AEMO Climate Heresy: Ageing Coal Plants Necessary to Keep Costs Down

Guest essay by Eric Worrall

According to the Australian Energy Market Operator, a government body charged with managing the Australian electricity grid, Coal plants are vital to contain end user electricity costs.

Coal needed for decades to keep Australian power prices down: AEMO report

AAP, Claire Bickers, News Corp Australia Network
21 minutes ago

COAL-FIRED power will be needed for decades to come to keep power prices down and the lights on as the Australian energy market transitions to renewables, the Australian Energy Market Operator says.

In a report to be released today, the AEMO says extending the life of coal-fired power stations is the most viable way of keeping energy prices down as the transition takes place.

It also predicts replacing Australia’s existing coal-fired network would cost between $8 billion and $27 billion by the mid-2030s.

AEMO’s analysis says that based on the projected cost, the cheapest option would be to “retain existing resources for as long as they can be economically relied on”.

“Over the next 20 years, approximately 30 per cent of the NEM’s (National Electricity Market’s) existing coal resources will be approaching the end of their technical lives, and will likely be retired, which highlights the importance of mitigating premature retirements as these resources currently provide essential low-cost energy and system support services required for the safe and secure operation of the power system,” it says.

Meanwhile, a Newspoll conducted for The Australian has found voters believe the federal Coalition is best placed to keep power prices lower and maintain reliable energy supply.

The Turnbull government is leading Labor 40 per cent to 34 per cent on the question of which party had the better approach to energy.

This represents an eight-point turn around from a similar poll conducted in May when voters backed Labor on this issue.

Read more (paywalled): Weekly Times

What happened since May to create a surge in Australian voter support for fossil fuels? The answer of course is Winter. Large numbers of Australians have endured a series of cold fronts – not cold in US terms, but pretty cold for us sun loving Aussies.

As most people in Australia receive their power bills monthly or quarterly, I suspect many poll respondents have had an opportunity to notice a nasty upward spike in their home heating bills, and have responded by rapidly ditching their love of our renewable future in favour of demanding more affordable energy.

Update (EW): fixed a typo (h/t Marcus)
Update (EW): AEMO report available below.

Over the 20-year plan period, AEMO anticipates the retirement of a substantial portion of the NEM’s conventional generation fleet. A significant number of coal-fired generators in the NEM have either advised that they are closing or will reach the expected end of technical life in this plan period. Collectively, the generators expected to retire by 2040 produce around 70 terawatt hours (TWh), or 70,000 gigawatt hours (GWh), of energy each year. This is close to one-third of total NEM consumption. In addition to providing critical energy production and dispatchable power, conventional generators have also traditionally been relied on to provide essential grid security services, such as inertia, system strength, and frequency control.

To support an orderly transition, ISP analysis demonstrates that, based on projected cost, the least-cost transition plan is to retain existing resources for as long as they can be economically relied on. When these resources retire, the modelling shows that retiring coal plants can be most economically replaced with a portfolio of utility-scale renewable generation, storage, DER, flexible thermal capacity, and transmission.

Within the plan period, under AEMO’s Neutral ISP planning scenario, the analysis projects the lowest cost replacement (based on forecasted costs) for this retiring capacity and energy will be a portfolio of resources, including solar (28GW), wind (10.5 GW) and storage (17 GW and 90 GWh), complemented by 500 MW of flexible gas plant and transmission investment. This portfolio in total can produce 90 TWh (net) of energy per annum, more than offsetting the energy lost from retiring coal fired generation.

Read more: AEMO Report


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NW Sage

It seems that I remember many wise folks advising the Aussie ‘powers that be’ that it would NOT be cheap to replace coal with wind/solar and that the least expensive (and therefore most palatable way) would be to GRADUALLY replace the coal units as they wear out. I hate to say “I told you so” but it needs to be said sometime!
The folks that actually RUN the power grid are usually in the best position to weigh ALL the factors.


Why not really save some money by getting rid of grid wind and solar permanently….


There is no substitute for the base-load reliability of fossil fuels or nuclear. None.
No matter how gradual the phase-out of coal.
Best you get fracking Australia.

John of Cloverdale, WA, Australia

Don’t mention that f-word here. Otherwise, the unemployed, students and Trade union thugs will be out in the streets destroying everything in sight.


