And the winner for summer 08-09 is…

We noted yesterday, in the midst of the excitement, that the previous NEM-wide demand record had been beaten, by virtue of the heatwave assaulting VIC and SA over the day.

We spoke too soon, however, as demand continued to climb through the afternoon. As a result, we have the following numbers to report:

** Note, with respect to these demand numbers, they are “Dispatch Demand Targets”, which mean they come from NEMMCO’s dispatch process (ahead of time) for a 5-minute dispatch interval, and are not metered after the event. The numbers that NEMMCO will be able to provide later (i.e. the metered ones) will be a little different, and probably a bit higher.

The following snapshot (playback from NEM-Watch v8) shows the time when peak demand was recorded – at a time when the NEM-Wide Instantaneous Reserve Plant Margin (IRPM) had dropped just below 15%.


In this snapshot, we also see that the IRPM for the VIC+SA “Economic Island” had dropped to a low of only 2% – we see that both regions (at that time) had only 293MW of “spare” capacity available to call on should any operating unit have tripped offline, or some other drama unfolded (assuming no more power could be forced through the interconnector from NSW, which was constrained at the time, and for most of the afternoon).

As could be understood with such a tight supply-demand balance, prices in VIC and SA were sky-high.

In our second screenshot, we highlight that the demand reached in VIC had exceeded the 90% and 50% probability of exceedence forecasts (in the High, Medium and Low load forecasts) from NEMMCO’s 2008 Statement of Opportunities.

The maximum demand on the day was still about 500MW below the 10% probability of exceedence forecasts that NEMMCO released at the time – thankfully, as we noted (above) that there may not have been sufficient spare capacity to cope with this additional demand.


Hence, we see that NEMMCO has forecast that demand could reach even higher this summer in VIC – indeed, with more extreme weather on the way this week, we may not have long to wait…

For a different take on the industry’s view of what the demand would be, we refer to our “Guess the Peak NEM Demand” competition to find the NEM’s best demand forecaster.

Despite the fact that the competition has (officially) many weeks more to run, we’re calling it closed now, and announcing that the winner of the BBQ is Thao Doan at Stanwell Corporation.

The reason that we’ve done this is because Thao’s guesstimate of 34,600MW was the highest of all the entries we received, from many different market participants and observers. Hence, even though demand may well go higher before summer is out, it’s fair to say that Thao will be the winner.

We’ll be contacting Thao shortly to arrange delivery.

Something to keep in mind, though – that the spike in NEM-wide demand exceeded (considerably) the estimates of a broad range of people working in, and connected with, the industry (including quite a number of traders, analysts and forecasters, etc…)

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.

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