Gate Closure

Gate Closure #1.

This is the one most NEM stakeholders think about when they hear the term ‘Gate Closure‘ … but it’s not the only one.

As noted on this Glossary page about Rebids, under the National Electricity Rules, Scheduled and Semi-Scheduled units need to have submitted ‘Daily Bids’ (sometimes called ‘Initial Bids’) for the following Market Day by 12:30 (NEM time) the day before.

Gate Closure #2

The 10 x price bands for a DUID (or 20 x price bands for a BDU following the IESS Rule Change) are fixed for a Market Day after Gate Closure #1 the day before.

However the volume in these bands can be changed up until (almost*) real time, subject to the provisions for rebidding in the NEM rules (and the AER Guidelines).

—

The ‘almost*’ in the note above reflects the practical implications of the NEMDE solve process – so in practical terms represents some seconds prior to the start of the next Dispatch Interval (i.e. for which the rebid might pertain).

1)  On 7th October 2021 we wrote about ‘Initial look at the latency of all rebids’ and noted that Gate Closure #2 was (up until that time) at approximately T-60seconds.

2)  On 4th December 2021 we wrote about ‘Two recent improvements (in late November 2021) by AEMO in the dispatch process’ and noted that Gate Closure #2 was moved considerably closer to the end of the prior dispatch interval.

Other articles in future might be tagged with ‘Gate Closure #2’.

Gate Closure #3

For Semi-Scheduled units (i.e. which are given a UIGF outside of the bidding process – either by AEMO or via Self-Forecasts) there is a third Gate Closure relevant to these units … and that’s the time serving as a cut-off for that UIGF.

Hence, we’ve termed this ‘Gate Closure #3’.

1)   The article ‘What inputs and processes determine a semi-scheduled unit’s availability’ (published on 11th August 2023) might be a useful reference here.

Other articles in future might be tagged with ‘Gate Closure #3’.