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Texas power issues. Windfarms getting iced up. 67

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Well you would be laughing your heads of if I didn't. ;-)

There is a rhyme in Swedish that goes like this.
Sheep do not get sheep, sheep get lambs.
If I put it in google translate.
It looks like this.
Sheep sheep not sheep, sheep sheep lambs.
[rofl]

Sometimes I writes directly in English and sometimes I translate or both depends.

FacEngrPE I was actually starting to wonder where I got the windmill from, if it was something I invented myself.

/A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
not to worry... your English is better than my Swedish... reminds me of the muppet Swedish chef... who does't speak Swedish, but 'mock Swedish'... when asked what he really spoke, he answered 'mock Japanese'... and then went of on a Japanese tantrum...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Well here is a conspiracy theory it can be a real Swedish chief who is the inspiration his name is Lars Åke "Kuprik" Bäckman. :)

/A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
Thanks for the background...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Picture 1 there. Isn't it really a wind pump, or an aerogenerator?

In any case, using windmills to mill grain phased out quite awhile ago.
Then there's this.
You'd think they'd have worked out a standard name for them by now.

I've no idea what picture 2 is. A fancy weather vane?
 
What's the technical issues with unfreezing a gas pipeline and a gas well.

Is it just get them warm and it starts flowing again or do knock on issues rear their head?



 
One possible issue; Remote gas wells may not have electricity available for easy freeze protection heaters.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
It depends whether it has literally frozen with water, either freezing instruments or water drains or whether it has developed gas hydrates.

Hydrates you "melt" by either reducing pressure, raising temperature or injecting "anti freeze".

But then you need to do something to stop it happening again and if it's a hydrate issue that means continuous injection of MEG or methanol (horrible stuff) or somehow adding enough heat until you can remove the water.

Lots of places for the system to freeze until you get into the main transmission pipeline if you haven't allowed for it. Fix one problem and it will freeze somewhere else or your control system packs up or you haven't got electricity yourself.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
You need to be really careful melting a hydrate plug as you need to avoid the plug freeing itself and then shooting down the flowline like an artillery shell.....



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
According to the article in oilprice.com, the projected consumption was 67,000 megawatts. But the shadow estimates published by ERCOT suggested about 72,000. And that they could only cobble together about 40,000.

If they had used some type of manual (MCD) or automatic consumption disconnection (ACD) that we have here.
This would not have caused the entire electricity grid to collapse.
ACD would have disconnected all boilers and heat pumps and other large consumers not deemed necessary for short periods if the mains frequency dropped below 48.8 - 49.4 Hz.
And if this did not help to restore frequency to above 50 Hz, after 15 minutes MCD would taken place by disconnecting consumers with rotation at regional level.
You disconnect consumers for a period and then you disconnect another area and turn on the previous until electricity production is restored.
Regardless of what triggered the energy shortage, it should not have failed the entire electricity grid, if they had disconnected consumers in time.
So either they did not have a good enough crisis plan for this or something else must have had an effect as well.

Best Regards A



“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
As you point out one of the missing factors is the lack of ability to control demand. Most of the commentary has been about the failing supply (due to the cold) and the increase demand (due to the cold). But there doesn't seem to be any ability to actively manage demand. Empty office buildings lit up and presumable heated too isn't a good look!
EuUqn5CXIAA32ct_wneake.jpg


Demand management isn't easy but as you point out various countries have implemented their own approaches of ACD. Here in Australia our peak power is summer. When the grid is stress the main power management is requests by government to minimise air conditioning as well as various industry such as aluminium smelters that can at least briefly turn off their usage.
 
1503-44 Pivture 2 is from Williamsburg Virginia, has an area that was restored to the general appearance it had in the late 1600's when it was the capital of Virginia. Robertson's Windmill was once a small commercial flour mill.
I guess total power on a windy day would be less than 5 HP.
 
In some countries in Europe most of industry and large commercial properties have what's call ripple receivers on the main supply and certain sub systems.

It means the grid can shut them off from the central control room. There is protections and a levels of cut off for critical systems so the whole building doesn't go black.

They can also control all the solar grid tied inverters power factor and also there output level. And this goes down to small producer level.
 
In the article it was mentioned that In extreme situations, residential heating gets precedence over power generation which sounds nice.
As a power provider you must have if not automatik control over your transformation station at least manual, It is a must to have a power control room to managed the grid power and if you do not have the possibility to regulate and control the equipment from it, it would be quite useless.
I think they didn't have a proper crisis plan and experience to handel the situation.

Here in Sweden "Svenska Kraftnät" and and I would guess in all of Scandinavia and the Baltics as we are in the same power market "Nord Pool" they praxis different scenarios every autumn, in how to handle the variations and faults that can arise during the winter which is our high peak season.
We have never needed to use MCD, we can always buy from the outside if needed.
So if it would happen I am not shore how well it would work in practice.

I think some one sade that some large buildings hade there own power backup so it might why some houses are lite in the picture.

Here is how it looks for Scandinavia and the Baltics right now.

Elnu_psaq2n.jpg


Best regards Anna

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
Lithuania is having that fight with Belarus over that new reactor so that's doing funny things.

Plus all three Baltic states are still synced to Russia
 
Following the Northeast blackout of 1965, some system level automatic load reduction was installed in the eastern grid. (IEEE Paywall, unfortunately I was not able to find a accessible copy of this. It is probably the article I saw in the my fathers copy of the IEEE Spectrum at the time A reasonably good summary of the events described in the report.
This is one of several events that eventually lead to the creation of NERC


I have attached some PJM operator training material
here
I attached the second document, which has some rather extensive background on a number of blackouts.
A slide share presentation with more history A research paper with more power system detail on historical blackouts
It is interesting to note that in at least some of these events knock on items extended the outage. In 1965 some substations could not be restarted due power to run the station air compressors so the breakers needed to restore station power could not be operated. Similar in impact to frozen in gas wells.
 
if your interested this is what I was on about.


And in Germany at least all solar installations have to have one of these fitted so they can drop the grid injection from inverters. I think there is 0% 30%,50%,70% and 100%. They can also move the Power factor between 0.8 either way.

There is a link into KNX to deal with subsystem level isolation and to keep critical systems live. I believe also they can trigger backup generators in hospitals etc to start up and take over before the grid actually drops.

They don't have it where I am but my inverter is already setup for dynamic reactive and power level control.
 
My electric utility has installed so-called smart meters for residential customers, perhaps for commercial ones as well. The utility has a program that residential customers can opt into that allows demand management. It is usually explained in terms of setting back thermostats during the summer, typically peak usage due to AC, but I suppose it can be done any time. I think the customer gets a slightly reduce rate in return. So demand management by the utilities can be and is being done.

EDIT: Forgot to add, the customer who opts in is supplied by the utility with a thermostat that enables the demand management.

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
My heat pump also has an input for a ripple receiver as well. Which would allow the grid to change its mode. There is an emergency mode which can be triggered which sets the place to 10 degs C heating and kills active cooling.

In fact most most smart heating systems in Europe now come with it. But its only really the central European country's that have the control and transmitters up.

The commercial shut downs the customer actually get quiet a bit of compensation when it happens I believe. As do the standby generators that are triggered.
 
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