Transgrid has published a Supplementary Report to the Project Assessment Draft Report (PADR) for Maintaining system strength requirements in NSW. This Report offers an opportunity for consultation on these updates prior to the final step of the Regulatory Investment Test for Transmission (RIT-T) process, the Project Assessment Conclusions Report (PACR).
As the System Strength Service Provider (SSSP) for NSW, Transgrid has certain system strength obligations under the National Electricity Rule (NER):
- Clause 11.143.15 to address the system strength Shortfall declared by AEMO from 1 July 2025 to 1 December 2025 at Newcastle and Sydney West, and
- Section 5.1.14 to provide the minimum and efficient levels of system strength forecast by AEMO at each of the NSW system strength nodes from December 2025 into the future.
The results of the PADR assessment found that the preferred credible portfolio option involved fourteen synchronous condensers required by 2032/2033, modifications to or redispatch of synchronous generators, and 4.8 GW of grid-forming batteries.
Publication of the Supplementary Report represents an addendum to the PADR published in June 2024, capturing potential impacts of key developments that have occurred since the PADR modelling was finalised. Transgrid has modelled three sensitivities:
- Sensitivity 1: Revised retirement date of Eraring Power Station;
- Sensitivity 2: Inverter-based resource forecasts within AEMO’s Final 2024 ISP, including revised timing for the New England REZ.
The third sensitivity explores the costs and benefits of bringing forward the procurement of four synchronous condensers, by one year, from their identified date within the PADR between 2029/30 and 2031/32:
- Sensitivity 3: Increasing the robustness of the portfolio of system strength solutions by bringing forward the commissioning of synchronous condensers.
Transgrid welcomes written submissions on materials contained in this Supplementary Report. Submissions are due on 15 November 2024 to regulatory.consultation@transgrid.com.au.
In accordance with the requirements of the National Electricity Rules, a summary of the Supplementary PADR is made available on the AEMO website. The Supplementary Report to the PADR can be found on Transgrid’s website.