Western Australia’s main power system is in a stronger position than previously forecast, driven by the adoption of home batteries and large-scale storage projects that will ensure grid reliability for the next three years.
According to the Australian Energy Market Operator’s (AEMO) 2026 Wholesale Electricity Market (WEM) Electricity Statement of Opportunities, the South West Interconnected System (SWIS) holds sufficient capacity to comfortably meet demand until at least 2028–29.
The updated 10-year outlook represents an upgrade from last year’s assessment, reporting a comfortable 347-megawatt capacity surplus for the 2028–29 period against a peak requirement of 6,323 megawatts.
AEMO Executive General Manager Western Australia, Kirsten Rose, credited coordinated policy and rapid consumer adoption for the turnaround.
“The near-term outlook for the SWIS has improved, and reliability targets are expected to be met over the next three years,” Rose said.
“This improved outlook has been largely driven by strong investment alongside government-led initiatives.”
A driver is the rise of virtual power plants (VPPs), networks of coordinated household solar and battery systems. These distributed resources are forecast to slash evening peak grid demand by 200 megawatts by 2028–29.
The uptake of distributed energy resources including household batteries has also contributed to the positive near-term outlook.
“Consumer investment in rooftop solar and household batteries is playing an increasingly critical role in the power system,” Rose said.
Concurrently, a robust commercial pipeline will see more than 1,000 megawatts of new large-scale generation and storage progressively stream online by 2030–31, aided by the Federal Capacity Investment Scheme.
Grid stability was further secured by a timeline extension for the Griffin Coal Mine, keeping the Bluewaters Power Station operational until 2031.
However, energy authorities warn against complacency over the longer term. As WA’s population grows and electrification accelerates, total system demand is projected to soar by more than 50 per cent over the decade.
With 1,661 megawatts of older thermal generators scheduled to progressively retire by 2035–36, AEMO stresses that sustained, well-timed investment in replacement renewables and transmission infrastructure remains vital to avoid shortfalls in the 2030s.
“The project pipeline is clearly strong, but it remains critical new generation and storage capacity is delivered on time, alongside planned transmission network augmentations,” Rose said.