On the AEMO page “Energy Updates and Media Releases” where you access their various reports post the 28 Sep blackout there is text summarising each link.
The link for – Updated 29 Sep 2016 – Media Statement 3 – South Australia Update 10:30 am – includes the following. “Initial investigations have identified the root cause of the event is likely to be the multiple loss of 275 kilovolt (kV) power lines during severe storm activity in the state.”
However that statement or claim is not found or repeated in the 5 Oct update(current at 3 Oct) see Exec. Summary on pdf page 5/31.
“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.” So by 3 Oct the loss of transmission lines was not front and centre as in the statement on 29 Sep.
The 5 Oct AEMO report also has this text in para 3.2 on pdf page 16/31 headed “Network damage resulting from the storm” and mentioning the loss of 22 transmission towers.
“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.” So towers fell after the blackout!
This statement buried deep in the update also is a backing away from the original “…root cause of the event…” putting blame for the blackout on falling towers.
The next update was on 19 Oct with data current as at 11 Oct.
In this Exec. Summary on pdf pages 5 & 6/31 there is no mention of falling transmission towers. The picture is one of multiple faults where wind farms cut out after not “riding through” voltage disturbances.
In my opinion AEMO should add a dated proviso or addendum to its webpage link text “Updated 29 Sep 2016 – Media Statement 3” – correcting or elaborating on their “…root cause of the event…” statement.
I think Australian taxpayers deserve the most accurate information possible from the experts they pay so well.
You picked a serendipidous day getting in ahead of the Third AEMO report into the Blackout.
www.aemo.com.au/Media-Centre/AEMO-publishes-preliminary-recommendations-following-the-South-Australian-state-wide-power-outage
I see the ABC; Renewable energy mix played role in SA blackout, third AEMO report confirms www.abc.net.au/news/2016-12-12/renewable-energy-mix-played-role-in-sa-blackout/8111184
is playing a bit fast & loose with the record in claiming “Previous reports confirmed a series of tornadoes severed high-voltage power lines, setting off a catastrophic chain of faults…”
Facts are AEMO has run hot on 29 Sept, undecided on 5 Oct, cold on the idea on 19 Oct & hot again today on claiming the downing of towers caused the whole blackout.
“Facts are AEMO has run hot on 29 Sept, undecided on 5 Oct, cold on the idea on 19 Oct & hot again today on claiming the downing of towers caused the whole blackout” [Beachgirl]
Despicable, of course, but truthful consistency is not a characteristic much valued by authority.
The catastrophic loss of power occurred *before* the pylons came down. Virtue signalling won’t change that, but unhappily our civilised power grids (one of the 20th century’s greatest advancements) will continue to be destroyed by such pious virtue.
Another two reports yesterday by AEMO
New Era For Transmission Planning In National Electricity Market -The Australian Energy Market Operator’s (AEMO) 2016 National Transmission Network Development Plan (NTNDP) illustrates the need for transmission networks to evolve to maintain a reliable, secure power system for the future.
www.aemo.com.au/Media-Centre/New-Era-For-Transmission-Planning-In-National-Electricity-Market
AEMO’s Chair Dr Tony Marxsen provided the keynote address at today’s CEDA event, addressing the audience on “Energy security and the reliability in the NEM”.
www.aemo.com.au/Media-Centre/Energy-security-and-the-reliability-in-the-NEM
I am yet to look at in detail. I would rather AEMO just administered the grid – they have two recent glaring fails in this regard –
[1] not paying more heed to BoM storm warnings prior the 28 Sep Blackout.
[2] AEMO was not aware that some wind farms may not be capable of riding through multiple successive faults on the network.
IMHO ideally AEMO should leave other issues like long term planning up to other orgs. The entire forward planning of “renewables” is so fraught with green and renewables spruikers lies the grid Admin should just do their best in day to day running the grid as safe & cheap as possible.
Media Statement 3 states :-
1. REPORT OBJECTIVES AND SCOPE
This report, the third in a series, sets out AEMO’s understanding of the following, at this stage of its investigation:
Details of the Black System event and its causation chain.
_______________________________
I draw your attention to ‘causation chain’. My preferred version of that is ‘cascade failure’. To understand the blackout, you have to understand :
Power Grid – Cascade Failure and Spinning Reserve :
Key Phrases :
en.wikipedia.org/wiki/Cascading_failure
A cascading failure is a failure in a system of interconnected parts in which the failure of a part can trigger the failure of successive parts.
en.wikipedia.org/wiki/Operating_reserve
In electricity networks, the operating reserve is the generating capacity available to the system operator within a short interval of time to meet demand in case a generator goes down or there is another disruption to the supply.
Cascade Events :
On the evidence currently available, the cascade failure on 28th September 2016 followed this sequence :-
1: a storm which …
2: contained tornadoes which …
3: caused voltage disturbances on and/or damage to grid circuits which …
4: caused wind turbines to trip which ..
5: caused the Heywood interconnector to trip which …
6: caused a high RoCoF event on the islanded SA grid which …
7: caused the UFLS(Under Frequency Load Shedding) in SA to fail to operate which …
8: caused all connected generation in SA to trip at 47Hz falling which …
9: caused a blackout throughout SA.
From 2: to 9: is a cascade failure. All of 2: to 8: are the cause of 9:. If any one of 2: to 8: had not happened, then neither would 9: have happened. The real system failures were in 5:, 6: and 7:.
Let’s take your points one at a time Paul:
1. Yes a storm but not by any means involving record wind speeds.
2. Two an assertion without evidence, high wind but twisters don’t think so?
3. Yes grid disturbances which protection and auto-load shedding should have managed.
4. Yes and no, some wind turbines shut down due to excessive wind speed, others shut down because of consecutive grid disturbances that they should have ridden through.
5. The Heywood transmission circuits shut down because they were overloaded as a result of defective operation of the SA grid i.e. failure of a number of wind farms to ride through repeated grid disturbances as they should have (all connected gas generators remained operating) and failure of SA auto-load shedding protection to operate as it should have to recover a rapidly falling grid frequency. In short the Heywood interconnector protected the rest of the eastern grid from what could have become a massive system black, all down to the irresponsibility of the SA government’s “hippy grid”.
6. SA grid didn’t island because the SA auto-load shedding didn’t work.
7. Again SA auto-load shedding did not work as it should have hence no island.
8. and 9. Well yes, but by then the battle was well-and-truly lost because of two major maloperations (item 4) failure of wind farms to ride through as they should have, compounded by (item 7) failure of auto-load shedding to restore the system frequency as it should have done.