Essay by Eric Worrall
A new study suggests blackouts will only happen sometimes, if we build enough batteries and overcapacity, and a hydrogen export industry.
What is ‘dunkelflaute’? And how will a new long-duration battery change Australia’s energy grid?
Limondale project designed to store excess renewable power during day and dispatch when demand is highPetra Stock Mon 29 Sep 2025 10.00 AEST
Australia’s longest duration battery will come online this year, a major milestone as the power grid charges towards a mostly renewable energy future.
When fully charged, the Limondale battery in south-west New South Wales will be able to pump 50MW of power back into the grid over eight hours.
…
What is ‘dunkelflaute’ and can we avoid it?
Seasonal, or deep storage (beyond 12 hours), is more like an insurance policy, a strategic reserve for managing rare but unpredictable periods when cloudy and still weather conditions persist over several days.
The phenomenon known as “dunkelflaute” (dark doldrums) is specific to highly renewable grids.
“That’s the bit that is hardest to solve,” Reeve says.
In Australia this risk is low and it can be minimised by the geographic spread of solar, wind and hydro generation, or managed with seasonal storage like pumped hydro, like Snowy 2.0.
…
Read more: https://www.theguardian.com/environment/2025/sep/29/limondale-long-duration-battery-energy-storage-system-bess-what-is-dunkelflaute-energy-grid-nsw-australia
The study which claims the risk of prolonged blackouts is low is model based, they attempt to infer real historical conditions by hind casting based on scraps of historical data.
Quantifying the risk of renewable energy droughts in Australia’s National Electricity Market (NEM) using MERRA-2 weather data☆
Joel Gilmore, Tim Nelson, Tahlia Nolan,
Abstract
It is anticipated that Australia’s National Electricity Market (NEM) will be almost entirely dependent upon variable renewable energy (VRE) production in the coming decades. The Australian Energy Market Operator (AEMO) and other researchers have provided detailed forecasts of the storage and firming required to ensure a secure electricity system that is supplied exclusively by VRE. However, these forecasts utilise existing VRE datasets which are often limited by historical observation given the relatively recent deployment of renewables in the Australian electricity system. This article seeks to significantly expand this analysis by building a VRE output forecast model that utilises 42 years of real-world weather data. This ‘backcasting’ approach provides data that will allow planners to far more accurately determine firming and storage requirements to overcome real-world instantaneous and medium-term production risk in a system supplied entirely by VRE resources. Our results can be used by policy makers to better plan the just transition to a renewable energy-based electricity system.
Read more: https://www.sciencedirect.com/science/article/pii/S0313592625001134
From the body of the study, “… The end goal is a consistent weather dataset with much higher spatial resolution than can be obtained from only physical historical measurements. …”.
The authors claim a high degree of accuracy, and also claim their model avoids overfitting. The following shows one of their model back casts vs real world data.
Personally I have my doubts. Overfitting is an insidious problem with these kinds of back casting attempts, especially when you are dealing with inadequate historical data. Even if you try to keep a portion of the data isolated to test the skill of a model trained on the rest of the data, knowledge of how to overfit that allegedly isolated test data can leak into your model through repeated attempts to get the model right.
The conclusion of the study is interesting;
Through the MERRA-2 reanalysis dataset, we have undertaken a calibrated backcast of the existing VRE fleet as well as a hypothetical Future NEM fleet with greater geographical distribution. While the concept of energy droughts have received much attention, we do not find evidence of extended time periods of low VRE production in the NEM. For example, over a two-week period in the worst historical time sequence, the VRE fleet would still have delivered 70 % of the expected output once seasonal trends (e.g., winter solar production) are taken into account. A 30 % reduction in expected energy is therefore the worst two-week historical VRE drought on record.
…
Firstly, it highlights the amount of firming required. For example, consider the simplest case of flat demand across the year, and the VRE fleet were built such that average generation equalled average demand. Section 4.2 suggests the worst case firming energy requirements would be equal to i) two-thirds of the daily average energy demand; and ii) one-third of average monthly energy demand. This firming could be delivered through conventional hydro, seasonal energy storage, or zero emissions gas peaking units but “overbuilding” the renewable energy fleet (that is, allowing for some spilled energy over time) is also likely to be an efficient source of energy firming. The relatively flat production risk over periods longer than two weeks (Fig. 15) means technologies that can deliver additional energy over longer periods will be favoured (i.e., building additional VRE capacity and fuel based technologies such as zero emission OCGTs). A highly flexible demand side (e.g., hydrogen export industry) will support additional VRE build and provide its own source of firming.
