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Electrical outages. cyber attacks ?

aligarjon
What's the chances of the power outages and airport problems being cyber attacks.     Is that possible.   I would think so  ?


Gary

  • 0
    I suspect it isn't as simple as Broadgage reports since the need for load shedding isn't just based on load / frequency issues. Transmission line outages can mean load shedding is needed when the generation is adequate.
  • Former Community Member
    0 Former Community Member

    broadgage:

    As has been reported, DNOs automatically disconnected about 5% of the load due to the falling frequency.

    When this next happens, will the SAME 5% be disconnected or does some means exist to spread the pain and disconnect a DIFFERENT 5% next time.



    Lessons will be learned, Broadgage - there won't be a next time, someone* has waved their hands about and proclaimed "Make it so" 


    Regards


    OMS

    * - there will be a variety of someones depending on circumstances

  • 0
    What goes around,comes around.


    Looking through my archive I came across this.


    Sunday morning, just before half past eleven.

    11.24 A switching incident at Battersea disconnects the 70 MW generator in service; almost simultaneously a generating unit at Deptford sustains serious damage.  Immediately a second unit at Deptford trips out as a result.

    11.26  The third remaining unit at Deptford trips out.  Both stations disconnect from the grid and the load is picked up by other stations, some as far away as Brighton.  Within the next four minutes the load on the single 132 kV line across the Thames is trebled.

    11.30  That 132kV line trips out.  The automatic protection on the power plants at Barking operates and by 11.40 that station is disconnected from the grid.  Woolwich also shuts down.

    11.40 Brimsdown "B", Hackney, Walthamstow and West Ham disconnect from the grid.

    11.45  Bankside, Croydon and Norwich disconnect from the grid.

    Stations as far away as Brighton disconnect.


    Most supplies were restored very quickly, but some took up to four hours to restore, including the Southern Railway which was cut off until 3 o'clock in the afternoon.


    The station names show that this was some time ago.  The date?  29th July 1934, not long after the grid became operational.


    David
  • 0

    OMS:




    broadgage:

    As has been reported, DNOs automatically disconnected about 5% of the load due to the falling frequency.

    When this next happens, will the SAME 5% be disconnected or does some means exist to spread the pain and disconnect a DIFFERENT 5% next time.



    Lessons will be learned, Broadgage - there won't be a next time, someone* has waved their hands about and proclaimed "Make it so. 


    It is still likely to be 5%, but it shouldn’t include critical infrastructure in the first tranche. In the end of the day, without more inertia, and the nuclear stations being planned will create some additional inertia, the frequency falls off rather rapidly. The incident was interesting, because of the speed of the fall. Normally, voltage reduction would come first, followed by rapid support from pumped storage, however, there didn’t seem to be time for that without automatic demand reduction. 


    In in the end of the day, recovering from 5% is a lot easier than recovering from 100%. We have done both in the past, albeit not for many years. Even 100% demand reduction, where the transmission grid remains live is preferable to a true black start scenario. 


    We also need to remember that there were trains stuck round the place blocking tracks, where the driver did not have the authority to implement a restart once the traction supply had returned. Allegedly, the restore had to be carried out by a technician, who first had to locate, and travel to the train. There were many lessons to be learned in my opinion, including the accuracy of the press reporting, which seemed a little sensational and over-dramatic, attempting to make a good story. Out of curiosity, did anyone see Sunday’s press release from Ipswich hospital which put the blame for their supply failure (which affected outpatients and x-ray only) on a circuit breaker that did not close to put that area onto the working generators that were already supplying the rest of the hospital. 


    Regards,


    Alan. 

  • 0
    It strikes me that as we move away from inertial loads that care about frequency, but can also act as generation for a short period, we probably also need to move to non -inertial generation, where in any case frequency does not change as voltage falls, or if it does, this  it is only because the electronics has been very deliberately programmed to emulate a mechanical system

    In the mean time we probably need to ask if we ought to accept wider frequency variations before making the disconnect decision, and what the impact would be..
  • 0
    Yes, but you have to remember that there is still a lot optimised for 50 Hz, from older passenger lefts, through to the humble clock-radio, where the 50Hz signal is still used for the derivation of the “seconds” count. In fact, that is why you will often see prolonged frequency measurements above 50Hz, as there is a statutory obligation to keep the time correct over a 24 hour period. 


    The other her issue regarding inverter drives for generation, is that there is not as much fault current available compared to a large mechanical set, say a 500MW generator for example. This, ultimately will affect close on 100 years of power system protection theory, overload characteristics, and grading. A lower inertia grid is coming, and the supply industry will adapt, but where the reliance was the inertia inherent in a large generating station, demand reduction is more likely with low inertia, simply because nothing else is fast enough to respond. Even Dinorwig pumped storage is relatively slow now for a low inertia system. The turbines usually spin in air at synchronous speed, and it can ramp from zero to 1800MW in about 16 seconds from pressing the start button. When the upper lake is full, it can run for about six hours before running short of water. 


    Regards,


    Alan.
  • 0
    It seems to me that a lot of people are looking for ways to patch up a system which is fundamentally flawed in its expectations. If one wants power from wind then surely the wind provider must arrange that it is compatible with the rest of the grid? If this means that he must provide a big battery, or standby generation or anything else as his power is not constant with a reasonable time consistancy, he must take that as part of the cost of providing his power source. The idea that someone else pays for his failure to provide a contracted power level, and that he may change it on a cycle by cycle basis is ridiculous in the extreme. Clearly the contracts for wind were written by people who were more interested in virtue signalling (look how much renewables we have...) rather than a solid engineering proposition which we then require friom everyone else! The result is that we now have an unreliable power system which is disasterous for the economy. As for trains which cannot be started by the driver, the world is now even madder than I thought! Austrailia and the Germans are not too happy with theirs either, but problems are little reported because it damages the virtue cause. Spinning reserve is now tiny because no one will pay for it, and it is constantly critisised because it is using fossil fuel. The need for reserve is greater than ever because of renewables which cannot be faulted whatever havoc they cause. Wonderful.
  • 0
    Yes, but defending wind generation to some extent (and I don’t often say that), the reason for the wind farm disconnecting from the grid is not yet in the public domain. The only report in the public domain, is that it didn’t disconnect through lack of wind. 


    Regards,


    Alan.
  • 0
    That lack of comment is strange in itself. It appears that the report is top secret, and quite possibly is political dynamite. I'll have to wait and see. However fundamentally my remarks are reasonable even if the cause was not "wind trouble" although the weather was certainly not good for wind turbines.
  • 0
    I agree with your remarks, however wind strength does not seem to have been the issue on this occasion. Incidentally, I haven’t seen the Ipswich hospital press release that I referred to earlier in the media. It can be found here: https://www.esneft.nhs.uk/major-power-cut-across-parts-of-england-and-wales/. Also of interest, the Financial Times seems to suggest they know what is in the report that Ofgem now have. They propose that the wind farm went first for “technical issues that have now been resolved”. The story can be found here: https://www.ft.com/content/8b738eac-c024-11e9-89e2-41e555e96722


    Regards,


    Alan.

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