Skip to content

Review of method used to assign capacity to intermittent generators 2018

Every three years, the ERA reviews the method used to certify capacity for intermittent generators, such as wind and solar farms. As these generators have less control over their output, the capacity certification method acknowledges this variability.

In March 2019, the ERA completed its review of the method for the capacity valuation of renewable energy technologies in the Wholesale Electricity Market Rules - referred to as the relevant level method. After receiving feedback from stakeholders, the ERA recommended changing the method.

The market rules require the ERA to progress recommendations from its review as a rule change proposal. While any proposed rule change is in development, the current relevant level method will continue to apply. In accordance with clause 4.11.3C of the Market Rules the ERA has determined the following values for the parameters K and U in step 17 of the current relevant level method. After the approval and implementation of the proposed rule change these parameters will no longer apply.

Reserve capacity cycle Capacity year K value U value
2019 2021/22 0.000 0.635
2020 2022/23 0.000 0.635
2021 2023/24 0.000 0.635
2022 forward 2024/25 forward
0.000  0.635

Development of the rule change proposal

The ERA has developed a rule change proposal and submitted it to the Rule Change Panel, after a delay to address possible interactions between the proposal relevant level method and Energy Policy WA's proposed amendments for the constrained network access regime.

The ERA presented a preliminary rule change proposal to the Market Advisory Committee on 17 November 2020 seeking feedback. The ERA received one written submission on the preliminary rule change proposal, from Alinta Energy. This submission is published below.

ERA papers

The ERA published a draft report on 21 December 2018 to seek feedback from market participants and interested parties on the Relevant Level Methodology. The consultation period closed on Monday, 18 February 2019. The ERA published a final report on 31 March 2019.

Date Document File type
31-Mar-19 Final report Adobe PDF 1.3 MB
31-Mar-19 Technical appendix to the final report Adobe PDF 1.2 MB
21-Dec-18 Draft report Adobe PDF 935 kB
21-Dec-18 Technical appendix to the draft report Adobe PDF 1.2 MB


Public submissions

We received eight submissions in response to our draft report, and one submission in response to the preliminary rule change proposal. These submissions are available in the table below.

Date Document File type
17-Dec-20 Alinta Energy - Preliminary rule change proposal  Adobe PDF 95 kB
26-Feb-19 SkyFarming Pty Ltd  Adobe PDF 33 kB
19-Feb-19 Australian Energy Market Operator (AEMO)  Adobe PDF 448 kB
19-Feb-19  Alinta Energy  Adobe PDF 186 kB
19-Feb-19  Community Electricity  Adobe PDF 237 kB
Infrastructure Capital Group  Adobe PDF 92 kB
Noel Schubert - Individual  Adobe PDF 708 kB
19-Feb-19 Synergy  Adobe PDF 7.7 MB
Timothy Edwards - Individual                Adobe PDF 21 kB

Progress updates

The ERA Secretariat has established a working group to assist with the review. Regular status updates will be made public here as well as any presentations to the working group or to the Market Advisory Committee. These documents are working notes only and do not represent the official views of the ERA.

Page last updated: 15 Feb 2023