…
Read more: https://www.sciencedirect.com/science/article/pii/S0313592625001134
See – we Aussies can have our glorious renewable future, all we need is to put up with a few more blackouts, create a hydrogen export industry nobody wants, build lots of renewable overcapacity, and provide just over a week (a third of a month) of firming backup capacity, either through gas plants which will sit idle and burn money most of the time, or through lots of batteries.
Looming over all this is the energy surge the AI age is already starting to demand – a possible doubling of current electricity demand by 2050, just through the growth of AI.
Of course for a fraction of the money required to ensure a week of battery backup and 2-3x renewable overcapacity we could refurbish all our coal plants and have near zero blackouts, and not have to bet the farm on a hydrogen export business which does not exist, but that kind of thinking is obviously evil and wrong.
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The sun does not shine at night. There are periods of littler to no wind across the entire Australian continent. Batteries go flat when needed most.
South Australia produced 72% of its energy from wind and solar in the past 12 months. However there has nbeen no reduction in the peak demand for disputable generation in the State.
I run an off-grid solar/battery system at 37S. It has been in operation since 2012. Once set up with a design CF of 3.8% and battery of 50 hours supply of average load, it went three years before the battery went low and I had to revert to grid power. It did another 3 or 4 years before battery went low again. However over the past few years, the battery has gone low almost every year. The battery capacity has not reduced because I have lower the cut out voltage to maintain working capacity as the battery has aged. There is a Biot more shading from a large tree.
Counting on weather to run an essential service will result in deaths. Australia recently lost people with a telephone outage. Imagine when the whole east coast goes dark.
“distributable” generstion instead of “disputable” generation?
Actually dispatchable. I do not know what I type to end up with autocorrect disputable.
F——-g autouncorrect is what I call it.
The auto-correct gods know better than you do about what you should have typed.
Correction of typing is incomplete until the happy day when AI type “its” that is not altered to “it’s”. Apostrophes matter, OK?
Geoff S
And when like just now, when I type “I” unaltered to “AI”.
Geoff S
Kind of like AI. If you do not complete your own thoughts when typing, and REVIEW your typing prior to ‘posting’… why post?
What about disreputable generation?
Now I’m sorry I mentioned it 🙂
Thanks for your input. I notice that we all tend to use the metric of household usage when discussing power requirements here in Australia. Can I ask everyone to think in terms of industry requirements? What are our industry needs should be on our minds. Case study – Aluminum smelters running from renewables and batteries – is this really possible? Industry = jobs.
“new study suggests blackouts will only happen sometimes”
Er, did they miss the Iberian blackout and the 11 deaths in goldilocks weather? Surely not? They seem to believe that occasional blackouts are, well, acceptable.
“the risk of prolonged blackouts is low”
What is defined as prolonged? Is it half an hour, an hour, ten hours? The Iberian blackout took ten hours before power was restored. I’d say being stuck in a lift (elevator), or on a train in the middle of nowhere etc etc for ten hours is prolonged.
The Iberian grid was already in a weakened state, owing to insufficient synchronous generation and excessive reliance on inverter-based renewables. The system failed to withstand a fault that originated with a single solar inverter. This was not an unavoidable technical event – it was the result of systemic underestimation of voltage control risks, poor compliance enforcement, and REE’s failure to schedule or deploy sufficient dynamic voltage support. – Kathryn Porter
Never has so much utter bolleaux threatened the lives of so many.
There have been blackout in the US NE that lasted 26 hours.
Extremely prolonged.
It was great fun for us. I was attending boarding school in eastern Massacusetts. When the lights went out in town, we switched the power for our library over to power essential services in town.
Even if the “low” risk could even be calculated… what is that “low”?
The whole renewables plan is a huge pile of dunkenflaute if you ask me.
Oz has centuries worth of good coal that could supply reliable, cheap electricity for everyone there if rational thinking could be applied.
Poor fella my country indeed.
The renewable plan is designed to fail.
