Wind Energy Run Amok

Very impressive... but most over speed failures are...

Looks like a bit of R&D, if thats what happens when there is only one, lets hope it does not happen in a crowd.

Regards JD.

If you listen carefully you can hear at least one more running in the background after the first one self destructs. Makes me wonder why they were filming this one.

I agree, the same though passed my mind. But must admit I did not hear the other one in the back ground. Hopefully a lesson was learnt along the way. Must also admit to not reading the second link and inquiry regarding the failure. but it still looks like an opportunity to do some R&D.

Regards JD.

I suspect that they knew that the overspeed controls weren't working on this one, and the storm happened before they could fix it - so they knew there was a chance it would fail. It was not a deliberate test, as the article referenced in the original post points out.

As to the comment about the reliability of wind power (#3 below) - storms generally do not bother wind turbines (this one was 10 years old). This one clearly had a malfunction. Malfunctions, including overspeed failures, happen on conventional power turbines as well, and they can be even more impressive because there's flammable fuel involved!

Makes one wonder how reliable wind power really is. A big storm and your power supply disappears for who knows how long.

Wind turbines have two common methods of overspeed protection, one being to adjust blade pitch, and the other being to turn the nacelle perpendicular to the wind.

This turbine did neither. Given that they were filming it from a safe distance, and that the cameraman didn't fall over when it exploded, my guess is that this was a deliberate test to failure, perhaps a re-enactment of the original accidental failures.

Otherwise, how would they know which one to film out of thousands?

Hello Munky, nice to see someone contributing from the North - close by, where windpower is increasingly being used.

As per some of the previous comments it seems that this one was filmed due to the fact that the overspeed protection was inactive. What I found most interesting when watching the Video were 2 factors:

1: The structure collapsed after the blades had presumably deflected so much that they hit the base pole of the assembly - can anyone confirm or deny that?

This would conclude that a greater factor of safety could simply be achieved by giving more space for deflection.

2: The pole base structure seems to have been made from fibreglass - pictures after it was torn apart. Is this common? I was under the impression that these structures were steel? of course this being on another continent may constitute different requirements - ie tornadoes in the USA and Hurricane like forces and the rare low end Tornado in Canada.

Definitely an R&D opportunity - any government funding?

Mirco, Newmarket, Ontario, Canada.

It should have automatic locking of the blades in case of overspeeding. If blades are locked wind could have simply passed by. The trearing of blades was due to very high rotation.

Two things concern me regarding reliance on wind power generation for electricity.

1. No wind for lengthy periods of time........even though sites for wind farms are selected for their consistency of wind conditions now.

2. As shown in the video, severe storms causing destruction of wind farms.

My reason for stating these points as a generality is climate change, it seems that nobody can predict what is going to happen to the weather.

I personally feel that we need a more reliable source for the generation of electricity.

With regard to point 1): No one solution is going to take the place of petroleum as a primary energy source. Future energy systems will aggregate many different input sources, one of which will be the wind.

With regard to point 2): As mentioned in previously, this turbine was 10 years old (i.e., had weathered 10 years worth of storms). Wind turbines are generally well designed and not susceptible to severe damage from storms. There have been many large scale wind farms in operation for ~20+ years. The Altamont pass wind farm in California has been running since the '70s. Notice that we have not seen news stories about these wind farms being destroyed by storms. This was an isolated incident of one turbine in a farm that had an overspeed protection system failure.

Hi,

if at failure only one blade fails first then the other two will put so much centrifugal force on the tower that I think it very likely that the tower will bend and fail and then the two other blades will fail because of the movement of their attachment structure.

This may be pretty fast as I cannot detect anything like this in the film.

How much impulse will the tower survive?

I saw new wind turbines built recently , some have a structure like the masts of 300KV power transmission lines: made from screwed together individual bars (zinc coated), not welded as corrosion protection seems to be much more difficult if welded.

Some others have concrete rings glued! to the next ring with steel anchors from one to the next. The biggest rings near the base come in two halves as transport on existing streets is limiting the size.

Still others have massive steel rings as a base linked to a big (18m x 18m x 1m) concrete base heavily reinforced with steel. I estimate that these will be totally from steel when completed (takes some more 4 to 6 months).

All these will have shaft heights of 100m or more and max power ratings above 1MW.

What about fail-safe design of the speed limiting mechanisms? Does any body know about the implementation? Simply 2 independent?

RHABE