Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings

While ecos and wind farm proponents tried to blame the blackout on downed powerlines, a detailed report from AEMO shows it was actually wind farms that were the cause.

downed-pylons

Electricity pylons near Melrose in South Australia’s Mid North were toppled in the storm Source: ABC News Australia

From the Institute of Public Affairs | Australia’s leading free market think tank

5 October 2016 PRELIMINARY AEMO SOUTH AUSTRALIAN BLACKOUT REPORT: WIND RESPONSIBLE

The Australian Energy Market Operator’s preliminary report into the recent South Australian blackout reveals that the primary reason for the total loss of power was a sudden reduction in wind power being fed into the electricity network, according to free market think tank the Institute of Public Affairs.

“The Preliminary Report makes it clear that while the weather was responsible for multiple transmission system faults, the blackout did not occur until after the sudden loss of 315 megawatts of wind output at six separate sites over a six second period,”

said Director of Research Brett Hogan.

“The South Australian Government and the renewables industry can no longer credibly argue that the reasons for the fault relied solely on the weather. Images of downed pylons do not tell the whole story.” “In simple terms, the wind increased and some transmission lines went down but electricity generation continued. It was only the as-yet-unexplained reduction in wind farm output which overloaded demand on the interconnector with Victoria, causing the whole network to seize up.”

“Gas generation continued through the storm and the transmission line faults as did supply from the interconnector. Importantly, it was also the Torrens Island gas-fired Power Station that was used to re-start the electricity network later that evening.”

“When you rely on the weather to generate electricity, and the weather turns bad, then you shouldn’t be surprised when your electricity system in turn cannot cope.” “While renewables may very well have a place in our future energy needs, their uncontrolled rollout, powered by federal and state government subsidies is starting to do Australia damage.”

“Demand-limiting kill switches and blackouts are symbols of policy failure. It is not the role of government to favour one energy technology or provider over another. Government should be encouraging competition in a free and open market so that technology and the private sector are free to work out the best energy sources.”

“Generation initially rode through the faults, but at 16:18, following an extensive number of faults in a short period, 315MW of wind generation disconnected (one group at 16:18:09, a second group at 16:18:15), also affecting the region north of Adelaide.” Source: AEMO Preliminary Report – Black System Event in South Australia on 28 September 2016 p.2

A copy of the Preliminary Report is available here.


From that report:

Event

The predicted weather front moved through SA on the afternoon of Wednesday 28 September 2016, including high winds, thunderstorms, lightning strikes, hail, and heavy rainfall.

The weather resulted in multiple transmission system faults. In the short time between 16:16 and 16:18, system faults included the loss of three major 275 kV transmission lines north of Adelaide. Generation initially rode through the faults, but at 16:18, following an extensive number of faults in a short period, 315 MW of wind generation disconnected (one group at 16:18:09, a second group at 16:18:15), also affecting the region north of Adelaide.

The uncontrolled reduction in generation resulted in increased flow on the main Victorian interconnector (Heywood) to make up the deficit. This resulted in the Heywood Interconnector overloading. To avoid damage to the interconnector, the automatic-protection mechanism activated, tripping the interconnector. In this event, this resulted in the remaining customer load and electricity generation in SA being lost (referred to as a Black System). This automatic-protection operated in less than half a second at 16:18. The event resulted in the SA regional electricity market being suspended.

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179 thoughts on “Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings

  1. Can’t be any clearer than that. Thank you Mr. Hogan. I can’t wait to see comments from Griff and Nick Stokes.

    • Oh, they won’t likely say anything. I don’t know about “griff” but Nick Stokes has never ever been able to admit he’s been wrong on anything here or at other blogs, even when he’s been clearly called out on it.

      • “according to AEMO’s own report, three 275 kV transmission line faults were reported at 16:17:33, 16:17:59, and 16:18:08 resulting in three 275 kV transmission lines out of service (and one unaffected). Only at 16:18:09 did the 123 MW reduction in output from the North Brown Hill Wind Farm, Bluff Wind Farm, Hallett Wind Farm, and Hallett Hill Wind Farms occur, followed at 16:18:13 by three more 2745 kV transmission lines going out of service. At 16:18:15 there was a 86 MW reduction in output from the Hornsdale wind farm, followed immediately by a 106 MW reduction in ouput from the Snowtown 2 wind farm.

        At this point, at 16:18:15, flow across the Heywood Interconnector with Victoria increase to over 850 MW, followed at 16:18:16 by complete supply lost to all South Australia region of the National Electricity Market.”

        Well, that’s a busy 8 seconds…

        There are 2 more enquiries in the pipeline, so I think I’ll wait and see.

        So far, I have seen no explanation as to why the wind dropped out or that it was somehow a unique circumstance to wind power.

        Normally 3 lines going out in seconds would be enough to trip any power grid.

        This was an exceptional storm and outage and I still maintain that a grid on any power source would have cut.

        The counter argument seems to me to consist only of ‘SA had renewables so they must have caused it!’

      • The wind cut out because the fans exceeded their safe operating speed and had to be cut. This happened in seconds, which you can see if you look at the charts of wind power generation that have been posed in other threads at this site.

      • So CYA’ith: Griff – October 5, 2016 at 3:13 am

        So far, I have seen no explanation as to why the wind dropped out or that it was somehow a unique circumstance to wind power.

        “DUH”, the wind didn‘t “drop out”, …….. it was surely the wind turbines themselves that “dropped out” because of the high wind speeds.

        Excerpt from above article:
        The predicted weather front moved through SA on the afternoon of Wednesday 28 September 2016, including high winds, ……

      • Griff, the question I think you are asking is why would turbines cut off. Assuming that is the question, the answer is that they are designed to operate in a set wind speed range. Exceed it, and the turbine will feather the blades to protect them from wind damage. A large gust can do that.

      • From the AEMO Preliminary Report, 5 October 2016:

        After losing three 275MW transmission lines north of Adelaide-

        “Generation initially rode through the faults, but at 16:18, following an extensive number of faults in a short period, 315MW of wind generation disconnected(one group at 16:18:09, a second group at 16:18:15) also affecting the region north of Adelaide.

        The uncontrolled reduction in generation resulted in increased flow on the main Victoriam interconnector(Heywood) to make up the deficit.

        This resulted in the Heywood Interconnector overloading, To avoid damage to the interconnector, the automatic-protection mechanism activated, tripping the interconnector. In this event, this resulted in the remaining customer load and and electricity generation in SA being lost (referred to as a Black System).”

        The key point, at this time, seems to be that an uncontrolled reduction(315 MW of generation within 6 seconds) tripped an automatic-protection mechanism.

        The keyword is “uncontrolled”. The scenario seems to show that poor control of the grid system(the inability to isolate sections to prevent overload and the inability to control when generators and substations cut out) caused the problem. It would seem that with 610MW coming in through 2 interconnections with Victoria at least 1/3 of the state could have been kept alight.

      • 315MW dropping out should not destabilize the grid. It is built to withstand much larger drop out when conventional plants suddenly go off line. Perhaps that was too much when combined with the transmission lines going down, but there is another issue.

        Why did all the wind power go off at once? A gust will cause individual turbines to shut down, but it should not happen to all the turbines at once since the gust arrives at different turbines at different times. One thing that could cause the synchronized shutdown of all turbines would be the grid going down, so there was no where to send the power. All generators would have been shut down more or less simultaneously in that case.

      • Well, Anthony, looks like you underestimated the total-denial quality of the professional hack to rationalize away any contradictory evidence, no matter how obvious.

        Remember these two axioms: “Never underestimate how stupid people are.” Closely followed by: “You will ALWAYS underestimate how stupid people are”

        If you doubt me, just take into account the fact that Copenhagen took place literally during the Climategate scandal, after which they spent 6 years rationalizing THAT away, so they could make it worse in Paris.

        Reality makes not even a dent in the prefrontal lobes.

      • “Why did all the wind power go off at once?”
        Mike, the report says quite a lot about that. It happened at times of grid instability caused by identified line failures. chrism explains here. Basically wind generators have to emulate a synchronous generator based on the grid as they see it, and if what they see is too unstable, they just have to disconnect.

      • Thanks Nick, that makes sense. So the power lines going down started the crisis; the grid might have survived that if the initial instability had not forced the wind farms to shut down, which then forced the grid over the edge. The question then is whether that is a necessary attribute of all wind farms (in which case it is a serious problem) or if it is avoidable. From the later reports it seems that the South Australia wind farms may not be up to snuff with respect to such problems.

      • “Normally 3 lines going out in seconds would be enough to trip any power grid.”

        Here in the US and Canada, there have been far more damaging storms — especially ice storms — that did knock out power to sections of the grid but an entire state’s grid failure has never occurred. It is a power grid, not a power straight line or power circle, it’s constructed as a grid for redundancy and reliability.

      • Mike M.,
        “From the later reports it seems that the South Australia wind farms may not be up to snuff with respect to such problems.”
        Limiting the output was a response that preceded this report. They also imposed some new rules about the interconnector.

      • RWturner:

        I don’t know about entire states, but the US northeast blackouts of 1965 and 2003 affected some 50 million people across several states and provinces. The South Australia event only affected 1.7 million people.

        Recovery from the 2003 blackout included MIT providing enough power to get Cambridge MA restarted and that was used to get larger plants in the Boston area back up.

