Transition Plan for System Security (TPSS)

The Transition Plan for System Security (TPSS) is an annual report focusing on maintaining power system security as the National Electricity Market (NEM) transitions towards lower emissions. It provides a structured approach for the energy sector to navigate key upcoming Transition Points – events that require material changes in the operational approach to managing power system security – over at least the next 10 years.

As of 1 December 2025, AEMO has combined all four system security reports together as the Transition Plan for System Security. Therefore, the Transition Plan is now where AEMO meets its reporting obligations of:

• The Transition Plan for System Security
• System Strength reporting
• Inertia reporting
• NSCAS gap declaration and reporting.

AEMO is responsible for maintaining and improving power system security in the National Electricity Market (NEM) and for providing a national, strategic perspective for electricity transmission planning and coordination, particularly during the NEM’s transition toward lower emissions. Under the National Electricity Rules, AEMO is required to annually publish the Transition Plan for System Security.