On 5 November 2018 the Australian Energy Market Operator (AEMO) submitted a request to the Reliability Panel seeking to declare the risk to South Australia’s power system from destructive winds as a ‘protected event.’ Under the National Electricity Rules, the Panel can declare a protected event if it finds there are net economic benefits from AEMO taking certain pre-emptive actions to manage a particular risk.

AEMO has requested that the Panel declare as a protected event “the loss of multiple transmission elements causing generation disconnection in the South Australia region during forecast destructive wind conditions.” AEMO is currently managing this risk by constraining the amount of power being imported into South Australia from Victoria on the Heywood interconnector when destructive winds are forecast. However, AEMO believes there are more transparent and cost-effective ways to manage the risk, including by upgrading equipment and improving emergency schemes.  

Final determination

On 20 June 2019 the Panel published a final determination declaring a protected event in accordance with AEMO’s request. 

The Panel’s final determination supports AEMO’s recommended option for managing the protected event, which includes:
•    upgrading the existing system integrity protection scheme (SIPS) in South Australia
•    limiting imports across the Heywood interconnector during periods of forecast destructive wind conditions.

The Panel's declaration will provide a more cost-effective, fit-for-purpose mechanism for managing the risks associated with the protected event than current arrangements employed by AEMO, and
provide the market with more transparency about how AEMO would manage the protected event.

Background

The Commission’s final determination on the Emergency frequency control schemes rule in March 2017 introduced protected events as a category of non-credible contingency event for which there are net economic benefits from AEMO taking some pre-emptive action to manage, for example by purchasing frequency control ancillary services (FCAS), constraining generation dispatch or using Emergency Frequency Control Schemes (EFCS). 

Protected events may be declared by the Panel in response to a request from AEMO. This request is an outcome of AEMO’s 2018 Power System Frequency Risk Review. This is the first request for the declaration of a protected event which has been received by the Panel.