April 2024 enhancements to NEMreview in preparation for IESS

On Thursday 17th April 2024 there was an initial version of a Release Note published (pertaining to enhancements made to NEMreview).   Sufficient extensions were made to this Release Note that it was thought more appropriate to re-publish several days later as this new article.


What is IESS, and why is it relevant to NEMreview?

Some of our clients may be aware – our development team has been investing heavily through the first half of 2024 to prepare various products (including NEMreview) for the  looming IESS market changes.

This Release Note pertains to enhancements made to NEMreview.

However before going into the detail, we recommend you read the background note ‘What is IESS, and why is it relevant to NEMreview?’ that’s been published at the same time, and is intended to explain:

  • More about the IESS change itself;
  • and, importantly, why it is relevant to NEMreview users.

Assuming you have read this linked article first, then read on further below …


What enhancements have been made to NEMreview v7?

In this short release note, we would like to highlight specific enhancements that we have begun to implement in NEMreview v7, with more to come in the near future.

Enhancement #1 = We’ve started to change the tab structure

There used to be a tab named ‘Generators’ featured prominently in NEMreview, but this was increasingly become misleading with the addition of an increasing number of units for Loads in the market … and this has caused confusion at times with our NEMreview clients.

Coupled with this, the number of data series had continued to grow on some tabs, making individual series more difficult to find.

The Solution = as a result of which, we’re rationalizing the tab structure in NEMreview to assist in making data easier to find.

With respect to this image, note the following:

Enhancement #1a = New tabs being added

You’ll see that the first batch of enhancements (on Thursday 18th April 2024) included the addition of a new ‘Units (NEM)’ tab – which has been designed to make it easier for clients to find and select the data they are looking for.

Other tabs to be added soon include:

i.  A tab containing NEM-specific units that participate in any of the 10 x FCAS commodities, and data relevant to that
ii.  A tab containing WEM-specific units (i.e. for the WA market of the South-West Interconnected System).

… for now, you can still find those data points on the ‘Generators (legacy)’ tab.

Enhancement #1b = Generators (legacy)

As an interim step in this process, we have moved the previous ‘Generators’ tab to the end of the menu bar and labelled it as ‘legacy’.

We envisage that this tab will eventually be removed … but only after all the data series you need access to are provided for on more clearly named new tabs.

Users who still want to access data series on this ‘legacy’ tab should note that some of the data series on this tab have been changed, as discussed further below.


Enhancement #2 = Deploying a uniform number sign

As described in the related article ‘What is IESS, and why is it relevant to NEMreview?’, we have invested time to shift all data sets included in NEMreview follow this simple rule:

Positive numbers = represent injections onto the grid (i.e. discharge from a battery, discharge from hydro, generation from coal, gas, wind, solar, etc…).

… remembering Tripwire #3 (introduced with WDRM), this will continue to mean that dispatch of Negawatts will be seen as a positive number (i.e. a supply-side quantity, even if intangible).

Negative numbers = represent withdrawals from the grid (i.e. charging a battery, pumping uphill to a pumped storage reservoir, and consumption by other Scheduled Loads).

Therefore, for those units that will be re-registered as a ‘Bi-Directional Unit’ (BDU) after 3rd June 2024, these values will be positive when generating and negative when charging.

It’s worth stating explicitly, then, for any client who also queries the EMMS directly, that the number sign may on (special corner-case) occasions be the opposite to how data is represented in the EMMS.


Enhancement #3 = Shifting to ‘end-of-interval’ values wherever possible

When we first provided access to this NEMreview v7 application, one of the principally used data points was ‘Initial MW’ for each DUID.

(a)  This was the SCADA snapshot of the units output (or consumption, if a load) at the start of the Dispatch Interval that the time point represented

(b)  But remember that AEMO standard timing convention is that dispatch intervals are time-stamped with the end-of-interval time point … hence this tended to cause confusion with some clients.

Many months ago as an enhancement to NEMreview we added in ‘Final MW’ as a value that time-shifted the InitialMW values to be end-of-interval values.

With the recent changes (April 2024) we have moved to ensure all data is end-of-interval basis.


Enhancement #4 = Improving (clarifying) the data available

At this point, it’s useful to remind readers about this common ‘Analytical challenge (or beginner mistake!) – understanding the difference between a MW and a MWh’ that was published as a discrete article on WattClarity in October 2022…

…  this short article was extracted out of a longer explanation of the gory details of ‘measuring’ demand in the NEM that was published back in 2018.

With IESS prompting the need to simplify the data included in NEMreview moving forwards,  we have taken the initiative to invest further time to simplify

Enhancement #4a = new (clarified) data series on the ‘Units (NEM)’ tab

On this new ‘Units (NEM)’ tab, we have separated off data sets that do not pertain to supply/consumption of ENERGY in Australia’s National Electricity Market (NEM) and stripped back to just 9 x Data Series as follows:

This number is intentionally small, to assist clients in finding/selecting the data series they are looking for.

Noting that we have not yet updated this Glossary with respect to the data series the are now available on this tab, here’s a short note about each of them:

Energy (MWh)

This is a data series that’s a volumetric measure (i.e. MWh) – a positive number is energy supplied to the grid and a negative number is energy consumed from the grid over a period of time.

For a given dispatch interval, it has been derived from linear interpolation between two different ‘Power (MW)’ measurements at the start, and the end, of that dispatch interval.

