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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

#121

Post by mcronce »

antisthenes wrote: post #49
walnutclosefarm wrote: post #39

Earlier quoted context omitted.

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, consideratio…

> The GE Haliade X, smaller but not by a lot, maxes out at 7 rotations per second I think you meant per minute. Per second would mean that the rotor tips are travelling faster than SR-71.

Although I'm glad it's not reality, the imagery of a massive wind turbine whizzing around at 420 RPM is pretty amusing

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

#122

Post by chaps »

askvictor wrote: post #104
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.

Given that the wind is pushing it, wouldn't the blade tip's speed somehow be naturally limited by the wind speed?

Not necessarily!

https://www.youtube.com/watch?v=yCsgoLc_fzI

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

#123

Post by dirtyid »

doodlebugging wrote: post #90
thefurdrake wrote: post #85

Earlier quoted context omitted.

... But how many missiles would be used to take down a massive wind farm vs taking down a single nuclear reactor? Regardless of whether the enemy has lots more missiles, they still have a finite number of them. Those missiles cost money. War is as economic as it is kinetic. Using those missiles to disable power generation means they can't be used on other targets. Overuse of ammunition eats into stockpiles or forces…

Very valid points. Those who have to conduct the war must consider these things - supply chain issues, production bottlenecks, existing stockpiles - and prioritize targets accordingly. Choosing between potentially causing a nuclear disaster and disabling power generation from cleaner sources is a no-brainer for me. I'd leave the reactor intact and re-evaluate the sensibility of that decision daily in case something c…

With respect to potential TW conflict the TLDR is PRCs ongoing massive distributed renewable rollout at PRC scale is very much part of strategic energy security in event of war.

Issue in TW conflict limited to TW and PRC is scale of asymnetry too large and growing - TW unable to stockpile enough survivable fire power to meaningfully degrade PRC energy production let alone long term, especially massive PRC MIC located inland. PRCs tangible advantage is her industrial base too large to be disrupted at scale and for long. For reference medium term nuclear as % of energy mix will go from 5% to 10% (2035) which is enough to ration around during war. Long term 2050+ still "only" 20-25%. Consider scale of PRC's current distributed renewable rollout efforts is enough to power all residential use this year and likely substantial % of industrial use in coming years. Hence PRC coastal nuclear still most enticing targets even if that's warcrime territory (queue blowing up 3 gorges meme). Ultimately if TW tried to hit PRC nuclear they better commit to massive preemptive strike on reactors with their entire inventory since substations/transformers (which PRC makes indigenously) can be rapidly replaced. There's no opportunity for TW to reevaluate since PRC has stockpiles to disrupt TW completely and prevent followup strikes in retaliation and TW can't be meaningfully resupplied let alone reconstruct under motivated PRC attack. And if PRC preempts, TW options even more limited. It's a matter of who can rebuild infra and out attrite, which overwhelmingly favours PRC. WW2 strategic bombing worked for US because adversaries couldnt disrupt CONUS logistics. Even that is increasingly challenged if US commits to total war with PRC in TW scenario since PRC is boostering global strike capabilities which will hopefully limit scope of war due to mutual homefront vunerability (between PRC and US at least).

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

#124

Post by squarefoot »

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.

Birds are a lot less happy about mirror glass buildings; in some places it literally rains dead birds.

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

#125

Post by creatonez »

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.

Just to examine the common claim about wind turbines killing birds -- the number of birds killed by wind turbines is vanishingly small compared to other threats.

https://www.fws.gov/library/collections/threats-birds

234,012 - Collisions: Land-based wind turbines

6,600,000 - Collisions: Communication towers

72,000,000 - Pesticides & other poisons

214,500,000 - Collision: Vehicles

599,000,000 - Collision: Glass skyscrapers

2,400,000,000 - Predation by cats

[Unknown] - Habitat loss and climate change

These are just some estimates of some admittedly very difficult to capture data, but the orders of magnitude differences are revealing nonetheless.

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

#126

Post by djbusby »

dylan604 wrote: post #97
civilitty wrote: post #24

Earlier quoted context omitted.

We just need to hook it up to a flux capacitor and the next typhoon will give us time travel.

I did the math, but we didn't hit 1.21 jigawatts

Back in the day, it was still spelled Giga but pronounced Jiga. I heard from some old-heads at power company.

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

#127

Post by nerdbert »

windows2020 wrote: post #61
throwbadubadu wrote: post #25

Earlier quoted context omitted.

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?

If wind turbines were the number one bird killer, wouldn't figuring out the best color to paint the blades or other mitigation strategies be worth it?

They're not even the number ten bird killer.

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

#128

Post by gnatman »

rcme wrote: post #8
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.

That is crazy, but, on the other hand, seeing this rotate faster than once every two seconds would be insanely fast.

Here's turbine in Denmark that lost its brakes and disintegrated in 2008. The description says the tower was 60m tall.

https://www.youtube.com/watch?v=7nSB1SdVHqQ

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

#129

Post by mcpackieh »

jameskerr wrote: post #44

Giant turbines out in the ocean with regular gales and storms. That must be a massive challenge to construct.

Probably not so bad compared to the construction of the Bell Rock Lighthouse.

https://en.wikipedia.org/wiki/Bell_Rock_Lighthouse#Construct...

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

#130

Post by wffurr »

adgjlsfhk1 wrote: post #113
jakewins wrote: post #109

Earlier quoted context omitted.

At least in sailing, you can go a lot faster than the wind; I assume the same is true for these blades.

it would be except that the goal of a wind turbine is to generate power rather than go fast

How do you go fast except by generating power? Force times distance over time, that’s how sailboats move too.
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