14 pages

These Key Observations follow in the vein of:

1)   the 22 x Key Observations included in GenInsights21, and

2)  the 14 x Key Themes in the earlier GRC2018.

45 pages

(more detail than prior Quarterly Updates)

In this appendix we take a look at a number of different ‘heartbeat’ metrics that help to identify the overall health of the NEM, including:

1)  Weather factors (like temperature)

2)  Prices

3)  System inertia

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With GVSC we’ve been analysing system inertia as far back as in the GRC2018, as highlighted with this article of August 2019.

More recently the AEMO has been publishing its own derivation … which allowed us (beginning with the 2022 Q4 Update) to begin highlighting how the two different measures compare:

(a)  Our bottom-up estimate, showing contribution from different types of plant; and

(b)  The AEMO’s published regional aggregate.

With data from the 2023 Q1 update, on 20th July 2023 Jonathon Dyson published his article ‘Let’s talk about inertia’ via WattClarity – including a review the lowest inertia in Q1 202 (on 4th March 2023 both NEMwide, and in SA).

Future Quarterly Updates continue this process.

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4)  Frequency Performance, which is topical given exploration by others, such as Allan O’Neil in February 2023.

5)  Instantaneous Reserve Plant Margin (IRPM) … following from its inclusion in the 2022 Q3 update:

——-

With respect to the 2022 Q3 update, one small snippet of the content of that Update was shared with WattClarity readers on 6th November 2022 in the article ‘Long-range trend of Instantaneous Reserve Plant Margin (IRPM) and focus on Q3 2022 – from GenInsights Quarterly’.

As discussed in Appendix 1 for the 2022 Q4 Update, what a different quarter this one was!

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6)  Following its addition in the preceding 2023 Q2 release, we continue analysis of LOR status (both actual and forecast):

7)  new to the 2023 Q3 release, we have added in analysis of the NEM-wide ‘% VRE’ for the focused quarter.

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During 2023 Q3 in relation to % VRE the early days of July 2023 particularly stood out, as a result of which we’ve progressively added successive stages of a Case Study on WattClarity:

(a)  on 6th November 2023 we posted  ‘Case Study (part 1) of low % VRE NEM-wide on 3rd and 4th July 2023’.

(a)  on 7th December 2023 we posted  ‘Case Study (Part 2) of Low % VRE NEM-wide on 3rd and 4th July 2023’.

(c)  with more to come …

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8)  Also added in the 2023 Q3 release has been analysis of Interventions in the market over the preceding 12 month period.

… + others.

29 pages

In this appendix we take a look at the changing nature of Grid Demand, which necessitates looking into:

1)  Different shapes of demand:

(a)  Starting with ‘Grid Demand’

(b)  But then also analysing Rooftop PV shapes to also assess ‘Underlying Demand’.

2)  Beginning with the 2022 Q4 Update, we’ve also added in some analysis of the forecastability of ‘Operational Demand’

… this uses a method of ‘Forecast Convergence’ we introduced in GenInsights21 to assess the changing challenges of forecasting what ‘Operational Demand’ will be 24 hours from the point of dispatch.

78 pages

(continues to expand in detail)

In this appendix we take a look at different aspects of the performance of Wind and Large Solar assets (separately and together), including:

1)  Production

2)  Commercial Performance

——-

With respect to these unit-level statistics for 2023 Q3, on Tuesday 5th December 2023 we posted how  ‘Rooftop Solar is crushing* the returns for Large-Scale VRE’.

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3)  Curtailment

4)  Self-Forecasting

… and in particular for 2023 Q1 what changes in usage patterns can we see for those Solar Farms and Wind Farms who have deployed self-forecasting – given:

(a) AEMO upgraded its AWEFS and ASEFS forecasting systems on 23rd November 2022; and

(b) The 3-month long ‘Grace Period’ ended on 23rd February 2023

5)  ‘Forecast Convergence‘ for aggregate VRE Capability

(a)  how accurate are the AEMO’s forecasts of Wind + Large Solar capability across the NEM, 24 hours from the point of dispatch?

(b)  given the growing installed capacity, with more Wind and Solar Farms being developed, to what extent is this challenge growing?

6)  Aggregate Raw Off-Target

(a)  in these Quarterly Updates, we continue to watch what’s happening in terms of collective deviation from Target across all the Wind and Solar Farms – updating and extending the analysis covered in WattClarity articles to 2020.