Sage , Marcus , Joel and John !!
John : I thought that the COLLECTIVE NOUN for this group :
” the unemployed, students and Trade union thugs”
( and assorted “greens” and OTHER eco-nuts and
“animal-rights-ahead-of-humans-types” )
which they left littered with their refuse and placards !!


pull your head in John!
theres a whole lot of landowners and others who do NOT agree with fracking.
especially when we DO have decent conventionally accessed resources and plenty of OFF shore options to use before we trash our farmland and wreck peoples incomes and land values with “good ole yankee know it all/.how”
you guys might need to do it as youve drilled n tapped the easier resources
we down under have NO such need, for the forseeable time.
and if you have to make 80$us per barrel to make it profitable…?
then with the aus dollar rate we’d be looking at over 100$ a barrel and thats outrageous when other sources can be bought for far less.


Ozspeaksup – Good news! Fracking doesn’t actually ‘trash our farmland and wreck peoples incomes and land values’.

Russ Wood

Whereas, in Australia, wind turbines actually DO trash all kinds of things. According to .

Sam Pyeatte

The illusion of cheap and reliable base-load power ever being provided by wind and solar will insure the long-term future of coal, oil, gas, and nuclear. Yes fracking will definitely be in the mix.

“Best you get fracking Australia.”

Rating the seven continents for photovoltaic resources, Australia probably nudges out even Africa as the best (the resource is closer to the likely consumer):

Best you get researching perovskite solar cells and solid state batteries, Australia


and if we’d spent what weve wasted on bloody wind n solar already???
we would have a couple or more, new, clean and reliable coal plants.
and thats not taking land mass used for solar and the upkeep of that n wind as well as what gets paid to select landowners for use/access.
smart meter cons alone have added near $80 a quarter to the service n supply charges in Victoria!

If renewables are really good for the planet, including economic development, why aren’t they capable of capital formation (making $), why haven’t they created jobs and why have they needed continuing governmental and political support for the last 40 years.

oh they have created jobs allright

But then so does employing people to dig holes in the road and fill them in again…

theres days prosperity means less work, more production.


Those who vote progressives into office for the ‘free’ phone won’t like it when they no longer can afford the energy that keeps them alive.
But they are so ignorant that they will blame capitalism for this. That’s why history is no longer taught in the ‘no’ education system.
Free stuff and Freedom are exactly the opposite.


Leo Smith and Robert….:
“oh they have created jobs alright…………..
But then so does employing people to dig holes in the road and fill them in again…”
“Another very different approach to welfare is a universal basic income (UBI). This would provide a guaranteed minimum income, regardless of whether someone works, and without eligibility tests……….”
Living wages and UBI are radically different ways of tackling poverty.
Work remains vital for a living wage, but is optional for a UBI.
A living wage would raise the value of paid work, but might make
life harder for some jobseekers whose labour becomes more expensive.
A UBI would provide income without work, which might encourage
more people to drop out of the labour force altogether.
I LOVE THE USE OF THE WORD “MIGHT” !( an optional extra perhaps ? )
I think it will “GUARANTEE” that MOST PEOPLE will DROP OUT
when you can “slack-off”and live just as well while on a
permanent holiday LIVING PARASITICALLY OFF your
fellow countrymen!?????
THESE are the SAME MINDS that think that FREE ENERGY is
( of course they WILL ALSO BE PROVIDED FREE and
REPLACED FREE every 15 to 20 years !! )


All those who promise Utopia create Hell.


Free stuff and poverty are counter parts within the same system of shared misery.



“and have responded by rapidly ditched their love of our renewable future”….ditching ?


“between $8 billion and $27 billion by the mid-2030s”……….

nothing like nailing the cost down

My thought exactly. With such a wide range, that doesn’t even qualify as a WAG.


That is the NPV cost to the economy. The actual system costs to replace the coal generators is many times that range. By 2030 they propose 90GWh of storage at $1,300/kWh. That alone is $113bn. But remember it has to be all done over within 15 years as that is their predicted battery life. I expect that will prove optimistic.

By 2030 AEMO forecast there will be around 30GWh of rooftop solar, 4 times more than now and 10.5GW of wind, twice what exists now. So these are all additional cost to replace three existing moderately sized power stations.

The AEMO report is a religious document. It makes constant reference to Climate Change and is based on the Finkel RET of 90% by 2050. It destines Australian industry to the scrap heap.

The power prices are so bad that our toilet paper manufacturer is going down the toilet:
In the near future Australia will need to import toilet paper!.