      • The AEMO report on timings is interesting but it is a pity that they don’t give line ratings or flows or how the 132kV lines interact with the higher voltage grid.
        However, going through the data and the grid map, when the Davenport Belalie line went off, that may have caused the trip of the Bluff and North Brown Hill wind farms. It depends how the switchyard was configured. That means those trippings might have happened to any generator. The same may have happened to Mt Lock windfarm when the Davenport Mt Lock section of the line went out. But Horsdale and Snowtown should not have tripped. Brinkworth Templers West line tripping shouldn’t have forced off any generators.
        However with all the line failures, there was still the line Para to Davenport through Bungama. I don’t know the rating of this line. Davenport is up by Port Augusta and most of the load is round the Adelaide are to the south. That means that most of the generators were on the load side of the lines failures. They should not have tripped. It also means that the people blaming it on the weather/ lines failures are wrong.
        This could be why the AEMO is restricting the output of the windfarms. They have met grid compliance codes.

  2. But that’s heresy, you can’t go around suggesting ‘green energy’ is a load of crap.
    Wind mills failing because of too much wind !!!
    Next you’ll be telling us that solar panels don’t work at night.

      • SARC tags are mandatory. Remember, we have Greens and other Climate Faithful who read WUWT as well. These are people who can’t even understand that ‘Mike’s nature trick to hide the decline’ was an actual trick used to hide a decline. Heck, half of them still believe Gleick’s forgery was true.

        Never underestimate the capacity of the true faithful to believe anything is the literal truth if it fits with their dogma.

  3. The Premier of SA was on the radio earlier saying the report was conclusive that the outage was due to damage caused by the wild weather .
    As an OT I just noticed our BOM have a new “homogenisation ” scam going , this one involves changing the levels of minor and moderate flooding .
    Anyone care to guess which way the levels changed ?

  4. Most windfarms have next to no low voltage ride through capability. What that means is that if a fault occurs on a line near the generator, the line voltage drops. If the plant is a synchronous machine, it has inertia that allows it to keep turning until the protection has cleared the fault and the voltage recovers. However, the windfarms have AC to AC converters that need the output voltage to stay within quite tight limits as it uses the frequency, phase and voltage a the triggers for the electronics which create the artificial AC sine wave.
    All the above means a voltage drop in the transmission line fo/from a windfarm will cause the windfarm to switch off. When that happens as it did in SA, the system just cascades down. Load is greater than generation, voltage drops and the lines from Victoria feeding in have to suddenly ramp up. The protection then shuts them off and its all over.

    • Yes. The wind farms have trouble synchronising with an unstable grid, and switch off. The Vic interconnector switched off too because of grid instability, but noone seems to think that makes it the basic cause of the blackout.

      • Don’t you really mean that the grid has trouble stabilising with unstable wind farms? But then that wouldn’t suit your purpose, would it?

      • Too clever by half, Nick. The truth is that wind farms REQUIRE a stable, synchronized grid, but they are UNABLE to provide such themselves. This means that any grid dominated by wind (or solar) power production will inherently be unstable. QED.

      • Ah Nick Stokes, as dense, unapologetic, and as obtuse as ever.

        Nick still doesn’t think wind farms were the cause, because he just can’t accept any fact that conlficts with his AGW driven dogma. Fortunately, thinking people have seen the problem and have taken action.

        TEN South Australian wind farms have been ordered to limit generation in the wake of the disastrous statewide power blackout because the national electricity market operator has declared they have not performed properly. The state’s biggest wind farm, at Snowtown, is among those which the Australian Energy Market Operator has targeted in its “management and analysis” of last Wednesday’s unprecedented power outage as it gradually restores the power network. The move will prompt further questions over whether renewable energy jeopardised electricity grid stability and triggered the cascading blackout, which started when fierce winds damaged 23 Mid North transmission towers and severed three high-voltage lines. –Paul Starick, The Advertiser, 4 October 2016

        Surely this won’t be enough for Nick, he’ll find another excuse rather than admit he’s wrong.

      • Other items in the Advertiser report:

        ““While further analysis needs to be undertaken to identify the cause (of the statewide blackout) and any remedial steps, AEMO must continue to manage the power system to avoid any further risk,” the spokesman said, in a statement to The Advertiser.”

        “AEMO did not respond to The Advertiser’s questions about whether the wind farms in some way contributed to a cascading power grid shutdown, once the high-voltage pylons were toppled.”

        None of this establishes the headline here
        “Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings”
        Nor does anything quoted from the report, either in the head post or comments. The report simply does not say that.

        But, says the Advertiser, the responsible SA Minister puts it more forcefully:
        “The state has not gone black because of renewable energy. The only wind that caused any harm to our grid was the wind energy pushing over our towers.”

      • No Nic. They were on the grid and came off, which made the grid unstable – generation didn’t match load. Heywood came off because all the windfarms had tripped off and this increased the flow from Victoria as it tried to make up the difference – overloaded the lines, causing them to suddenly go from 500 to 900MW in 6 seconds on a line rated for about 750MW. Look at Figure 4. It was the loss of Hornsdale and Snowtown windfarms that caused the overload.
        You have cause and effect mixed up.

      • Chrism,
        “because all the windfarms had tripped off”
        Actually, that isn’t true. Wind was generating 883 MW prior, and six stations dropped 315 MW during the event.
        “You have cause and effect mixed up”
        There was a chain of cause and effect. Grid instability caused the wind disconnect (says AEMO). That loss plus instability (oscillations) caused the interconnect dropout (says AEMO). We don’t know whether the interconnect would have held if the turbines had, especially as another 14 pylons fell after the event.

        And analytik says the turbines amplified the instability. Well, maybe, though I don’t think the AEMO has said that.

      • Nic
        I will give you the benefit of the doubt and say you don’t understand rather than are being a troll.
        The report says:
        ‘The uncontrolled reduction in generation resulted in increased flow on the main Victorian interconnector (Heywood) to make up the deficit. This resulted in the Heywood Interconnector overloading. To avoid damage to the interconnector, the automatic-protection mechanism activated, tripping the interconnector. ”
        To put it in terms I hope you understand.
        The windfarms tripped off. Flow in the line up from Victoria increased until it went over the line limit. This caused the line to trip and SA to go black. That’s it. It did NOT trip because of instability. It tripped because it was overloaded.
        As I explained further up, the lines falling over should have had next to no effect on the grid frequency. It did because there were windfarms. They aren’t synchronous so have no inertia.

      • “It did NOT trip because of instability.”
        Well, the report also said:
        “The reduction in generation during the event, combined with oscillations caused by faults on the
        transmission network, caused the flow on the Heywood interconnector to increase”

        “They aren’t synchronous so have no inertia.”
        As I understand it, they have synthetic inertia, created by the controlled system that links to the grid.

      • Nic
        “As I understand it, they have synthetic inertia, created by the controlled system that links to the grid.”
        No your understanding is wrong
        With regards to the other comments, please actually look at the figures in the report. They show the actual data, though they don’t show voltage. The fluctuations are caused because the wind farms don’t have inertia. That is why the Electranet grid planning report of just six months ago recognized that they would have voltage stability problems.
        ” has identified dynamic voltage control in South Australia’s north as an emerging challenge (section 3.2.1). NPS ceased electricity generation on 9 May 2016.36 As the NPS contributed to network voltage control service at the Davenport 275 kV substation, the withdrawal of NPS creates challenges for transmission network voltage control. “

      • hahaha poor nick trying to go in every turn: i will correct your last statement with the facts (added in bold in your text):

        Yes. The wind farms have trouble synchronising with an unstable grid, and switch off. The Vic interconnector switched off too because of grid instability caused by the sudden loss of 315 MWH due to the tripping of the windfarms which asked a sudden extra power rise on the vic interconnector, which otherwise would not have happened, but noone seems to think that makes it the basic cause of the blackout.

        that’s the actual real cause

        if those 315 MWH generation would have been a “conventional stable power generating plant”, it wouldn’t have tripped and nothing would have happened.

        windmills also require power to work synchronized with the power grid. In belgium we got sometimes days with insufficient wind and a friend working there showed me that at these moments windmill parks do actually use power instead of generating power to keep their synchronicity up and running this on his own company computer showing the real time output of the windmill park.

      • “it wouldn’t have tripped and nothing would have happened”
        You don’t know that. The loss of the pylons caused grid instability, initiating a cascade of events leading to failure. The disconnection of wind farms was an event on the way. There is no way to know whether if that hadn’t happened, something else would not have failed, especially with more pylons blown over after the blackout.

        The inadequacy of the interconnector was another “cause”. If it had had more capacity, there might also have been no state blackout. But no-one seems to nominate that as an “ultimte cause”.

      • i think you are the only one not reading the OEMO preliminary report: the vic interconnector switched off because of the overload that was ultimately caused by the wind farms switching off, because of grid instability (which a power generating source should not do). If they kept working, like a gas, hydro or coal fired plant they switch on the plant’s backup generators and keep producing that 315 MW which would have kept the vic interconnector operating in it’s safety level. (only other exception are nuclear plants as they are in europe ordered to shut down if they need to run on their backup, so nuclear plants are also shut down)

        the detail is in the title: a disaster is always a chain of events, the final link in this chain was the windfarm power generation that ceased to generate power (final link is what “ultimate cause” means). That’s what the report says. A non grid dependant power plant would not have switched itself off, would not have caused the overload of the vic connector, would not have caused the blackout. i think you forget the most important word in the term “power grid” which is the grid.

        in a grid structure every plant is interconnected. When lines fail due to wind they get diverted trough other lines and that in a distributed way that it prevents overload on any of the remaining lines that work.

        in such situation windmill parks which are supposed to keep on generating power to prevent worse, don’t do what they are supposed to do then you create a dangerous situation….

