Skip to main content

You might not have given much thought to WA’s electricity system - but with our changing energy landscape, it has never been more important to balance the supply and demand of our electricity system.


What is peak demand?

Peak demand refers to when electricity consumption is at its highest.

Here in WA, peak demand in our main electricity system is usually between 5pm and 9pm on the hottest days of the year. This is when extreme temperatures create a higher demand for electricity. 

In summer, for example, this is when many people arrive home from work or school and switch on their air conditioners, along with TVs, gaming consoles, lights and other appliances. The demand for electricity from the system spikes during these times. 

Why is peak demand a problem?

Peak demand impacts our whole electricity system. This means it impacts everyone across WA’s main electricity system: the South West Interconnected System (SWIS).

The impact of climate change: 

Climate change is causing more extreme weather conditions and hotter summers, which means that peak demand events are becoming more common. Dramatic temperature changes and sudden weather events can cause significant increases in electricity usage.

Growing demand for electricity:

 As our population grows, economic development increases and we use more air conditioning and more electric vehicles, it has been predicted that the state’s demand for electricity will increase.

How you can help with peak demand

When we’re all using energy at the same time, everyone can play a part to ensure there’s enough reliable power for when we need it.  

Making small changes to your electricity use means you could help reduce peak demand and potentially reduce your electricity costs. Here are some ways you could help reduce peak demand in hot conditions.

Set your aircon to 24 degrees, which still feels cool when it’s hot outside. It could also use less electricity compared to cranking your air con by setting it to a lower temperature.

On warm nights, try to open your house up to let in any breezes. Use fans to move the cooler air around.

Try to avoid using your pool pump during peak times. Check the manufacturer’s recommendations - you might be able to set your pump to run during the day before 5pm.

Set a timer to run your dishwasher or washing machine at lunchtime instead of at night. If you have solar, this means you’ll be using your solar energy too.

When it’s really hot, think about using less power-hungry appliances to cook dinner during peak times – for example, your BBQ or air-fryer instead of your oven.

Watch out for the drain of standby power. When you can, turn off your appliances and consoles at the wall so these don’t use power in standby mode.

Synergy’s role in supporting WA’s energy transition and system reliability

Everyone has a role to play in keeping our electricity system in balance. At Synergy, we’re working with the WA State Government, Western Power and other energy partners to reduce peak demand and increase the reliability of WA’s main electricity system.

We’re conducting innovative Virtual Power Plant trials such as VPP For Schools.

These trials explore how to help keep the electricity network stable by storing and sharing renewable energy between a school and local community.

Learn about VPP For Schools

We’re running exciting Virtual Power Plant pilots such as Project Symphony.

This involves combining and orchestrating Distributed Energy Resources (DER), like rooftop solar, batteries and selected household appliances to smooth out the supply and demand for electricity.

Learn about Project Symphony

We’re creating new electricity plans such as Midday Saver, a time-of-use tariff.

These plans can help eligible customers save on their electricity costs by shifting electricity consumption to off-peak time periods.

Explore Synergy Midday Saver

We’re building infrastructure to support renewable energy generation such as our large-scale Battery Energy Storage Systems or ‘big batteries’.

These store electricity from renewable generation sources during times of low demand and discharge it into the grid so this can be used by homes and businesses at times of peak demand.

Learn about our big batteries