Bryan A

“Over the next 20 years, approximately 30 per cent of the NEM’s (National Electricity Market’s) existing coal resources will be approaching the end of their technical lives, and will likely be retired, which highlights the importance of mitigating premature retirements as these resources currently provide essential low-cost energy and system support services required for the safe and secure, RELIABLE operation of the power system,” it says
They forgot a very important word

J Mac

Solar and wind ‘renewables’ are not sustainable, in a cost competitive, no subsidies, fair trade energy market. Turnbull should cut the bull and just state the facts. For a nation as rich in coal resources as Australia is, failure to use those resources to cut energy costs and improve the lives of Australian citizens is dereliction of political and scientific duty.

Rob Leviston

So, Turnbull should cut the bull, and just Turn?

Patrick MJD

Turncoat is on the “make”, just like with Ozemail. Binning his shares just months before the collapse made him a millionaire.


A “transition” that will take a very long time. Time enough to develop better storage.


Time enough to find a new AFFORDABLE energy source !

Already got one.

People been told all to scary to deploy.

Why would anyone do that?

Good luck with that ‘better storage’ meme.

Best storage of all is a uranium nucleus. And guess what.

It is cheaps as chips and comes already charged up, and doesnt need complicated windmills and solar panels to do it.

Patrick MJD

It’s called Snowy Mountains 2.0. It’s a pump-storage project. Ya gotta laf…!

Rob Leviston

You are joshing, right? Storage is a net user of power, whichever way you slice and dice it! We have enough losses in the grid, due to long line runs, etc. Why introduce more losses through storage? No, the smart solution is to have a consistent, reliable, power source, that is available 24/7, no matter what the weather! And lets not forget, that just two years ago, Tassie basically ran out of water, and needed diesels to meet their power needs! If we end up in an extended drought, then Snowy 2.0 will be a dead duck.

” Tassie basically ran out of water, and needed diesels to meet their power needs.”
Tassie drained its dams to sell power to the mainland when prices were high, and gambled on rain. The diesel cost them, but they probably still came out ahead.

Storage losses look less painful when you aren’t paying for fuel.

Bryan A

AYUP, falls under the category of Miss-Management

Alan Tomalty

It looks like time for the nuclear option


Renewables bulllshittt artists from down-under . . .
“We’re getting out of coal”
We hope you don’t notice we’re spending 25-million moving a generator from Loy Yang A onto a cargo ship bound for Germany then back again to generate more evil coal-fired electricity.


Thanks for the links , Warren. I used to work at a site that had the Lampson mobile crane doing the heavy lifting. It was awesome to watch.


… pretty cold for us sun loving Aussies.

There’s a question of infrastructure. There’s a question of skills. Then there’s the question of what your body is acclimatized to.

I was raised in a very dry climate with extremes of hot and cold. My wife was raised in a much more humid climate which is where I’m now living. I suffer in the humidity. If it’s cold, I can’t get warm no matter how many sweaters I wear. If it’s hot, I hide directly in front of the air conditioner.

If it’s even slightly cold in Australia, I expect that people won’t have the wherewithal to deal with it. I also expect that someone stuck outside could experience hypothermia in conditions that a Northern Canadian would describe as sunbathing weather. It’s a joke. I’ve never seen anyone actually sunbathe in the arctic, just bask a bit in the sun in the lee of a building. 🙂

“If it’s even slightly cold in Australia”
We get the odd chilly morning, as we always have. That linked Daily Mail report is rubbish. “The mercury plummeted to -5C in Sydney and stayed below zero even after sunrise, “ The recent readings in Sydney are here. The coldest morning was 4.6°C. In fact, the coldest temperature ever in Sydney was 2.3°C.

Worth noting the maxima in that link too. 17, 18°C. We’re tough here – we can manage that.

Patrick MJD

“Nick Stokes

The coldest morning was 4.6°C. In fact, the coldest temperature ever in Sydney was 2.3°C.”

Where was the 4.6c measured and where was the 2.3c measured? Same site?


Patrick MJD

The Observatory site of the device MOVED. You should know that Nick.

It has moved a little, as stations often do. Statistics are here, and records go back to 1859. I was actually not quite right; lowest was 2.1°C in 1932.


coldest temperature ever in Sydney was 2.3°C.
Must have been the UHI at Sydney Airport, Nick. We had icicles in the suburbs in 1976.

Richard of NZ

About that time I remember crunchy grass on my way to work and that was Banksia.

Rob Leviston

I recall seeing those same figures, but they were talking about Canberra. I don’t think Sydney has been that cold!


+4.6°C (40°F) is plenty cold enough to be deadly.

