Australia’s recent heatwave was felt far beyond the energy sector. For many communities, the focus was on getting through extreme temperatures, managing bushfire risk and keeping people safe. Infrastructure and essential services were under pressure at the same time, adding to the strain.

Events like this are becoming more common. Longer and more intense heat periods are now part of Australia’s climate reality, and they place increasing pressure on systems we rely on every day, including energy supply.

During the heatwave, electricity demand rose sharply across multiple regions of the National Electricity Market (NEM). From a system point of view, the grid held up well. Supply was maintained, major outages were avoided and the system continued to operate as intended.

This occurred alongside severe bushfire conditions in several areas. Fires can limit how electricity moves across the network, affect generation availability and add operational risk at exactly the wrong time. That the system continued to function safely reflects the level of coordination and care required during extreme conditions.

What demand looked like this time

High temperatures drove increased electricity use across homes, businesses and industrial sites, particularly as cooling loads climbed. In past heatwaves, this level of demand would often have placed sustained pressure on the system throughout the day.

This time, the shape of demand looked different.

During daylight hours, rooftop and large-scale solar generation made a meaningful contribution to meeting increased demand. Strong solar output reduced the amount of electricity that needed to be supplied from other sources during the hottest part of the day.

In several regions, this helped keep daytime conditions more balanced and, at times, resulted in periods where available supply exceeded demand. Compared to earlier summers, where daytime demand often coincided with the tightest system conditions, this marks a noticeable shift.

Pressure still builds later in the day

As the afternoon wore on, solar output began to fall, but temperatures and demand remained high. During these late afternoon and evening hours, the system leaned more heavily on dispatchable generation and interconnector flows.

These periods remain the most sensitive during heat events. They highlight where the system still needs the most support once the sun goes down and demand stays elevated.

Where battery storage fits in

As battery storage continues to be added to the system, it has the potential to play a growing role in managing this transition from day to night. Batteries can store excess energy generated during the middle of the day and supply it back to the system later, when demand remains high but solar output has dropped.

Battery deployment is still evolving, and its impact will build over time. But as capacity increases, it is likely to influence how the system manages peak demand periods, particularly during extreme weather events like heatwaves.

What this shows

Recent conditions highlight how the energy system is changing. Demand is still highly sensitive to heat, but the way that demand is met is evolving.

Daytime supply is increasingly shaped by solar generation, while late afternoon and evening periods continue to rely on dispatchable sources. As technologies like battery storage become more widespread, they are expected to play a larger role in bridging that gap.

Understanding how these pieces fit together is becoming an important part of understanding how the energy system responds during extreme conditions.

At Utilizer, we focus on providing clear, practical context around these changes, helping organisations make sense of how the energy market is evolving. Our energy experts are always ready to help, reach out anytime for a chat.