      • “final link is what “ultimate cause” means”
        Well, then, the final link was the shut-down of the interconnector because it couldn’t handle the new circumstances. But I don’t think that is what it means. The ultimate cause was the storm and loss of transmission and grid instability.

      • Arguing about one single “ultimate” cause here is futile. The real question is, what to do about it. My guess is that they will:
        1. Upgrade the interconnector.
        2. Improve the stability of wind generators re the grid, and also their ability to synchronise. I’ve already linked above to what has been achieved with synthetic inertia. oldtimerlex, who seems familiar with the system, says that already have synchronous wind generators, though not enough. They will get more.
        3. Adopt a policy of having more gas turbines spinning when storms are on the way. They have plenty of capacity.

      • Just to jerk the chains of you anti-renewable idealogues. I will remind you of an incident back on the 14th March 2005. In this incident, a transmission line fault on the 275kV Playford – Davenport line tripped the Northern Power Station (coal-fired) generators. The rapid loss of supply then caused the Heywood VIC-SA interconnect to trip and disconnect in exactly the same way as happened in the recent incident.

        580MW of load (or a third of total SA demand) was shed to maintain grid stability. The system was within a whisker of going black. No wind turbines involved at all, it was the coal fired station that went offline due to transmission line instability.

        You can read the full details here

        http://www.neca.com.au/Files/NECA_Report_FINAL_for_14_March_2005.pdf

        Across the whole NEM, transmission line faults happen with reasonable frequency, some are minor with little follow on impact, others are more severe. There’s a nice summary of events from 2006 to 2010 in this document

        http://www.aemc.gov.au/Markets-Reviews-Advice/Review-of-the-Effectiveness-of-NEM-Security-and-Re/Final/AEMC-Documents/Appendix-F-Summary-of-power-system-incidents-that

    • So in extreme case where we have only AC-AC converters where is a perfect sine reference signal coming from?

      Google search reportet one hit on http://www.gps.gov/applications/timing/

      “Power companies and utilities have fundamental requirements for time and frequency to enable efficient power transmission and distribution. Repeated power blackouts have demonstrated to power companies the need for improved time synchronization throughout the power grid. Analyses of these blackouts have led many companies to place GPS-based time synchronization devices in power plants and substations. By analyzing the precise timing of an electrical anomaly as it propagates through a grid, engineers can trace back the exact location of a power line break.”

      Sounds like work in progress, no industry standard yet.

      • “where is a perfect sine reference signal coming from?”
        Chrism explained:
        “However, the windfarms have AC to AC converters that need the output voltage to stay within quite tight limits as it uses the frequency, phase and voltage a the triggers for the electronics which create the artificial AC sine wave.”
        That is what some currently use. You don’t actually need a high power grid to convey this information, and I expect in future there will be alternatives.

        But also doubly fed induction generators are also used. I don’t know how that affects the issue.

      • Fascinating.
        You don’t know what the problem was. You don’t know how it will be fixed. You don’t know what future changes might help.
        But you know beyond a doubt that wind power will work.

    • Well it looks to me we should go to a DC power grid and put inverters at the meter coming into the building. Yeah, that will fix everything.

    • Nic
      I don’t care what your papers say. The windfarms don’t have any inertia. I’m not talking about the airy fairy world of academics and peer reviewed papers. I am talking about the real world here of drop load tests and governor droop.
      The wind farms can’t even do voltage correction. That is why they need switchyards full of capacitor banks. That is why the power station engineers hate them as the farms sponge off the grid. All the normal generators have to jump through all manner of hoops to get grid compliance, but wind farms get a politicians’ mandated free ride.

  5. “Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings”

    It said nothing like that. The AEMO report says upfront, in Sec 1:
    “The root cause is subject to further analysis being conducted and additional information that may be provided. The magnitude of transmission faults due to weather in a short period of time, resulting in significant voltage dips and loss of load, resulted in system instability. This caused some generators to reduce output, increasing flow on remaining power system equipment, causing power system protection to operate to remove risk of damage. Insufficient analysis has presently been undertaken to determine if everything operated as designed during the event. “
    My bold. That clearly says that the cause was transmission faults.

    They list the reductions in wind generation, over a 6 second period and about 16.18. But as the account in the post makes clear, that happened after about two minutes of major transmission failures:
    “In the short time between 16:16 and 16:18, system faults included the loss of three major 275 kV transmission lines north of Adelaide. Generation initially rode through the faults, but at 16:18, following an extensive number of faults in a short period, 315 MW of wind generation disconnected “

    What they say after listing these generator reductions is
    “Additional analysis is required to determine the reasons for the reduction in generation and observed voltage levels before any conclusions can be drawn.”

      • 315 MW of wind generation disconnected (one group at 16:18:09, a second group at 16:18:15), also affecting the region north of Adelaide.

        Here

      • Actually if you were honest perhaps you could explain why they ran the wind farms knowing that the storms were going to be severe that day with high winds that would have been too much for the wind farms shutting them down .

      • “with high winds that would have been too much for the wind farms shutting them down”
        There is no basis for saying that high winds shut the wind farms down. It is most unlikely that that would happen to six separate farms over a period of just six seconds. The first quote is explicit – system instability caused the generators to lose output. They held up until then.

      • So wind farms don’t need to shutdown when severe or damaging wind warnings are predicted .
        And the wind farms that tripped sensed a voltage drop and tripped , if SA was using coal or gas only that day they wouldn’t have needed power from vic and when the lines went down the blackouts would have been localised not state wide .
        We lost power for three hours late yesterday in Victoria , power lines down after a storm and trees on powerlines but it only affected local areas not the state .
        NSW and the ACT also had similar trouble but again localised not the whole state .

      • “There is no basis for saying that high winds shut the wind farms down” Since when has it been a secret that wind turbines go offline in strong winds? This was entirely predictable given the wind direction during these cold front events ( SW – W typically, maybe NW) and the distribution of the wind turbines to the west of the main developed part of the State. So what else ‘shut the wind farms down’?

        Honestly Nick, I think you are deluded if you don’t ‘get it’ that wind farms are vulnerable to extreme winds.

      • PS
        As Eric notes above, the SA ‘government’ were expressly warned by the AEMO.

        Nick, jhat does it take for you to accept that wind is a seriously flawed technology in terms of a robust, secure energy supply system? To be blunt the ‘for’ argument that the energy is “free” (and sshhh, don’t mention the absurd capex required per KW-Hr generated) seems little more than extra ( organically grown of course) sugar in some kid’s ‘be quiet and watch TV’ drink.

      • “So what else ‘shut the wind farms down’?”
        Again, it’s explicitly stated in the report, and explained by chrism56 above. The wind farms were operating until just before the grid went down. Again, I’ll quote:
        “The magnitude of transmission faults due to weather in a short period of time, resulting in significant voltage dips and loss of load, resulted in system instability. This caused some generators to reduce output…”

      • “Nick, what does it take for you to accept that wind is a seriously flawed technology in terms of a robust, secure energy supply system?”
        I don’t think there is evidence for that here. The ABC report quotes Matthew Warren, head of the Energy Council, thus:
        “He said those close to the industry were frustrated by the politics playing out, because there was not one single cause to consider.
        He said South Australia was pioneering renewable energy internationally, which put the state at the cutting edge and meant problems were being solved in real time.”

        The key thing is that problems can be solved. It may take some work. But the key problem here was the transmission failure.

      • Nick Stokes – October 5, 2016 at 2:05 am

        There is no basis for saying that high winds shut the wind farms down. It is most unlikely that that would happen to six separate farms over a period of just six seconds.

        Sorry, Nick S, ….. but that dog won’t hunt.

        “DUH”, all of the wind turbines located in/on a specific “wind farm” ….. never, ever all SHUT DOWN at the same time, let alone in 6 seconds.

        The individual wind turbines located on those six (6) separate wind farms could have started “shutting down” five (5) minutes …… or even ten (10) minutes prior to the “grid shutdown”.

      • Nick Stokes – October 5, 2016 at 3:27 am

        The key thing is that problems can be solved. It may take some work. But the key problem here was the transmission failure.

        Shur nuff, Nick, shur nuff.

        Like the time my vehicle’s gasoline tank went “empty” and left me stranded on the Interstate.

        But I didn’t blame my being “stranded” problem on my own stupidity, ……. I blamed my stranded problem on a “gasoline transmission line failure”.

      • Where?

        Why Nick, it states it right in the preliminary report summation!

        The preliminary report explains how severe weather moved through South Australia on the afternoon of Wednesday 28 September 2016, with high winds, thunderstorms, lightning strikes, hail, and heavy rainfall. The weather resulted in multiple transmission system faults including, in the space of 12 seconds, the loss of three major 275 kV transmission lines north of Adelaide.

        Generation initially rode through the faults, but at 16:18hrs, following multiple faults in a short period, 315 MW of wind generation disconnected, affecting the region north of Adelaide. The uncontrolled reduction in generation increased the flow on the main Victorian interconnector (Heywood) to make up the deficit and resulted in the interconnector overloading.

        To avoid damage to the interconnector, the automatic-protection mechanism activated, tripping the interconnector and resulting in the remaining customer load and electricity generation in SA being lost. This automatic-protection operated in less than half a second at 16:18hrs and the event resulted in the SA regional electricity market being suspended…”

        My bolding.

