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The world’s largest wind turbine has been switched on

iflscience.com

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

#161

Post by thebruce87m »

SoftTalker wrote: post #136
themitigating wrote: post #133

Earlier quoted context omitted.

You'd think there would be a backup brake kit on these

I thought they would feather the turbine blades so that they didn't generate rotation. Maybe that failed as well?

On the smaller turbines I worked on, the speed of rotation was controlled by feathering the blades as you’d expect. Braking was also achieved the same way, with the friction brake acting as a “handbrake” once the blades were slow enough.

One thing that some people don’t consider is that the direction the turbine faces is also controllable and therefore used for braking. A lot of people think the turbine is blown by the wind to face the correct direction, but there is a separate wind direction sensor and a motor to turn the turbine.

The friction brake could be applied at speed, but that was for emergencies.

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

#162

Post by LorenzoGood »

flangola7 wrote: post #159
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.

How can you travel faster than the wind that is pushing you?

Apparent wind, and angle

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

#163

Post by rrrrrrrrrrrryan »

mx_02 wrote: post #116

Is bigger better when it comes to wind power?

Yes, for two reasons: windspeed is greater at higher altitudes, and energy capture increases with the square of the blade length:

https://www.gwec.net/wp-content/uploads/2017/01/Netherlands_...

This means that a windmill constructed with 3x the building material (3x blade diameter and 3x taller) will generate over 9x the power.

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

#164

Post by adrianN »

landemva wrote: post #157
adrianN wrote: post #144

Earlier quoted context omitted.

Energy consumption is a bad indicator of living standards. Everything that defines my living standard has become much more energy efficient during my lifetime. I have for example more light in my house than I used to and consume about 20% of the energy I used to. My induction stove uses a lot less energy than the wood fired stove my grandma had at her house. My current computer uses about a tenth of the electricity o…

Induction stove. Electric car. Heat pump. Those are indicators of being born in privilege. What about your AC in car and hotel and home? USA setting off nukes and Britain fire bombing Dresden are examples of energy use which is wasteful and polluting. There are always exceptions to one broad indicator, in this example energy usage. Technology improvement typically brings more efficient use of resources and less pollu…

My point is that maximizing energy demand in no way leads to improved living conditions.

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

#165

Post by appplication »

kitd wrote: post #145
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.

I don't know about this one, but a single rotation of the turbines recently installed in the North Sea can generate enough electricity to power an average family home for a day.

Wow that is a really interesting and coherent way to conceptualize how much power it makes, and how quickly.

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

#166

Post by hamilyon2 »

pkulak wrote: post #131

> just one of these turbines should be able to produce enough electricity to power 36,000 households of three people each for one year What is the point of adding a time component in there? They always say weird things like this that make me double take. "Wait... does one revolution power 36,000 homes for a YEAR???" What's really annoying is that they aren't even wrong, just annoying.

Confusing power and energy units seems to be a constant theme not only in reputable press, but in a lot of publications that consider energy, infographics and so on. There are also instances of correct, but confusing units, like KW/h per year when talking about power.

I don't understand it and probably never will. I think at this time readers in much of english-speaking world expect this type of errors and will mind the "correct" language, e.g. simply watts when talking about power.

I think there is a joke somewhere here about all power stations stop working exactly after one year of coming online because of people unable to imagine amount of fuel per unit of time.

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

#167

Post by Animats »

petee wrote: post #91
Animats wrote: post #46

The picture looks strange. You can see a ship through the turbine blade. That seems to be because ifisicence took a promotional picture with lettering and leaf decoration from here [1] and "cleaned it up" with some photo tool. General Electric and Vestas both have 14 megawatt wind turbine prototypes in operation. This seems to be a prototype deployed in a large installation. It's not in the catalog yet.[2] Mingyang h…

It is an unedited photo, available in their press packet -- http://www.myse.com.cn/en/zlxz/index.aspx

You're right. That's clearer in the high-rez version. It's a wind turbine in the fully feathered shutdown condition, with the thin edge of the blades facing forward. So the blade looks thin.

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

#168

Post by jameskerr »

mcpackieh wrote: post #129
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...

Wow, brutal! “And all the stones carried by one horse, Bassey.”

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

#169

Post by landemva »

adrianN wrote: post #164
landemva wrote: post #157

Earlier quoted context omitted.

Induction stove. Electric car. Heat pump. Those are indicators of being born in privilege. What about your AC in car and hotel and home? USA setting off nukes and Britain fire bombing Dresden are examples of energy use which is wasteful and polluting. There are always exceptions to one broad indicator, in this example energy usage. Technology improvement typically brings more efficient use of resources and less pollu…

My point is that maximizing energy demand in no way leads to improved living conditions.

Can we agree that energy released and used in war fighting is wasteful? In the general view of war fighting "over there". Britain did not improve the living conditions of those in Dresden.

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

#170

Post by landemva »

Gwypaas wrote: post #158
landemva wrote: post #157

Earlier quoted context omitted.

Induction stove. Electric car. Heat pump. Those are indicators of being born in privilege. What about your AC in car and hotel and home? USA setting off nukes and Britain fire bombing Dresden are examples of energy use which is wasteful and polluting. There are always exceptions to one broad indicator, in this example energy usage. Technology improvement typically brings more efficient use of resources and less pollu…

Many advanced economies have decoupled energy use from economic growth. https://ourworldindata.org/energy-gdp-decoupling

USA, and some western Europe, exported dirty manufacturing energy use and pollution outside the borders. Any nation rich or strong enough to export pollution of manufacturing will tend to show the numbers you highlight.
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