Coal plants failed in Queensland heatwave on day of record demand | RenewEconomy

Coal plants failed in Queensland heatwave on day of record demand

Are Australia’s coal and gas generators able to power Australia through next summer’s heatwaves? The evidence of last summer suggests they cannot be relied upon, with a new report showing how coal plants melted in the Queensland heat on a day of record demand.


Are Australia’s coal and gas generators fit for purpose to power Australia through next summer’s heatwaves? The evidence of last summer suggests they cannot be relied upon, with a new report showing how coal plants melted in the heat in Queensland on a day of record demand.

The Australian Energy Regulator has documented yet another occasion when fossil fuel generators failed to perform in the midst of a heatwave, raising questions about the ability of the country’s ageing coal fleet to meet demand in future heatwaves.

A new report from the AER looks at the soaring electricity prices on February 12, 2017, when high temperatures across the state caused record demand despite the day being a Sunday, when most business and much manufacturing was closed.

The principal reason, the AER notes, was the sudden withdrawal of more than 790MW of coal and gas capacity – all due to technical faults related to the heat.


The plants’ absence nearly created a shortfall of supply, with emergency back-up called on as the 5-minute price soared to more than $13,000/MWh on 11 occasions between 4.35pm and 7.05pm, to meet surging demand that tipped at a record 9,369MW.

The AER report on the events of February 12 is the latest of a string of reports noting how coal and gas plants have failed, or lost capacity due to problems in the heat.

Just a few days earlier, on February 10 in NSW, the loss of 1,000MW of coal capacity and the sudden failure of another 1,200MW of gas generation nearly tipped the state into widespread blackouts.

Just four days before that, on February 6, a total of 3,000MW of coal and gas capacity was lost in NSW and Queensland, mostly due to heat related faults. And on March 3, the sudden failure of the two major gas generators almost caused another system black in South Australia.

On these occasions, authorities said that renewable energy was to thank for keeping the lights on. Other analysis has pointed out that rooftop solar has saved significant amounts in wholesale electricity costs, with one report putting the savings in NSW during the heatwave at nearly $1 billion.

That’s ironic, because much of the mainstream media attention around the risk of blackouts and soaring prices has centred around the role of wind and solar – but it is the performance of the coal and gas generators that is making grid operators nervous.

Queensland is a case in point. It does not, as yet, have any large-scale wind energy apart from an old 12MW wind farm; and has only one large-scale solar plant, a recently built 20MW facility at Barcaldine. Much more – some 2,000MW – is in the pipeline, but for the moment the grid relies on its coal and gas plants for supply, and its high levels of rooftop solar.

rsz_screen_shot_2017-05-18_at_91226_amOn that Sunday, high demand was expected because of the heatwave, which had affected South Australia and NSW on previous days. It reached 37.6°C in Brisbane, up from 37°C the previous day. This was almost 8°C above the February average maximum, and maximum temperature records were broken in several parts of the state.

Still, because it was a Sunday, high prices were not expected four hours out, even though demand forecasts had been lifted significantly. But in the end they jumped higher – demand hit record levels, but the killer punch was the failure of units and reduced output from six different coal and gas generators.

“The actual spot price was much higher than the four-hour ahead expectation because a significant volume of low-price local Queensland supply became unavailable,” the AER notes.


It catalogues the incidents above.

The unexpected withdrawal caused the Australian Energy Market Operator to declare an actual lack of reserve (LOR) 2 condition, one step short of load shedding. All it needed was for one more thing to go wrong, and power to homes and businesses would have been lost.

The situation was made worse because of constraints on the network imposed by the market operator that reduced the flows from NSW from a potential 600MW to just 40MW. Constraints have been imposed by AEMO at various points in case of a failure at the Kogan Creek coal-fired power station.

The events of the past summer has caused one of the biggest network owners to complain about the reliability of fossil fuel generation. Spark Infrastructure, which owns networks in Victoria and South Australia, said gas generators were proving unable to deliver reliable power at times of peak demand.

It also accused them of charging excessive prices for both their retail operations and their generation. This follows questions about the reliability of fossil fuel generators and their ability to deliver the grid security they are paid handsomely to do.

AEMO has admitted that some legacy coal and gas generators have no performance standards, and it may not even know what their control settings are. A point underlined by Tom Butler, in his piece today, which analyses numerous issues with governor controls and other issues, and by other submissions which point to system weakness from fossil fuel generation.

