Graph of the Day: Negative prices in windy South Australia | RenewEconomy

Graph of the Day: Negative prices in windy South Australia

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South Australia electricity prices plunge into negative territory.

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This graph caught our eye, tweeted by Simon Holmes a Court of the newly formed Energy Transition Hub, showing negative prices in South Australia this morning.

The negative prices didn’t last long, they really do. What’s interesting about this is that AEMO has not intervened to limit the amount of wind generation, as they sometimes do if they cannot find enough gas generator to switch on.

At around the time of this pricing, South Australia had some 1280MW of wind and about 480MW of gas generation. AEMO had imposed a “constraint” on power coming into the state on the interconnector, but given the wind available that was largely academic.

Intersting to note that Queensland electricity also low at $24/MWh – possibly courtesy of relatively low demand and the more than 1,100MW of rooftop solar powering houses, businesses and being put back into the grid.

Those prices are expected to become more common during the day as the 2,000MW of large scale solar comes on line in the next 12 months. So far, the state has just one 20MW solar farm on line.

Queensland prices have been higher in the last month because of the closure of Kogan Creek for maintenance, with the other state-owned generators taking advantage of the relative “scarcity” to push up prices.

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This graph – from the AER’s latest weekly price report – shows that South Australia has had lower costs than Victoria, and actually had lower costs than Queensland too until the state government told the generators to stop gaming the system.

South Australia and Queensland have historically had the highest electricity prices due to the small number of generators and the dominance of two or three energy companies over the market.

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  1. Albery Moray 2 years ago

    The SA government’s new gas turbines at Elizabeth and Lonsdale started operating today. No need for AEMO constraints on wind now?

    • Cooma Doug 2 years ago

      The thing about wind and solar is the predictability. Weather forcasting is great.
      They have some unit failures but they are single didget MWs. Fossils disappear 100% with no warning big numbers and it is costly security to make room for their failure.

    • Rod 2 years ago

      I spotted a very small “other” on the NEM Watch widget today . Maybe they were testing the new generators.

      • Nick D 2 years ago

        Yes rod i niticed this too. Is there anyone who knows what SA’s other is?

        • Rod 2 years ago

          As these will use diesel for now, I would have expected liquid fuel to show on the widget. As wind was flat out we can assume the battery wasn’t the reason.

          • Michael Murray 2 years ago

            I’ve seen that liquid fuel come up as a tiny sliver a few weeks back for SA.

        • Paul McArdle 2 years ago

          Thanks Nick, and Rod,
          It was the emergency generators starting under commissioning – as noted here:

          Fuel Type will be updated shortly in the widget, after manual verification (anything new is automatically filed under “other”)

          • Rod 2 years ago

            Hi Paul,
            Did you see multiple GE LM2500+ units started up Friday 10/11 about 3:45pm CST?
            Spot hit $200MWh before they did.
            I’m very surprised. I’ll bet there are some grumpy Gentailers.

    • Paul McArdle 2 years ago

      See here, Albery:

      These plants should (if operated as the Govt states they will) have no effect on the constraining of wind farms. They are emergency insurance only.

    • Mike Shackleton 2 years ago

      The Tesla battery is partly commissioned as well which is why AEMO may have lifted the constraints on wind. The battery is designed to operate long enough for a Gas unit to go from cold to full output without the need to sit in standby idling and burning gas.

  2. Cooma Doug 2 years ago

    This is good and demonstates the room for storage all over the grid. You can be paid to charge your battery.

  3. Rod 2 years ago

    Maybe we still have curtailment.

    Direction – South Australia Region 27/10/2017

    In accordance with
    section 116 of the National Electricity Law AEMO has issued a direction
    to a participant in the South Australia region.

    The direction
    was necessary to maintain system strength in SA, following a credible
    contingency event AEMO would not have been able to return SA to a secure
    operating state within 30 minutes.

    The direction was issued at
    1330 hrs 27/10/17, with effect from 1430 hrs 27/10/17. The direction is
    expected to stay in place until 0430 hrs 29/10/17.

    • neroden 2 years ago

      Time for South Australia to repeal the “National Electricity Law”. Turns out that for bizarre reasons it’s a *state* law. Get out of the NEM and let the rest of the NEM hang… if SA leaves, Queensland will leave next.

      • Rod 2 years ago

        Yes it is ironic that SA has final say on the rules but the Feds keep bashing us.
        We were sold a pup and I would love to see the NEM die a natural death.Still have cross border trade but local oversight over system strength and generation.

  4. solarguy 2 years ago

    Can anyone explain -$42.92 for wind power, how in hell does that work for the owners and investors?

  5. Joe 2 years ago

    The NEG…delivering neg prices perhaps.

  6. Michael Murray 2 years ago

    Yesterday SA was sending 500MW wind power to Vic and today it seems to be 200MW gas

Comments are closed.

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