Giving way at uncontrolled intersections

[FoxtrotGolfXray 5.0]

Originally Posted by Citroënbender

Daringly, to return to topic - are the outages so bad as possibly suggested yesterday evening?

My comments were primarily based upon Loy Yang A losing all four units. That, IIRC, is an unprecedented event for them (outside of commission testing), and I was working on the basis that it would take them days, if not a week or more, to get all four units back on line.

As of this morning, all four units are back online. A pretty massive effort to have them back less than 48 hours after the trip.

Originally Posted by whynot

That the faults bumped off major power stations nearby is no surprise. But one will have to wait for the engineering report to understand if it was transient stability, over frequency (due to lack of load) or under frequency (too much load dumped on them) that caused the generators to trip. All said, nice work by the plant operators to get back two units that evening - on a power station not designed for TTHL.

My understanding is that Loy Yang A is designed for TTHL. The problem in this event was that the boilers tripped before the turbines, I believe.

Hence my scepticism that they'd have all four units back on line in the time frame they did.

If anyone wants a good insight into the details of the events, this website provides some good data and interpretation.

https://wattclarity.com.au/

From a personal perspective, we lost power at my house at about 4:30pm (about the time the storm front hit town) and were without power for around 18 hours. Parts of town were also out, whilst some still had power. It also seems as though power was restored in stages, as my mum, who lives up the other end of town from me, lost power at the same time as I did, but had her power restored later that night.

We also lost all telecomms a couple of hours after power went out. I assume that is because tower back-up systems also ran out of juice. That was restored mid morning yesterday, around the same time as power was restored.

Some of my work colleagues who live around Yarram, Boolara, Mirboo North, are still without power and have indicated it will take some time to have it restored simply because of the amount of tress and wires down, etc.

[whynot]

Originally Posted by FoxtrotGolfXray 5.0

As of this morning, all four units are back online. A pretty massive effort to have them back less than 48 hours after the trip.

My understanding is that Loy Yang A is designed for TTHL. The problem in this event was that the boilers tripped before the turbines, I believe.

My mistake on Loy Yang not being designed for TTHL. I am getting my power stations mixed up. I have been there once in a professional capacity and it is an amazing site.

Regardless, designed for TTHL (or not), boiler trips are bad news. The crew on site did well to return the plant to service so quick.

Just to back up what you are saying, there is a SARS document on the AEMC web site that discusses some of the challenges with system restarting. It is a good read.

https://www.aemc.gov.au/sites/defaul...21-%282%29.PDF

We are certainly in an age where there are a lot of clueless folk, with little engineering understanding, in key positions demanding changes in the grid with little understanding of the consequences. Sigh ...

[Terraplainin']

Originally Posted by whynot

We are certainly in an age where there are a lot of clueless folk, with little engineering understanding, in key positions demanding changes in the grid with little understanding of the consequences.

This should be printed, in 40 point bold, in every newspaper in the land.