An integral feature with the aim to deindustrialise..
And this study only exists for propaganda reasons.
Already now renewables are having serious problems but it is managable as there is enough traditional energy to cover up the performance gaps of renewables.
Imagine this trash energy without fossil and nuclear backup.A total disaster.
Just another communist utopia promise that will turn into the exact opposite.
If the guy/s behind this would be held accountable and had a serious price pay (health,wealth,lifes) for being wrong they would have never released this crap.
There is also another interesting thing:
For this system to work you won’t have control over your battery,
as they will have access to it whenever they want to.
And the permanent additional drain will destroy the battery very fast.
Read The Population Bomb and you will be reading the manual they use.
Fabian Society.
Just read what’s written on the Georgia Guidestones.
Population reduction down to 500 million.
And those ” stones ” were massive and very expensive.
To be able to produce and pay them and set them up without leaving a trace of its origin you need to be very wealthy.
Wealthy as the eugenists like Carnegie and Rockefeller who actually financed the Hitler – Rudin eugenics program.(they also delivered the fuel additives for the Nazi war planes: No additives = no planes = no world war possible, especially when your enemies have planes)
Australia has current Federal law prohibiting electricity generated by nuclear. A few years ago, this happened when our government agreed to this banning to get greens to agree to another matter. This spur if the moment throw-away has zero place in future legislation because it was unforeseen, never put before we voters and has severe detrimental economic consequences.
We sceptics are commonly castigated for our remarks, but who could support blame for this disgraceful act of political incompetence? Geoff S
Erm, are they saying what I think they’re saying?
What I think they’re saying is that if we forget about actually measuring stuff, and just substitute whatever numbers they’ve plucked out of thin air, that’s somehow more accurate.
Is that what they’re saying? Am I missing something?
Yep, they’re suggesting after training their model on picket fences they can predict the entire picket fence from a couple of pieces of wood.
I see that Rio Tinto has decided to close its huge coal power station at Gladstone, which supports an aluminium smelter, alumina refineries, plus a huge coal terminal. Too costly, they are going with renewables. Not a decision they would make lightly – they have much skin in the game.
Nick, g’day mate.
Can we count you in for accepting the occasional blackout? Perhaps you already have a patented Griff generator for your own energy needs?
You told me not so long ago that the UK economy was powering forward. I’m guessing you modelled that…
“UK economy was powering forward” ….. towards oblivion !!
Funny how Nick makes these pronouncements and then vanishes into the ether.
Never answers. That is the hallmark of the flaky minded.
“ether”?
Well, sleep. I made te comment at 8.10pm local time. But there is nothing of substance to answer to do with Rio closing its plant.
Except that it is not closing its plant !
”
More like fishing for Government funding to keep it open for even longer..
Even the Government must realise they cannot afford to lose that much dispatchable generation..
Even when caught out in a lie/misstatement, Nick doubles down on the mendacity.
Boyne smelter will now only operate feeding off government support. Once the support stops, the smelter will close. It is no longer economic.
The same with Tomago and it looks like NSW government is not going to come to the party so it will close.
Australia is heading toward running off rooftops and household batteries with all heavy industry gone and grid scale solar and wind stranded assets.
Grid solar in South Australia has already lost its market to rooftops and wind is having to wind back when the sun shines.
The only way to recover from this mess is to upgrade existing coal fired power stations and treat electricity supply as an essentiual service rather than a craps shoot.
Nick also quoted complete bullshit they aren’t going to renewables they have existing contracts with 6 other power stations likely because they don’t trust the aging power station.
Everyone is telling coal plant owners all the plants have to close Nick, even comparatively conservative governments like Queensland. Promising a hostile regulatory environment is not exactly an incentive to invest.
Nick consistently ignores the impact of government on people’s decision making process.
Premier Steven Miles emphasised: “This is a good deal for Queensland that secures one of our biggest employers, but also one of our biggest emitters.”
Under the agreement, Rio Tinto must:
The federal government later announced a $1.7 billion production credit scheme for low-carbon aluminium, providing additional support for the industry’s clean energy shift.
From Colitco.com/bold mine.
Maybe I missed something in the linked piece? I can’t see where RT says that it is either retiring the plant because of cost, or that they are going with (cheaper) renewables. The plant seems to be Australia’s oldest coal plant, due for closure in 2035, and they are now considering bringing that date forward. And also apparently looking at extending its life.
