Yes. Basslink was finally repaired and made operational a few months ago. Although with the amount of rain they've had, they are probably self supporting on hydro at the moment.

Depends on how the infrastructure is designed. Also, it isn't isolated by people - it's done by automatics. When large isolations occur, sudden changes in demand can cause upline ripples. These become bigger and bigger as more load is shed, causing things like the heavily protected interconnector to self isolate.

Eyre peninsula, now powered, is still only just hanging on via one transmission line. They had a blackout for over two days because all three transmission systems were wiped out. They had to repair one temporarily, isolate the other two, and then slowly bring it online.

The transmissions towers are made to withstand a 1 in 100 year event. This means FNQ infrastructure is much stronger, to withstand cyclone force winds. Do people expect every building and structure in the south if the country should be built to cyclone standards? That would be unnecessarily expensive.

And during my time as an electrician none of them supplied Whyalla. It's electrical supply came from a BHP power house (steam turbines) which was fuelled by gases from the blast furnace.

Geez megan you are going back a bit now. I also worked at BHP and while you are correct,that was until the steel rolling mills were built in the early 60s. ETSA power was then required as the blast furnace powerhouse could no longer supply all of the plant and the town. I remember the towers being built from pt Augusta well. A second line was added later and I think extended at that time all the way down to pt Lincoln which had a diesel run powerhouse for its supplies and then got decommissioned as it was too expensive to run with the oil shocks of the 70s. Memory is getting faded so may be a little out. I am assuming BHP or Arrium as it is now called decommissioned its powerhouse in later years going on there concerns of no power with this outage.

Going on memory.

Blast furnaces produce a LOT of carbon monoxide which must be burnt to carbon dioxide to avoid poisoning the workers around - generally this is done in an associated power station.

Highest priority use is providing air for the blast furnace (the blast bit).

There is generally more than enough power for a complete steelworks and considerable export but initial rolling of slabs can be tricky re phase etc so better to have the power station connected to a larger grid. Other high loadings are starting big electric motors eg fan motors for blast, sinter plant suction etc.

Reckon you would be right there too. I recall having to take a canary with us when working near the top of the blast furnaces and if it fell over you had to fit your gas mask quick and get out of there. The intial rolling mill billet stand motors were 15,000hp DC English Electric motors (for speed control)via rows of contactors and resistor banks. You would walk inside them when carring out maintenance like changing brushes. I assume it is all done by AC motors via invertors now,but this was in the day before heavy duty electronics.

mostlytossas, perhaps I know you. Was an apprentice at the time and involved with a Swiss engineer installing new control panels in the power house. Then went to the steel works for the last period of construction, and stayed for commissioning, and early days of production on maintenance. Then went to ship construction/fitting out wharf and left mid 66.

I also recall something called a Ward Lennon set. This on memory was 2 AC motors at each end driving a DC generator to produce the DC supply to run the above motors. Im starting to have nightmares about it all.

Megan, sorry but I started there in 68.

The SA experiment shows us that beyond 15% renewable inputs develops an instability in maintaining synchronous 50hz power. Fact, just before the failure 960Mw of power was generated by the various wind turbine sites. Whatever caused the shutdown there was still over 500Mw on the interconnector lines...they were still operational...they did not collapse or lose a tower. The footage on TV only shows dinki 72 or 134Kv distribution lines not the big 300Kv monsters. When the review comes out, my bet is on a distribution Lin going down BUT the damage caused when over 900Mw of wind power dropped off line causing the brown out cascade shutdown of the entire system. There was not enough synchronous generating capacity close enough to even attempt to take up enough load to allow safe load shedding to keep the system alive...This was a BLACK shutdown! Ask any engineer how bloody hard it is to bring the entire network back online without sizeable generation assets. Wind will not even connect with being able to sense a load. Same with solar.

Note, SA is now functioning. This negates the idea of a main 300Kv transmission line coming down. 21 towers repaired in 5 days? And bring the network up to synchronous power across the state? Wait for the report and watch who does the government bidding. Wind power is not base load power.

Want to make the system work? Hook all that wind power up to pumped storage hydro. Regardless of pumping losses from "free" power, this will be the only way demand power could be made available from windfall generation

Best thing about SA: they never fall over and never catch fire!

"I also recall something called a Ward Lennon set."

I'd be thinking Ward Leonard named after the inventor? It's basically an electro mechanical device to control the speed of a DC motor.

(Off topic: The RAAF single seat Mirages had one on the back of the Cyrano radar to control the DC drive motors that controlled the radar antenna scanning. I'm not sure that I understood how that worked then and certainly not now.) :confused:

From the AEMO report this morning:
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.