(b)  Following the 2022 Q4 Update, we shared ‘some revelations in GenInsights Q4 2022 about Aggregate Raw Off-Target for Semi-Scheduled Units’

(c)  Following the 2023 Q3 Update, we shared ‘Case Study (part 1) of large collective under-performance for Semi-Scheduled assets on Friday 18th August 2023’ … and will (time permitting) explore more about this event under this category on WattClarity.

(d)  In subsequent Updates we continue to explore…

+ more to come.

40 pages

(growing in detail)

In this appendix we take a look at different aspects of the performance of (fully) Scheduled assets (at various levels of bundling), including:

1)  Performance specifically through Q4

2)  Aggregate Scheduled Target (AggSchedTarget):

(a)  In absolute terms

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With respect to the 2023 Q1 update, there are three snippets to be shared here on WattClarity:

i.  On 14th May 2023 we shared how ‘we’re not building enough replacement dispatchable capacity’

ii.  On Wed 31st May 2023, we shared ‘Digging further into ‘Aggregate Scheduled Target’, to understand what Dispatchable Capacity is actually required’

iii.  On Wed 30th Aug 2023, we shared ‘Case Study of high AggSchedTarget on Thu 30th Jan 2020 and Fri 31st Jan 2020 (part 1!)’ and will continue with more analysis to be collated under this category on WattClarity.

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(b)  Ramping from one Dispatch Interval to the next

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During 2023 Q3 we found 7th, 8th and 9th Sept 2023 particularly of interest, such that we started an evolving Case Study as follows:

i.  on Tue 14th Nov 2023 we shared  ‘Case Study (part 1) of Aggregate Scheduled Target on Friday 8th September 2023’ .

i.  on 6th Dec 2023 we shared  ‘Case Study – Severe Weather Challenges Day-Ahead Forecasts for 7, 8, 9 September 2023 .

iii.  and will explore further

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(c)  Daily ramping (i.e. MIN requirement to MAX requirement over the day)

3) Forecastability of AggSchedTarget

(a)  During 2023 Q3 we found 7th, 8th and 9th Sept 2023 particularly challenging as a result of the forecastability

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4)  Firming capacity development schedule, matched with coal closure schedule.

36 pages

The 44 x coal units still operational in the NEM in Q1 2023 (down 3 units, after 3 units at Liddell closed in 2023 Q2) are a special subset of dispatchable plant that have been addressed in more detail in this particular Appendix – because:

1)  They still provide a large share of the Energy consumed in the NEM (and also the ‘Keeping the Lights on Services’);

2)  But suffer from the big drawback of high emissions intensity.

What this contains includes:

1)  Performance specifically through the quarter in focus

2)  Coal unit ‘dependability’

In the 180-page analytical component of the GRC2018 we included an extensive focus on the changing nature of different aspects of coal unit ‘dependability’.  This was extended and updated in GenInsights21.

Now, in each quarter, we’re extending and updating further, with the inclusion of analysis of:

(a)  Changing levels of Unavailability

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Following the 2022 Q4 update, on Mon 6th March 2023 we shared ‘Unavailability of coal units hits 24% across calendar 2022 (but they are *not* collectively tripping more often)’ … and we continue to track how this metric is changing as successive quarters roll past.

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(b)  Three different metrics that help to indicate the changing rate of ‘Sudden Failure’:

i.  number of Starts,

ii.  number of ‘Sudden Trip’, and

iii. Aggregate Raw Off-Target.

(c)  Recently added to these Quarterly Updates, we’re now also separating out all hours in the quarter for each of the remaining coal units into three categories (Operational, Planned Outage and Forced Outage), which makes it clearer which units appear to be  struggling and which units don’t appear to be struggling.

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Some of this information was shared on Thu 19th Oct 2023 in the article ‘Two pieces of information (about Eraring Power Station) from the Origin Energy 2023 AGM’ … following the 2023 Q2 update.

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3)  We also look at ‘Forecast Convergence‘ for Aggregate Coal Unit Availability across these ‘still operational’ coal units for this quarter.

4)  Each quarter we take an updated look at the Closure Schedule.

39 pages

In this Appendix, we look at:

1)  Regional Energy Balances

2)  Regional Transfer Duration Curves

3)  Specific interconnector operations (including, continuing from the 2023 Q1 update, the impact of various types of constraint)

4)  Renewable energy congestion

… to augment what

5)  note that there’s no new information this quarter about Marginal Loss Factors (MLFs) in this issue, but has been in other updates when new information is available.

… and in future Editions will add in other aspects.