when liddell and the rest start shutting i can only assume that a black hole may be left, i can only imagine that governments will be climbing over each to lock in further supply and throw money at producers..... just like sth oz has been doing.
Where the difficulty lies on the purely physical side of it is volatility.
Eg on the 24th and 25th of January this year there was forced load shedding in Victoria.
Well, OK, technically it was voluntary on the 24th but only because industry said they'd do it before AEMO formally gave the orders but that's dealing with semantics really since there was no choice but to turn some load off.
On the 25th it was forced via blackouts to homes and small businesses etc. Those who'd done it the night before were still stabilising their production process so simply couldn't put their hand up gain no matter how much money anyone offered.
So load shedding on the evening of the 24th and around midday on the 25th.
But if you'd taken a look around Victoria's power stations in the early hours of the 25th then you'd have found quite a few completely silent. Shut down and doing nothing as there was simply no need.
That level of volatility on the physical supply side is inherent to electricity but doesn't really happen in any other commodity industry. You don't have for example a wheat shortage at midday then a glut later that same day, every other commodity moves far more slowly than electricity does.
Spot price is likewise. Just because it went from around $100 all the way up to $14,000 at 7pm doesn't mean it won't be down below $50 well before midnight. So again that's extreme volatility compared to other industries.
Then there's the project life cycle and this is where the big problem lies in the immediate term:
2019 - New power station at Barker Inlet (SA) adds 210 MW and mothballing of Torrens Island Power Station (TIPS) A units 1& 2 removes 240 MW so no real change.
2020 - Mothballing of TIPS A unit 3 removes another 120 MW.
2021 - Mothballing of final TIPS A unit removes another 120 MW.
2022 - Permanent closure of Liddell (NSW) removes 1680 MW.
Then there's things like a recent incident. I won't go into details, to my knowledge there's no official public release of the information, but suffice to say there's been an incident at a power station and several hundred MW won't be running for quite some time. Best estimates at this stage are ~ 4 months to return to service but that's subject to change. It's pure good luck that it didn't happen a few months earlier and that there will
probably be sufficient supply available from other sources to cope without it until it's back in service.
Now the point there is that any "good" option from a longer term perspective has the problem that it would be extremely difficult to get it built in time and for some of them it's just not going to happen.
Of the things which could be built in that time, they have the problem of being higher cost than the other options in an environment where that cost can't realistically be passed through to consumers. They can be done physically but cost is the problem.
Extending the life of Liddell seems too difficult politically. It's probably the most well known power station in the country for all the wrong reasons so don't go there. It is also by far the least reliable power station in the NEM by the way - the outage rate is
extremely high compared to anything else.
So what happens?
The new NSW - SA line should be built by 2022 indeed I'll speculate that nothing will stop that. That helps to the extent that SA and NSW don't usually experience high demand at the exact same time.
A few open cycle gas turbines, diesel engines and medium size batteries will likely appear somewhere.
Politically far easier than extending the operation of Liddell would be to keep TIPS A running a bit longer. It's far smaller but still enough to be of use (480 MW versus 1680 MW) and has the advantage that whilst very much outdated (in operation since 1967) it does work fairly reliably (it's orders of magnitude less trouble than Liddell) and the big one is that it's not the subject of any political debates. Keep that going along with more transmission and a few batteries or diesels etc and we'd likely scrape by. If there's no gas to run it then fear not - Torrens Island also has the ability to fire oil which isn't cheap but it's a workaround if needed.
Note that the last two paragraphs are speculation on my part and aren't something actually proposed by anyone, at least not at present.
As for Liddell, well if it makes it through to 2022 then it's going to be like the marathon runner who collapses to the ground with one hand across the finish line......
The mistake in all of this in my view is that the wrong plants were closed. Wallerawang (NSW, 1000 MW), Northern (SA, 546 MW) and Redbank (NSW, 150 MW) were between them the same size as Liddell and in vastly better condition. Returning Redbank to service wouldn't be impossible but that's only 150 MW and the other two are too far gone - literally blown up with explosives in the case of Northern.
Anglesea (Vic, 160 MW) was small and getting old but also another one that's gone (and been blown up) but which worked far more reliably than Liddell.