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What Happened in the UK Blackouts?

mitchoneill.com

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Re: What Happened in the UK Blackouts?

#101

Post by _def »

std_throwaway wrote: post #63
londons_explore wrote: post #16

It's notable that this report is completely consistent so far with the way I would design a cyber attack to take out a countries power grid. > The causes provided by RWE for the initiation of the trip of Little Barford steam turbine (ST1C) was due to discrepancies on three independent safety critical speed measurement signals to the generator control system. A cyber attack would most likely, rather than directly take…

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…

Reminds me of stuxnet

Re: What Happened in the UK Blackouts?

#102

Post by Iwan-Zotow »

circular_logic wrote: post #62
eDISCO wrote: post #10

Most traditional generators (think CCGT, nuclear, hydro) run in synchronous mode. Which means the generators spins with rpm proportional/equal to the network frequency. For 50Hz that would be 3000rpm. When the total electricity demand exceeds the supply, the kinetic energy of spinning generators is converted to electricity which slows down the generator rpm, which reduces the frequency. All synchronous generators on…

That makes me wonder, if you were standing next to these turbines would you be able to here them slow down?

Yes

Re: What Happened in the UK Blackouts?

#103

Post by jacques_chester »

wongarsu wrote: post #64
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!

Pretty much the only plants you can get to full power in such a short notice are battery or hydroelectric. Even pumped-storage hydro typically takes 10-30 seconds to full power because of inertia. Batteries are much more expensive, but as close to instant as it gets.

Other fast responders are supercapacitors, superconductor magnetic energy storage, flywheels, compressed air and there probably a lot more I don't know about.

What conventional chemical batteries have is mostly that they are manufactured in vast quantities, so the unit costs are constantly improving.

Re: What Happened in the UK Blackouts?

#105

Post by jacques_chester »

the_mitsuhiko wrote: post #99
rcxdude wrote: post #61

Earlier quoted context omitted.

The grid frequency itself doesn't matter much as far as consumers are concerned, the deviations mentioned in this article would not cause any problems for a home user directly (or even generators, but as mentioned below if it is too far out of range generators start to need to cut out) but it is a far better indicator of the general balance of supply and demand of power in the grid than any other metric, because it c…

> The grid frequency itself doesn't matter much as far as consumers are concerned So I thought and then we had a multi week frequency shift in the EU and various clocks started lagging behind. This does show up for consumers as well.

Generally grids try to average out to their target frequency over some period (24hrs, for example) because so many timekeeping systems rely on counting cycles.

So sometimes they will run slightly above target and sometimes they will let it run slightly below target. Ordinary daily demand cycles help.

Re: What Happened in the UK Blackouts?

#106

Post by londons_explore »

slovenlyrobot wrote: post #83
londons_explore wrote: post #16

It's notable that this report is completely consistent so far with the way I would design a cyber attack to take out a countries power grid. > The causes provided by RWE for the initiation of the trip of Little Barford steam turbine (ST1C) was due to discrepancies on three independent safety critical speed measurement signals to the generator control system. A cyber attack would most likely, rather than directly take…

Does that complete consistency include simulating a lightning strike to a transmission line?

That happens on a regular basis anyway. Probably wouldn't have to wait more than a week for it to happen naturally.

Re: What Happened in the UK Blackouts?

#107

Post by beamatronic »

std_throwaway wrote: post #63
londons_explore wrote: post #16

It's notable that this report is completely consistent so far with the way I would design a cyber attack to take out a countries power grid. > The causes provided by RWE for the initiation of the trip of Little Barford steam turbine (ST1C) was due to discrepancies on three independent safety critical speed measurement signals to the generator control system. A cyber attack would most likely, rather than directly take…

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.

Re: What Happened in the UK Blackouts?

#108

Post by aidos »

KyleJ61782 wrote: post #76
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…

This. Very much this. In the presentations I've seen on the matter, the most vulnerable systems are those measuring and carrying telemetry back from various meters around the power system. One doesn't have to directly compromise the system to have an effect. Simply providing bad data to automated protection systems could be enough to cause instability.

A lesson Knight Capital learnt the hard way.

https://en.m.wikipedia.org/wiki/Knight_Capital_Group

Re: What Happened in the UK Blackouts?

#109

Post by mytailorisrich »

KyleJ61782 wrote: post #78
mytailorisrich wrote: post #48

Earlier quoted context omitted.

You protest a bit too much at this point, methinks. I am commenting that the scale of the disruption resulting from (only) a 5% drop does not seem reasonable and that some of the issues should have been better handled or avoided altogether. > But I and I'm sure many others would not be focusing upon that, though I can appreciate that mentality due to the way media/tabloids cover such and all issues in life That's a p…

> > But I and I'm sure many others would not be focusing upon that, though I can appreciate that mentality due to the way media/tabloids cover such and all issues in life > That's a personal attack quite out of order. Not really. It's just a societal commentary on how we've conditioned ourselves by the media we consume into passing quick blame instead of taking a slow, reasoned approach to analyzing the event, seeing…

It is a personal attack and it is not what I have written so also misrepresent my comments.

Neither of which are acceptable.

> seeing the compounding factors at stake and only in the face of gross negligence assigning blame.

You are entitled to have your views. Claiming that there is no blame to assign until it reaches criminal liability is rather odd, though.

Re: What Happened in the UK Blackouts?

#110

Post by mytailorisrich »

mellosouls wrote: post #96
mytailorisrich wrote: post #14

Earlier quoted context omitted.

I did mention the railways and indeed the importance of making sure the whole system can cope, which means what you list in addition to the grid in isolation. > None of these seem like "bad management" They do seem like bad management because to me it looks like these issues were not taken seriously. > problems of the sort you're likely to run into if you have to activate an emergency procedure you haven't needed to…

Reading this exchange as a third party, both sides make fair points, but one side is being excessively downvoted, which is either unfortunate or possibly a regrettable sign of emotional over intellectual engagement in the discussion somewhere.

It is rather odd, indeed, but usual. Their often seems to be an "incorrect" opinion.

It seems that one of the commenters work for the National Grid or related so might be a bit partial...

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