        Cherry picking interior report clauses that focus on minutiae, but do not summarize to main cause/effect is sophistry.

        Every attempt I’ve made to download the preliminary report has failed. AEMO attempts to download it as an .ashf file. After correcting the extension to .pdf the file hangs during download.

    • Spin all you like Nick – Let me put what happened into laymans terms for you

      Solar input was lost due to cloudiness Load was transferred off Solar

      Some transmission faults happened – which always happen during storms, lightning does tend to prefer to travel through the ionised air near EHV powerlines.

      Wind was lost due to high winds (and other transmission faults) Load was transferred to the interconnector.

      Without the wind and solar inputs there was an overload on the interconnector which dumped SA which ONLY HAPPENED because SA was running insufficient fossil fuel generators to keep the interconnector from tripping.

      Ergo this blackout only happened because the amount of fossil power generation was too low (or if you like renewable generation was too high to guarantee a stable power network)

    • No wonder you like windmills so much. They spin just like you do. Somebody should name a wind farm : Nick’s Spinney.

    • Like most of the apologists for wind power you seem to be conflating root and proximate causes. The proximate cause was surely high winds as this caused in turn a number of disruptions; but a root cause is found in the characteristics of wind turbines themselves, and this points to troubles in the future. One half of the wind generation in SA is type I and II turbines. These most definitely do not provide inertia or frequency support for the grid nor provide any reactive power–they cannot by design. The type III and IV turbines would be capable of some frequency support and could provide reactive power to help the grid pull itself back up from a brown or black state with added equipment; but I am pretty sure that in the interests of promoting affordable wind power the operators of these machines were allowed to opt out of providing a share of these valuable grid services.

      Most of these wind turbines cannot handle a disruption in grid for more than a few tens of milliseconds, hundreds at most. When a report says ” 315 MW of wind generation disconnected “ does this mean a disruption in lines, or did the reactive power capable of feeding the field windings go down? This is why further analysis is required.

      Your insistence that wind power works fine and had no central part in this trouble is akin to saying that a man trying to drag several swimmers to safety in rough or fast water drown because of the water; when his root problem was trying to aid too many non-swimmers.

  6. In the linked report it states:

    “16:18:15.1 (T-0.9s) • 86 MW reduction in output from Hornsdale wind farm.
    • 106 MW reduction in output from Snowtown 2 wind farm.”

    The above two wind farms had an unexpected reduction in output that overloaded the interconnector from Victoria.

    If these two wind farms had not reduced their output, the system would not have tripped.

    I have a sneaky suspicion that if that power had come from a controllable source, the total blackout would not have occurred.

    If you rely upon nature in real time to give you power, then you must allow for nature to do its thing.

    • “If these two wind farms had not reduced their output, the system would not have tripped.”
      You don’t know that. The report says:
      “The reduction in generation during the event, combined with oscillations caused by faults on the transmission network, caused the flow on the Heywood interconnector to increase to approximately 850 – 900 MW by 16:18:15. Flows between 850 – 900 MW are in excess of the design limits of the interconnector”
      “Combined with oscillations”. The system was unstable, because of wind damage to high voltage lines. Then there is a cascade of events. Maybe if the windfarms hadn’t disconnected, the system would have survived. Maybe further damage would have caused a failure later. AEMO isn’t saying.

      One thing is pretty clear – if the coal station at Port Augusta were still operating, it would have been cut off by the failure at Melrose. No better than a wind farm.

      • Garbage. The oscillations were simply an indication that there was insufficient synchronous inertia in the South Australian grid. And why was that? It was due to the stupid price subsidies and priority access to the market that is provided for renewables by stupid regulations.

        If the market was not distorted by the renewables incentives, all of Torrens B, Torrens A and Pelican Point baseload generators would have been online instead of just 3 of the Torrrens B units (+ the Labrokes and Hallett peaking plants). Then, when the pylons fell, the grid would have been split and Adelaide would not have blacked out since all the above plants are located close to Adelaide (and were, in fact, powered up through the Heywood Interconnector to begin the recovery of the South Australian grid). The whole of South Australia would not have blacked out

        If the Northern coal plant at Port Augusta has stayed in operation, then the grid split would not have blacked out the north west of the state, either. There would have been small blacked out sections around the pylon collapses.

        Any discussion about the Northern coal plant and even pylon collapses is a distraction from the fact that the wind farms provide no inertia to help stabilise the grid.The fact quite a number tripped first, before the thermal generators and the Heywood Interconnector, shows they are unstable in the face of disruptive grid events .

      • “One thing is pretty clear – if the coal station at Port Augusta were still operating, it would have been cut off by the failure at Melrose.”

        If you read the AEMO report, Appendix A, you’ll find a diagram of the grid. The Port Augusta coal station attaches directly to the Davenport node. Whilst the were several line failures you’ll find the Davenport/Bungama/Para line remained operational.

        So no, The Port Augusta coal station would not have been cut off.

      • I haven’t dug through the maps, but the wind turbines may be quite a ways from the customers. If their power generation was closer, they wouldn’t have been in that strongest part of the storm and they’d be on shorter connectors. Wind may be free, but the costs of getting its energy is phenomenal.

      • “but the wind turbines may be quite a ways from the customers. “
        They are mostly a lot closer than the Port Augusta coal generators were. And those were still a long way (230 km) from the coal, which had to be railed. In fact what counts is how far are the turbines from the nearest trunk power line.

    • The warning you cited was this:

      “AEMO has modelled the impact of withdrawing a further 1,360 MW of coal-fired generation capacity to meet the COP21 commitment under AEMO’s neutral scenario, with results suggesting potential reliability breaches occurring in South Australia from 2019-20, and New South Wales and Victoria from 2025 onwards.

      “These breaches would most likely occur when demand is high (usually between 3-8pm), coinciding with low wind and rooftop photovoltaic (PV) generation, and low levels of electricity supply imported from neighbouring regions.

      “In this scenario, the majority of coal-fired generation withdrawals are assumed to come from Victoria, which would reduce that State’s generation output to support South Australia and New South Wales via the interconnected network,” said Mr Cleary.

      Here the wind generation was not low, and nor was the import. But more specifically, they are not talking about the response of the grid to transmission failures inducing instability.

    • When I lived near the Tehachapi wind farm, I could tell in the morning if it was going to be extra windy later that day. The turbines would shut down in expectation of excessive wind speed. I assume that was done manually by the operators reading the forecasts.

  7. The question one has to ask is:

    If there were no windfarms whatsoever in SA, and all power generation was by conventional fossil fuel generation, would there have been a state wide blackout, or only localised blackouts?

    If there had been no windfarms ever built and if there would in this circumstance have been only localised blackouts, it is obvious that the problem is due to the incorporation of wind energy into the energy infrastructure and mix.

    Prior to the introduction of windfarms, has there ever been a state wide blackout caused by a bit of stormy weather similar to that encountered about 1 week ago? Perhaps our Australian friends can answer that.

    • When the Beatles came to Sydney in 1964 there was a state wide blackout in NSW, but its just a coincidence.

    • “If there had been no windfarms ever built”
      If the state was relying on power from coal at Port Augusta, it would have been worse. Two lines that went down early were Davernport-Brinkworth and Davernport-Belalie. These carried most of the power from the coal generators to Adelaide.

      From memory, there was a similar blackout in SA in about 1997.

      • Nick @ 3:37

        “If the state was relying on power from coal at Port Augusta, it would have been worse.”

        What could be worse than no power throughout the state?

        Also presumably if there were no wind generators built in recent times the SA govt would have built more fossil fuel capacity or better interstate connectors.

      • “What could be worse”
        It would have been a larger loss of power, so with all your other might-have-beens, the effect would have been severe. In fact there was enough spare capacity – Torrens Island alone has 1280 MW capacity. Just not enough spinning at the time.

      • And Torrens A, Pelican Point and one of Torrens B’s units weren’t up because of the pricing subsidies and market priority that wind farms are given.

        BTW if the Northern coal plant was still up while Adelaide blacked out, it still would not haven been a full state blackout and Northern would have provided the power to recover the Adelaide generators rather than Heywood.

    • not in my memory at 57yrs old..and having been in SA for some truly crap weather before this event
      which was bad but the mid nth especially has quite regular mini tornados whizz through
      redhill about 8 yrs ago, hallet ,and farrell flat and other spots in the last 15yrs
      I was frankly gobsmacked when they wanted to put the Bute hills/snowtown birdshredders in
      as the quite regular huge winds there summer and winters were obviously placing them at risk of damage/inability to work.

      • NIck @ 4:08

        Presumably Torrens Island gas was not spinning enough at the time because they were relying on the wind supply?

      • Torrens A, Pelican Point and one of Torrens B’s units weren’t up because of the pricing subsidies and market priority that wind farms are given.
        That’s 1158 MW of additional synchronous generation that could have stabilised the grid but were offline due to market distortions.

    • Well Richard there are many examples of power outages listed here:
      https://en.wikipedia.org/wiki/List_of_major_power_outages

      some of them from wind storms. It is a long list, so I haven’t looked for an Australian outage due to wind.

      for example:
      “On 29 August 2015, A powerful windstorm knocked out power to 710,000 customers (Nearly 50% of BCHydro’s Customers) on Vancouver Island and Vancouver’s lower mainland. 705,000 customers had power restored within 72 hours of the storm. This was BCHydro’s single largest outage in BCHydro’s history.”