How you run smelters etc on intermittent power, if that is really what they are planning, is an interesting question. I know even less about this than I know about Gladstone, Australia, which is close to nothing, so it would be nice to have an account of how exactly this is done.
Inquiring minds want to know!
Well, here is the Murdoch version:
“The mining giant reportedly has been looking to sell its 42 per cent stake in the coal-fired power station after it secured renewable energy deals that would supply about 80 per cent of the needs for its Boyne aluminium smelter but only 30 per cent of its firming requirements.
“Between now and March 2029, the JV participants will engage with stakeholders on the energy market and on options for the future use of the site, which will inform the timeline and strategy for retirement of the facility,” the statement read.“
If it relies on “secured renewable energy deals”
It will close very soon . !
There is no such thing as “secure renewable energy” (except perhaps hydro)
It’s industry code speak for gas power stations. You pretend it’s renewable energy backed by a gas generator only the renewables run at 20% and you claim the renewables will all be fixed by 2050. Everyone pulling the fraud will be long since retired by then.
So no, they have not “decided to” close it, that is just the way the far-left press in interpreting it.
They have just notified the Government that they “might” ! 😉
A great ploy, putting the Qld government on notice.. 🙂
Maybe it will wake them up to the reality that they NEED the reliability of coal fired power.
Maybe even get a nice subsidy/grant to keep it open.. 🙂
“which has operated since 1976″
So that’s, like, 50 years… nearly..
Wind and solar will need “renewing” at least twice over 50 years.
With increased cost, waste, manufacturing pollution and environmental damage each time.
Not to mention the massive landfill requirements for all the garbage produced at disposal time.
Anyone with a coal or gas power plant that’s aging would be extremely sensible to get rid of it as quickly and cheaply as possible. The fact that Renewable Energy production is so variable and unreliable means that they need a substantial amount of idle backup. Idle backup isn’t actually productive, and just wastes an enormous amount of money in order to prop up the ‘free’ wind and solar generation.
Because it is not profitable, the government will have to in some regulatory manner force reliable power plants to sit idle until required by unreliable power generation. That’s a quick route to business failure. Anyone honest in the energy industry can see this in Australia right now. They’re either getting out of coal and gas generators (because they will be very costly because of regulatory requirements), or out of Australia entirely.
Nick seems to believe that if a fossil fuel plants isn’t actively burning fuel, then there are no costs involved.
I see 🦄🦄🦄🦄🦄…
As usual, Nick assumes that government taxes, regulations and mandates have no impact on anyone’s decision making process.
If they have to pay full price for renewables- without any subsidies and tax breaks, will they still switch?
Wrong.
“Rio Tinto said in a statement no final decision had been made and there was potential to extend the power station’s life.”
Rio is just angling to be holding ALL the cards when the realisation hits governments that wind, solar & batteries are an embarrassing fizzer, and the people still want their reliable electricity from somewhere.
Well, they have notified their workers. The (conservative) Qld Energy Minister said:
“Queensland Energy Minister David Janetzki said the state government was preparing for the closure.
“Rio Tinto has for some time been working on a plan for the closure of the oldest coal-fired power station in the country,” he said.
“The Crisafulli government has been actively working with our government-owned corporations to prepare the network for the eventual closure of Gladstone Power Station.“
And now the owners are squeezing the government….
… shopping for a grant to keep it open longer… just like in NSW. 😉
It’s funny Nick can’t see the games being played to get the tax payer money.
It’s hard to see what one does not want to see.
If they are like most companies, they have plans for pretty much all contingencies. The fact that one of those possible contingencies is the plant shutting down does not prove that they have decided to close the plant.
What is it about alarmists and their inability to admit when they have made a mistake.
So what?
Like corporations’ actions are supposed to make any sense at all. Can you say Mary Barra?
Their decision was obviously made “Light-headedly”.
Q) Exactly How Hostile is Australia when it comes to using Coal to generate electricity?
Try as they might, they can’t “fix” Ruinables, because they are fundamentally, fatally flawed to begin with.
They can’t seem to fix “models” either.
Does anyone believe for one moment this “study” would have seen the light of day if the “model” said there was a high risk of frequent and extended blackouts?!
