The System Security Forecast (SSF) is produced every two years and revised every six months if required.
Revisions to the SSF are required if changes to the power system materially affect the SSF. The 
SSF Guidelines [ pdf 666.68 KB ] document determines the purpose and principles of the SSF.
Our website has a dedicated page outlining thermal generation decommissioning analysis, including power system operation and security of supply. See Impact of thermal generator decommissioning.
The 2020 version of the System Security Forecast has incorporated the upper North Island (UNI) and upper South Island (USI) report sections within the respective North Island and South Island Backbone reports.
2020
The 2020 System Security Forecast based on new information known by the System Operator.
| Part A | Date |
|---|---|
| Executive Summary [ pdf 386.27 KB ] |
Dec 2020 |
| Part B | Date |
|---|---|
| Grid Configuration and Operations [ pdf 737.2 KB ] |
Dec 2020 |
| Part C | Date |
|---|---|
| Study Approach and Assumptions [ pdf 331.04 KB ] |
Dec 2020 |
| Part D | Date |
|---|---|
| Security Analysis North Island Grid Backbone and UNI Limits [ pdf 1.17 MB ] |
Dec 2020 |
| Security Analysis South Island Grid Backbone and USI Limits [ pdf 1.06 MB ] |
Dec 2020 |
| Security Analysis GZ01 Northland [ pdf 593.5 KB ] |
Dec 2020 |
| Security Analysis GZ02 Auckland [ pdf 617.75 KB ] |
Dec 2020 |
| Security Analysis GZ03 Hamilton [ pdf 680.57 KB ] |
Dec 2020 |
| Security Analysis GZ04 Edgecumbe [ pdf 704.17 KB ] |
Dec 2020 |
| Security Analysis GZ05 Hawkes Bay [ pdf 531.97 KB ] |
Dec 2020 |
| Security Analysis GZ06 Taranaki [ pdf 708.1 KB ] |
Dec 2020 |
| Security Analysis GZ07 Bunnythorpe [ pdf 780.76 KB ] |
Dec 2020 |
| Security Analysis GZ08 Wellington [ pdf 797.91 KB ] |
Dec 2020 |
| Security Analysis GZ09 Nelson Marlborough [ pdf 574.16 KB ] |
Dec 2020 |
| Security Analysis GZ 10 and 11 Christchurch and Canterbury [ pdf 593.29 KB ] |
Dec 2020 |
| Security Analysis GZ12 West Coast [ pdf 571.64 KB ] |
Dec 2020 |
| Security Analysis GZ13 Otago [ pdf 695.76 KB ] |
Dec 2020 |
| Security Analysis GZ14 Southland [ pdf 535.62 KB ] |
Dec 2020 |
| Part E | Date |
|---|---|
| Frequency Principal Performance Obligations [ pdf 369.7 KB ] |
Dec 2020 |
| Part F | Date |
|---|---|
| Dry Year Operational Issues [ pdf 432.46 KB ] |
Dec 2020 |
| Part G | Date |
|---|---|
| Resources (Maps, Site Codes, SLDs etc) [ pdf 1.04 MB ] |
Dec 2020 |
