The System Security Forecast (SSF) identifies risks to our ability to achieve our Principal Performance Obligations over the next three years. It provides information to enable market participants to understand security risks and how these will be managed.
We produce the SSF every two years and provide updates every six months if there are material changes to the power system. The SSF Guidelines determine the purpose and principles of the SSF.
In addition to the SSF, we produce other security assessments that participants may find valuable. These include the Security of Supply Annual Assessment, the New Zealand Generation Balance and other updates on the market and system security such as Electricity Risk Curves. As Grid Owner, Transpower also publishes Transmission Planning Report.
Process for scoping the System Security Forecast Review
The following process was adopted in scoping the 2024 SSF and will be applied to subsequent forecasts. It provides a process for identifying and prioritising emerging issues for inclusion in the assessment.
2024 System Security Forecast
The risks identified for the 2024 SSF are as follows. The SSF and related documents can be found below, other documents relating to the SSF are available in the resources section of the website.
| Report | Contents | Date |
|---|---|---|
|
N - 1 Thermal and Voltage Study.pdf
(PDF 3.16 MB)
|
| Minor update Dec 2024 |
|
Transient Rotor Angle Stability Study.pdf
(PDF 1.43 MB)
(New for 2024 SSF) | This report is a study of transient rotor angle stability (TRAS), which refers to the ability of a synchronous machine to remain synchronised under normal operating conditions and to regain synchronism after a disturbance. Our study includes an initial ‘screening’ exercise to understand potential TRAS risks across the full system and recommends further assessment, discussions with asset owners and mitigation strategies. | Dec 2024 |
|
System Security Forecast Summary Report.pdf
(PDF 361.97 KB)
(New for 2024 SSF) | This report provides a view of the anticipated challenges and opportunities in maintaining a secure power grid. This forecast is crucial for guiding the System Operator’s strategic planning and operational decisions, ensuring that we are prepared to meet the evolving demands of our energy landscape. | Dec 2024 |
|
Appendix A Grid Configuration.pdf
(PDF 2.2 MB)
| A summary of the Grid configuration and general assumptions used in the SSF | Dec 2024 |
|
Appendix B Study Methodology.pdf
(PDF 517.41 KB)
| A summary of the methodology used to assess security in the SSF N-1 Thermal and Voltage Study | Jul 2024 |
The SSF has been refocused to assess the new and emerging security risks caused by the changing energy landscape, particularly the introduction of more inverter-based resources instead of conventional synchronous generators. The SSF will continue to study the N-1 contingency impacts to system security, but the outage (N-1-1) studies will no longer be included in the SSF as the impact of planned outages and how the System Operator studies them are captured by internal processes. The impact of outages will be studied separately and released on the Outage planning page in 2025.
2022 System Security Forecast
The 2022 SSF will be available until the completion of the N-1-1 outage study in 2025.
- 2022 SSF Documents
Part Name Date A Part A Executive Summary.pdf (PDF 386.89 KB)Dec 2022 B Part B Grid Configuration and Operations.pdf (PDF 762.19 KB)Dec 2023 C Part C Study Approach.pdf (PDF 329.53 KB)Dec 2022 D Part D NI Backbone.pdf (PDF 1.38 MB)Dec 2022 D Part D SI Backbone.pdf (PDF 1.67 MB)Jun 2023 D Part D GZ01 Northland.pdf (PDF 600.11 KB)Dec 2022 D Part D GZ02 Auckland.pdf (PDF 795.61 KB)Dec 2022 D Part D GZ03 Hamilton.pdf (PDF 741.02 KB)Jun 2023 D Part D GZ04 Edgecumbe.pdf (PDF 683.13 KB)Dec 2023 D Part D GZ05 Hawkes Bay.pdf (PDF 541.51 KB)Dec 2022 D Part D GZ06 Taranaki.pdf (PDF 607.95 KB)Dec 2022 D Part D GZ07 Bunnythorpe.pdf (PDF 698.55 KB)Dec 2022 D Part D GZ08 Wellington.pdf (PDF 808.57 KB)Dec 2022 D Part D GZ09 Nelson Marlborough.pdf (PDF 728.11 KB)Dec 2022 D Part D GZ10 and 11 Christchurch and Canterbury.pdf (PDF 715.94 KB)Dec 2022 D Part D GZ12 West Coast.pdf (PDF 605.59 KB)Dec 2022 D Part D GZ13 Otago.pdf (PDF 778.72 KB)Jun 2023 D Part D GZ14 Southland.pdf (PDF 611.51 KB)Dec 2022 E Dec 2022 F Part F Dry Year.pdf (PDF 397.12 KB)Dec 2022 G Part G Resources.pdf (PDF 1.44 MB)Dec 2022