      This is in a place mostly powered by hydro

      • Griff, I have lived in BC all my life (i’m 58). We have these big windstorms every 10 years or so. The loss of power (electricity) is entirely due to thousands of trees falling on power lines.

      • same here in Belgium: the biggest blackout was in the 1990’s during a series of severe windstorms. on a population of 10 million, 1.5 million were without power. However the main lines (except one partially) did hold. The only damage were from falling trees. (the main line that partially got damaged was also because of a tree taking the 2 lowest lines with it as it fell down).

        Now a similar scenario would put at least half of our country in the dark as when the north sea windmill park trips for the same reason, (unstable feeder lines) the whole grid of that sector would cascade down into a blackout.

  8. Pie Chart:
    Figure 1 SA generation mix pre-event

    In that system is a lot of engineering dangling in the air…very vulnerable I’d say and on this occasion the catastrophic event that risk analysis (modelling?) should have adequately mitigated…arose!

    I don’t like anything about the way wind has been rapidly crow barred into controllable systems. However, Fig 1 definitely shows the foolishness of employing so much of it….and not adequately controlling it. Its a very large percentage. It would be interesting to see the damage reports/claims..if possible.

    In the sequence of events power lines went down first and suddenly followed by Wind supply and which existing Thermal could not handle. Not the degradation type that you would want in a very short space of time. I don’t think its a case of too many power lines (likely never will be), too many Wind machines is seriously wrong.

  9. It is interesting to note that the enduring media image of this event – the line of downed power transmission towers – may have actually occurred after the state went black.

    “Following the SA Black System, ElectraNet advised AEMO of network damage resulting from the storm.
    This included:
    • Davenport to Mt Lock and Davenport to Belalie 275 kV line – 5 double circuit towers damaged.
    • Brinkworth to Templers West 275 kV line (East circuit) – 2 towers damaged.
    • Davenport to Brinkworth 275 kV line (East circuit) – 14 towers damaged.
    • Port Lincoln to Yadnarie 132kV line – 1 tower damaged.

    Data currently available to AEMO indicates that the damage to the Davenport – Brinkworth 275 kV or
    the Port Lincoln – Yadnarie 132 kV lines occurred following the SA Black System. “

    • This would shut up shop for the green gov of SA and other states if it gets proven , too much at stake for any tangible proof to get out that the towers went down after the blackout .

    • ” may have actually occurred after the state went black”
      No. From the report:
      “At 16:17:33, Brinkworth – Templers West 275 kV line tripped due to a two phase to ground fault. No automatic reclose was attempted on this line.”
      “At 16:17:59, there was a single phase to ground fault on the Davenport – Belalie 275 kV line. The faulted phase tripped out of service”
      “At 16:18:13, there was a single phase to ground fault on the Davenport – Mt Lock 275 kV line. The faulted phase tripped out of service”

    • AEMO says “three 275 kV transmission line faults were reported at 16:17:33, 16:17:59, and 16:18:08 resulting in three 275 kV transmission lines out of service (and one unaffected). Only at 16:18:09 did the 123 MW reduction in output from the North Brown Hill Wind Farm, Bluff Wind Farm, Hallett Wind Farm, and Hallett Hill Wind Farms occur, followed at 16:18:13 by three more 2745 kV transmission lines going out of service. At 16:18:15 there was a 86 MW reduction in output from the Hornsdale wind farm, followed immediately by a 106 MW reduction in output from the Snowtown 2 wind farm.

      At this point, at 16:18:15, flow across the Heywood Interconnector with Victoria increase to over 850 MW, followed at 16:18:16 by complete supply lost to all South Australia region of the National Electricity Market.”

      So some lines were out before the first wind trip and more went before subsequent ones.

      • And if the tripping wind generators were not powered by wind they would not have tripped due to the wind!

      • Griff has the sequence correct.

        And what it shows is that the wind farms themselves have poor stability on top of providing no stability for the rest of the grid, Top stuff!

  10. I think the correct phrase to use to describe the posts by Nick and Griff would be if they actually had said what they posted…”Open mouth. Change foot!”

    I used to wok with people who built power stations in the UK and gained my 240v/ac single phase and 415v/ac three phase electrical training and experience in the UK and neither you Nick, and certainly Griff as he seems to get his information from The Gaurdian, have ZERO understanding of how power generating and transmission systems actually work.

    The article by Mr. Hogan is SPOT ON!

    You too are too funny!

      • Your total ignorance is showing Stokes. When people dig themselves in to a hole neck deep in sheet, it is advisable to stop digging!

      • “Nick Stokes October 5, 2016 at 4:10 am

        I see no evidence…”

        Assumption Stokes, assumption. And talking of evidence, actual real world evidence, I see no evidence that ~3% of ~400ppm/v CO2 is the driver of climate change and bad, 50 year, weather events, only to get worse, apparently.

    • I cite the Guardian and similar when they have good summaries of a piece of research, etc.

      But I would always expect people to look at the link to the research etc, as I do.

  11. If someone with a peanut allergy eats a peanut and dies, was it caused by the allergy or the peanut? Some might argue that lots of people eat peanuts with no problems-hence it was the allergy. Others might argue that lots of people have peanut allergies with no problems-hence it was ingesting the peanut. Most of us can recognize the contributory roles of both conditions and are quickly bored by those who drone on dismissing the roles of one or the other. .

    Had the storm driven line outages not occurred, the asynchronous intermittent generation would likely not been a problem in of of themselves at this time. Had the system contained a higher ratio of synchronous rotating generation rather than renewables, the system response would have been less problematic and likely the blackout would have been avoided in this case.

    The key point is that the system built there with high penetrations of renewables was less economic and less reliable than the system would have been with significantly lower levels of penetration. There may be good arguments that the societal benefits outweigh the cost and reliability tradeoffs. But you must be ignorant, irresponsible or plain deceitful to dismiss reliability implications.

    • Thanks for that rather objective observation, aplanningengineer.

      On the whole, I am enjoying this post and the charged debate that follows. It is obvious to the casual reader where sanity and logic are applied versus dogma and dig-in-your-heels, wearing-the-blinders (blinkers to you all over or under the pond) approaches as to what actually happened in this weather event and the subsequent grid failure. Interesting, and enlightening. Just one in a long list of reasons why I keep coming back to WUWT.

      Regards,

      MCR

  12. I read the AEMO report. It’s preliminary so it doesn’t identify the reason for the big drop off in wind power. The suggestion from commenter chrism56 is reasonable, that the lack of fault ride-through capability is the reason. The report doesn’t comment on this. Countries that are expanding their wind power network are also updating their codes to require fault ride-through.

    Here is a quote from Overview of Recent Grid Codes for Wind Power Integration, Altin et al, 2010:

    “Conventional power plants, which are composed of synchronous generators, are able to support the stability of the transmission system by providing inertia response, synchronizing power, oscillation damping, short-circuit capability and voltage backup during faults. These features allow the conventional power plants comply with the grid codes, thus today TSO have a quite stable and reliable grid operation worldwide.

    Wind turbine generator technical characteristics, which are mainly fixed and variable speed induction generators, doubly fed induction generators and synchronous generators with back to back converters, are very different to those of the conventional generators. As the installation of WPPs, which consist of these wind turbine generators, has reached important levels that they have a major impact on the characteristics of the transmission system [1].

    Therefore, the grid codes demand WPPs to behave as much as similar to the conventional power plants for maintaining power system stability and reliability. Simultaneously the wind turbine manufacturers have been challenged by the new grid codes as they must adapt their technology to satisfy these grid codes..”

    and later:

    “For instance, countries with a weak power system, such as Ireland, have considered the impact of wind power on network stability issues, which means that they require fault ride-through capabilities for wind turbines already at a lower wind power penetration level compared with countries that have very robust systems. The inclusion of FRT regulations for DFIG noticeably increase overall cost by 5%.”

    If the SA grid code doesn’t require FRT they will no doubt be updating their code. They may already have updated their code but probably only for new connections. I don’t know.

    The item that stands out in the report (but isn’t “highlighted”) is that the interconnector to Victoria was basically being run close to maximum (there is a discrepancy in the report which seems important but it has only been a few days since the event) and so the risk of a black event seems high.

    Grid operators do this kind of stuff for a living, so perhaps one wind farm shutting down due to a local voltage fault was allowed for and the actual results was outside their risk analysis. Perhaps their wind farms do have fault ride through capability and it failed for some reason.


    In any event, there are issues with putting lots of wind onto a network. As well as needing fault ride-through, the maximum System Non-Synchronous Penetration (SNSP) is an important grid parameter. But there are many 100s of papers on these topics. It isn’t something that is ignored, as we can see by the way that many European grid codes have been updated with new requirements for wind generators.

    It seems like these issues are just problems with practical existing solutions. From time to time, people make mistakes, or misjudge risk. Other people (and sometimes the same people) learn from these mistakes. There were floods in Brisbane a few years ago because people made mistakes in judging where the risks were – not because there is a fundamental problem with using dams to store water.

    Perhaps SA has been cavalier with growing its wind power generation and not taking into account the risks. Perhaps the event was outside the risk profile they were required to cover. Perhaps there were other problems that remain to be uncovered. But wind power is a just a resource that has statistics associated with its availability. These are not insuperable barriers to its use.

