Status update on Waratah Super Battery
Safety assessments were immediately conducted and as a precaution, a second High Voltage Transformer (HVT2) was de-energised. As part of regulatory requirements, the Australian Energy Market Operator (AEMO) was notified.
Throughout the incident and since, despite the loss of one transformer (HVT3) and the de-energising of another transformer (HVT2), the Waratah Super Battery has maintained its System Integrity Protection Scheme (SIPS) service requirements of 350MW, the interim commercial operating capacity, securely with its first transformer (HVT1). The battery continues to operate with available capacity of 350MW, and there has been no impact to the NSW electricity grid.
The two affected transformers are undergoing detailed engineering assessments and investigations as part of the Root Cause Analysis. This is a complex, multi-stage process involving physical inspection, testing and analysis.
- HVT3: We are unable to provide further details on the transformer failure until this analysis has concluded, and a determination is made, which may take several weeks or months.
- HVT2: Remains de-energised whilst it undergoes testing.
- HVT1: Has remained fully operational throughout.
This reduction in capacity is reflected in current AEMO forecasts as 0MW, as under the Australian Energy Regulator rules, Akaysha can only report capacity above the available SIPS service. The Waratah Super Battery is currently providing 350MW of SIPS service, and until the remaining capacity is confirmed, additional capacity (MW) cannot be included in AEMO’s forecast.
Upcoming planned outage
The Waratah Super Battery is scheduled to have a balance of plant shutdown from 20 November 2025 to 2 December 2025. This planned shutdown is part of routine maintenance and has been coordinated with AEMO and Transgrid for several months. During this time, the SIPS service will be unavailable, which was always anticipated by Transgrid, AEMO and EnergyCo.
Further updates
Akaysha will endeavour to promptly update the AEMO forecast as the project status changes and will continue to provide updates on the project program here, as this information becomes available.