Hypothermia is the number one killer of outdoor recreationists. Most cases occur between 30 to 50 degrees F. link Being tough can get you killed.

The actual AEMO report is here. It’s emphasis is rather different from what is reported here. It starts out:

“It is clear that the resources available to supply electricity in the NEM are undergoing a major transformation. These changes are evident across both the traditional ‘supply’ and ‘demand’ sides of the electricity market – and concurrently – with current and forecast retirement of conventional thermal generation as it reaches the end of its economic life, growing investment in grid-scale wind and solar generation, and a rapid uptake and increasing penetration of rooftop solar photovoltaic (PV) panels at household level.”

Another excerpt:

“Older baseload units find it increasingly difficult to compete in the current environment. These units have historically relied on relatively constant high production levels and stable revenues. In general, they are not well suited to respond to rapidly varying energy system needs. Their business model will be further challenged by increasing variability in the system and falling costs of competitive sources of energy, which in turn could lead to earlier than expected retirement. Further to this, the economics for investment are also changing. Investment in generating plant in energy-only markets depends on wholesale prices responding to reserve scarcity and exceeding new entrant costs. This is backed up by contract markets that reflect these underlying prices, but provide a stable revenue resource.

There is evidence from the last few years that the connection between reducing reserves, increasing wholesale spot prices, and additional supply is not being borne out in the NEM. The costs of variable renewable energy (VRE) and storage have fallen at an unprecedented rate and continue to fall. The business case for these assets relative to conventional generation continues to grow stronger, due to the combination of these cost decreases, relative risk profile, consumer preference, and government support. “

Didn’t Enron pioneer the Energy trading scam that we have to endure, despite the fact that Australians were overwhelmingly opposed to privatization of the public utilities in the first place, Nick?
In selling vital infrastructure to foreign entities, do we not also lose our sovereignty?
Was it not a French company that closed the formerly public Hazelwood plant?
Is artificial reduction of supply–Enron style–part of the “free market” philosophy for increasing profits?

Who in Australia voted for the AEMO?

What do energy retailers here in Australia actually do? That is to say, aside from the world’s highest per-unit energy bills, what do they actually produce?
Where do they store their wholesale product before they retail it?
Given the network of wires and pipes that deliver energy products directly from production sites, why do we have a “retailer” middle man as part of the equation?

I haven’t been a great supporter of privatisation. But now we have to make it work.

Patrick MJD

I agree with Nick in terms of privatisation of state funded utilities. Private services are another matter. It was taxpayer money that built this infrastructure. I am quite happy to pay for private “enter the name of a service” provided that my former taxes that paid for the same service are NOT deducted from my salary BEFORE I can use it. This is not the case in Australia.

Geoff Sherrington

Or more precisely, Nick, to let privatization work unconstrained, for once. Geoff


no I dont think we DO have to.
buy the gen back for what they paid n a small profit
after all theyve bled us dry already!
and get ALL resources like power gas petroleum and water under govt control . where it IS answerable to the taxpayers and also tax and profits come back TO aussies!
the original commonwealth bank idea was good
we need the same for resources.
and where ceo and other wages are CAPPED and made known.

Patrick MJD

The Govn’t, both state and federal, are doing to Aussies what Enron did to the US (Was it only Californians? I don’t recall). Destroying generating capacity forcing up prices. Interesting both side of Govn’t say coal is cheapest! Well who’d a thunk that!

The costs of variable renewable energy (VRE) and storage have fallen at an unprecedented rate and continue to fall. The business case for these assets relative to conventional generation continues to grow stronger, due to the combination of these cost decreases, relative risk profile, consumer preference, and government support.

Translated into plain language:

” Renewable energy and storage have fallen from obscenely expensive to merely completely uneconomic, which has surprised everyone who expected it to be remotely competitive.. However we can spin this to say that it makes it more competitive, in the same way that 50 tonne truck is more competitive than a sherman tank in terms of fuel efficiency on the school run, when the government us paying 90% of the fuel cost and underwriting the risk, and people just like driving them, and this will please the greens and stop their heads exploding while we get on and build more coal”..

Nick, you are SUCH a card!

Life would be emptier without your performances.