    • This report by the AEMO and ElectraNet nicely outlines the issues that South Australia was letting itself in for. Some of the scenarios describe are not hugely different to what took place last week.
      https://www.aemo.com.au/Electricity/National-Electricity-Market-NEM/Security-and-reliability/-/media/CACEB2122362436DAC2CDD6E8D3E70D0.ashx

      And the following letter to the AEMC in July by the South Australian Energy Minister, Tom Koutsantonis shows that the government knew they were in dire straights given the right (or wrong) conditions. See Section 1 of Attachment A (page 10) for the requested rule change and the reason.

      To limit the RoCoF [Rate of Change of Frequency] to acceptable levels, when South Australia is at credible risk of separation, AEMO will invoke network constraint sets to limit flow on the Heywood lnterconnector based on the amount of online inertia available in South Australia. This is required so that, in the event of a credible contingency event resulting in separation of South Austraiia from the rest of the in the islanded South Australian region can be managed and the separated systems maintained in a secure operating state

      http://www.abc.net.au/news/2016-10-04/electricity-security-complex-in-sa-says-koutsantonis/7899302

      And yet this same minister had been making public statements that all was well with the South Australian grid, right up until the blackout.

  13. This analysis accords with reports made byn
    knowledgeable locals
    Could the rapid drop of 315 MW of wind
    power have been caused by automatic
    feathering down of the wind vanes to
    protect the wind farms from excessive
    wind forces?
    If this is the case it highlights the relative
    fragility of wind power
    It also means that in three months the SA
    40% wind reliant electricity system has
    twice been adversely affected
    In July when there was insufficient wind
    to turn the vanes
    In September when it seems there was too
    much wind!

    • Thomho sums it up rather well:
      “Could the rapid drop of 315 MW of wind
      power have been caused by automatic
      feathering down of the wind vanes to
      protect the wind farms from excessive
      wind forces?
      If this is the case it highlights the relative
      fragility of wind power”

      Wind is crap power, only helping those insiders who get the forced-purchase agreements.

  14. Seems clear to me, by looking at page 27 of the report, that the two wind stations that went offline (Hornsdale & Snowtown) are in a north/south line, directly under the central effect of the storm front at the time of failure.

    Now, it could be coincidence that a 10 year storm was passing over two wind farms in question at the time they failed, but I feel that the initial thoughts of too much wind are correct.

    The tripping speed of these machines (~25m/s) is below that experienced in the area as stated on page 24.

    I think it is time for some people to admit that a wind powered device that is designed to shut down during a high wind speed, will, shut down during a high wind.

    Combined with insufficient despatchable generation elsewhere within the system caused the blackout.

    The same thing may happen in the UK this coming winter. Our wind penetration is much lower, (4% ~5%) but our overcapacity has been reduced to historic low levels.

    See what is published by the UK Government about too much wind causing a blackout:

    “Mitigation measure – 5

    Storm ride-through turbines
    • During the winter of 2011 – 2012, there were a number of
    storm events in UK, each causing a large number of
    turbines to close down simultaneously, for self-protection

    • These events caused a major deviation of wind turbine
    output from that forecasted
    – No national blackout occurred
    – Sufficient reserve must have been previewed & in place
    • From a then fleet capacity of just over 5000 MW, the
    deviations from forecasted were in the range of 2400 MW
    • A much larger fleet of similar turbines could result in a grid
    ”event”
    from:
    https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/253178/Technical_mitigation_of_imbalance_risk__analysis_by_Mott_MacDonald___Presentation_at_April_workshop_.pdf

    • North Brown Hill Wind Farm, Bluff Wind Farm, Hallett Wind Farm, and Hallett Hill Wind Farms all went off at the same time – 16:18:09. There is no way they all oversped at the same instant- they tripped due to the short circuits from the falling pylons. Hornsdale & Snowtown2 then tripped after the next short circuit 6 seconds later.
      Half a second after that, the Heywood Interconnector tripped and it was only then (another half second later) that the 3 Torrens B unit and 3 peaking plants that were online tripped, blacking out the state,

      Lack of stability was the issue and the fact that so many wind farms tripped before the blackout shows they are not stable in the face of disruptive network events.

      Meanwhle, the pricing subsidies and priority access for renewables meant the wind farms had driven most of the gas baseload generators offline making the grid only marginally stable in the face of the inevitable short circuits and power surges that occur during large storms.

    • “The same thing may happen in the UK this coming winter. Our wind penetration is much lower, (4% ~5%) …….”

      In the past 12 months GB’s peak demand was ~43GW. As of the end of Sept 2016, overall UK wind capacity stood at 14.1 GW. However, despite the addition of ~0.45GW since end of last year, our turbines appear to be constrained-off at ~6.5GW, a figure unchanged for some time.

    • A possible way to help this is for the turbine operators to shut them down in an orderly and coordinated manner before the wind speeds get too close to their automatic cutoff speed.

  15. steverichards1984,

    “I think it is time for some people to admit that a wind powered device that is designed to shut down during a high wind speed, will, shut down during a high wind.”

    This isn’t a secret, or something not admitted. It’s in all the textbooks on wind power. It’s in the papers. No one in the field of power generation claims anything else. For example, page 5 of the textbook “Renewable Electricity and the Grid”, Edited by Godfrey Boyle, 2007:

    “Wind power, like wave power, requires the generating plant to withstand extreme conditions without being destroyed. Wind turbines are currently designed to withstand maximum wind speeds of usually around 25 metres per second (m s−1), at which level the turbines are switched off for protection. Figure 1.3 illustrates a typical power output characteristic for a wind generator showing output rising from a cut-in wind speed of about 4m s−1 to 5m s−1, to a maximum output at about 13m s−1 to 14m s−1 and a shut down speed at 25m s−1.”

    I don’t think I can display fig 1.3 in this comment, but it paints exactly that picture. At high speeds wind turbines shut off. Not in dispute.

    Likewise everyone working in the field knows and states that wind is intermittent. Some of the time there is no power from wind in a region. Not in dispute.

  16. What is it about wind that inspires such undying loyalty, such as nearly religious admiration, seeing the turbines as an alter to Gaia and never seeing the impracticality, the huge damage to the planet, the government graft? Complete emotional attachment untouched by reason or science. Fascinating.

  17. When you’re in deep doo doo the best form of defense is attack according to the Premier-
    http://www.adelaidenow.com.au/news/south-australia/multiple-faults-led-to-huge-south-australian-blackout-preliminary-report/news-story/f9d66b196d1756a4ed1af8a899a387df

    And just for Nick and Griff to get up to pace-
    http://www.heraldsun.com.au/blogs/andrew-bolt/wind-power-blamed-how-south-australia-went-black/news-story/8b50878e1577563477acdb9d30cfee30

    and don’t miss the Andrew Dodson video chaps
    https://stopthesethings.com/2016/09/29/another-statewide-blackout-south-australias-wind-power-disaster-continues/

    I can tell you the ordinary punters are not happy at having been lied to about unreliables and the watermelons are running about like headless chooks in damage control. As for the AEMO they’re acutely aware of the political fallout and are couching the bleeding obvious as mildly as they can to leave the bunfight to the pollies. Another State blackout in peak summer heatwave season (bearing in mind Victoria’s weather is at best 24 hours behind South Australia) and that will finish these dark Satanic mills for good.

      • Yes he’s enlightened me as to why these disperse unreliables are a major cause of the high prices we’re paying for power when you consider the extra infrastructure, resourcing and brainpower needed to hang it all together. Nevertheless from what he’s saying, it’s an increasing nightmare to manage and the complexity of it all leads to knife edge vulnerability, nowhere better demonstrated than in SA by the looks, because we’re at 40% unreliables.

    • Without some form of rapid response backup generation capacity, it cannot be avoided. Here on the west coast of the U.S., “peaker plants” that use jet turbines can come online almost instantaneously. So-called co-generation plants that use biological waste for generation also fill in, but they can’t respond as rapidly as either jet turbines or hydroelectric generation. Wind generation is an ugly (visually) joke. The turbines usually are seen operating on nice days in moderate winds. Wind farms located to take advantage of notoriously windy notches discovered that the locations were too windy. I can only imagine that “entrepreneurs” noted the potential for wind generation based on how windy the places were and looked for funding without discussing things with an engineer or three.

  18. With Port Augusta thermal gone and Torrens Island and Pelican Point under the pump, this news coupled with our State blackout, due ultimately to the eastern interconnector shutting down, has suddenly made South Australians acutely aware of the folly of unreliables-
    http://www.dailyadvertiser.com.au/story/4186258/hazelwood-shutdown-victorias-dirtiest-power-station-set-to-close-early-next-year/
    We live in interesting times and sooner or later these watermelons were going to have to face up to real science.

  19. From the AEMO ‘Market Notices’ site-

    ‘55242
    05 Oct 2016 19:52
    Heywood interconnector dynamic constraint
    AEMO ELECTRICITY MARKET NOTICE
    Heywood interconnector dynamic constraint
    Under the market suspension in South Australia, AEMO will limit the flow from South Australia to Victoria to prevent the accumulation of negative residues, which cannot be accommodated under the suspension pricing regime.
    The following constraint set has been invoked at 20:00 hrs to manage the above outcome.
    Constraint set: I-SV_000_DYN which includes constraint equation: S_V_000_HY_DYN.
    Spot prices and ancillary services prices in South Australia continue to be determined by the relevant market suspension pricing schedule developed and published in accordance with clause 3.24.5(l) of the NER. The schedule is available on AEMO’s website at
    https://www.aemo.com.au/Electricity/National-Electricity-Market-NEM/Data/Market-Management-System-MMS/Market-Suspension-Default-Pricing-Schedule and summarised for South Australia at https://www.aemo.com.au/Media-Centre/Prices-in-South-Australia

    Manager NEM Real Time Operations’

  20. Had trouble posting that copy so I’ll comment here. SA had come under Emergency Service legislation (according to a notice yesterday which has dropped off) and that meant SA was exempt from despatch pricing but notice now they’ve told the 10 wind farms to limit any output so they won’t feed any power back east, presumably because they need all the transmission capacity free to sustain reliability to SA under the circumstances. In other words keep your stinking wind, SA needs real power now.

