As we move towards summer, October typically brings an increase in solar generation and, with it, a series of renewable highs. In five of the last six years, renewable generation in October has exceeded September's total, typically driven by solar in the southern states. Consequently, October is also usually a month of low coal and gas generation.

This year, however, we saw a slight decline in renewable generation compared to September. Wind generation follows less predictable patterns than solar, with considerable variation during the spring months. This year saw a substantial decline, particularly in South Australia. In the west, the WEM recorded the strongest growth in renewables, with solar generation rising 32% on September's total. While unfavourable weather conditions and higher demand contributed to an increase in coal generation across the NEM, gas generation continued to decline. Once again, this trend was strongest in Queensland, where output from the more efficient combined-cycle gas plants fell by more than 70% compared to October last year.

South Australia recorded its highest monthly battery discharge at 54 GWh, an increase of 15 per cent on the previous record set in August 2026. Last month, we highlighted a new daily battery discharge record, achieved with minimal contribution from some of the state's largest batteries, including Templers BESS and Summerfield BESS. In October, Templers BESS discharged a total of 8.3 GWh, the second-highest output of any battery in the state. While Summerfield is still commissioning and will contribute more meaningfully in the months to come, it too has substantially increased its output.

Summerfield is the first four-hour battery in the state. South Australia was the last region, other than Tasmania, to bring a four-hour battery online, with the WEM achieving this milestone more than two years ago, and NSW becoming the first region in the NEM in March 2025.

South Australia's batteries now have a combined power capacity of 1,588 MW, roughly equivalent to its average electricity demand. However, the amount of energy these batteries can store remains relatively modest.

This is set to change. Multiple large four-hour batteries are under construction, with Hallett BESS expected to enter the grid next year, followed by four more in 2028. By 2029, South Australia's batteries are projected to have enough capacity to store energy equivalent to almost 20% of the state's average daily electricity consumption, well ahead of other regions.

Queensland recorded its highest instantaneous renewable generation on 12 October at 11:35 am, reaching 9,210 MW, a 10 per cent increase on the previous record set less than a month earlier, on 22 September.

Queensland's renewable generation records remain driven by solar. While wind generation has increased substantially over the last two years, it started from a low base. At the time of the latest record, 97% of renewable generation came from rooftop and utility-scale solar.

Queensland is also seeing greater renewable generation over longer periods, driven by two main factors: growing wind capacity and declining solar curtailment. Despite unusually weak solar conditions in October 2026, total renewable generation remained relatively stable.

October marked the fifth consecutive month in which curtailment was lower than in the same month the previous year. With electricity consumption in Queensland changing very little, the reduction in curtailment is best explained by increased battery charging. This includes home batteries, which are charging heavily around 11:10 am to take advantage of cheaper solar power. This phenomenon is occurring across the NEM.

NSW recorded its lowest monthly black coal generation at 2,816 GWh, 2 per cent below the previous record set in November 2025. Multiple outages contributed to the decline, with four generating units offline for much of the month. NSW has a particularly old coal fleet, with three of the state's four coal-fired power stations scheduled to close by 2033.

We have seen a continuing trend towards flatter coal generation profiles across the NEM, with consumption increasing during the day and growing battery and wind generation pushing coal output down in the evenings.

In October, NSW saw this effect particularly strongly, with coal generation increasing 16 per cent from 6AM to 6PM, before declining by 14% from 6PM to 6AM. Much has been made of the need for coal generators to ramp more sharply as renewable energy generation increases. Recently, however, we have seen the opposite trend, with coal ramping declining slightly across the NEM, and gas ramping falling sharply (largely explained by lower overall gas generation).

While NSW recorded an increase in renewable generation, much of the reduction in NSW coal generation during the evenings in October was offset by electricity imports from Queensland, much of it coal-generated.

The Goyder North wind farm has started construction. At 346 MW, the Neoen project will be the second-largest wind farm in South Australia, behind only the nearby Goyder South Wind Farm. Its 48 turbines, each rated at 7.2 MW, will be the equal-largest wind turbines in the NEM by capacity, and larger than any currently operating. The site will also be home to two 227 MW / 907 MWh batteries that are already under construction. The facility is expected to come online in December 2029.

The Parron Maam Marrang Wind Farm has been committed. At 489 MW, it will be the largest wind farm in Western Australia, bringing total committed wind capacity in the state to 1,114 MW, slightly above current operating capacity. Located about 200 km north of Perth, Parron Maam Marrang will be situated among some of the strongest-performing wind farms currently operating in the country.

The Wooreen Battery commenced operations on 6 October. At 350 MW / 1,400 MWh, it is now the largest battery operated by EnergyAustralia in the country. The facility is located beside the Jeeralang gas plants, also owned by EnergyAustralia.

The Tailem Bend 3 battery has commenced operations. The Vena Energy facility first operated on 24 October, just over 10 months after breaking ground in December 2025. At 204 MW / 408 MWh, the facility brings South Australia's total battery power capacity to 1,588 MW. This is the third Vena Energy battery to enter the grid, with a fourth, Bellambi BESS, under construction in NSW.

The Hazelwood BESS extension has achieved financial close. The original Hazelwood BESS, at 150 MW / 150 MWh, was the last one-hour battery to enter Victoria's grid in 2023. Since then, batteries have trended towards longer durations, with eight two-hour batteries, including the proposed 150 MW / 300 MWh Hazelwood extension, and four four-hour batteries. Construction on Hazelwood 2 is expected to begin later this year, with operations commencing in 2028.