Approaching the tipping point

As the capacity of coal power sinks towards the level of demand

This is a short story to explain why intermittent inputs from the sun and wind can’t power a sustainable energy system.

Spoiler: Its all about the wind droughts. Especially at night.

First, three important features of the power supply and what that means.

  1. Input to the grid must continuously match the demand
  2. The continuity of RE is broken on nights with little or no wind.
  3. There is no large-scale storage to bridge the gaps.

Conclusion. The transition to wind and solar power can’t proceed with current storage technology.

Second, wind droughts happen.

Most people assume that the wind is always blowing somewhere not far away and we are assured of that by windpower enthusiasts. Australia is supposed to have wonderful wind resources, and wonderful solar resources as well.

We certainly have wonderful wind watchers, led by Anton Lang and Paul Miskell and his helpers. Over a decade ago they sounded the alarm on periods of very low wind across the whole of SE Australia that can last for days.

They showed the way and now anyone can monitor the wind power supply day and night, minute by minute, drawing on the cornucopia of information available from AEMO, The Australian Energy Market Operator. The suite of resources available for wind-watchers is itemised in the second part of this briefing note from The Energy Realists of Australia. All of the briefing notes are available here.

For example, look at the NemWatch widget provided by the great RE supporters at Global Roam. The two peak periods of demand for power are breakfast and dinnertime so we can look at the widget at sunrise and sunset to see how the system performs when there is little or no sun at all, and often enough very little wind.

The picture below was taken at dinnertime, just before solar power faded out for the day.


Sometimes there are several periods of severe wind drought in quick succession. June 2020 was the worst case in recent times, before that June 2017 had a 74-hour period of drought with several shorter episodes.

The most serious episode in very recent memory was a spell of 40 hours in August 2022.

Below is a highly simplified picture of the way we are approaching a critical tipping point in the power supply as conventional power capacity (mostly coal) has run down since the turn of the century. Up to the closure of Hazelwood in 2017 there was enough spare capacity to buffer the effect of unplanned outages and the peaks of demand at dinnertime during very hot and very cold weather.

Meanwhile the penetration of wind and solar power rose from zero to reach 36% of demand last month. The expectation is that coal will continue to exit the system and RE will continue to rise.

Demand varies in a predictable way over 24 hours, with a small peak at breakfast time and a larger peak in the evening, just as the sun is fading away. Hence the first pinchpoint in supply comes at the evening peak.

That happened during a heatwave in 2019 and there were rolling blackouts in some parts of Melbourne but otherwise a combination of mild summers and load shedding kept the grid up until the drama in June last year.

If coal continues to exit then the time will come when the supply of conventional power is short of the base load, the lowest level of power that is required day and night. Then the proverbial will hit the fan every time the wind slackens to a point where it cannot make up the difference between the downward sloping line of conventional power and the horizontal line representing demand.

The RE enthusiasts expect that increasing the capacity of wind and solar will ensure that the gap is closed but on windless nights there nothing to fill the gap. Heroic load shedding (widespread rolling blackouts) will be required to maintain the integrity of the core of the grid and avert a system black.

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July 11, 2023 4:50 pm

In all honestly, the sooner we start experiencing problems the better – it will mean we’re not as far down the road to complete ruin.

Pat Mac
Pat Mac
July 11, 2023 6:43 pm

Even though we have rooftop solar panels, I shudder to think what our next bill will be.
We have shots between $15 credit and $235 debit on our last two bills.

Subsidies from the palace chook have been at play here, but what for the future?

July 12, 2023 7:05 am

More like a “tripping point”.

July 12, 2023 7:46 am

This series of slides supports a talk “How wind droughts can destroy Western civilization.”

I think you mean Western society. Western civilisation has already been destroyed by the prog-left march through the insitutions.

That being said, academics from the University of Melbourne, University of QLD & Princeton have issued a report saying nuclear is too expensive and too slow in development to contribute to Australia’s net zero by 2050 emissions target.

However, they also concede there are “too many uncertainties to map a single path to net zero” and call for more government intervention to make it happen.

Truly, only academics could be this stupid.

Rod Stuart
Rod Stuart
July 12, 2023 7:54 am

Something you don’t mention is the problem with black start capability.
Windmills and solar panels must synch to something.
If the rotating equipment on the grid has fallen over, a reasonably large unit somewhere must be started. Large units don’t generally start up on a dead bus.
IN the event of a blackout, is there sufficient black start capability available?

July 12, 2023 8:29 am

NO ONE , but No One human on this GOD’s Earth can change Mother Nature.

July 12, 2023 10:10 am

I’m with duncanm @4:50.
Bring on the blackouts, the mayhem, the outcry.
Only when the apathetic public start experiencing the results of what they have been voting for for years will change possibly occur.
Who knows, maybe even “their ABC” will awaken from their cultish beliefs.

PS…only kidding about their ABC. They are all too stupid and too far down the rabbit hole to admit they were ALWAYS wrong!

July 12, 2023 11:38 am

The Chris Bowens of this world will always have access to (diesel) powered electrical generation in order that their “important “ work not be impeded. The plebs on the other hand will just have to suck it up. A significant percentage of Australians will go along with this.

July 12, 2023 12:20 pm

Labor Blackout Bowen & Albosleezy along with the Greens aiming to destroy Australia

Australia, Germany merging into ‘green energy superpower’: Bowen

Energy Minister Chris Bowen says the government is working towards exporting Australian green hydrogen to Germany as the largest European economy seeks to reduce its carbon emissions.

