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What Happened in the UK Blackouts?

mitchoneill.com

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Re: What Happened in the UK Blackouts?

#131

Post by jhayward »

barney54 wrote: post #73
guerby wrote: post #47

Earlier quoted context omitted.

I assume battery based grid power stations like the Tesla one in Australia are amongst the best in class to help in this kind of crisis situation? Compared to the gaz turbine the system it is simpler (no mehanical/heat/fluid parts) and depending on design will likely never be completely off since made of dozens or hundreds of independant equipement (batteries and inverters). Thanks for the article and comment!

Yes, batteries are very fast acting, but that battery in South Australia is only 100MW and the grid lost over 1400 MW. https://www.news.com.au/technology/innovation/inventions/eve... Batteries have a lot of potential, but they are currently small in capacity.

> but that battery in South Australia is only 100MW and the grid lost over 1400 MW

I hear this kind of misconception fairly often and so it is worth noting that you don't need 1400 MW of battery to protect from this event.

The initial 735 MW drop happened, as I read TFA, when a major generating source took itself offline as a result of the frequency disturbance. The later generator drops are cascades of the frequency disturbance earlier in time.

If a suitable battery had been present and reacting in milliseconds it could have stabilized the frequency enough, for just the very short period required, to avoid the whole generator trip in the first place. Thus you can use much smaller amounts of fast-response frequency support to avoid much bigger drops. This is how batteries can pay for themselves so quickly when placed in the right topologies w.r.t to the grid demand and generation resources.

Re: What Happened in the UK Blackouts?

#132

Post by mytailorisrich »

sergioj97 wrote: post #65
Zenst wrote: post #42

Earlier quoted context omitted.

"Would you not prioritise an airport, a hospital, the railway, over residential areas?" Yes and they do. As mentioned, things get added to the grid all the time, case of the airport was that it was not on a priority list. Yes that is an oversight, but who's fault and accountability we do not know. The onus would of been in the airport to inform the power distribution and if that failed to happen then the airport woul…

I'm pretty sure there is a lot of people who is interested to know if this is someone's fault, and I don't think it has anything to do with how media covers this issues. I think it's a good thing, in fact. This failure may be within acceptable parameters and it may be simply meaningless to try to find someone truly responsible for it. But you seem to be unreasonably reluctant to believe that maybe it's not. I underst…

> But you seem to be unreasonably reluctant to believe that maybe it's not

He seems to be working for National Grid or at least in the field so might be defending his own here or taking my comments personally.

Re: What Happened in the UK Blackouts?

#133

Post by philjohn »

computator wrote: post #128

Simplifying, this is what I get: (1) A lightning strike creates a transient voltage on the grid. (2) Some power generators remove themselves from the grid to prevent damage to themselves from the transient voltage. (3) Now there is too much demand on the grid -- too many people using power and not enough generators to supply it. (The line frequency dropping indicates that supply and demand are not balanced.) (4) So t…

4 needs to happen, and is the benefit the UK has of a massive country-wide electricity grid. As someone else said, cascading failures and a much worse time.

Re: What Happened in the UK Blackouts?

#134

Post by justapassenger »

beamatronic wrote: post #107
std_throwaway wrote: post #63

Earlier quoted context omitted.

An even more stealth method is to make the system work perfectly if everything is running fine. Like correctly reporting net frequency in the range 49-51 Hz but reporting false values when outside of that range. That way there will be no detectable errors until everything starts behaving erratically. The best way for a society to prepare is to have a few small incidents that put the safety systems to the test on a re…

Well, that and decentralizing your power infrastructure.

Decentralized grid will have less ability to deal with spikes in load, and be more unstable as a result. Question in cases like this is often - do you want to have a lot of smaller outages all the time or bigger, but less common outages.

Re: What Happened in the UK Blackouts?

#135

Post by DanBC »

mytailorisrich wrote: post #132
sergioj97 wrote: post #65

Earlier quoted context omitted.

I'm pretty sure there is a lot of people who is interested to know if this is someone's fault, and I don't think it has anything to do with how media covers this issues. I think it's a good thing, in fact. This failure may be within acceptable parameters and it may be simply meaningless to try to find someone truly responsible for it. But you seem to be unreasonably reluctant to believe that maybe it's not. I underst…

> But you seem to be unreasonably reluctant to believe that maybe it's not He seems to be working for National Grid or at least in the field so might be defending his own here or taking my comments personally.

Several people in this thread have said that you are wrong to place blame entirely on the grid. It's unlikely that they all work for power distribution companies.

Re: What Happened in the UK Blackouts?

#136

Post by [deleted] »

Reason077 wrote: post #120
std_throwaway wrote: post #63

Earlier quoted context omitted.

An even more stealth method is to make the system work perfectly if everything is running fine. Like correctly reporting net frequency in the range 49-51 Hz but reporting false values when outside of that range. That way there will be no detectable errors until everything starts behaving erratically. The best way for a society to prepare is to have a few small incidents that put the safety systems to the test on a re…

”Like correctly reporting net frequency in the range 49-51 Hz but reporting false values when outside of that range.” You can’t fake the system frequency like that. Anyone connected to the grid can observe/measure the system frequency trivially - you could do so right now at the nearest 10A socket. The attack you describe would require compromising large numbers of diverse, distributed generation and frequency respon…

[deleted]

Re: What Happened in the UK Blackouts?

#137

Post by [deleted] »

delfinom wrote: post #123
Reason077 wrote: post #120

Earlier quoted context omitted.

”Like correctly reporting net frequency in the range 49-51 Hz but reporting false values when outside of that range.” You can’t fake the system frequency like that. Anyone connected to the grid can observe/measure the system frequency trivially - you could do so right now at the nearest 10A socket. The attack you describe would require compromising large numbers of diverse, distributed generation and frequency respon…

Yep. Once one meter starts reporting the wrong frequency vs the thousands of other ones. It'll simply be taken offline and replaced because it could just be a broken one. Depending on severity, the gig could be up if the meter is sent back to the manufacturer for "repair".

[deleted]

Re: What Happened in the UK Blackouts?

#138

Post by rossdavidh »

aurbano wrote: post #41

It actually sounds like this was really useful though, as a lot of the systems involved will be improved in the future. I'm not sure if the grid is already doing this, but they should trigger failures randomly, including Low Frequency Demand Disconnection schemes from time to time to ensure that all downstream systems are also ready (like the hospital someone mentioned that had an issue with the backup generator, or…

You would be setting up a Chaos Monkey (https://en.wikipedia.org/wiki/Chaos_engineering#Chaos_Monkey) on your electrical grid. The problem is, while these kinds of things are an awesomely good idea early in a system's life, they are very difficult to put in after it has become both complex and mission-critical.

Re: What Happened in the UK Blackouts?

#139

Post by mytailorisrich »

DanBC wrote: post #135
mytailorisrich wrote: post #132

Earlier quoted context omitted.

> But you seem to be unreasonably reluctant to believe that maybe it's not He seems to be working for National Grid or at least in the field so might be defending his own here or taking my comments personally.

Several people in this thread have said that you are wrong to place blame entirely on the grid. It's unlikely that they all work for power distribution companies.

I have never placed blame entirely on the grid... Can we not lower ourselves into this sort of sordid methods of trying to put words into others' mouths?
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