The State's first large-scale battery storage system in Kwinana is now complete.
The 100 megawatt/200 megawatt-hour battery can store enough energy in reserve to power 160,000 homes for up to two hours.
Battery energy storage systems absorb excess energy from rooftop solar when the sun is shining and release it in the evening, when demand is at its peak.
The system, which involved more than 200 jobs in construction, will now undergo a series of charge and discharge tests before entering the network later this year.
The State Government has also allocated $2.3 billion towards two new battery energy storage systems in the 2023-24 State Budget, including a second, larger system at the Kwinana site.
The proposed big battery will provide 200 megawatts (MW) of capacity with 800 megawatt hours - four times the energy storage of stage one.
A further battery system will be developed in Collie, which will be one of the biggest battery systems in the world - providing around 500 MW for up to four hours.
The second Kwinana big battery is expected to be operational by late 2024.
"My Government is taking action to deliver a cleaner, affordable and reliable energy transition for Western Australia," Premier Mark McGowan said.
"Battery storage systems will be critical to our energy future, allowing us to harness our rooftop solar resources to meet power needs during peak times."

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