Most alarmists don’t, or can’t realize how complex models are. The other day nyolci declared that if they can model orbital mechanics, they should have no trouble modeling the climate.
I do not believe nyolci has any real experience with models, simulations, or emulations.
The first rule in assessing a model is to challenge all assumptions.
Airfix?
It’s funny how ignorance flaunting seems to be endemic among alarmists.
ED MILIBAND V ELON MUSK
Completely off topic —
Nick’s mention of the power station in Gladstone reminded me of a poem.. Presumably the place was named after Gladstone the British 19c Prime Minister. Anyway, here is the poem which starts out by mentioning him:
Yeux Glauques
Gladstone was still respected,
When John Ruskin produced
‘King’s Treasuries’; Swinburne
And Rossetti still abused.
Foetid Buchanan lifted up his voice
When that faun’s head of hers
Became a pastime for
Painters and adulterers.
The Burne-Jones cartoons
Have preserved her eyes;
Still, at the Tate, they teach
Cophetua to rhapsodize;
Thin like brook-water,
With a vacant gaze.
The English Rubaiyat was still-born
In those days.
The thin, clear gaze, the same
Still darts out faun-like from the half-ruin’d face,
Questing and passive. . . .
;Ah, poor Jenny’s case’ . . .
Bewildered that a world
Shows no surprise
At her last maquero’s
Adulteries.
Yes, Gladstone was still respected. Before researchers had discovered he had made the mistake of including some previous slave owners among his ancestors. Time to change the name.
Forget the notion of reparations. Britain spent huge amounts in lives, resources and money through the Anglo-Ashanti wars and the West Africa Squadron.
If anything, they owe us…
Indeed yes. And in addition to abolishing the trans-Atlantic trade, getting the European powers to agree to let it intercept ships registered with them, the country did its best to wipe out the trans Saharan slave trade – often not mentioned in accounts of slavery – and one for which it had never had any historical responsibility.
Its not an exaggeration to say that the British in the 19C did everything any one country could do both to eliminate slavery in all its possessions, and to eliminate the slave trade, and it was successful.
If reparations to Africa are owed by anyone its by the Arab states of the Gulf. The trans-Saharan trade lasted from the 7th century till the late nineteenth and even 20C in some places. The numbers were huge and the death rate from transit overland, and from the male genital mutilation that was practiced on the way, were enormous.
The real blind spot – the supply of slaves to the islamic world.
In terms of guilt one need only look at the methods and results of colonisation in North America (mainly English, some French) and Meso/South America – Portugal and Spain.
And we’re the bad guys.
The left tends to assume that those they hate today have always been evil, and those they favor today, have never been evil.
And much like Big Brother, they have to adjust the facts of history to support whatever is being taught today.
The US paid it’s reparations in a terribly bloody Civil War-700,000+ dead, and much more wounded and morphine addicted. . You Brits paid your share, we paid ours-and still the greedy btards want something for nothing.
Fundamentally, even the Arabs were not the main source of slaving.
They just glommed on to the established practices of the African tribes to take and trade slaves.
The Arabs and others took advantage and expanded a well-established supply & demand marketplace.
So if “blame / responsibility” for slave taking and trading is to be leveled at any particular party, it would be the ancestral African tribal chiefs.
(But good luck squeezing any “reparations” from them, hey).
In NSW there is NEVER any “excess renewable power”.
Even on gorgeous sunny days like today, when no-one is using any heating or cooling, COAL still carried over 35% of the grid.
That means that all Limondale accomplishes while charging, is to allow the coal fired power to run a bit higher. !
Even with a perfect grid (power from anywhere could be sent everywhere without loss), there would still be conflicting energy requirements across the grid due to unpredictable demand. Add in grid losses, storage losses and reluctance to throttle back revenue producing sources, the supply-demand equation becomes unsolvable. Who is going to overbuild generation only to have it sit idle due to some bureaucratic regulator? Who will schedule maintenance? Who will repair bankrupt grid and power facilities? Who will pay for new capacity that will be used rarely, and where will it be located? It would be a bureaucrat’s delight, and an investor’s nightmare.
And a consumer’s nightmare.
Best buy stock in candles.
