In a week when (thankfully) many businesses were taking a break, many parts of the NEM sweltered in temperatures that were too high to be funny.

Despite the fact that commercial/industrial loads were lower than they would otherwise be, the total demand in the NEM reached a new maximum of just under 30,000MW – as shown in NEM-Watch here (please click on the image for a larger view):

Note in this image that the NEM-wide Instantaneous Reserve Plant Margin (RPM) reached a low of only 16%, which meant that supplies were being stretched to the limit, even though demand was lower than it might have otherwise been (though it should be noted that some generators had taken advantage of the slackening demand to perform essential maintenance).

The low level of instantaneous reserves is also reflected in the high prices exhibited right across the mainland NEM regions.  Unfortunately Basslink was not operating in commissioning during this period.

These prices on the 30th were only some of the high prices experienced during the week (and even on Saturday 31st), as illustrated in the series of charts below that have been developed through use of NEM-Review:

Generators in NSW

Note the reduced production at Bayswater at the time of the price spike and the increases in production at some Delta stations at the same time.

Generators in VIC

Note also the Yallourn W unit coming offline on an outage at the time of the price spike on Friday 30th December.

Generators in SA

Note the Pelican Point unit was offline until Saturday 31st.