NEM data spotlight: Australia’s solar PV sector achieves record October performance with 4,715GWh

Although it was to be expected that solar generation capacity was likely to beat last year’s performance, October 2025 has become the third-best month on record, trumped only by January 2025 (5,039GWh) and December 2024 (5,213GWh), both of which are the peak of Australia’s summer period.

However, with utility-scale and rooftop solar continuing to set new records several times a month now, the upcoming summer period will likely spell a dramatic increase year-on-year.

As detailed in the chart above, sourced from Open Electricity (formerly OpenNEM), both solar generation types experienced steady growth as seasonal conditions improved and daylight hours extended across the NEM.

It should also be noted that Australia’s solar PV sector recorded a 19.88% increase month-on-month; however, this was lower than the increase witnessed between the two corresponding months last year, which stood at 24.78%.

Across October 2025, much of the heavy lifting was done by the country’s rooftop solar sector, which broke the 3,000GWh threshold. This comes as no surprise, given that Queensland’s rooftop solar PV systems exceeded 5GW of output for the first time in October, marking a significant milestone in Australia’s distributed solar capacity expansion.

Meanwhile, utility-scale solar recorded its fourth-highest generation figure across the month, with 1,672GWh.

Recent analysis by the Australian Energy Market Operator (AEMO) revealed that grid-scale solar generation achieved an average output of 1,699MW in the third quarter of 2025.

Rooftop solar PV averages 98.5GWh across October

Perhaps one of the most striking figures from October 2025 was that the average for rooftop solar PV generation reached 98.5GWh, while utility-scale solar averaged 53.6GWh.

As shown in the graph above, which breaks down the daily recorded generation figures for utility-scale and rooftop solar PV, the best day for combined generation was 15 October, with a combined total of 186GWh. This is 27GWh higher than last month’s best day, 29 September, when generation reached 159GWh.

It is worth noting that the daily totals range from a low of 108GWh on 28 October, with most days falling between 130GWh and 170GWh.

Rooftop solar PV consistently outperformed utility-scale generation, averaging 97.4 GWh daily compared to 54.4 GWh for utility-scale systems – a significant 79% higher output.

Utility-scale solar generation showed considerable variability, ranging from a low of 36GWh on 28 October to peaks of 72GWh on 24 October. The system demonstrated moderate consistency, with several days clustering around the 50-60GWh range. However, notable dips occurred on days 5, 9, 22 and 28 October, suggesting weather-related impacts or maintenance activities.

Rooftop solar PV generation exhibited greater stability and higher overall performance, with output ranging from 71GWh to 118GWh. Peak generation occurred on 15 October (118GWh), while the lowest output was recorded on 26 October (71GWh). The distributed nature of rooftop installations appears to provide more consistent generation, with most days producing between 90-115GWh.

Major fluctuations in pricing across utility-scale and rooftop solar

The 31-day pricing data reveals significant volatility and contrasting patterns between utility-scale and rooftop solar markets in Australia. Both sectors experienced substantial price fluctuations, ranging from profoundly negative to strongly positive values, reflecting the complex dynamics of renewable energy markets.

Utility-scale solar pricing demonstrated extreme volatility, with prices ranging from AU$17.03/MWh (US$11.12/MWh) on 5 October to a peak of AU$73.51/MWh on 28 October.

The sector experienced extended periods of negative pricing during the first five days, indicating oversupply conditions where generators were paid to offload excess energy. However, the market showed remarkable recovery potential, with several days recording substantial favourable prices above AU$40/MWh, particularly on 9 October, 17 October, 21, 23, 25, 28, 29 and 31 October.

Rooftop solar pricing followed similar volatility patterns but with generally lower peak values, ranging from -AU$27.70/MWh on 5 October to AU$50.95/MWh on 31 October. Notably, rooftop systems experienced more severe negative pricing during oversupply periods, with intense discounts on 4 October and 5 October (-AU$22.81/MWh and -AU$27.70/MWh, respectively).

This suggests rooftop solar faces greater challenges during peak generation periods when grid absorption capacity is limited.

A price correlation was evident between the two sectors, with both experiencing negative pricing during the same periods (1-5, 11, 14, 16, and 19 October) and positive spikes often co-occurring.

However, the magnitude of price movements differed significantly, with utility-scale solar generally commanding higher favourable prices during favourable market conditions, likely due to its grid-scale integration advantages and more sophisticated market participation mechanisms.

You can explore previous solar generation performance in our NEM data spotlight series, with all entries available to PV Tech Premium subscribers.