Overbuild. It’s cheaper to just curtail quite a lot of the time than to try to store. But one starts by overbuilding by a factor that is the inverse of annual average capacity factor. Overbuild more from there — by probably 6 times nameplate in total. Then further overbuilding comes with its own costs in terms of O&M, interest, taxes, spoiled landscapes, hazards to wildlife. Doesn’t even count the planned expansion of uses of electric power.
Then the storage: $1 per watt-hour capacity.
Australia is about the sunniest place on Earth, so that helps. I have a friend retired to St. George, UT area. Sunny place, too. He has spent $60,000 on solar panels and batteries to just get him through a night of air conditioning in the hot season. No spare power for any community services…
The interest earned on $60,000 would cover 1.5 times my combined electric and gas bill. No data so far on how often he will “repower” his system.
Am I right that your retired friend believes he’s coming out ahead?
Now, smarty pants authors, do a new analysis with another variable, destructive wind/rain events. Example, Australia’s well known cyclones. I survived a direct hit from one in 1956 and have been close to a few others. Cyclones have a fair probability of knocking out a windmills and wrecking a percentage of solar panels, the effects of which last orders if magnitude longer than the contribution of all those pathetic batteries.Other natural events like bad hailstorm smashing solar panels might also be added to models.
Face reality. Engineers who seek uninterrupted electrical delivery will not give more than a passing glance to papers modelling incomplete, optimistic what ifs.
Listen to President Trump. Renewables are so yesterday now. Geoff S
When the Limondale battery explodes, we will be able to see it from here.
and like earthquakes, it will be blamed on climate change
I don’t mean to be the fly in the ointment but isn’t Australia the world’s largest exporter of coal? Mostly to China.
So you build your green utopia, sarcasm on, with the cash you get from exporting coal.
Makes perfect sense.
Coal export is not a fly in the ointment…
… it is the elephant in the room. ! 😉
Australia’s absolute idiocy in not establishing clean new coal fired power stations has made them a laughing stock around the sane world.
Unless you understand the difference between power (KW) and energy (KW-hr), STFU!
Speaking to the the Stark person.
ROFLMAO
so it might keep 1/1000 of Australia going overnight when the wind isn’t blowing…
As I read here it is 8:45 am in the Pacific NW of the USA. That’s Idaho, Oregon, and Washington states. Wind energy dropped to zero in the last 2 hours. Back on the 25th there was a massive burst and that went to zero 30 hours later. It makes me think of a yo-yo.
A “hydrogen export industry” Is it April 1st?
Wouldn’t one need a substantial amount of unused power in order to create a hydrogen export industry?
From everything I’ve seen, they are still way short of providing enough power to meet the needs of their existing population.
In the land of Oz, you’re going to love all the back up batteries turning into toxic clouds and flaming biohazards. A couple of the Tesla megapacks recently let all their smoke out in Nevada.
Story Tip
https://hotair.com/tree-hugging-sister/2025/09/30/a-couple-of-tesla-mega-packs-ignited-at-a-co-solar-facility-last-week-n3807327
“Anticipate”… what a wonderful word.
“A 30 % reduction in expected energy is therefore the worst two-week historical VRE drought on record.” That number is inconsistent with what I would expect. More like only 30% available duriing the worst two weeks. This is the driver for dispatchable emissions free resources.
Yep, that fat tail is going to smack anyone who tries to act on this advice.
To get around a one in ten years run of 10 days at 70% power we would need about 2000 GWh of storage, call it 2 trillion dollars. They’ll need replacing every 15 years, meaning our children will be paying $133 M per year one way or another, in perpetuity. This is about double what the NDIS is predicted to cost in 2028.
The implications of the following quote are even more expensive (or inconvenient-power cuts)
However, this analysis (Section 4.3) shows that 1-in-20 or 1-in-40 year VRE droughts are possible, and it may not be prudent for private utilities to invest to cover these risks. Therefore, these periods would either require a suitably flexible demand side, or some additional energy reserves to be procured by governments on behalf of the community and energy users. This energy would need to be held in reserve out of the market, so as not to simply substitute for prudent utility hedging.
For a minute I thought I was reading one of Francis’ New York climate reports. Same claptrap New York spouts.
We already know the limited lifespan of renewable generation.
What is the projected lifespan of their latest battery?