What Nick Stokes’ quote omits is that the baseload units are now not allowed to supply baseload, and that is the reason why they are required to respond to rapidly varying energy system needs. Why are they not allowed to supply baseload? Because the govt has mandated that renewable energy has to be used when available in preference to all other sources (the “MRET” – Mandatory Renewable Energy Target). So we have the absurd situation that renewables get a free run, and baseload power stations are tortured to fill gaps at a moment’s notice. Of course baseloads can’t compete in that situation. They are actually prohibited from competing. All that is needed to get the power systems working smoothly is for the MRET to be scrapped, so that the system operators can choose which power source to use and when, with the decision based solely on what is best for lowest-cost efficient operation.

“Because the govt has mandated that renewable energy has to be used when available in preference to all other sources (the “MRET” – Mandatory Renewable Energy Target)”
No, that isn’t what the RET mandates. It requires retailers to, summed over a year, supply a certain amount of energy from renewable sources, or purchase certificates from others. It doesn’t say anything about what you have to use at a particular time. The reason baseload can be underbid is that renewables don’t have fuel costs.

Geoff Sherrington

Sorry, Nick, when you write –
“The reason baseload can be underbid is that renewables don’t have fuel costs.”
That is just flat out wrong.
Best you stick to your knitting here.
Renewables do not contribute significantly to baseload, they interfere with it. They cannot follow load at all well. Geoff
(Nuclear fuel costs are also very low).

I was responding to this
“So we have the absurd situation that renewables get a free run, and baseload power stations are tortured to fill gaps at a moment’s notice. Of course baseloads can’t compete in that situation.”
The complaint is that renewables do compete, too successfully, with baseload power. And the reason is that they don’t have fuel costs. If a FF station can’t cover its fuel costs at the market price, it is shut down. Renewables don’t reach that point.

Geoff Sherrington

Hi Nick,
You quote this from the AEMO report: “The costs of variable renewable energy (VRE) and storage have fallen at an unprecedented rate and continue to fall. ”
If you are going to rely on quotes, you should qualify them with appropriate caveats.
That statement is so fuzzy as to be meaningless. Are they doing their economics including subsidies and incentives like RET or not? Do they not realise that large scale storage is not yet feasible because it cannot be demonstrated at any realistic price, if at all?
It would be more helpful if you could refer to an economic analysis pitting the essential cost of renewables against coal in the last 20 years, using a competitive economics approach like an intending entrant company into the field would use as a guide to the best type of generation for future investment.
The AEMO’s wise words are so often predicated on the ‘untouchable’ need to keep to the Paris agreement, as were those of the Chief Scientist and various others in the past 5 years.
It is a completely different economic equation when you remove the Paris constraints.
We can then have a future like the best time of the past, when Australia, as you remember, had about the best economy in the world and almost the world’s lowest real electricity costs.


“The costs of variable renewable energy (VRE) and storage have fallen at an unprecedented rate and continue to fall. The business case for these assets relative to conventional generation continues to grow”

A pea and thimble trick here when they lump storage in with solar VRE when we have no such thing. Just the VRE and negligible storage paid for, apart from Snowy Hydro which was used for cost levelling between night and day for thermal generation previously and a unicorn Tesla battery to hide the installation of 9 diesel generators.

You want true level playing field costs Mr Stokes? All the Gummint has to do is remove all subsidies and mandate that no supplier of electrons to the grid can tender anymore than they can reasonably guarantee 24/7 all year round and the freeriding dumpers would be finished. You can’t guarantee them then you keep them until you can-

Paul Penrose

Please explain to me how such a distributed, unreliable system of energy sources will be able to provide “inertia, system strength, and frequency control.” Do you even understand how the voltage and frequency are maintained on the grid while the load (demand) changes constantly?

“Please explain to me…”
AEMO is happy to do that. They say
“• Modelling shows that many renewable developments contemplated in the 2020s are likely to require some level of system strength remediation for their connection, and from the 2030s onwards most renewable developments would be expected to require system strength remediation. A coordinated approach that allows renewable generators to contribute towards system strength for a REZ will be more economic than developing system strength solutions at individual wind and solar farms.”

Can we do it? Yes, we can!
“– AEMO has identified minimum inertia requirements to operate the power system under rare conditions where the risk of regional network separation is heightened. A minimum inertia requirement has been identified for South Australia, flagging an opportunity to optimise this service with synchronous condensers currently being designed for system strength..”

“• Frequency control services will need to be increasingly sourced from non-traditional sources (for example, from battery storage systems, demand-based resources, and renewable generation).
• The need for frequency control services may increase as a result of decreasing inertia, and increasing volatility in the load to be met by dispatchable resources resulting from high penetrations of DER and variable renewable generation, along with changing end-user behaviours.”

