Discussion paper on the framework for power system strength

The Australian Energy Market Commission has begun a review into what is needed to keep the power system strong as new technologies are integrated into it.

The Commission has released a discussion paper into how to evolve the system strength frameworks needed for the stable operation of a rapidly transforming power system at the lowest cost to consumers.

System strength keeps the system stable. As well as keeping generators operating securely, system strength services help the system to ride out faults such as those that can follow a lightning strike on a power line. Keeping the system stable helps to avoid blackouts.

The discussion paper for the Investigation into system strength frameworks in the NEM builds on frameworks that were put in place in 2017 to ensure system security. Given the transition underway, it is timely to look at how we can adapt and evolve these frameworks given the significant amount of generation connecting to the system.

The Commission has engaged with a wide range of stakeholders on how these frameworks are operating in practice. This input has fed into this discussion paper.

We believe that while these frameworks have worked to keep the power system secure, they need to evolve. This is because of the pace of the power system transition and the need to support the rapid connection of large numbers of new non-synchronous generation such as wind and solar that is already underway. 

Since the frameworks were put in place, the industry has also developed a greater understanding of what system strength is and why it is needed. This is because Australia is at the forefront of operating power systems with large amounts of non-synchronous generation.

Such change has seen the need to constantly adapt thinking and practice in the area of systems strength. By 2040, this transition means that about 15GW of synchronous generation capacity such as coal and gas is expected to exit the market, with about 30-40GW of new non-synchronous generation to enter. 

Sufficient levels of system strength will be critical to keeping the system secure as this transition continues. And further investment in system strength could potentially boost the power system’s resilience and remove constraints on the network.

The focus of our work will be on how system strength services can be planned for, procured, priced and who pays for the service. 

All technologies and models are up for consideration in the investigation.  

The discussion paper outlines four broad models for how system strength can be provided, although a combination could be used. 

The issues and models explored by the Commission in the discussion paper will frame our ongoing talks with stakeholders and market bodies. 
The  discussion paper is part of the Energy Security Board (ESB)’s work program into system security, as well as AEMC’s ongoing work to make the power system more reliable and secure and will feed into the ESB’s 2025 market design project. The AEMC is working closely with the ESB, the Australian Energy Market Operator (AEMO) and the Australian Energy Regulator (AER) on these matters. 

The  Commission is aware of the additional pressures being placed on the energy sector as the nation responds to the fast moving COVID-19 threat. It is important in these times that Australia’s energy systems and markets are currently operating in a safe and secure state. The AEMC is working closely with the market bodies, the ESB, jurisdictions and energy industry on the implications of the current COVID-19 threat for implementation.