National Grid Capacity Market Notice (withdrawn) 22nd November

Saga

Can someone much more knowledgeable than me put this withdrawn CMN into some context? Are these notices completely normal in that that they are issued all the time but for the average person are of little or no consequence, or are rolling blackouts for the next six months imminent?

ariarnia

i think @[Deleted User] explained it a while back and will hopefully explain again

my probably bad remembering is the notices are normal in winter and that theres three (?) levels of 'more worrying' with this first automated level being like a warning there might be a shortage based on a computer looking at roughly expected demand and supply. but the wind might blow more or people might use less so dont worry at this level.

then the second level was there is a shortage we're going to have to buy some expensive electric from france. the lights will stay on but it'll be expensive. 

then the top level was that's not worked and businesses will be asked to cut down use or there might be blackouts

then this winter we're looking at an even worse level of that didn't work either so normal people will see blackouts  

but i'm probably completely remembering that wrong so it's not worth the electric it took me to post it

[Deleted User]

They're not a weekly occurrence, but CMNs are pretty regular - it's an automatic notification which sort of means "if nobody does anything at all, we will have slightly less spare power station space than the calculations say that we should have".  We had several in the summer and they're nothing to worry about (although I expect the usual headline writers will try to stir something up).  All that needs to happen is an operator to ask another power station to be available, or to buy a bit of power from another country, or tell a station that is due to turn off/down to not do that, and everything is fine.  That's what happened today - they found another power station willing to run if needed and that meant we had enough spares again.

Things start to get interesting when we get an EMN (Electricity Margin Notice) - which is triggered by an operator in the control room when they notice something changing that means the amount of spare power stations is less than planned and required - things like a station breaking down or the weather forecast being massively wrong.  It still doesn't mean that we don't have enough generators, just that we don't have all the planned amount of spares.  Again, fixed by the same things as above, but tends to be seen nearer the time so has a little more urgency (and some stations can't get ready fast enough to help).

If we get to HRDR (High Risk of Demand Response/Control), this means that we've run out of things to do on the generation side and still haven't completely fixed the problem - so we might have to start on the demand side of the balance if things get any worse.

DCI (Demand Control Imminent) means pretty much what it says - the "High Risk" from the previous warning has happened and we're about to start some of the emergency control measures.

Even DCI doesn't mean that there are going to be power cuts.  There are customers with interruptible contracts that will turn themselves off first, and the networks can do things like voltage reduction to reduce the demand further.  Anyone with a backup generator will be asked to go onto their generator and disconnect from the grid.  There are even the facilities to plug diesel-electric locomotives into the National Grid as emergency generators (we can jump-start some of our power stations from trains!).  Only if all of those measures fail will there be unscheduled interruptions to the general public supply

Spoonie_Turtle

[Deleted User] said:

There are even the facilities to plug diesel-electric locomotives into the National Grid as emergency generators (we can jump-start some of our power stations from trains!).

Always knew trains were awesome, but I didn't know *that*!  Very cool.

doodling

Hi,

It is probably worth looking at the NG ESO "Order of Action for Winter 2022" which details the order in which the ESO will carry out actions to maintain supply.  Try: https://www.nationalgrideso.com/document/268116/download

Deleted_User said:

[...]

There are even the facilities to plug diesel-electric locomotives into the National Grid as emergency generators (we can jump-start some of our power stations from trains!).

[...]

I'm pretty sure that there aren't. The average diesel locomotive at 2.5MW isn’t going to make much of a dent in the start up requirements for anything big in any event.

I've only ever seen locomotives used in the event of alternator exciter failure in the 70s / 80s.  (For example see  http://www.class47.co.uk/c47_zoom_v2.php?img=0822050000210 - I'm particularly impressed with the massively oversized bushing (edit: that appears to be, maybe an artifact of the camera angle?) on the loco roof).  Was there something else you are thinking about?

[Deleted User]

doodling said:

Hi,

It is probably worth looking at the NG ESO "Order of Action for Winter 2022" which details the order in which the ESO will carry out actions to maintain supply.  Try: https://www.nationalgrideso.com/document/268116/download

Deleted_User said:

[...]

There are even the facilities to plug diesel-electric locomotives into the National Grid as emergency generators (we can jump-start some of our power stations from trains!).

[...]

I'm pretty sure that there aren't. The average diesel locomotive at 2.5MW isn’t going to make much of a dent in the start up requirements for anything big in any event.

I've only ever seen locomotives used in the event of alternator exciter failure in the 70s / 80s.  (For example see  http://www.class47.co.uk/c47_zoom_v2.php?img=0822050000210 - I'm particularly impressed with the massively oversized bushing (edit: that appears to be, maybe an artifact of the camera angle?) on the loco roof).  Was there something else you are thinking about?

Yes.  One alternative black-start procedure for Ratcliffe-on-Soar (which I have been involved with) was to use a loco to jump the local OCGTs, which could then provide the auxiliary power to start one of the coal units, which itself then has enough power to start the other three units.

Never expected to be used, as the OCGTs should be able to start themselves, but was still an option.

That order of action document is a nicely laid out summary actually - will be stealing that link!

macman

How do you get the diesel-electrics to the power stations if it's a train strike day? 

brewerdave

Don't tell Mick Lynch - he'll use it as a negotiating tactic !!

Grizzlebeard

macman said:

How do you get the diesel-electrics to the power stations if it's a train strike day? 

You don't!

Very long extension leads and a non-union (private sector) security guard with a spare diesel train key.

QrizB

doodling said:

I've only ever seen locomotives used in the event of alternator exciter failure in the 70s / 80s.  (For example see  http://www.class47.co.uk/c47_zoom_v2.php?img=0822050000210 - I'm particularly impressed with the massively oversized bushing (edit: that appears to be, maybe an artifact of the camera angle?) on the loco roof).  Was there something else you are thinking about?

I remember reading that used a diesel loco for power in Canada in 1998:

https://www.thedrive.com/news/39378/how-canadians-derailed-a-train-and-drove-it-to-city-hall-for-power-after-a-brutal-ice-storm
https://gizmodo.com/that-time-a-canadian-town-derailed-a-diesel-train-and-d-1846307148