Energy Policy WA (EPWA) has published an Exposure Draft of Electricity System and Market (ESM) Amending Rules (Tranche 9) for consultation.
This includes proposed ESM Amending Rules to:
- address issues identified during the implementation of the new regime for Demand Side Programmes, which were consulted on in September 2025;
- address recent issues caused by incorrect meter data by ensuring that Rule Participants have the opportunity to disagree with changes to meter data submitted to AEMO after Settlement Adjustment Date 2;
- replace the default distribution method specified in section 9.21 of the ESM Rules and give the Economic Regulation Authority the responsibility for determining how all Civil Penalty Amounts are to be distributed; and
- amend the Individual Reserve Capacity Requirement (IRCR) calculation to remove a potential disincentive for retailers to offer IRCR reduction schemes to certain contestable customers.
On the 10 November 2025 EPWA published an addendum to the Exposure Draft of Electricity System and Market Amending Rules (Tranche 9) for consultation.
When developing the Exposure Draft, additional issues relating to the implementation of the new regime for Demand Side Programmes were identified for which rule changes could not be developed in time to be included in the Exposure Draft.
Stakeholders were advised in that Exposure Draft that proposed rule changes to address these issues will be finalized and provided separately.
The changes proposed in the addendum include:
- accounting for planned maintenance or other outages in the Relevant Demand;
- avoiding the risk of Market Participants losing more than 100% of the DSP Reserve Capacity Security in specific circumstance; and
- bringing forward the policy decision from the Reserve Capacity Mechanism Review to remove the concept of Non-Temperature Dependent Load (NTDL) by applying the same Ratio to the NTDLs and Temperature Dependent Loads.
Please refer to the addendum, by clicking the link below, to review these additional changes.
To see a summary of these and all other proposed changes, please refer to the Exposure Draft which can be found by clicking the link below.
EPWA held a Transformation Design and Operation Working Group (TDOWG) meeting on 12 November 2025 to discuss the Tranche 9 Exposure Draft.
The window for submitting feedback closed at 5:00pm (AWST) on 19 November 2025.
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