Your guide to emergency solar management: ESM low load events and testing

The WA State Government introduced emergency solar management (ESM) to help keep the electricity system stable and support the continued installation of rooftop solar PV systems. ESM is the ability to remotely turn off (and turn back on again) the capability of solar PV systems to generate electricity for:

• ESM Events: Low load events tend to happen in the months leading in and out of spring and autumn. Changing seasons and temperatures can have an impact on demand for electricity in the network and how much electricity is generated by solar PV systems and used in your home throughout the day (for example for heating and cooling).
  
  
• Event Tests: Event tests also need to be conducted for compliance purposes to make sure that any rooftop solar PV systems subject to ESM requirements can be remotely managed. This also ensures we are ready for ESM low load events. We do our best to make sure that any testing is as unobtrusive as possible.

Here are some important things to know:

• ESM requirements apply to rooftops solar PV systems installed or upgraded after 14 February 2022 with an inverter capacity of 5kW or less. 
• Information on ESM Events (‘low load event’) and Event Tests from 1 January 2023 is available on this page. 
• Your solar PV system may have participated in ESM testing before this date. 
• Multiple ESM events may occur depending on the requirements of the requested event. For example, different groups of systems may be directed to respond to an event at different times on the same day to ensure that in emergency conditions, widespread electricity interruptions in the grid can be mitigated and that the ESM event was successful in supporting this.   

In the table below, you can see the dates and times solar PV systems subject to ESM requirements have been remotely managed in response to an ESM low load event or for testing and compliance purposes. Not all solar PV systems subject to ESM requirements are affected by an ESM Event or ESM Test. 

Testing is performed once a month. Sometimes tests may appear twice in the table due to the way signals are sent to solar systems. 

ESM information on this page will be updated within 24 hours following an ESM Event or Event Test. To find out which ESM Events and ESM Tests affected your solar PV system, log into My Account and view the ESM Solar tab.