      • ‘he’s a paid commenter, rather than an honest one.’

        He certainly seems to have a lot of time on his hands, doesn’t he? Not encumbered by a pesky day-job… unless of course, this is it.

    • Anthony,
      My original contention was that the report says nothing that justifies your headline:
      “Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings”
      No-one else has quoted anything. The simple fact is that the report does not say that.

      As far as wind turbines is concerned, the pretzelling has been in the endless lines of attack mounted here. First they were mechanically unreliable. No-one could build that many and keep them working. Then they were intermittent and the system would fail for lack of power. But in fact they stood up when pylons were failing, and they provided power right until the grid became unstable.

      Now the complaint is that they disconnected when faced with an unstable grid where they could not supply in phase. That seems to be true. It is also likely to be fixable. The AEMO is trying to manage that. But an unstable grid with loss of multiple pylons is not a common occurrence. The interconnector also disconnects in those circumstances.

  21. @Nick I appreciate that you come and comment. (Seldom your tone or demeanor but…)
    @the_rest Very few on ‘Nick’s side’ bother to come and attempt to converse, and yes even though he appears to be wearing horse blinker’s at all times he actually contributes. If this place was ‘only preaching to the choir’ I would not remain long. If you have seen the original ghostbusters, I view him as Louis Tully at the party before he gets cornered and becomes “the Keymaster”.

    • i too consider this site all the better for the likes of Nick, and I consider that.generally Nick’s demeanour is very good especially as he is sometimes the butt of some outrageous ad homs. Consider the recent snipes of CoB that Nick is ‘mathematically challenged’. Given the amount of maths that most of us have forgotten, I am sure that Nick’s grasp of maths is far better than most who comment on this site.

      Whilst one should take things with a large dollop of tounge in cheek, I cannot see the need to post the above carton with its caption.

      We are adults and we should be able to have a grown up debate letting the facts and the science do the talking.

  22. I have never understood the case for wind.

    Leaving aside the technical issues that flow from the fact that there is little energy in displaced air, and that there is and can be no economy of scale (you know when a technology has run its course, when minaturization no longer occurs), the fact is that wind turbines fail on their primary objective of reducing CO2.

    The evidence has been in for at least a decade. Windfarms do not reduce CO2 because wind is non despatchable and intermittent and requires 100% backup by fossil powered generation and given the manner that this backup runs means that there is no overall saving in CO2 emissions.

    We all know that windfarms on average produce about 22 to 28% of their nameplate capacity. At first glance one might expect this to result in about a 25% reduction in CO2 emissions, but that is not the case because of the backup required from conventionally powered generation. That has been known for at least a decade (I would say even longer than that)

    If windfarms do not result in a meaningful reduction in CO2, what is the point of them? They are unreliable, and expensive. They require huge new infrastructure expenditure coupling them from their remote locations to the grid, and due to the lack of energy in the displacement of air, they require vast tracts of land.

    All windfarms achieve is to put up the price of energy and result in a less stable grid and thereby less energy security.

    It is difficult to see how politicians continue to fall for this sc@m, because that is what windfarms are given that they do not result in the meaningful reduction of CO2.

    Now I understand people having different views on the science of AGW (not least because all but none of the data is fit for purpose and capable of withstanding the rigours of scientific scrutiny), but I find it very difficult to understand how any sentient and rational person could support wind simply because windfarms do not in any meaningful way result in the reduction of CO2 emissions. At that most basic and fundamental level, they fail.. It is more than time that the push for wind was abandoned. A large dose of reality is what is needed.

    • The comment below was made in response to the publication of the 2010 UK Coalition Government Energy and Climate Change Programme:

      philip riley says:

      10 June 2010 at 11:01 pm

      Kinetic Energy is equal to half the mass times the square of the velocity, one mole of air occupies 22.4 litres at 20 degrees Celsius, mass of one mole of air is equal to, as near as dammit, 14.4g. You now have all the information you need to work out why windmills are a complete WASTE OF FU**ING TIME.

      Please, use your head, and think about this….. Nuclear will work, so will ‘fossil fuels’, renewables will not. This really is basic maths.

      http://webarchive.nationalarchives.gov.uk/20100919110641/http:/programmeforgovernment.hmg.gov.uk/energy-and-climate-change/comment-page-19/index.html#comment-11184

      Unfortunately, the commenter was a genius but the politicians weren’t. They continue to build their monuments to folly.

      • As children, we quickly learn that there is no worthwhile energy in the displacement of air.

        Any kid who has played with a water pistol knows that when it runs out of water it has to be refilled because displacing just air, rather than water, does nothing to hit your opponent.

        There is about 1000 times less energy in the displacement of air.

        Storms have a lot of force not simply because of the very high wind speeds but because of the moisture content of the air is often very high. We will see that with Matthew,

        Wind as a source of energy production is plain silly, but my main gripe is that it does not reduce CO2 emissions to any meaningful extent and is therefore completely and utterly redundant.

        PS. I am not one who is concerned by CO2 emissions, if for no other reason that I consider the planet to be way too cold and with far too little CO2, such that if by some happy consequence more CO2 brings about some warming that would be a win win scenario for mankind and bio diversity in general.

      • As children, we quickly learn that there is worthwhile energy in the displacement of air when we fly a kite.

    • I have never understood the case for wind.

      That’s likely because you’re not involved in organised crime.

      Interestingly, SOCTA noted the emergence of economic fraud cases exploiting electricity and gas markets following a scheme targeting carbon credit trading. Apparently, 90% of carbon trading credits in the EU in recent years were driven by fraud.

      Organized crime groups such as the Cosa Nostra, Camorra and Ndrangheta are reported in the SOCTA as being heavily involved in renewable energy (wind and solar) and waste management businesses all over the EU which are used to launder funds.

      With respect to renewable energy, the involvement of organized crime commences at the financing of infrastructure and continues to operating wind farms and solar energy companies. The generous EU subsidies, tax credits and tariff fees are attractive to organized crime because it means ultimately that the government is funding organized criminal activities.

      http://www.duhaimelaw.com/2013/03/21/europol-issues-organized-crime-threat-assessment-focusing-on-cybercrime-hacking-money-laundering-and-drugs/

  23. “The above two wind farms had an unexpected reduction in output ”

    Heh. Unexpected.

    In the words of Inigo Montoya, they keep using that word. I don’t think it means what they think it means.

    Correct me if I’m wrong, but don’t wind turbines shut down when the wind gets too strong?

  24. Having investigated multiple complex power supply disruptions/outages during my career I would suggest that until the investigation is complete the majority of comments/observations above are speculative, some are clearly more informed than others.

    It is essential that the investigation cover not just the timing of the physical events, but extended to the system/process management root causes.

    Grids are not just thrown together, the generation/grid/load structure should, and will almost certainly have been, subjected to “stress testing” during the design. There are various “tools” available to do this. The validity of the assumptions going into such modelled stress testing are obviously critical and typically where “root causes” are found.

    This is speculative on my part but I would not be surprised if it was found that there was some degree of “political interference”, or simply “ill-informed wishful thinking”, that had been applied to the assumptions on wind power generation integration to the grid. Having said the above, no matter how robust the system design, there is always the probability of a “black swan” event. Total redundancy is impossibly expensive. Balancing risk, probability and consequences, against cost is a difficult equation to solve. (From the world of hard knocks a one in ten year total failure event should be considered)

    The fact that the managing authority seems to have decided to limit wind generated power in to the grid as a short term risk mitigation action is informative.

    • While black swan event do occur and total redundancy is impossibly expensive, the fact remains that big storms have hit other parts of Australia, especially Queensland, without bringing down the electricity grid for the whole state.

      Queensland is a good comparison since it is also at the end of the NEM grid, so it can be islanded, and gets hit by severe tropical storms every few years.

      The evolution of the grids certainly required planning and testing as they were expanded. The issue is that all the design and testing was done with the stability of synchronous generators at the core. With so much asynchronous generation from the doubly fed and full converter wind turbines (and the domestic PV), South Australia’s grid was operating well outside the designed parameters for grid stability whenever there was a high amount of wind generation.

      The the following letter to the AEMC in July by the South Australian Energy Minister, Tom Koutsantonis shows that the government knew they were in dire straights given the right (or wrong) conditions. See Section 1 of Attachment A (page 10) for the requested rule change and the reason.

      To limit the RoCoF [Rate of Change of Frequency] to acceptable levels, when South Australia is at credible risk of separation, AEMO will invoke network constraint sets to limit flow on the Heywood lnterconnector based on the amount of online inertia available in South Australia. This is required so that, in the event of a credible contingency event resulting in separation of South Austraiia from the rest of the in the islanded South Australian region can be managed and the separated systems maintained in a secure operating state

      http://www.abc.net.au/news/2016-10-04/electricity-security-complex-in-sa-says-koutsantonis/7899302

      And yet this same minister had been making public statements that all was well with the South Australian grid, right up until the blackout.

