The Australian Energy Market Operator has published its Quarterly Energy Dynamics report for the June 2026 quarter. Two findings in it bear directly on the Western Australian market: household battery capacity in the Wholesale Electricity Market grew by more than a third in three months, and the average wholesale energy price reached the highest level recorded in that market.
Household storage in Western Australia
Drawing on Clean Energy Regulator data current to 30 June 2026, AEMO records that household storage capacity in the Wholesale Electricity Market increased by 288 megawatt hours over the quarter, a rise of 39 per cent, reaching 1,027 MWh. The number of installations rose by 11,823 over the same period, an increase of 33 per cent, taking the state past 47,000 household battery systems.
AEMO attributes the growth to two programs running together: the federal Cheaper Home Batteries Program and the WA Residential Battery Scheme.
The report also notes the changes that took effect on 1 May 2026 for new and upgraded solar and battery systems in the South West Interconnected System, including the increased inverter size limit of 30 kVA for standard connections, as supporting continued uptake.
Capacity grew faster than the installation count. This suggests the systems added during the quarter were, on average, larger than the systems already recorded in the field.
AEMO reports the 288 MWh quarterly increase and 1,027 MWh closing capacity. The 739 MWh opening value is derived by subtracting the reported increase from the reported closing value.
Data table
| Measure | Value | Status |
|---|---|---|
| Quarter opening capacity | 739 MWh | Derived |
| Capacity added | 288 MWh | Reported |
| Quarter closing capacity | 1,027 MWh | Reported |
| Quarterly growth | 39% | Reported |
A record wholesale price
The average real-time energy price in the Wholesale Electricity Market rose by $27.41/MWh year on year to $117.87/MWh for the quarter. AEMO describes this as a new record for that market.
AEMO identifies a combination of reduced lower-cost supply and higher operational demand. Wind and coal-fired generation fell by a combined 191 MW year on year, which increased reliance on higher-cost gas generation. Coal generation dropped 137 MW, reflecting planned and forced outages and the retirement of Muja C Unit 6 in the June 2025 quarter. Wind generation fell 54 MW, affected by outages associated with the Warradarge Wind Farm expansion and weaker wind conditions.
Renewable generation accounted for 32.0 per cent of the Wholesale Electricity Market fuel mix for the quarter, down from 33.6 per cent a year earlier. Gas increased its share of the fuel mix by 8.30 percentage points.
Underlying demand rose 1.6 per cent year on year on lower temperatures and higher heating demand. Growth in distributed photovoltaic output of 3.4 per cent partly offset that increase.
These are wholesale market figures. They describe pricing in the real-time market, not what a household or business pays on a retail bill, and the two do not move together on a quarterly basis.
Battery households cut evening peak grid draw by 73 per cent
The same report contains a measurement of household battery behaviour that has not been available at this scale before. AEMO compared two samples of 10,000 households each, drawn from metering data: detached dwellings with rooftop solar below 20 kW, and comparable dwellings with both solar and a battery installed between 1 July and 1 December 2025.
Across the evening peak, defined in the report as 1600 to 2100 hrs, households with a battery recorded average net grid imports 0.7 kW lower than solar-only households, a reduction of 73 per cent. Battery households also moved to net export later in the morning, consistent with charging before exporting surplus generation, and continued exporting for longer through the evening.
Two qualifications matter when this figure is repeated.
The first is geographic. This comparison covers the National Electricity Market, and Western Australia sits outside it on the South West Interconnected System.
The published range shows the effect varies with tariff structure, climate and system sizing. A Western Australian equivalent has not been published.
The second is units. The measurement is average power drawn at a point in time, expressed in kilowatts. It is not a measure of total energy consumed over the quarter, and it does not describe a bill outcome.
Fleet data shows direction, not what a property should install
The figures establish that batteries are being installed in Western Australia at a materially faster rate than a year ago. AEMO's National Electricity Market sample also shows batteries measurably reducing grid draw during the evening peak. Both are matters of record, but they describe separate markets.
They do not establish what any particular property should install. That assessment continues to rest on site data: consumption and generation profiles, import and export tariffs, usable capacity, backup requirements, connection limits and the condition of the existing installation. Quarterly market data describes direction across a fleet. It is not a substitute for the site-level work that determines whether a given system is appropriate.
For McKercher Corporation, the same discipline applies here as to the GenCost 2025-26 findings. Public market evidence is used to understand where the market is moving, while Perth Solar Warehouse and PSW Energy assess each project within their respective retail and installation responsibilities.
Primary references
- AEMO Quarterly Energy Dynamics (opens in a new tab), Q2 2026, especially section 2.1.2 on consumer energy resources and sections 4.1 and 4.2 on the Wholesale Electricity Market
- Clean Energy Regulator small-scale installation postcode data (opens in a new tab), current to 30 June 2026
Clean Energy Regulator installation figures for a recent period continue to rise after publication, because certificate creation is permitted for 12 months after installation.