Can we affort it? Yes!
“As an approximate guide, a 150 MW wind farm connecting in a weak area of the network could require around 30 megavolt amperes reactive (MVAr) of synchronous condenser support, at an approximate cost of $5 million to $10 million. As there are many factors that could influence system strength mitigation requirements and costs, generator proponents should conduct their own due diligence and discuss the topic with the relevant Network Service Provider (NSP) when considering connecting a generator in a low system strength area.


All this from modelling studies? A good job to model wind or solar on an hourly basis at best.

I have a class degree im electrical engineering and I hadn’t a clue what a synchronous condenser is.
So I looked it up.

Its just a bloody great motor/generator connected to the grid to add some rotational inertia to the system to get frequency control back when you lose the rotating mass of conventional turbines.

NIck appears to not understand that this is short term – seconds only – storage, It does NOT cover anything beyond that.

IIRC correctly there was a need for ’17GW/90GWh of storage’

a few spinning lumps of condenser aren’t gonna do 90GWh

neither are a couple of Tesla batteries.

Once again Nick has done a cherry picked appeal to authority without understanding what in fact he was linking to or quoting.

Sure a windmill or solar panel can be given the rotational inertia of a classic turbine, at a pretty high cost but that only solves one small problem – short term frequency control

it doesn’t solve days of no wind.It doesn’t even solve nights of no sun

90GWh of storage is 3 of the biggest pumped storage installations in the world – Bath County is 30GWh appx.

but I query if even that is enough, or where it could be built in Oz.

Snowy mountains? and then run a cable up to Darwin?

90GWh is enough to keep the whole of Australia going for just three hours.

The nights are longer than that, and if the wind aint blowing, thats an all renewable grid crash

Like all of such reports, these are a picture of ‘what we need’ plus ‘what we hope someone will develop so that it actually works’ plus some dodgy maths.

I’ve seen similar from DECC = the headline is all about renewable energy, with a couple of paragraphs in small font buried in the middle showing a 10 fold increase in nuclear power,

There is a need to be seen to be meeting ‘renewable obligations’ and there is a need to keep the lights on.

so putting sails on a nuclear submarines is the solution…they spin that as ‘diversity’ which is a wod that stupid greens think means ‘good’

“Ministers today announced that in the name of diversity, cars would no longer just have round wheels, but wheels of many different shaaes, and no longer would culturally repressive laws such as this requiring everyone to drive on one side of the road be enfioced. People are now free to choose as their consicience culture and religion dictates, which side of the road to use’

The simple answer is that shorn of subsidy and with externalities taken into account renewable energy is 2-5 times more expensive than conventional plant, and adding in spinning mass pumped storage and batteries, is a LOT more expensive than balancing with conventional plant.

BUT as Germany shows balancing it all with coal plant results is a system that generates as much or even more CO2! rendering the whole point of renewables null and void.

Balancing with gas loses about half the renewable energy carbon gains

Balancing with pumped hydro loses about 25% in terms of average turnround of the storage system.

All of these solutions are way more expensive however than nuclear power.

“NIck appears to not understand that this is short term “
The question that was put to me was exactly about short term:
“will be able to provide “inertia, system strength, and frequency control.””

what is short term about ‘system strength’?

“Oh its OK to walk on, it will hold up for 30 seconds, that’s what we renewable people call ‘system strength’

You are such a card, Nick

“what is short term about ‘system strength’?”

System strength is defined by AEMO (4.3.4) as
“System strength is a measure of the ability of a power system to remain stable under normal conditions and to return to a steady state condition following a system disturbance45”
Short term response to system disturbance.

Geoff Sherrington

Sorry Nick, not a word there about short term. System disturbance includes the Costa Rica scenario of wasted wind farms and solar panels by the acre after the cyclone. These are the important ones for long term design. Geoff.

Geoff Sherrington

Correction Puerto Rico

How long do you think that example of a “system disturbance” lasted? That is, how long did it take for the system in Puerto Rico to “…return to a steady state condition…” following Hurricane Maria?


It is true that wind can provide system inertia if equipped with synchronous generators (I believe Texas requires this already). It will however raise the cost of wind power quite considerably.

Alan Watt, Cliamate Denialist Level 7

Which is perfectly fair. Wind farms should also include local storage. That way a promise to supply a specified amount of stable, synchronized power is credible. As you say, between frequency control and storage, that raises the cost of wind power considerably. But then again, since the wind is free, they can afford it, right?

As others have noted, not all megawatt hours are equal. Until renewable power can be delivered as promised, cost comparisons are misleading.