Power (MW)

This is an instantaneous (SCADA-level) metered rate of production (positive number) or consumption (negative number) for the unit at that particular point in time.

For a generator this is an ‘as generated’ number (i.e. inclusive of  auxiliary energy used onsite in the production process).

Target (MW)

This is the instantaneous required rate of production that’s calculated within NEMDE at the start of the dispatch interval for what the unit is required to

This data:

(a)  Exists for every dispatch interval for each Scheduled and Semi-Scheduled unit
(b)   But does not exist for Non-Scheduled units (except in some particular cases of Non-Scheduled units with Semi-Scheduled requirements).

Capacity (Generation) and Capacity (Load)

These are the maximum potential to inject onto the grid (generation, a positive number or zero) or consume from the grid (load, a negative number or zero), as noted in the registration of the given unit.

Availability (Generation) and Availability (Load)

These are the maximum potential to inject onto the grid (generation, a positive number or zero) or consume from the grid (load, a negative number or zero), as noted in the registration of the given unit.

Availability (UIGF)

This data is only published for the Semi-Scheduled units.  UIGF stands for Unconstrained Intermittent Generation Forecast, and is the energy-constrained Availability for the unit.

(a)  Linton Corbet’s article on WattClarity ‘What inputs and processes determine a semi-scheduled unit’s availability’ from August 2023 would be useful for readers to refer to here.

(b)  It’s particularly important to understand that this UIGF number will be be higher than the ‘Availability (Generation)’ number for Semi-Scheduled units on occasions where MaxAvail in the bid has been used to declare some physical limitation at the plant :

i.  this capability that was enabled for Semi-Scheduled units from 7th August 2023;

ii.  From our GSD2023 product we prepared the article ‘How many Semi-Scheduled units have taken advantage of the market change that went live on 7th Aug 2023?’.

Semi-Dispatch Cap

This data is only published for the Semi-Scheduled units.   The Cap is set when AEMO (via NEMDE) requires the unit to ‘follow’ its Target …

(a)  noting the requirements were tightened from 12th April 2021

(b)  but, even in this case, the Target is more like a Cap than a specific measure to absolutely reach (at least in terms of AEMO Conformance).

Enhancement #4b = changed (clarified) data series on the ‘Generators (Legacy)’ tab

As part of the process of (eventually) deprecating the ‘Generators (Legacy)’ tab, but in the interim period ensuring that it is as correct as possible in relation to Enhancement #2 above (a consistent number sign), we have made some changes/corrections to the data series that were previously available on that tab.

It’s important for users to note that this will have had the effect of changing the output of a user’s pre-configured queries using these series.

… individual clients are urged to speak directly with us if they have concerns about this approach.

With respect to the data series that have changed:

Energy Generated (Estimate)

There are two changes made to this data series:

(a)   We have renamed ‘Energy Generated’ to now be labelled ‘Energy Generated (Estimate)’ to better reflect that this is an estimated value.

(b)  But more importantly, since this ‘Generators’ tab includes all units (and since consuming units do not “generate” energy), we have altered the series to be zero for any unit that is consuming – this mostly affects loads but also bi-directional units in the future.

InitialMW (Generation))

With respect to the (formerly named) ‘InitialMW’ data series :

(a)  This has has been renamed ‘InitialMW (Generation)’  to make it clearer; and importantly

(b)  Has been set as a 0MW data series for any Load.

Additionally, the (formerly known as) ‘FinalMW’ series:

(a)  has been renamed ‘Final MW (Generation)’.

(b) Has been set as a 0MW data series for any Load.

Coupled with the above …

InitialMW (Load)

We have added a new series ‘InitialMW (Load)’ which has is the SCADA snapshot at the start of each dispatch interval for the pre-IESS Loads:

(a)  Excluding Negawatt Units, as they are really supply-side units (despite the confusion of Tripwire #3)

(b)  But (unlike the clearer approach used for the new ‘Power’ series above, where we reverse the sign) we have not done this for InitialMW (Load) because it’s still named as for the field in the EMMS.

Because this is a legacy tab and will be retired in future, we did not implement a ‘FinalMW (Load)’ series.


Enhancement #5 = Simplifying the ‘Group By’ facets

As part of our push to simplify NEMreview to make life for our clients, we’ve simplified the number of facets available to group by (splitting onto separate tabs helps to make this possible).

In particular it’s worth noting 2 of the 6 facets that remain for this tab:

Enhancement #5a = A single ‘Type’

Anticipating the addition of hybrid units registered behind a single DUID (i.e. where production won’t be determinably coming from a particular fuel type) we have simplified to a singular classifier we’re calling ‘Type’ as follows:

 As shown in the screenshot above, there are currently eight values within this new category. We have implemented this new category in order to make it simpler for users to select aggregations of units, especially for storage units.

Please note that the new ‘Units (NEM)’ tab only includes units registered for the Energy Market. In a future release, we will introduce another new tab focused on the selection of Units registered for FCAS.

Enhancement #5b = Sorting by Dispatch Type

Where the user wishes to sort/filter further (e.g. by specifically excluding Loads in an aggregation) it would be possible to do this by using the ‘Dispatch Type’ filtering mechanism, as illustrated here:

Note with respect to the above that Bi-Directional Units will have their own (new) Dispatch Type.


What about NEMreview v6 (the installed software)?

For those clients who also still use NEMreview v6, we’ve also worked on preparing the software for IESS (without requiring a new installer).  Please contact us directly if you’d like to know more about what we have done here?