A ‘Black System’ start is a pre-defined and practised plan which was activated following assessment of the electricity system and public and employee safety.
At 17:23, AEMO directed the SA transmission network owner ElectraNet to progressively energise the main Victorian interconnector through to Adelaide to start Torrens Island Power Station and provide a basis to allow customer supply to be restored.Restoration of electricity supply started in Adelaide at 19:00. By midnight on Wednesday 28 September 2016, 80–90% of electricity (that could be restored) was restored.
The remaining electricity load could not be restored, as the loss of three of the four 275 kV transmission lines north of Adelaide, together with the unknown status of the fourth line (which required physical inspection), effectively cut the SA transmission grid in two, isolating the north of the state.
In accordance with standard industry practices to protect public safety and the safety of ElectraNet’s field crews, the transmission lines north of the Adelaide metropolitan area could not be re-energised before visual inspection on the morning of Thursday 29 September 2016. Continued poor weather conditions and high winds kept helicopters grounded, making slower ground patrols of the transmission network necessary.
The northern line confirmed intact was re-energised at 12:15 on Thursday 29 September 2016, allowing some electricity to be restored in the northern region.
Supply to the three large industrial sites in the north of the state remains constrained due to the limitations which remain in the northern region.
At 21:00 on Friday 30 September 2016, the last remaining segment of transmission supply, the southern Eyre Peninsula, was restored.
Temporary transmission tower structures owned by ElectraNet have been deployed, and also contributed by network owners in other states to assist in the restoration. Access continues to be hindered by poor weather conditions and flooding. Consequently, the restoration of the second and third lines is expected to take 7–10 days.
On Thursday 29 September 2016, pursuant to clause 3.14.3 (2) of the National Electricity Rules (Rules), AEMO was directed to suspend the market in the SA National Electricity Market region by Ministerial direction by the South Australian Government under the Essential Service Act 1981.
The SA wholesale electricity market remains suspended and prices continue to be determined in accordance with schedules and processes defined in the Rules.

The props stopped and the power went off... The question is, had a power station been supplying that 315mw of power, would it have disconnected? And putting all your eggs in the Haywood connector basket is obviously a dumb idea. Get your act together, you crow-eaters!

The media is now reporting that Electra Net, operator of the high voltage transmission infrastructure has had to install a "kill switch" to isolate the Prominent Hill mine, Olympic Dam and Roxby Downs. Apparently with the withdrawal of Port Augusta power station, reliance was placed totally on the interconnector, and at times of low wind and moderate to high power demand the system is unable to cope. More telling, is that they say no credible consideration was ever given to the limitations those factors imposed.

In today's news the Whyalla steelworks have lost confidence in the states ability to supply power, and are in talks to generate their own power using waste process gases and natural gas. To get through the troubles they have sourced generators from WA, Q'land and NSW.

Way to go SA. :{

The hypocrisy of using the interconnector, which is powered by Victorian coal, beggars belief... If Weatherill had any morals at all, he'd demand the power coming through that be clean. If he wants 40% of his power to be clean, the he can generate the dirty 60% himself.

The hypocrisy continues...

Can't guarantee you power ourselves, sorry, but we'll give you some money so you can put in a gas power station...

And to think the idiot running our state (Vic) is sending us down the same path. Despite the overwhelming evidence SCREAMING at him that the power supply in SA is a shambles, he's going to adopt the same ludicrous mantra. We want to be 'clean & green' as well. That's more important than providing reliable power to keep industry ticking over, and lighting/heating etc to the masses!! :ugh:


Sheer folly to think that wind & solar alone is a viable alternative.


After he decimates the Latrobe Valley, we won't be able to power our own state let alone provide a back-up to SA. Its looking like not just industry that will be needing a back-up generator. I can see it now, every house in the street with a back-up generator chugging away in the evening, so they can cook their dinner, and watch the nightly news, with the premier crapping on about how he's saving the planet from all those dirty coal-fired power stations he's shutting down, while the rumble of the generators and the smell of the diesel fumes continue into the night.... :D


Meanwhile, in India & China, as they build another couple of hundred new coal-fired power stations to supply cheap & reliable power to their booming economies, what must they be thinking when they see us shutting ours down, leaving the resource we are fortunate to have, buried in the ground, and going with an alternative that is much more expensive and a lot less reliable. :ugh: :ugh:


As my grandfather used to say.. 'Wake up Australia'..!! http://cdn.pprune.org/images/smilies/boohoo.gif

Well, the answer is yes.
"but at 16:18, following an extensive number of faults in a short period, 315 MW of wind generation disconnected" is lawyer speak for the lines fell down and the power went off.

But if you want more detail it's in the report, the timeline (P10) is clear

16:18:08 (T-8s) Single-phase-to-ground fault on Davenport – Belalie 275 kV line.
16:18:09 (T-7s) 123 MW reduction in output from North Brown Hill Wind Farm, Bluff Wind Farm, Hallett WindFarm, and Hallett Hill Wind Farm.

[The Bluff and North Brown Hill WFs are connected to Davenport-Belalie line and they tripped one second after the line went down]


16:18:13 (T-3s) Single-phase-to-ground fault on Davenport – Mt Lock 275 kV line
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.

[Hornsdale is connected to Mt Lock-Davenport line and it tripped 2.1 seconds after the line went down.]

No generator (of whatever type) would have been able to export as there were no lines left to export down.
---------
Then the interconnector tripped as it was carrying its full load to start with (a decision made well before time by AEMO who thought that the likelihood of this type of event happening was "not credible")

Then the frequency swung at about 6Hz/sec which is about twice the "safe" rate as decided by AEMO about 10 years ago and now set in the protection of all the generators in the national market. IE there isn't a power station in Australia that would have stayed on under those conditions.

Certifs

They don't call him D*ckhead Dan for nothing!

This thread is interesting in that there are a lot of electrically savvy pilots commenting on it. It would seem that, as tradies go, electricians turn into pilots more than say plumbers, builders or mechanics. Or perhaps vice versa? I gained my electrical qualifications well after becoming a commercial pilot to supplement poor GA pay.

Is there a correlation between an interest in flying and an interest in electrons?

Is it folly, or are we just seeing teething problems in the transition (from coal to renewable)? Is expecting a 100% reliable grid 100% of the time optimistic? I would tend to think so.