New South Wales had the highest average spot price, $65.32/MWh, and Victoria the lowest, $36.83/MWh.
Across the five regions the average was $47.16/MWh, down 28% on August 2026.
Prices went below zero for 216.9 hours in South Australia, 30% of the month, the most of any region.
The highest 5-minute price was $490.01/MWh in Tasmania on 26 September at 10:00.
The lowest was -$1,000.00/MWh in Tasmania on 26 September at 10:50.
For Tasmania, that is the most negative-price hours of the 13 months on record.
Spot prices by region, September 2026
| Region | Average | Lowest | Highest | Negative hours | Share of month | Intervals over $300 | Over $5,000 |
|---|---|---|---|---|---|---|---|
| Queensland | $57.10 | -$245.6430 September at 13:15 | $446.0120 September at 21:45 | 119.8 | 17% | 43 | 0 |
| New South Wales | $65.32 | -$18.511 September at 11:30 | $384.0920 September at 21:45 | 74.6 | 10% | 1 | 0 |
| Victoria | $36.83 | -$68.9820 September at 13:10 | $282.9924 September at 00:40 | 169.3 | 24% | 0 | 0 |
| South Australia | $37.71 | -$294.7110 September at 13:20 | $358.5728 September at 08:40 | 216.9 | 30% | 2 | 0 |
| Tasmania | $38.86 | -$1,000.0026 September at 10:50 | $490.0126 September at 10:00 | 152.1 | 21% | 4 | 0 |
FCAS, monthly average prices
| Market | QLD | NSW | VIC | SA | TAS |
|---|---|---|---|---|---|
| Raise regulation | $3.13 | $3.14 | $3.14 | $3.14 | $8.48 |
| Lower regulation | $1.47 | $1.45 | $1.45 | $1.47 | $9.38 |
| Raise 1 second | $0.02 | $0.02 | $0.02 | $0.02 | $0.02 |
| Raise 6 second | $0.04 | $0.04 | $0.04 | $0.05 | $6.81 |
| Raise 60 second | $0.03 | $0.03 | $0.03 | $0.05 | $0.35 |
| Raise 5 minute | $0.01 | $0.01 | $0.01 | $0.01 | $0.03 |
| Lower 1 second | $0.05 | $0.00 | $0.00 | $0.13 | $0.00 |
| Lower 6 second | $0.12 | $0.02 | $0.02 | $0.07 | $6.32 |
| Lower 60 second | $0.17 | $0.05 | $0.05 | $0.09 | $0.09 |
| Lower 5 minute | $0.07 | $0.06 | $0.06 | $0.07 | $0.05 |
Download the figures behind this report: spot prices and negative hours (CSV), FCAS averages (CSV). What this month would have meant for a battery: the BESS revenue calculator.
Data: Australian Energy Market Operator (AEMO), NEMWeb dispatch reports, used under AEMO's Copyright Permissions. Processed by ElectraGlobe. Prices are 5-minute dispatch prices in NEM time and may be revised. Informational only. Not for trading or financial decisions.