The growth in renewables including rooftop solar — and energy storage — continue to put downward pressure on wholesale electricity prices; even as the shift to electrification accelerates. Whether/when we’ll see that flow on to household electricity bills and by how much is another matter.
How Did Wholesale Electricity Prices Track In Q3, 2025?
In its Quarterly Energy Dynamics Q3 2025 report released last week, the Australian Energy Market Operator (AEMO) indicates wholesale electricity prices for the National Electricity Market (NEM)1 averaged $87 per megawatt hour (MWh) in the September quarter, a fall of 27% year-on-year and 38% since Q2 2025.
NEM State-By-State Scorecard
Comparing year-on-year Q3 average wholesale spot prices:
- Queensland: $72/MWh (-28%)
- Victoria: $77/MWh (-26%)
- New South Wales: $90/MWh (-25%)
- Tasmania $91/MWh (-18%)
- South Australia $104/MWh (-34%)
The AEMO says higher renewable energy output and less market volatility contributed to the decreases.
It’s worth noting that all NEM states saw significant *increases* in Q3 last year, averaging $119/MWh; up $56/MWh (+88%) on Q3 2023. The increase for that period was driven by factors including higher average and peak operational demands, reduced hydro generation, and network outages limiting interconnector flows.
Single Day Drags Down SA Performance
While coming in at the tail end of the pack in Q3 2025, almost $19/MWh of the $104/MWh average for South Australia was due to a single day.
On July 2, 2025, South Australia experienced sky-high wholesale electricity prices during the morning and evening peak periods. Wind generation was low, and imports into South Australia were restricted by transmission limitations on the Heywood interconnector. There were 68 intervals going above $3,000/MWh on that day, including seven intervals above a whopping $13,000/MWh — more than $13 per *kilowatt-hour*.
What About WA?
As with the Northern Territory, Western Australia isn’t part of the NEM, but the AEMO includes some WA reporting.
Q3 2025 wholesale prices reached an average of $101.76/MWh in Western Australia, an increase of $21.61/MWh (+27%) on Q3 2024.
“This reflects the large increase in operational demand across the quarter and changes to the FCESS Uplift framework resulting in fewer committed facilities during the middle of the day,” says the AEMO.
A graph with price movements for all the states:
Electricity Demand Up (And Down)
Demand from grid-scale generation increased 2.3% in Q3 2025 compared to Q3 2024, to average 22,323 megawatts (MW); while underlying demand (grid-scale demand and rooftop solar) was up 3.2% to a new Q3 high of 25,154 MW, says AEMO.
“The electricity demand growth was driven by colder weather, alongside broader trends of increasing electrification of homes, adoption of electric vehicles, and rising data centre consumption,” said AEMO’s Violette Mouchaileh.
But growing levels of renewables and energy storage helped keep a lid on things.
“Partially offsetting demand growth is an increasing wave of new generation and storage projects connecting to the NEM, with 1,600 MW progressing through commissioning to reach full output in Q3,” the AEMO states.
New minimum demand records for the NEM were also set during the period, thanks in part to 11% growth in rooftop solar output, and 16% more wind and grid-scale solar output.
Will Pricey Power Bills Continue?
The AEMO’s report was certainly good news, but those hoping this will soon flow on to a big reduction in their electricity bills after recent price rises may be disappointed.
Wholesale electricity costs only make up around 35% of a residential electricity bill. Then there are network (~39%), environmental (~7%) and retail/other costs (~10%), plus of course an electricity retailer margin (~6%).
Based on a $500 quarterly electricity bill on average, the wholesale cost would comprise around $175. A fall of 27% in those costs works out to be $47; less than 10% of the overall bill. Still, it’s certainly better than a poke in the eye with a sharp stick *if* that reduction was passed on.
Federal energy bill rebates have taken some of the sting out of big electricity bills in recent times. But those finish up as the year draws to a close, and there’s no indication as yet they will continue.
Compare Power Plans, Install Solar (And Batteries)
As the Australian Competition and Consumer Commission highlighted last year, it can really pay to compare electricity plans to ensure you’re not being gouged (too much).
But for really tiny electricity bills, installing solar panels if you have a suitable rooftop (and control of it) is a slam-dunk move. For Australian households with solar power systems already installed wanting to minimise mains grid consumption in the early mornings, late afternoons, evenings and when weather is unfavourable, the Cheaper Home Batteries program has put residential energy storage within the grasp of many more households; slashing costs and simple payback times.
Home batteries are being installed at a rapid rate thanks to the scheme: ~ 108,000 at last count (Saturday) since the scheme formally launched in July. The benefits of these batteries will go beyond those provided to their owners; including putting additional downward pressure on peak electricity prices through reduced mains grid demand.
See how much you could save with solar (and batteries) here; and by adding a battery to an existing system here.
Footnotes
- The NEM is comprised of Queensland, New South Wales (including the Australian Capital Territory), South Australia, Victoria, and Tasmania. ↩
About Michael Bloch
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Amber electric claim it give theirs customer whole sell price, qnd they also claim feedin can be negative price if the grid have a lot solar electric, but is that the case or they just charge more? I save a lot more money with other electric company than amber with solar and battery at home
Thank you, Michael for providing some real numbers, too often missing in the ongoing media kerfuffle over electricity costs. Fossil fuel pushers seem to miss no opportunity to blame coal outages and network upgrade costs on renewable generation, despite that being the only negative price driver in sight.
Later in the energy transition, when fuel costs fall to zero, as we actually reach the 21st century, to power our car with a star, it’ll be clear that distributed energy abundance is economically democratising. (That’s why fossil fuel barons hate it.)
But why do some folk still try to bring on the climatic zombie apocalypse by buying fossil-only so-called HEVs, which are in no way EVs – but HICEs in sheep’s clothing, farting tonnes of CO₂ wherever they go?
The double maintenance burden of two fossil-powered propulsion systems will be a pain, but too late for many to learn, it seems.
Slow learners are inevitable, but are we to cook due to those who do not learn at all?
Less gas- & coal-fired generators in the NEM mix leads to cheaper wholesale electricity prices.
https://reneweconomy.com.au/gas-and-high-coal-penetration-are-the-drivers-of-expensive-volatile-power-prices/
Wait, so Queensland coal is providing the lowest prices while SA wind and gas is the highest? That’s interesting!!! Odd that Tasmanian hydro is so expensive though. Shouldn’t rainwater be the cheapest option, at least in Tasmania?
Of course if wholesale power prices only comprise a third of the bill, and grid costs comprise another third plus, we probably ought to be paying more a lot more attention to the cost of wires, widgets, and maintenance. By my rough calculation the wholesale price is actually LESS THAN a quarter of my retail price. That means either the proportions are way off, there’s a huge ‘error margin’ in retail prices to allow for significant swing, or there’s another cost not listed e.g. 30% taxes. No I don’t believe Australia has taxes that high on power, but some other nations’ power bills are half or more taxation.
Hi John,
Over the last three days averages;
Queensland black coal is valued at $72.56, wind is $68.97 & rooftop solar is $5.43
In SA there is no coal (aside from some small percentage of Victorian imports) rooftop solar in SA is negative $56.62 while gas is between $32.47 & $115.83
SA has been running 83.4% renewable on a rolling 3 day average and as I type at 1:30pm AEST is running 125% renewable, ie exporting & undercutting interstate fossils.