Geoff Sherrington

But none of this fancy mix and match is as cheap as we had a decade and more ago, when plants were designed and adopted on the basis of cost, performance, dispatchability, inertia etc., in an overall system unconstrained by mandatory recognition of renewables, which at that time did not make the cut. Nor do they do so now. They have caused a great deal of harm, very large cost increases. Geoff

Paul Penrose

What you quoted was almost devoid of any details on how it will be done; just a lot of hand waving. Except for “changing end-user behaviours”, that was quite clear and will probably be the primary way of dealing with an increasingly unstable grid. Get back to me when you have have the engineering details.


I thought that the recent Tesla battery and demo projects in California have shown that a battery tied to the right inverters can provide high quality grid services such as voltage and frequency control. Also short term backup (15 minutes) in case of other generation failure.

Of course all that is sort of the opposite of providing longer term power in bulk.

Yes. Frequency control and voltage stability boils down to having some form of limited storage on the grid and then system to deploy it to meet transient loads

a battery and some computer controlled electronics can do this, or a thwacking great turbine and generator armature spinning can do it without the need to build anything else.

But these are millesecond response, seconds to hour capacity solutions.

They dint solve the dark windless night problem Or the sunless windless winter month problem

Other people have taken the data on wind and solar generation from my site and done with it what it was always intended to do – see how near a renewable grid one could get and at what storage costs.

Short answer. You don’t want to know. Not if you are Nick Stokes.

As I said a few weeks ago when after complaining how wind turbines spoilt the Cornish landscape and on being asked ‘where then did I think they should be put?” my terse answer without a moments hesitation was :

“In a museum”

Adam Gallon

The windless nights, like on 13th July at 4am, when the c 18.8GW of installed wind in the UK, produced 0.07GW of power & being dark, solar produced nothing at all. Repeat that, in a few years time, in a cold January, with a similar high pressure zone sat over the UK & Europe. The outcome is more than concerning.


What is even more worrying is that the scenarios examined by the business and energy people assume that France and Holland will be able to supply 3GW via the interconnections.

Yet this year we supplied France and Holland using coal…

The reality is we are 3GW short of capacity that we can rely on.

If a big plant trips out in winter,1 2018.2019 with cold weather and no wind, and France is in a similar state we are sailing very close to …umm,. A bad metaphor 🙂


When a comment is flagged for moderation, there’s no opportunity to edit it.
AGL post is missing a decimal mark between 2 & 5 (should be 2.5-million).


Nice work Eric. Take a nothing burger, pass it through a few distorted, News Corp filters, then serve it up as click-bait for people living in an Egyptian river.

Patrick MJD

Living IN a river?

This will show you why:

Patrick MJD

Shorten is on ABC with the usual spin…

“blah blah blah…more jobs, cheaper energy and better climate…blah blah blah”

He really said “…better climate…”!!!

So the Govn’t is telling us that “blah blah blah coal is important blah blah blah” and “blah blah blah will be around for the next 20 years blah blah blah”. Is there a federal election on the horizon?

Alan Tomalty

No one has mentioned that the renewables subsidies are NOT coming off. If the subsidies ever come off the whole system collapses. So, does this mean the consumers are stuck with paying the subsidies FOREVER?

Patrick MJD

I would say likely given the fact Aussies really are lame at checking what policies our politicians impose on them (I am not an “Aussie” yet. But I sure get reamed in taxes tho). Its OK though, whatever sports “enter whatever you like” game is on TV, they glide along on their “smart fone with megga data” oblivious to what is actually going on. An analogy would be boiling a frog.

In the UK they are being quietly phased out, New plant has to use the CfD mechanism, or take market rates.

ROCS are I think gone

The UK government has proposed wide-ranging reforms to the UK electricity market which will eventually see feed-in tariffs with contracts for difference (CfD) replace the Renewables Obligation as the main renewable generation support mechanism.[28] Unlike ROCs, CfDs will also be available to generators of nuclear electricity.

Other than with respect to large scale (>5MW) solar photovoltaic power projects and onshore wind power projects, the Renewables Obligation will remain open to new generation until 31 March 2017, allowing new renewable generation that comes online between 2014 (when it is anticipated the CfDs will start) and 2017 to choose between CfDs and ROCs. After that date, the government intends to close the Renewables Obligation to new generation and ‘vintage’ existing ROCs, meaning that levels and length of support for existing participants in the Renewables Obligation will be maintained.

