third of a mile.

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Re: Wind Turbine De-Icing.

#5 Post by Smeagol » Wed Dec 04, 2019 11:20 pm

barkingmad wrote:
Mon Dec 02, 2019 2:17 pm
December UK and freezing fog with a breeze is forecast for 03/12.

Does anyone know how the wind turbine ‘wings’ cope with icing conditions or do the assemblies have imbalance detectors which would cause auto-shutdown if vibes are excessive due asymmetric icing or structural failure?

I’ve also noticed strakes and winglets on these blades as I struggle past them on my ancient bike atop a local hill. (Idiot!)

Doubtless they accrete ice in freezing fog/low cloud conditions with breeze and then there may be some mechanical shedding of ice, a danger which has presumably been assessed as negligible to passing road users or farm workers.

Also rather strange that above certain wind velocities they have to be shut down. I would have thought that some element of partial “feathering”, full feathering being evident on most of them when they’re stationary, would prevent too much energy being absorbed by the generators and exceeding the specified output rating. I have wondered if it’s an orographic turbulence factor which might cause damage to the rotating assembly. :-\

Yes, I know, I really must get out more, but that’s where the query first swam into my idle brain as the CO2 built in the leg muscles! !
I have been involved in constructing wind farms for the last 15 years, but all of them offshore so on the last point ,'orographic turbulence', has never been a factor. I am not an expert in WTG design or maintenance, project management of the overall construction activities was my role.

Regarding icing, I am not aware of it being a specific problem requiring specialist monitoring to prevent imbalance issues being a problem. The blades of modern WTGs are VERY large and pretty heavy so ice formation may not make a sufficient difference to become problematical. I'm guessing here but will ask an expert and give some feedback if anyone is interested.

As for shutting down in high wind velocities, this is universal, with blades being gradually feathered as velocities increase to prevent overloading of the structure. From memory on earlier WTGs, power output ramps up from about 4m/s (below that nothing much is produced) up to when maximum power is generated at around 13m/s up to 25m/s after which the machine is shutdown. This may be different now as my knowledge was on machines about 10 years ago.

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Re: Wind Turbine De-Icing.

#6 Post by G~Man » Thu Dec 05, 2019 12:30 am

2vwe38.jpg
2vwe38.jpg (73.11 KiB) Viewed 79 times
B-) Life may not be the party you hoped for, but while you're here, you may as well dance. B-)

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Re: Wind Turbine De-Icing.

#7 Post by llondel » Thu Dec 05, 2019 12:53 am

"wind turbine overspeed" is an interesting search term on YouTube.

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Re: Wind Turbine De-Icing.

#8 Post by Rwy in Sight » Thu Dec 05, 2019 6:25 am

Smeagol, we are looking forward to hear from your expert. To all why they don't put de-icing boots on the blades? And why they don't try to adjust the feathering to extend the wind speeds they operate?

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Re: Wind Turbine De-Icing.

#9 Post by G-CPTN » Thu Dec 05, 2019 7:15 am

G~Man wrote:
Thu Dec 05, 2019 12:30 am
2vwe38.jpg
Yes, indeed!

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Re: Wind Turbine De-Icing.

#10 Post by llondel » Thu Dec 05, 2019 5:24 pm

On a similar note, I'm wondering whether I need to get on a ladder and clean the solar panels on the roof. Can't quite justify using a helicopter to do it.

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Re: Wind Turbine De-Icing.

#11 Post by Rwy in Sight » Thu Dec 05, 2019 8:11 pm

I think there is the issue of distance. Most roofs are much lower than the blades.

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