The future of energy generation and storage

[sptrawler]

Thinking about all this, I think the biggest issue isn’t coal versus solar or that certain power stations are gradually falling in a heap but politics.

It’s not necessarily a question of what Australia’s policy is going to be but when, or perhaps even if, we’re going to have one at all.

I won’t be surprised if one consequence of this week’s goings on in federal politics is that in practice it’s now up to the states and that’s it.

In that context it’s anyone’s guess what’s going to be done physically.

It’s hard to see the private sector investing amidst all the uncertainty and at this point I wouldn’t be betting on government investing either until such time as the situation is clarified.

My apologies smurph, your posts are much appreciated, one too many reds last night.

 

[Smurf1976]

My apologies smurph, your posts are much appreciated, one too many reds last night.

All good.

For the info of all, there has just been a significant power system incident affecting Qld, NSW, Vic and SA (noting that the ACT is part of NSW in this context)

At 13:12 today, so about an hour ago:

*Qld electrically separated from the rest of the system. In layman's terms that means power stopped flowing between Qld and NSW.

*SA electrically separated from the rest of the system. So power stopped flowing between SA and Vic.

At the time this occurred power flow was from Qld to NSW and from SA to Vic.

Transmission between Tas and Vic (flow being Tas to Vic) and between Vic and NSW (flow being Vic to NSW) remained in operation.

As a consequence 800 MW, or about 10% of all load in the state, was shed (turned off) in NSW and for Victoria the figure was 280 MW or about 6% of load in that state.

In layman's terms this was a "near miss" serious incident and not at all good. Had it happened at a time when load was higher, so that is either hot or cold weather, the effects could very easily have been an order of magnitude worse in terms of the consequences.

 

[Smurf1976]

a decade is practically nothing in utilities right?

Very true.

Coal, oil, gas you’re looking at 40 - 50 years of useful life.

For hydro it’ll keep going so long as it’s properly maintained. Eg Lake Margaret power station is 104 years old, still runs base load today, and is by no means worn out although it did need a new pipeline and a bit of concrete works a decade ago.

Tarraleah is 80 years old, also still running base load, and the only reason replacement is being considered is that it would make sense to double or more the size and turn it into a peak load operation to help support intermittent renewables natuonally. If it wasn’t for that aspect then it could simply be maintained as is (indeed that option hasn’t been ruled out).

Batteries are very short lived by comparison.

 

[SirRumpole]

In layman's terms this was a "near miss" serious incident and not at all good. Had it happened at a time when load was higher, so that is either hot or cold weather, the effects could very easily have been an order of magnitude worse in terms of the consequences.

Do we know why this happened ?

 

[Smurf1976]

Do we know why this happened ?

It's one of those things where AEMO will need to (and no doubt will) examine all recorded data closely to work out exactly what happened.

What can be said though is that 3 transmission lines tripped in NSW, two of which which are parallel to the same places.

Things like SA disconnecting from Vic would be a consequence of that. That is one of those things that ideally wouldn't have happened but it has always been the case, anywhere, that power systems are a bit like a whole lot of dominoes standing on end. Once one thing fails it quite often will in practice take something else down with it. That is not itself an unusual scenario - one generating unit tripping will sometimes take out another one. One transmission line tripping can do likewise. Once you get a system disturbance the risk that something else also fails becomes dramatically higher.

In a robust system where there's always enough spare capacity to cover the loss of the two largest generators or a transmission line trip that's really just a nuisance. Trouble is, those sort of buffers have been considerably eroded and there are situations now where such a buffer simply isn't available (though that wasn't a problem today) and it's under those conditions where "one domino fell over and knocked another one over with some minor consequences" as happened today changes to "one fell and before we knew it the whole lot were down" as famously occurred in SA and has also happened in other places previously.

 

[SirRumpole]

Thanks Smurf .

 

[sptrawler]

All good.

For the info of all, there has just been a significant power system incident affecting Qld, NSW, Vic and SA (noting that the ACT is part of NSW in this context)

At 13:12 today, so about an hour ago:

*Qld electrically separated from the rest of the system. In layman's terms that means power stopped flowing between Qld and NSW.

*SA electrically separated from the rest of the system. So power stopped flowing between SA and Vic.

Smurph, when this happens, one assumes S.A is running very high renewable generation, how does the system cope with the VARs?
Do they have large static Var reactors installed? The system configuration has changed so much, with the closing of Power Stations like Port Augusta, I was wondering if it has changed the Var control in any way.
I suppose they can remotely control the tx taps, but I would have thought it must cause some weird swings, with the high reliance on renewables.

 

[Smurf1976]

Smurph, when this happens, one assumes S.A is running very high renewable generation, how does the system cope with the VARs?

Exactly how it's set up in SA isn't something I know about in sufficient detail to comment but one thing is that renewable generation was pretty low at the time (purely coincidental).

Some observations (following figures are all for SA only). There's unavoidably a lot of numbers here.

Note: Osborne and Pelican Point are separate combined cycle gas turbine power stations located in suburban Adelaide. Torrens Island B is a steam turbine power station with gas-fired boilers also located in Adelaide. These 3 plants were all fully operational, though not actually running at full capacity, during the incident. Other gas and diesel plant in SA was offline at the time due to not being needed.

Prior to the incident:

Demand: 734 MW (excluding rooftop solar)
Intermittent renewables generation: 215 MW
Osborne, Pelican Point and Torrens Island B power stations combined: 808 MW
Battery charging at 37.1 MW

Immediately after the incident:

Demand: 784 MW (excluding rooftop solar)
Intermittent renewables generation: 140 MW
Osborne, Pelican Point and Torrens Island B power stations combined: 654 MW
Battery charging at 39.5 MW

So the effect of the incident in SA was:

Reduced intermittent renewable generation from 215 MW to 140 MW. No problem that's an expected response.

