In early 2023, the Coordinator of Energy undertook a review of the supplementary capacity provisions of section 4.24 of the Wholesale Electricity Market Rules (WEM Rules).
Clause 4.24.19 of the WEM Rules requires that after each call for tenders for supplementary capacity or otherwise acquiring Eligible Services the Coordinator of Energy must review the supplementary capacity provisions and undertake a public consultation process on the outcomes of the review.
The Review was undertaken in 2 stages, with both completed in mid 2023:
Stage 1 assessed the effectiveness of the supplementary capacity procurement process.
Stage 2 assessed the performance of the procured supplementary capacity services.
Stage 1 Consultation Paper was published on 7 March 2023. The paper sets out the outcomes of Stage 1 of the review.
A Transformation Design and Operation Working Group (TDOWG) meeting to discuss the proposals in the Stage 1 Consultation Paper was held on 15 March 2023.
On 28 April 2023, Energy Policy WA published the Stage 1 Information Paper that presented the outcome of Stage 1, including:
feedback from stakeholders and the Coordinator’s responses;
the Coordinator’s decisions on the proposals outlined in the Consultation Paper; and
the Amending Rules approved by the Minister
The Wholesale Electricity Market Amendment (Supplementary Capacity) Rules 2023, incorporating the outcome of Stage 1, were approved by the Minister for Energy and a notice was published in the ºÚÁÏÕýÄÜÁ¿ Gazette on Friday 28 April 2023.
Stage 2 Consultation Paper was published on 7 June 2023. The paper sets out the outcomes of Stage 2 of the review.
A TDOWG meeting to discuss the proposals in the consultation paper was held on 15 June 2023.
On 18 July 2023, Energy Policy WA published the Stage 2 Information Paper that presented the outcome of Stage 2, including: 
feedback from stakeholders and the Coordinator’s responses; 
the Coordinator’s decisions on the proposals outlined in the Consultation Paper; and 
the Amending Rules approved by the Minister  
The Wholesale Electricity Market Amendment (Supplementary Capacity No. 2) Rules 2023, incorporating the outcome of Stage 2, were approved by the Minister for Energy and a notice was published in the ºÚÁÏÕýÄÜÁ¿ Gazette on Tuesday, 18 July 2023.