Bowen said Germany’s interest in Australia’s burgeoning green hydrogen industry was “a very strong feature” of Prime Minister Anthony Albanese’s visit to Berlin ahead of the NATO summit this week.

“I spoke to the prime minister yesterday from Berlin and he told me how much Australia’s Hydrogen Headstart project had been noticed in Germany,” Bowen told ABC’s RN Breakfast.

Bowen said it was “extraordinary” that Australia and Germany had announced joint funding for green hydrogen projects in the Illawarra, Queensland and South Australia earlier this year.

“The German government is investing in Australian green hydrogen because they want to see us, like we do, merge as a green energy superpower because they know they can’t generate the energy they need … as the industrial powerhouse of Europe,” he said.

Questioned about Australia’s move to join the G7-backed “climate club”, Bowen said it indicated the country was no longer a “pariah” when it came to international discussions about climate change.

“I wouldn’t overstate this, but nevertheless, it’s an indication that Australia is back at the top table of international discussions on climate.”

Bowen hits back over battery pork barrelling claims

Labor has hit back at claims its community batteries program represents sports rorts-style pork barrelling, claiming crossbench MP Rebekha Sharkie has spread “erroneous” information about the $200 million program.

Ms Sharkie this week hit out at announcements included in Labor’s first two rounds of the Community Batteries for Household Solar program, asking Auditor-General Grant Hehir to investigate whether Labor targeted seats it hoped to win at the 2022 election.

Documents released under freedom of information showed about 40 per cent of the battery grants went to marginal electorates, with more than 30 per cent going to Labor-held seats.

Department officials said the choice of the 58 suburbs for the first two rounds of funding had been decided by the Labor Party before the election.

More than 400 batteries are planned and applications for the next round are open for assessment by the Australian Renewable Energy Agency, an independent body tasked with managing the government’s renewable energy programs.

The Australian National Audit Office has included the battery grants program in its list of potential audits for 2023-24.

Climate Change and Energy Minister Chris Bowen wrote to Ms Sharkie on Tuesday, asking the Mayo MP to correct claims she had made in media interviews, including with The Australian Financial Review.

“In March 2021, the then-opposition announced that a Labor government would invest $200 million to install 400 community batteries across Australia. This was based on evidence at the time that one in five households had rooftop solar, but only one in 60 had storage due to the high upfront costs of household batteries.

“As you are well aware, the opposition of the day is not able to access departmental advice or resources. This is in stark contrast to sports rorts, where the then government received and ignored public service advice,” he said.

The sports rorts saga led to the resignation of then sports minister Bridget McKenzie, after it was revealed the Morrison government had used a colour-coded spreadsheet to award $100 million in controversial local grants.

Senator McKenzie resigned from cabinet and from her party leadership positions after a report found she had breached the ministerial code of conduct.

Ms Sharkie said Labor had run “a Clayton’s grants round” for the battery program.

“What I would like to see is the auditor-general to look at the mechanics of the program,” she said this week.

“When I look at where they were selected, they were largely either Labor seats, or marginal seats, many of which have now fallen to Labor.”

Mr Bowen said geographic and demographic diversity were considered, including to ensure areas with sunnier and wealthier conditions did not benefit disproportionately.

“The 58 pre-election locations were chosen based on need,” he wrote. “This included areas with high solar take up but low battery take up, as well as areas with high numbers of renters and apartment dwellers who are locked out of rooftop solar but can draw from a shared battery.”

Last month, the National Audit Office found the Morrison government deliberately breached federal grant rules in its management of a $2 billion program for local health services, exceeding legal authority and failing ethical standards.

July 12, 2023 4:54 pm

Rod Stuart
Jul 12, 2023 7:54 AM

Rod nails it.
Asynchronous low-inertia inverter-based generators cannot restart a grid from a system black event.
Remove enough heavy rotating generators and the grid will go down during a night time wind drought and stay down permanently.
Most people who rely on town water will be dead in four days.

Mate, how about adding a line to slide one…
“Renewables cannot restart a blacked out electricity grid.”

another ian
another ian
July 13, 2023 8:40 am

IMO – an addition for the last graph –

In the space between the head of the red arrow and the end of the bottom curve there needs to be a proclamation that

“Here a miracle occurs”

In the spirit of

comment image&f=1&nofb=1&ipt=5e92eb66425911c4241a89b42b3d763f3e7ecbe5ca8d8bdc41540889f3a76b50&ipo=images

July 13, 2023 10:31 am

“IN the event of a blackout, is there sufficient black start capability available?”

Snowy hydro could do it – 5-6GW available IIRC (max).
You don’t get much bigger than hydro generators in terms of rotating mass!

Boambee John
Boambee John
July 13, 2023 11:55 am


A small glimmer of hope.

As long as the rains that fall actually fill the dams, rather than being diverted to those so precious “environmental flows”.

July 13, 2023 6:17 pm

Calling them ‘renewables’ is gaslighting, but the term seems here to stay, unfortunately.

I’d prefer ‘intermittents’.

Similarly, ‘fossil fuels’ has an old-and-stale connotation. They’re carbon-based energy and not a bad thing, dammit!

July 14, 2023 12:26 pm


A small glimmer of hope.”

Yes John.

Also, while Eraring stays “open”, there are at least 2 gas turbines there that can be started from batteries, and can supply enough power to start a coal unit.
Hell, even Warragamba is supposed to provide enough to black-start NSW, although it likely is now neglected and wouldn’t be able to.

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