Summer has been and gone (and the winner of our BBQ as the “Best Demand Forecaster in the NEM” will be determined next week) but we could not help but note the elevated temperatures across Victoria and South Australia today awakening demand in those regions from the slumber of the past couple weeks.
In this snapshot from NEM-Watch this afternoon, we see how the demand in both regions has advanced into the yellow zone and, as a result of limitations on the import capability from Tasmania and NSW, the Instantaneous Reserve Plant Margin (IRPM) for the “Economic Island” of VIC+SA dropping below 15%. Prices, as a result of the tighter supply/demand balance, are elevated.
[See here for some context to the range of Instantaneous Reserve Plant Margin experienced across the NEM in the first 9 years of operations]
Re the IRPM I followed the link to the Nem Watch glossary. Unfortunately it no longer provides a formally definition of the IRPM nor a formula. Would you let me know where I can find one?
Regards
Hi Romek
Thanks for pointing this out – this information provides an explanation of the family of bar charts shown:
http://v8.nem-watch.info/help/islands/graphs.asp
IRPM translates the measure of RPM (traditionally used in a longer-term planning context) to real time:
IRPM = (Total Available Generation – Total Demand)/(Total Demand)
Within an Economic Island we substitute:
IRPM ei = (Total Available Generation – Net Demand)/(Net Demand)
where Net Demand = Demand in regions within the Economic Island + Net Exports, which are supplied by the local generators.
Does this help?
Paul