Emergency backstop mechanism

Requirements for new and replacement rooftop solar and battery storage systems of 10 kilovolt amperes and over.

Adapting to Queensland’s changing electricity system

Queensland is a world leader in rooftop solar PV (photovoltaic) uptake and is naturally positioned to continue this trend.

As more renewable energy is integrated into the grid, we need to ensure the electricity system remains secure so all Queenslanders can continue to depend on it.

To enable individual customers to feed their solar energy into the grid at growing rates, the Queensland Government is introducing an additional safeguard that will maintain electricity system strength if there is a threat to the safe delivery of power to customers.

Introducing the emergency backstop mechanism

All new and some replacement inverter energy systems (like rooftop solar PV), with aggregated capacity of 10 kilovolt amperes (kVA) and above are required to be fitted with a generation signalling device. Some exclusions apply to the requirement – including inverter energy systems where the inverter is solely supplied by a battery.

This device enables Ergon Energy and Energex to reduce the risk of state-wide power outages by switching these systems off for a short time in an energy emergency situation.

The ‘emergency backstop mechanism’ will be activated only as a last resort at the direction of the Australian Energy Market Operator (AEMO). The decision will be in line with AEMO’s minimum system load market notification framework, which sets out pre-agreed steps and actions that AEMO can issue to electricity networks in response to a declared energy emergency.

This is an important step in supporting Queensland’s transition to a more coordinated electricity system, as it will:

allow more households and businesses to enjoy the benefits of rooftop solar in the future
help Queensland reach its 50% renewable energy target by 2030
support the uptake of technologies like battery storage and electric vehicles.

Electricity networks operate at their best when supply aligns with customer demand. When solar generation is high and demand falls too low, it poses a risk to system security.

This makes it more challenging for Queensland’s network service providers (Powerlink, Energex and Ergon Energy) to supply power to Queensland homes and businesses safely and reliably.

When this occurs, it is called a ‘minimum system load’ event. The introduction of the emergency backstop mechanism will mean our distribution networks can continue to connect solar at the same impressive rates as recent years, without affecting the safe and reliable supply of power to all customers.

National recommendations

The adoption of an emergency backstop in Queensland is consistent with safeguards that other jurisdictions are implementing.

In October 2021, the Energy National Cabinet Reform Committee agreed to a recommendation by the Energy Security Board that emergency backstop measures be adopted as an immediate reform to support system security during times of minimum system load.

In response to this recommendation, the Queensland Government has implemented an emergency backstop mechanism, tailored for Queensland, that will safeguard the continued stability of the grid and support the continued uptake of renewables across the state.

New solar PV connection requirements

All new and some replacement inverter energy systems (like rooftop solar PV), with aggregated capacity of 10kVA and above are required to be fitted with a generation signalling device to connect to the grid.

The generation signalling device is activated via Energy Queensland’s audio frequency load control (AFLC) network. The AFLC network allows for a signal to be transmitted across the state’s electricity system. Exclusions apply to the requirement to install a generating signalling device – including where inverter energy systems are installed at a location that is not serviced by the AFLC network.

AFLC has been utilised by Queenslanders for almost 70 years and is proven to support system security. Energex and Ergon Energy also use the AFLC network to operate economy tariffs (mainly for hot water load control) and the PeakSmart program, which dials down air conditioners during peak demand events.

In an energy emergency situation, AEMO would direct Energex and Ergon Energy to turn inverter energy systems off (via the AFLC network), preventing any generation, self-consumption or export for the duration of the event to maintain security of the grid. Some exclusions apply – including inverter energy systems where the inverter is solely supplied by a battery.

Find out more about how AEMO manages minimum system load risk (PDF, 201KB) and lets the market know when it needs to act.

Consultation and commencement

In September 2022, Ergon Energy Network and Energex carried out industry consultation on the emergency backstop mechanism through a consultation paper and webinar, receiving feedback from a wide range of stakeholders.

After considering the feedback, it was determined the emergency backstop mechanism would apply from 6 February 2023, to support installer and equipment manufacturer preparations.

Visit the Energex or Ergon Energy Networks websites for more information about their response to consultation feedback.

Information for customers

The emergency backstop mechanism will apply only to new and some replacement inverter energy systems (like rooftop solar PV), with aggregated capacity of 10kVA and above. These are typically installed by large residential and commercial/industrial customers.

Customers will pay for the generation signalling device as part of the system and installation costs. Customers looking to install rooftop solar and battery systems should always source quotes from reputable suppliers (see the Clean Energy Council website).

Information for solar retailers and installers

The requirement for new and some replacement inverter energy systems (like rooftop solar), with aggregated capacity of 10kVA and above to be fitted with a generation signalling device will be reflected in upcoming changes to the Queensland electricity connection manual (PDF, 21.57MB) and connections standards:

Solar retailers and installers should contact Ergon Energy or Energex for further information about accessing and installing the generation signalling devices.

Other measures to strengthen system security

The Queensland Government is working closely with AEMO, Powerlink and Energy Queensland to develop a range of solutions aimed at strengthening system security and supporting the ongoing integration of renewable energy technologies over the medium to long term.

This includes:

the staged rollout of dynamic connections and dynamic operating envelopes (see the Talking Energy website)
large-scale energy storage on the transmission and distribution networks (i.e. big batteries)
support for electric vehicles and electrification of industries
pumped hydro (e.g. the Borumba Dam Pumped Hydro Project)
tariff reform
economic development supporting daytime demand growth.

This work continues the shift towards a more flexible and integrated electricity grid where customers can continue to:

install the system they want
save money on their power bills
do their bit for the environment
support other customers who want to do the same.

Contacts

Department of Energy and Climate (general enquiries) - 13 43 87
Energex (installer enquiries in South East Queensland) - 13 12 53
Ergon (installer enquires in regional Queensland) - 13 74 66

Last updated: 05 September 2024