      Wind turbines with synthetic inertia may have prevented the statewide blackout at additional cost. But then again. their long recovery times after supplying synthetic inertia (they slow down a LOT after overcurrent events) may have just delayed the inevitable.

    • The fact that the managing authority seems to have decided to limit wind generated power in to the grid as a short term risk mitigation action is informative.

      Bingo!

  25. @Joel Snider October 5, 2016 at 10:16 am:

    Your two axioms would be better stated as:
    “Never underestimate the human capacity for doublethink.”
    “You will ALWAYS underestimate the human capacity for doublethink.”

    There’s a big difference between being unable to know and being unwilling to know, with the latter being much more common – and pernicious. As Orwell put it:

    “Even the humblest Party member is expected to be competent, industrious, and even intelligent within narrow limits, but it is also necessary that he should be a credulous and ignorant fanatic . . . In his capacity as an administrator, it is often necessary for a member of the Inner Party to know that this or that item of war news is untruthful, and he may often be aware that the entire war is spurious and is either not happening or is being waged for purposes quite other than the declared ones: but such knowledge is easily neutralized by the technique of doublethink.”

    • ‘There’s a big difference between being unable to know and being unwilling to know, with the latter being much more common – and pernicious.’

      Agreed. Although it’s sometimes hard to tell the difference. There is also a tendency among intelligent/informed people to assume that everyone has equal understanding – I have discovered this not necessarily to be the case. In fact, WAY too often, I find people’s opinions shaped as much by a general osmosis of information that just trickles in, and people learn it the way they learn a Burger King jingle – just though constant input and repetition. Then you combine that with the natural human trait of balking at anything that threatens your world view, and you get an outright resistance to learning.

      And of course, too much exposure to this type of person results in the second type of intelligent/informed person that assumes everyone else is an idiot.

      And I guess that’s the root of the separation – how much of this organized stupidity is deliberate or just happenstance?

      • ” . . . how much of this organized stupidity is deliberate or just happenstance?”

        Actually, it is neither, with the exception, for a very few influential figures, of the former. You say – correctly – “[often] people’s opinions [are] shaped as much by a general osmosis of information that just trickles in, and people learn it the way they learn a Burger King jingle – just though constant input and repetition.” I say the same is true of their “world view” – their philosophy – and that is what enables the organized stupidity – the doublethink – to operate unchallenged. For a good (disregarding the somewhat naive military apologia) succinct explanation:

        http://fare.tunes.org/liberty/library/pwni.html

  26. I don’t understand why the IPA, a free-market think tank, would genuflect, albeit shallow, to the ravenous renewable rent-seekers as in: “While renewables may very well have a place in our future energy needs …”.

    • Well, as a free-marketer myself, I think this goes along the lines of “a free-marketer will sell you the rope you use to hang him”.

      That, or they sniff profit in having the government confiscate money from everyone, then dish it out to well-connected free-marketers in the name of saving the planet.

  27. It looks like Nick Stokes and Griff are vying for the Monty Python Black Knight award – although I’d say that Nick has won it hands down.

  28. As much as I was ready to blame it all on wind power projects here, I feel that the evidence is not quite there yet. I read the report – Four wind farms failed at 16:18:09, and two at 16:18:15, six seconds later. Why did they fail in groups all at once (to the second) if a wind gust caused them to spin too fast and therefore shut down? I guess I can believe it could happen due to the way the wind farms are interconnected, but I would have to hear that from an expert in transmission and/or someone familiar with how this particular system was connected. It seems equally plausible at this point that the wind farms could have been tripped out due to the instability that happened externally to them (the downing of three pylons nearby). I will wait for the final report.

    That being said, doesn’t this situation do a wonderful job of highlighting that when 48% of your power comes from wind, you have a problem. Forget about the downed pylons for a second. The storm could have shut down all the wind farms within a few minutes, which would have overloaded and tripped the interconnector from Victoria all the same.

    Thus, regardless of whether or not it did this time, the AEMO (and every other jurisdiction) must now realize that it could happen again, solely because of the prevalence of wind farms vs. other sources of power.

    • Forget the overspeed shut down theory – it didn’t happen.

      The blackout was caused by lack of system stability. Firstly in that the wind turbines themselves are not hugely stable so that the short circuits from the fallen towers were enough to trip them off the grid. Secondly, they do not contribute to the stability of the grid because they operate asynchronously (like the inverters for PV) so when the wind farms tripped as reported, the remaining wind farms did not help the grid stay up to give the grid operators enough time to load shed (selective blackouts).

      Instead, they had just 7 seconds from the first wind farms to go offline and one second from the 2nd set of wind farms going offline before the whole grid blacked out. Synchronous generators of the same capacity as the lost wind farms would not have tripped in the first place. Synchronous generators of the same capacity as the remaining wind farms would have kept the grid stable long enough for controlled islanding.

  29. Wind generation using massive windmills is erratic, unreliable, difficult to manage, ugly as sin to look at (Freudian towers waving mechanical arms are not a turn on, at least not to me!), and they kill wildlife. They also have subtle effects on susceptible (acid-loving) plants as calcium diffuses out of their foundations. And they are so expensive they need subsidies, both for construction and in operation. Subsidies are a regressive tax on others so impact negatively on the economy, especially the poor. Wind generation also makes the grid, which operates perfectly well with other forms of generation, very difficult to manage. Nor are their decommissioning costs built to their costings, as is required with mining and nuclear. How are their owners going to get rid of the massive concrete foundation blocks? Just leaving them to pollute well into the future (concrete does break down) is not acceptable since most natural ecosystems in Australia are sensitive to disturbances and are delicate.

    Nor are they carbon neutral. Not only are great amounts of carbon dioxide produced during their construction, they also have a subtle but real effect in reducing wind speed which reduces the rate of supply of that essential nutrient for photosynthesis, carbon dioxide (yes Greenies, it is an essential nutrient, not a pollutant) thus lowering the photosynthetic rate (although this last is speculation at present although there is evidence based on the massive increase in crops that we are now obtaining worldwide due to the increase in CO2 in the atmosphere with a very welcome large reduction in the price of food).
    The obvious solution for Australia is to go nuclear as this is cheap, reliable and safe, although the initial costs are high. The output from nuclear generators can be rapidly adjusted to meet fluctuating demand. And Aus has a lot of suitable raw materials: yellow cake and the even more abundant thorium.

    And, perhaps best of all, high or no winds do not affect nuclear plants.

    Now, if only we could harness the hot air emitted by the protagonists for wind generation.

    • The coal industry also requires heavy subsidies, estimated at 3/4 trillion USD annually worldwide.Coal mining alone is responsible for tens of thousands of human fatalities, and that is before the stuff is even burnt.Coal power stations also emit more radioactive material directly into the atmoshpere that that consumed by the entire neuclear power industry, as most coal is tainted with various radioactive isotopes.

  30. Thinking about the headline:

    “Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings”

    It seems to me that this is a case of blaming the last straw for breaking the camels back and ignoring the cinder blocks it was loaded up with. If the wind had gone offline first, and the grid had stayed up till the pylons went down, would that prove it was the fault of the pylons going down that caused the blackout, not the wind farms disconnecting?

    Right now, the logic seems to be that because the wind going off line was the last thing that happened before the inter connector was taken off line, that it is to blame for the whole thing. It isn’t that simple.

  31. I take from the report only that an extensive series of failures of no specified nature caused the disconnection of 315mw of wind generation.So this still leaves the question of whether it was a failure of transmission infrastructure, rather than anything to do with wind turbines themselves.Interesting to note that at the time half of the states power was coming from wind turbines which supposedly don’t work in high winds.

    • Dan,
      there is an engineering limit after which the turbines shut down to protect themselves.
      there also a number of other shut down criteria because they are non synchronous, a transmission fault on the line can meet these criteria.

      it is not clear to me what fault condition occurred when the turbines turned off.

      It is entirely predictable that during high wind events that the turbines produce more power, coal / gas backs off because wind takes priority, leaving the mix of wind as a % high during storms etc. Thus when a turbine comes off line during a storm, the impact is much larger.

  32. The issues are a natural consequence of the design and operation of the grid.

    Wind / Solar are prioritized above coal / gas.
    During a storm, solar would naturally go to about zero.
    During a storm, winds speeds would go up, ergo the capacity of the wind farms go up.
    During a storm, it is likely that wind / rain / lighting will take out power poles / lines.

    Non synchronous supplies can not handle voltage fluctuations etc, triggered by the storm and the low voltage conditions.

    Wind turbines also have an upper limit then they are turned off to protect them. Not sure if this was the case or not here as the fault conditions were not specified.

    In any case when there are storms, there is a good chance that the wind power will be disrupted.

    The power plant in VIC is not a swift gas turbine and can not handle this sudden change. So any time there is a decent storm, there is a reasonable chance of this happening in SA.

    SA needs to have spinning reserve during storm season in state, if this is not practical, shut the wind down and run the state from the interconnector. The grid as it is currently designed and operated can not handle rapid changes in electrical supply.

    This is entirely predictable and a natural consequence of have a large penetration of non-synchronous supplies that are intermittent.

  33. I still think the headline needs changing.

    “Australian Energy Market Operator report says wind farms were the ultimate cause of blackout, network withstood pylon downings”

    They didn’t say that.

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