The Australian Energy Regulator (AER) today published a report on significant prices in the National Electricity Market (NEM) across April to June 2026.
During the period, significant price outcomes were identified in Queensland, Tasmania and South Australia across both energy and Frequency Control Ancillary Service (FCAS) markets.
The outcomes were driven by local market and network conditions, including the availability of local generation, rather than sustained high prices across the quarter. Overall energy and FCAS prices were lower than in the same quarter last year.
A total of 14 days were considered in the quarter, with the highest 30-minute energy prices ranging from $251/MWh to $20,300/MWh, and FCAS prices ranging from $717/MW to $3,768/MW.
Four out of these 14 days, covering five events, were selected for detailed reporting using AER’s principles-based approach.
In Queensland and Tasmania, high FCAS prices were driven by network constraints requiring local FCAS supply. Technical limitations prevented low-priced capacity from being enabled and some rebidding contributed to the high prices. As well, local generation in Tasmania had to be used for both energy and FCAS, creating a trade-off which contributed to the FCAS prices and a high energy price. Tasmanian local FCAS costs overall, however, still fell from $9.8 million in Q1 2026 to $3.5 million this quarter.
In South Australia, significant price outcomes in energy occurred over two days under tight supply-demand conditions. Cold conditions led to high demand combined with very low output from wind generators and a cascading reduction in the state of charge of batteries. Network limitations and rebidding also contributed to the prices.
Background
Significant price outcomes reporting
The AER is required to report on significant price outcomes in the NEM.
The AER applies a principles-based approach when selecting the price outcomes to report on. As a result of applying this methodology, a minimum of four days will be reported on as significant price outcomes each quarter.
A significant price outcome may occur due to a variety of factors, including participant offers, bidding and rebidding, network constraints and outages, that adversely affect supply-demand conditions in the wholesale market.
The AER’s role in monitoring wholesale energy markets and reporting on high price events helps to enhance market transparency and compliance.
Our analysis provides a foundation to detect non-compliance, market irregularities, inefficiencies, and consumer harm. We draw on this work to advise stakeholders and market bodies on wholesale market issues.
The AER has published a Guideline for how we report into significant price outcomes.