The AER has been chronicling all sorts of occasions when coal and gas generation has been lost due to the heat. Apart from the events on February 6, February 10, February 12 and March 3, mentioned above, more capacity was lost in January, mostly the result of “heat” issues that forced coal and gas generators across the state to lower capacity.

On Friday, January 13, for instance, between 600MW and 670MW of coal and gas capacity suddenly became “unavailable” due to “plant limitations, some of which related to the high temperature.”

And, of course, there was the February 8 incident in South Australia, when 90,000 people lost power for up to 45 minutes when one major gas unit sat idle while the lights went out, and as several other gas units failed in the heat.
Print Friendly, PDF & Email

  1. john 4 years ago

    In January and February ultra reliable suppliers proved not to be and only now the information becomes available, this is May.
    Of course in the previous months many press releases have been made touting the need for a new coal fired generator.
    I expect this reliable generator will be paid for by taxpayers then sold for the usual premium of $1 so private enterprise will show government how to make a profit.
    The sooner a large number of RE generator installations are built from one end of the state to the other the quicker a cheaper and more reliant system will be installed.

  2. Stephen Wootten 4 years ago

    Any detail as to why they failed due to heat?

    • john 4 years ago

      Look at the tables under Rebid Reasons for instance.
      { change in ambient conditions and backpressure limitations }
      { inlet temperature }
      { condenser limits }

    • DJR96 4 years ago

      The question should be, did they really even fail?

      Re-bids must include a valid reason for the change. The system used to only provide space for 64 characters so they tended to be somewhat coded and overly brief. They now have 512 character space but the prior habits haven’t changed to utilise it. It has been as cryptic as “RL”, which meant review log. Which didn’t provide any useful information whatsoever.
      AEMO can receive dozens of these a day, and can be busier during a heatwave. So they don’t even get looked at much. I think it is only if the market cap is reached that the AER is obliged to investigate and then they’ll have a look. But really all the operator has to do is enter some details into the logbooks that would support the reason they gave. Nothing to really prove that there was ever a real problem.

      Why is this happening needs to be asked.

      Because during times of high demand when supply is tighter than usual, they can make a re-bid for exorbitant prices and if AEMO has to dispatch any generation at that high price, all generators then receive that price. One 5-minute spot price will guarantee over $2200/Mwh for the 30-minute settlement period. See in the graph above, 5 of the 8 spikes were for just one 5-minute period. So once they’ve got some high re-bids in they have a “breakdown” and withdrawn some generation from the market. Which forces AEMO to dispatch the high priced unit.

      It is just the way the whole offer/bid and dispatch process works. There are spot traders employed to exploit it as much as possible. AEMO can only work with the rules and regulations they are given. Are they aware of this exploit? And will they strongly advocate for rule changes to fix it? (Given that they are 40% owned by the market participants AND a number of board members are from within the industry)

      The whole industry is supposed to abide by the National Electricity Objective NEO – “To promote efficient investment in, and efficient operation and use of, electricity services for the long term interests of consumers of electricity with respect to – price, quality, safety, reliability, and security of supply of electricity; and the reliability, safety and security of the national electricity system.”
      But all this market behaviour is anything but.

      Have I just stumbled upon one of the greatest ongoing corporate frauds of the century??

  3. Sally Noel Triggell 4 years ago

    Funny, we haven’t heard any of this from the MSM or the ABC.

    • Joe 4 years ago

      Where is he ABC’s Chris Uhlmann…..”intermittent of fossil fuels”…now that’s a headline for our man Chris !!!!

  4. phred01 4 years ago

    Lack of maintenance is the root cause

  5. DJR96 4 years ago

    Call me cynical and sceptical, but I think there is another whole aspect going on here.

    During high demand periods some of these generator operators are gaming the market by rebidding capacity bands (they can adjust price per band but that is easily side-stepped) and then having a very mysterious “breakdown” to cause dispatch of these high priced units which then obtains the high price on all their other remaining operating units. Nothing “illegal” with the practice and the market system is enabling it to occur. But it is completely contrary to the NEO. And we’re all paying for it. And if this system is not fixed before next summer, expect plenty more of the same.

    • jamcl3 4 years ago

      That sounds plausible to me, at least for part of it. That would be the same game Enron played many years ago and many miles away.

Comments are closed.

Get up to 3 quotes from pre-vetted solar (and battery) installers.