Reduced thermal generation from 808 MW to 654 MW with all units at the power stations in operation reducing output. No problem that's an expected response.

Battery was already charging so couldn't do much. Presumably the 39.5MW was the maximum it could take if already almost full so it couldn't really do anything to help.

Demand went up 50 MW or 6.8%

Now it is pure speculation on my part but I'm assuming that 50 MW of small scale private generation, which would be rooftop solar in practice, was knocked offline by the system disturbance and resultant frequency increase. Either that or perhaps clouds swept across Adelaide at the same time by pure coincidence (not joking there, it's at least possible). Something happened at that time and suffice to say that one thing power system disturbances don't normally cause is a sudden rise in demand.

If that is the case, if small solar systems reduced output in practice, then they helped stabilise the system within SA which is a desirable outcome under the circumstances.

Following all this, and noting that the cause was the loss of 2 transmission lines between NSW and Qld, AEMO has imposed an operating constraint to limit power flows on those lines to a level at which simultaneous loss of both lines would be manageable without a repeat of today's drama. That limitation causes other issues so isn't a long term option but it's a workable and sensible measure in the short term given that whilst the lines are back in service, the underlying cause of the fault is not known.

In layman's terms that means they reset it, it works, there's uncertainty as to exactly what happened so they'll limit power flow to a level that won't really matter if it fails until the answers are determined. Then fix whatever the underlying cause was, then go back to operating at full capacity.

 

[SirRumpole]

Ian Verrender on the power crisis.

http://www.abc.net.au/news/2018-08-...-fall-guy-in-the-national-power-play/10166882

 

[sptrawler]

Ian Verrender on the power crisis.

http://www.abc.net.au/news/2018-08-...-fall-guy-in-the-national-power-play/10166882

He sums it up pretty accurately, it doesn't change the problem, renewables at this point can't replace the coal and it is shutting down or breaking down.
There will be a major shortage, unless someone comes up with a viable solution, no one has yet.
He is only saying what smurph has been saying, shame Verrender can't articulate the severity of the problem, instead of repeating what is already known. IMO

 

[Tisme]

He sums it up pretty accurately, it doesn't change the problem, renewables at this point can't replace the coal and it is shutting down or breaking down.
There will be a major shortage, unless someone comes up with a viable solution, no one has yet.
He is only saying what smurph has been saying, shame Verrender can't articulate the severity of the problem, instead of repeating what is already known. IMO

Be interesting to see what the cost implications are going to be when the renewable machinery like turbines, bearings, glass, etc need replacing

 

[SirRumpole]

He sums it up pretty accurately, it doesn't change the problem, renewables at this point can't replace the coal and it is shutting down or breaking down.

Well the point is do you replace obsolete coal power stations with more coal or something else ?

CCGT stations with a sensible domestic gas reservation policy would be the most cost efficient way to go imo.

They take much less time to build than coal, can be ramped up and down faster, and generate less emissions, so why not ?

 

[sptrawler]

Well the point is do you replace obsolete coal power stations with more coal or something else ?

CCGT stations with a sensible domestic gas reservation policy would be the most cost efficient way to go imo.

They take much less time to build than coal, can be ramped up and down faster, and generate less emissions, so why not ?

Because I didn't think there was enough gas to go around over east. If there is plenty of gas I would say combined cycle is the way to go 55% efficiency, even HEGT's are good these days, around 40%. The only downside is GT's require rebuilding much more often than steam sets, due to high inlet temps, other than that they are great units, we have a couple of CCGT and HEGT's at Kwinana.
Like I said from what I've been reading on here and in the media, there isn't enough gas, allocated. Obviously if you're going to replace 10- 15,000MW of coal with gas, you are talking serious amounts of gas.

 

[SirRumpole]

Like I said from what I've been reading on here and in the media, there isn't enough gas, allocated. Obviously if you're going to replace 10- 15,000MW of coal with gas, you are talking serious amounts of gas.

That is why the need for a gas reservation policy that cuts into current contracts if necessary.

Just because gas companies over committed on exports doesn't mean that the local market has to go short.

 

[sptrawler]

That is why the need for a gas reservation policy that cuts into current contracts if necessary.

Just because gas companies over committed on exports doesn't mean that the local market has to go short.

And meanwhile the problem just keeps worsening.

 

[luutzu]

That is why the need for a gas reservation policy that cuts into current contracts if necessary.

Just because gas companies over committed on exports doesn't mean that the local market has to go short.

Santos calls it "energy security", for each state

Somehow they also get to not pay a royalty for the gas in QLD for 3,000 days.

Good thing every Australian is a shareholder so all Aussies gain... oh wait.

 

[sptrawler]

Santos calls it "energy security", for each state

Somehow they also get to not pay a royalty for the gas in QLD for 3,000 days.

Good thing every Australian is a shareholder so all Aussies gain... oh wait.

Well someone is going to get paid ship loads, to sort the problem out, sooner or later.

 

[luutzu]

Well someone is going to get paid ship loads, to sort the problem out, sooner or later.

For sure. Then somebody is going to get fired! (then be re-employed by some lobbyist)

 

[sptrawler]

I guess an election will bring about a decisive result, then the ball will be pushed into motion and the reality will be highlighted.
Then whoever is in Government will say, this is worse than we were led to believe and drastic action will be required. Unfortunately we will have to put our initial policies in abeyance, until a later date, when we have over come this dire situation.

 

[Smurf1976]

Something I will note is that when I first posted on this forum about Australia’s looming energy problems, the Prime Minister’s name was John Howard.

Since then it has gone from a problem on the horizon to one bashing on the front door and no government, of either persuasion, has sensibly addressed it.

It’ll take the lights actually going out in NSW or Vic to bring about change.