AEMO speaks directly to Wind and Solar Farm operators – please alert us to temperature limitations on your assets

Watching the NEM again through our ez2view dashboard software this afternoon, I was stunned to see Market Notice 72015 published at 15:47 this afternoon.  It says:




Notice ID               72015

Notice Type ID          Subjects not covered in specific notices

Notice Type Description MARKET

Issue Date              Monday, 23 December 2019

External Reference            Semi-scheduled and intermittent non-scheduled generation availability under extreme high temperature



Refer AEMO Electricity Market Notice 72013.

AEMO’s weather service provider is forecasting extreme high ambient temperatures across NEM regions. AEMO reminds semi-scheduled and intermittent non-scheduled generators to advise AEMO of any reduction in available capacity caused by temperature derating.

For any reduction in availability please ensure to:

1. Update SCADA Local Limit or, if unavailable, advise AEMO control room to implement a quick constraint to the reduced available capacity level; and

2. Update intermittent generation availability in the EMMS Portal ( to reflect reduced plant availability as per NER 3.7B(b).

Refer to the AER Rebidding and Technical Parameters Guideline:

AEMO Operations


It seems to me that four things have been happening:

Observation #1)  What happened on Friday last week in Victoria (where LOR2 was announced out-of-the-blue and RERT Negotiations commenced – as explored here on Saturday, with more exploration to come) reinforced to us that high temperature limitations on plant are very real.

In our Generator Report Card 2018 (Theme 6 in Part 2 of the 180-page Analytical component) we explored a number of ways in which the NEM is becoming increasingly dependent on the weather:


I have already posted articles about how the majority of the infrastructure supporting the NEM – including Wind Farms, like those affected on Friday last week – seem to have limitations on output during extreme temperatures.  With the way the climate is changing, this will make balancing supply and demand more challenging in these extreme conditions.

Observation #2)  Despite the fact that it is known that all plant experience high temperature limitations, the degree to which these occurred last week both surprised, and alarmed.

That’s not a good development, with another 2-3 hot and dry months ahead of us.

It’s especially not a good development, seeing as (I infer) AEMO’s pleas for additional information seem to be falling on (at least) some deaf ears.

Observation #3)  An unknown number of operators of Semi-Scheduled and Intermittent Non-Scheduled plant (i.e. solar farms and wind farms operating in the NEM) have not responded to the AEMO, or at least have not responded to the AEMO’s satisfaction.

Observation – or perhaps Question #4)  We wonder how such a situation has come about, where it seems (unless I am mistaken) that there are a non-trivial number of generation participants who are seemingly non-responsive to the need to participate in the market in this way?

Are they unaware, or incapable of responding, do they not know what the details of how their plant performs, or is there some other explanation?

In our Generator Report Card 2018 (Theme 5 in Part 2 of the 180-page Analytical component) we pondered whether the form of support for new entry by these types of plant that the AEMO is speaking directly to in this Market Notice was opening up a “them and us” schism, which would lead to situations such as (it appears) we are seeing unfold this week?


Challenging times ahead for the NEM… I hope not this train-wreck.


Whatever any reader can do to pass on this message to those they know who operate these plant would (I am surmising) be greatly appreciated by the AEMO – and also perhaps reduce the risk that the AER will step in to take enforcement action?


PS2 – Wed 24th AM.

Given that I mentioned possible AER enforcement action, it’s worth also linking in this AER Release “Energy businesses must be ready for summer says AER” with the linked “NEM Summer Readiness compliance bulletin and checklist” from Fri 20th December, and highlight the following quote:

Issuing the Summer Readiness Compliance Bulletin 2019, AER Chair Clare Savage said that robust enforcement ensuring compliance with the law is vital in building consumer trust that companies are doing the right thing.

“This week is hot and we’re only just into what promises to be a long summer of severe weather. People understand things can go wrong under extreme conditions, but they won’t forgive outages caused by a lack of preparation or avoidable mistakes.

”The AER will take a dim view of any compliance breaches by energy businesses. It goes without saying they should maintain a strong focus on compliance at all times,” Ms. Savage said.

We can’t say we have not been warned!



PS1 – Tue 23rd PM (a few hours later)

Thanks to those who have been able to pass this message onto the relevant people in VRE Generators.  You might want to stay tuned to the conversation developing:

1) Here and here on LinkedIn; and

2) Here and here and here and elsewhere on Twitter;

… as a result….

About the Author

Paul McArdle
One of three founders of Global-Roam back in 2000, Paul has been CEO of the company since that time. As an author on WattClarity, Paul's focus has been to help make the electricity market more understandable.

2 Comments on "AEMO speaks directly to Wind and Solar Farm operators – please alert us to temperature limitations on your assets"

  1. Obviously wind farms use monitoring software like this one I came across-
    when searching for answers to temperature response of wind turbines and came upon this-

    “When purchasing a wind turbine, the power curve is guaranteed up to a certain ambient temperature (often 40°C). Beyond this temperature, the operating temperature of some components monitored by the wind turbine’s control system may exceed safe levels and initiate a temperature-induced constraint on the wind turbine.”

  2. If it is indeed – as it appears at this stage – that a lot of existing wind farms suffer pretty severe temperature related output constraints above roughly 40C ambient that is… not going to help the public image of renewable energy. It will certainly knock dead any supposed advantage that deployed VRE has over thermal generation in terms of temperature de-rating. Can we put this down to equipment designed for e.g. European climates? Deploying gear in Australia that goes into limp mode once temperatures pass 40C seems foolish/near sighted. We all wait with bated breath…

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