New South Wales had the highest average spot price, $70.98/MWh, and Tasmania the lowest, $28.44/MWh.
Prices went below zero for 259.3 hours in South Australia, 36% of the month, the most of any region.
The highest 5-minute price was $6,874.28/MWh in Tasmania on 10 September at 18:00.
The lowest was -$1,000.00/MWh in Queensland on 29 September at 10:05.
Spot prices by region, September 2025
| Region | Average | Lowest | Highest | Negative hours | Share of month | Intervals over $300 | Over $5,000 |
|---|---|---|---|---|---|---|---|
| Queensland | $54.06 | -$1,000.0029 September at 10:05 | $528.731 September at 18:10 | 240.8 | 34% | 28 | 0 |
| New South Wales | $70.98 | -$86.3529 September at 09:45 | $599.991 September at 17:30 | 186.8 | 26% | 86 | 0 |
| Victoria | $55.02 | -$78.1814 September at 10:50 | $623.921 September at 18:05 | 226.0 | 32% | 79 | 0 |
| South Australia | $57.10 | -$575.697 September at 14:35 | $1,001.003 September at 00:55 | 259.3 | 36% | 106 | 0 |
| Tasmania | $28.44 | -$58.9119 September at 13:50 | $6,874.2810 September at 18:00 | 83.7 | 12% | 10 | 1 |
FCAS, monthly average prices
| Market | QLD | NSW | VIC | SA | TAS |
|---|---|---|---|---|---|
| Raise regulation | $9.01 | $9.00 | $9.00 | $9.00 | $13.13 |
| Lower regulation | $5.12 | $4.60 | $4.60 | $4.60 | $7.45 |
| Raise 1 second | $2.10 | $2.10 | $2.10 | $2.11 | $0.69 |
| Raise 6 second | $0.83 | $0.82 | $0.82 | $0.84 | $12.93 |
| Raise 60 second | $0.29 | $0.28 | $0.28 | $0.41 | $2.97 |
| Raise 5 minute | $0.22 | $0.21 | $0.21 | $0.21 | $0.34 |
| Lower 1 second | $0.40 | $0.09 | $0.09 | $0.11 | $0.01 |
| Lower 6 second | $8.23 | $0.25 | $0.25 | $0.25 | $13.93 |
| Lower 60 second | $7.38 | $1.15 | $1.15 | $1.15 | $0.87 |
| Lower 5 minute | $0.87 | $0.35 | $0.35 | $0.35 | $0.35 |
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.