AEMO says coal withdrawal won’t impact South Australia reliability

South Australia next March will become the first Australian mainland state to go without locally-produced coal-fired generation, but the Australian Energy Market Operator says it will not impact on the reliability of the grid.

AEMO, which takes responsibility for the running the grid in Australia, issued an update on Monday following the announcement by Alinta Energy that it will close its remaining generator, the 546MW Northern Power station in Port Augusta, by next March.

The early withdrawal, it says, “is not expected to change the projected extent or timing of the Reliability Standard breaches” that it had previously forecast.

But it will make the state more reliant on wind energy – and presumably solar, which on occasions is providing more than 20 per cent of day-time demand – and on the inter-connections with South Australia.

AEMO says this will create more opportunities for those providing support services such as frequency regulation. This could be met by gas generators, or wind farms, or even battery storage.

AEMO does serve a warning, however, that if high demand coincides with a time when there is little wind, and gas plants are not available, and there is a low level of imports through the inter-connector, either through outage or high demand in Victoria, then the South Australia grid may experience supply shortfalls.

(Before the report was publicly available it was given first to some mainstream newspapers, including The Australian, which took the opportunity to say: SA risks power shortfall because of wind farm dependence.)

Actually, the local grid risks power shortfalls because it depends equally on wind farms, its gas plants and the inter-connector, and the conditions in Victoria. On the rare occasion that all three should fail, then it says some consumers might not get all their power needs for brief periods.

AEMO south australia

It says that even with the Alinta coal assets, the risk of this happening in 2017/18 grows to just 2/10,000 – meaning a chance of just under two hours of outages in any one year.

With the absence of coal, there is an ever so slight increase next financial year, and when Torrens A gas plant closes the following year this increases to about 6 hours in any one year. The reliability standard is to meet demand for all but 20 hours of the year.

This graph above shows how comfortably the South Australia system meets Australia’s high reliability standards, even without local coal power.

Mark Stedwell, the head of NEM system capability, told RenewEconomy that South Australia has the highest penetration of variable renewable energy (wind and solar) anywhere in the world. It is currently more than 40 per cent.

But while it can often deliver more than 100 per cent of its energy needs from renewables, the state is still reliant on the main grid, through the main inter-connector, for ancillary services such as frequency.

Stedwell says this is creating new opportunities for frequency services in South Australia. It has been provided by coal and gas plants up to now, but there is no reason why wind farms could not provide the same function, it’s just that none have decided to do so until now. Battery storage is another option.

“Any technology that can give a fast injection of power, or reduction in power, is able to provide the sort of services that might be needed,” he said.

Stedwell says South Australia is uniquely challenged because it relies on that one inter-connector, unlike Germany which has multiple, more significant links with neighbouring markets. Still, in Germany, there is a big push for battery storage to provide frequency control and other services.

Comments

8 responses to “AEMO says coal withdrawal won’t impact South Australia reliability”

  1. barrie harrop Avatar
    barrie harrop

    High risk base load in Sth Aust depending on Victoria interconnector which goes through one of the worst bush fire zones on earth.

    1. Martin Nicholson Avatar

      But it’s not just the Heywood connector. Plenty of coal fired generation comes down through the Murray link connector.

      1. Giles Avatar

        Stedwell told me today that murray link does not provide much in the way of ancillary services.

  2. Mark Diesendorf Avatar
    Mark Diesendorf

    According to previous reports published in RenewEconomy, two north German states, Mecklenburg-Vorpommern and Schleswig-Holstein, each have 100% net renewable electricity, mostly wind, averaged over a year. (The ‘net’ means they trade electricity with each other and other neighbours by transmission line.) So, although South Australia it is running very well in the Renewable Energy Cup, it still has some distance to go.

    1. onesecond Avatar
      onesecond

      My thoughts exactly, they make it sound as if 40 percent intermittent renewable electricity in a state grid would be a big deal or something when it is elsewhere 100% already. If there is an interconnector shortage, just build a new one. Or a battery or power to gas or whatever.

  3. Brad Sherman Avatar
    Brad Sherman

    No doubt AEMO already factor that in in their 2:10000 and 6:10000 figures. Not a high risk at all.

  4. Les Johnston Avatar
    Les Johnston

    NSW consumers have had power outages in various areas since electricity was first supplied. We adapt. What is the problem with renewable supply compared with outages using coal generated supply?

    1. Black_Texta Avatar
      Black_Texta

      One word.. cost. As seen over the last few months since the PA shutdown, power prices have surged in SA – it is solely due to SA relying on peaking plants to provide stability to the network. You didn’t have to be an Einstein to work out that Peaking Plants would make a killing in SA when PA shut down.

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