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The world’s largest wind turbine has been switched on

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Re: The world’s largest wind turbine has been switched on

#31

Post by pengaru »

bluGill wrote: post #22
pengaru wrote: post #13

Earlier quoted context omitted.

I presume the pitch is adjustable, so unless the mechanism fails you can just relax the pitch like pointing a sailboat directly into the wind to depower the sails.

The mechanism is designed (or at least should be designed) so that if anything breaks the blades rotate to the no power position. There is a lot of engineering and redundancy that i'm only partially aware of.

I guess the real question is how bad can conditions get before the "no power position" is still too much force for the structure to withstand.

You can't escape the fact that the blades are a ton of surface area on a long lever... and if the winds are both forceful and directionally chaotic, there isn't really a "no power position" to be found.

Going back to the sailboat metaphor, it's the conditions where you douse the sails entirely. At most flying a little storm jib. Pointing upwind is just to enable doing so.

Re: The world’s largest wind turbine has been switched on

#32

Post by Qem »

throwbadubadu wrote: post #25
windows2020 wrote: post #12

I wonder what paint job would best prevent birds from being destroyed by this. It looks like sometimes one blade is painted black for this purpose. How do bird deaths from wind turbines compare to other manmade objects?

Insignificant on many levels. If we should care for that we should stop all fossil fuel consumption right now, stop eating meat, and most importantly, stop putting glass windows into our cute buildings. Why are these questions always in wind turbine posts before anything els?

> Why are these questions always in wind turbine posts before anything els?

Because it's better to worry about it and try to mitigate at the beginning, than wait until there is too much inertia, sunken costs, vested interests and institutional pushback. Some things become too hard to fix if you start wrong.

Re: The world’s largest wind turbine has been switched on

#33

Post by el_benhameen »

throwbadubadu wrote: post #25
windows2020 wrote: post #12

I wonder what paint job would best prevent birds from being destroyed by this. It looks like sometimes one blade is painted black for this purpose. How do bird deaths from wind turbines compare to other manmade objects?

Insignificant on many levels. If we should care for that we should stop all fossil fuel consumption right now, stop eating meat, and most importantly, stop putting glass windows into our cute buildings. Why are these questions always in wind turbine posts before anything els?

Folks who worry about this have an excellent outlet for their concerns: don’t have outdoor cats, and donate and work to spay and neuter feral outdoor cats. They are orders of magnitude more destructive to the bird population than wind turbines will ever be.

Re: The world’s largest wind turbine has been switched on

#34

Post by karmakurtisaani »

Qem wrote: post #11
ninkendo wrote: post #5

123 meter blades, that’s insane. This means the tip of the blade travels 772 meters in a single rotation. The speed of sound is 340 meters per second, meaning if it travels more than 0.44 rotations in a second, the tips of the blades are breaking the sound barrier.

Birds won't be happy, unfortunately. Yet, better than wrecking Earth's cycles by pumping to much garbage in the atmosphere like we do today.

Fortunately, this is an offshore turbine, so it gives a lot of surface area for marine life to live on, which eventually turns into food for birds.

Re: The world’s largest wind turbine has been switched on

#35

Post by karmakurtisaani »

windows2020 wrote: post #12

I wonder what paint job would best prevent birds from being destroyed by this. It looks like sometimes one blade is painted black for this purpose. How do bird deaths from wind turbines compare to other manmade objects?

It's offshore, so it provides surface area for marine life to live on. Fish can eat that algae, and birds can eat those fish.

Re: The world’s largest wind turbine has been switched on

#36

Post by jeffbee »

In the port of Halifax right now there are two heavy-lift semi-submersible transports carrying 12 13MW wind turbines destined for the Vineyard Wind project off Cape Cod. A photo of what the tower segments look like: https://twitter.com/BenMacLeod/status/1680629818931511296/ph...

Re: The world’s largest wind turbine has been switched on

#37

Post by twosdai »

samstave wrote: post #14
Qem wrote: post #9

Curious about what is the upper limit. How much can we go beyond 16 MW before physics laws put a cap on size?

We need to figure out how to get things to spin in space really fast - like some piezioelectrical fan blade turbine that takes advantage of the extremes in differential temps? @Twosdai - I was talking about space generators, there is no air. So how get spin, from temperature diffs that can turn a turbine/generator?

I don't think that it's necessarily speed which is the thing that we should look for. It's how best to convert large amounts of moving air into rational motion. So a large slow moving windmill may generate more power than a smaller faster moving one.

Re: The world’s largest wind turbine has been switched on

#38

Post by tda »

Qem wrote: post #9

Curious about what is the upper limit. How much can we go beyond 16 MW before physics laws put a cap on size?

Last I heard I think 25MW turbines were in some early stage of development. At least that is the biggest my former employer I recall was considering for their latest installation vessel. But I have been out of the loop for a while, so would love to hear an update.

The first 14MW was installed quite a few years ago (and it might have been upgraded to 15MW), so this is just a small-ish increase in max size. The big news, foe at least, is that it is Chinese. Siemens, Vestas and GE have some serious competition now it seems

Re: The world’s largest wind turbine has been switched on

#39

Post by walnutclosefarm »

ninkendo wrote: post #5

123 meter blades, that’s insane. This means the tip of the blade travels 772 meters in a single rotation. The speed of sound is 340 meters per second, meaning if it travels more than 0.44 rotations in a second, the tips of the blades are breaking the sound barrier.

The GE Haliade X, smaller but not by a lot, maxes out at 7 rotations per minute, giving a rotor tip velocity in the vicinity of 80m/s. Generally noise considerations mean you don't aim for a tip velocity faster than that, although for a turbine that is only installed in offshore or other uninhabited locations, you might design for a higher tip velocity. Despite some advantages to higher velocity, though, considerations related to erosion caused by high speed impact of dust, water drops and ice particles become an issue long before you'd get to supersonic speeds.

Re: The world’s largest wind turbine has been switched on

#40

Post by function_seven »

tekla wrote: post #6
timpeq wrote: post #4

"just one of these turbines should be able to produce enough electricity to power 36,000 households of three people each for one year" Does this imply that a turbine only lasts 1 year?

How does it imply that?

I think parent is pointing out the unnecessary “for one year” part. What is the purpose of that?

I assume that this turbine should be able to supply those 36,000 households for an arbitrary amount of time, not just one year.

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