Needless to say neither are attractive right now

Phillip Bratby

They could always take the extremely expensive (stupid) option and convert the coal units to burn woodchips imported from the USA. The UK politicians are more stupid then the Aussie ones.

EU dear. Its they that started the whole ‘renewable obligation’ thing to please the German Greens (when they were in coalition) and German wind turbine manufacturers.

Biomass was classed as ‘renewable’ so that German canola growers got a bung too, for biodiesel.

Britain dutifully copied it all down and an complete turnip head called Ed Milliband wrote it all into the ‘Climate Change Act’ after having his ear bent by some many green/renewable lobbyists that they still stick out…

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..and Drax said ‘we can burn biomass, do we get a big subsidy too?’ They were co firing things like waste straw already

And the government said YES.

So Drax borrowed an obscene amount of money and built storage and wood pellet handling facilities to convert a couple of boilers to all wood.

And the government turned round and said ‘we lied. You will only qualify for a reduced subsidy’

But at least they were allowed to keep operating, which was in doubt with coal, due to the turnip head’s legislation.

Drax is the UKs biggest power station. 4 GW IIRC

It will be all wood or gas soon.

They look set to replace coal generation with CCGTs instead of wood for unitst 5 & 6

This is actually a very smart idea.
It would take the whole site up to 5.6Gwe
It would use existing steam turbines and boilers, but add gas turbines as the heat source and power for yet more generators.

And it takes on board the feeling that biomass is a political short term fix, and the political mood is shifting

I hope they do go gas. Britain desperately needs that sort of baseload power increase to replace coal..

Cold winters in Oz are surely not the main concern, it is heatwaves that cause enormous spikes in demand, sometimes with a day or two of very light winds during the critical early evening periods.

It ain’t rocket science, if you’ve got low cost dispactable power stations, DON’T LOSE THEM.

Patrick MJD

We have lost at least two in recent years.

John in Oz

Over the 20-year plan period, AEMO anticipates the retirement of a substantial portion of the NEM’s conventional generation fleet. A significant number of coal-fired generators in the NEM have either advised that they are closing or will reach the expected end of technical life in this plan period.

All references to ‘retire’ and ‘replace’ in the AEMO document refer to conventional, fossil-fuel generators. There does not appear to be anything related to the retirement/replacement of wind and solar generation which is generally been cited as around 25 years of operation.

At the expected retirement of the reliable, dispatchable, cheap conventional generators, all of the current unreliable, non-dispatchable, expensive wind/solar systems also need to be replaced.

Patrick MJD

That’s the plan. Having coal “online” for 20 years is just to appease the voters. Once the 2019 election is gone, so will be cheap coal power for Australians. Chinese and Indians will be OK tho.


I fortunately live in tropical North Queensland and when it gets down to our annual minimum of about 7-10C (was for a week or 2 in June and a couple days so far in July) we feel cold but mainly because we have no heat and our house is set up to let the cold in due to the more consistent higher temps and humidity – air flow is key here 10-11 months of the year. And lets face it, 10C is not overly cold.

The humorous (but potentially tragic) thing is I have a relative who lives in Adelaide (temps get consistently below 0C there in winter) who is a big supporter of “green energy” which may be unable to power their life supporting heat when they really need it.

On the flip side, we use our A/C for maybe 20 days a year and I elect to stand in the summer midday-to-afternoon sun for 5 hours every weekend for a game of cricket when the majority of summer temps are 32-38C with 85-95+% humidity.

“Heat” is something you can get used to with little cooling, but you need a source of heat when temps drop below 0C consistently. It is no wonder Southern Australians are now talking about the cost and reliability of power.

Steve O

“The least-cost transition plan is to retain existing resources for as long as they can be economically relied on.”
— A surprising conclusion. I believe this was also a feature article in “Finance DUH!” magazine. They also mentioned that the lowest cost car ownership strategy is to replace your vehicle when it can no longer be economically relied on. It turns out it’s NOT more economical to scrap your car halfway through it’s life, as is commonly thought.

William Sweeney

Modern ultrasupercritical pressure coal plants are 40% more efficient that older lower pressure designs. Want to cut pollution by 40% and maintain reliable power? Update the boilers and turbines.

John in Redding

“Coal needed for decades to keep Australian power prices down” These brillant administrators are just now figuring this out!! Not to mention they will be necessary in order to keep the lights on also. Wind and solar will never take the place of all fossil fuels.

Crispin in Waterloo

Storage: 90 GW?

In what? How?